Bob's Blog on Central Texas Weather

Wednesday night, an area of rain showers and thunderstorms spread east across the region along a wave of low pressure. Most totals averaged around a quarter inch or less. However, an area of very rain was observed across northern Travis and southern Williamson Counties, where a narrow band 3-4 inch totals were observed.

This afternoon, Doppler radar showed quiet conditions across the Hill Country and Central Texas regions, while scattered showers and thunderstorms continued across the middle and upper Texas coast. Despite the current lull in the rain, the weather pattern remains unsettled, and additional periods of rain showers and thunderstorms are forecast between Thursday evening/Thursday night and Saturday night.

Forecasters are monitoring the next wave of low pressure that is currently located over northern Mexico and moving to the east. This feature is forecast to spread across the Hill Country, Central Texas and the middle Texas coast this evening and overnight. Atmospheric parameters suggest some of these storms may potentially be strong to severe. The Storm Prediction Center has placed our region under a Marginal Risk, or 1 out of 5 risk, for severe thunderstorms through 7 am Friday. Damaging downburst winds and large hail will be possible with some of the thunderstorms. Rainfall from this next round rain and storms is forecast to generally average between 0.25 and 0.5 inches. However, isolated totals of 2-4 inches will be possible.

Additional periods of rain and thunderstorms are forecast Friday through Saturday night as more waves of low pressure move in from the west.  However, the timing of these next rounds of rain and thunderstorms will be difficult to nail down due to the uncertainty in the position of a surface boundary and model resolution of the upstream waves of low pressure.

For Friday through Friday night, there will be a 50-60 percent chance for showers and thunderstorms across the region. Some of these storms may be strong to possibly severe. Friday’s totals are forecast to generally average around a half inch. Totals closer to 1 inch can be expected across the northern Hill Country. In addition, isolated totals of 2-4 inches will be possible.

Saturday through Saturday night, there will be a 60-70 percent chance for showers and thunderstorms across the region.  Pockets of locally heavy rain will be possible. Totals Saturday through Saturday night are forecast to average close to a half inch, with isolated heavier totals of 2-4 inches possible. Most of the rain should taper off from north to south after midnight Saturday night.

Sunday’s weather will include a slight chance for rain showers through noon, mainly for areas located to the west of Interstate 35. Expect a mostly sunny sky. High temperatures will generally be near 88-90 degrees. Lows Monday morning will range from the low and mid-60s across the northern Hill Country, to the low 70s near the coast.

Adding all of the rain over the next 3 days together, totals are forecast to generally average between 1 and 1.5 inches. But do keep in mind, isolated heavier totals will be possible at a few locations.

NWS Rainfall Forecast for the Period 7 pm Thursday through 7 pm Sunday:

The outlook for Monday calls for dry and sunny. A slight chance for rain showers and isolated thunderstorms is forecast next Tuesday through Thursday as a trough of low pressure slowly spreads east across the southern Plains and North Texas. Rain amounts are not expected to be very heavy.

Bob

The much anticipated change in the weather is finally taking place across Central and South Texas. The heat dome, which has persisted across Texas since June, is finally weakening and sinking to the southwest. Monday’s analysis showed the center of the heat dome now off the coast of Baja, California. With a much weaker heat dome now in place, it’s opened the door for less hot temperatures and chances for rain. Winds in the middle and upper atmosphere across Texas are now flowing east-southeast out of New Mexico, along the northern periphery of the heat dome. Occasional waves of low pressure riding along these winds are expected to cause the development off scattered rain showers and thunderstorms each day this week. However, the highest probability for rain is forecast to occur late Thursday through Saturday.

Scattered light rain showers occurred across parts of the northern Hill Country Monday morning as an outflow boundary pushed southeast out of West Texas. According to LCRA’s Hydromet, most totals were generally less than a quarter. All of these showers are predicted to diminish Monday afternoon as they move into a more stable atmosphere. A mostly sunny to partly cloudy sky is forecast. Monday’s temperature is forecast to climb to the mid and upper 90s.

The chance for rain showers and scattered thunderstorms is forecast to increase across the northern and central Hill Country and the northern counties of Central Texas late Monday evening into Monday night when an upstream wave of low pressure helps push a weak cold front southeast out of West Texas. High resolution forecasts call for an area of showers and thunderstorms to develop across the Concho Valley and Heartland regions late this evening, with the activity slowly expected to move into the Hill Country after midnight. Some of the thunderstorms may strong or severe, possibly producing large hail and damaging winds. The Storm Prediction Center has placed the area generally west of a Goldthwaite, to Llano, to Kerrville line under a marginal risk for severe storms. There’s a slight chance some of the rain and storms could make into the Austin/Interstate 35 corridor before sunrise Tuesday. Totals from the overnight storms will range from around an inch across the northwestern Hill Country, to a tenth of an inch in the Austin area. Elsewhere, no rain is forecast.

Tuesday through Wednesday, forecasts call for just a slight chance for rain showers and thunderstorms across the Hill Country and Central Texas regions—mainly in the afternoon and evenings. The weak cold front across West Texas is predicted to slowly sink southeast into Central Texas Tuesday night into Wednesday. The probability for rain both days will be near 20 percent. Expect a mostly sunny to partly cloudy sky. High temperatures both days will range from near 90 degrees across the northern Hill Country, to the mid-90s across Central Texas, to the upper 90s across the coastal plains. Rain amounts, if any, should total less than a quarter inch.

Forecasts point toward increased chances rain showers and scattered thunderstorms across the entire region beginning Thursday and continuing through Saturday. The cold front is predicted to sag south into South Texas. At the same time, a series of waves of low pressure are forecast to track southeast out of New Mexico. With abundant moisture in place, waves of rain showers and scattered thunderstorms are forecast to move across the entire region between Thursday morning and Saturday evening. Some locally heavy rain will be possible. Some light rain may linger into Sunday, before a drier pattern takes hold Sunday afternoon into Sunday night.

The National Weather Service’s Rainfall outlook for the period 7 pm Thursday through 7 pm Saturday calls for widespread totals of around 1-1.5 inches across the Hill Country and Central Texas regions, and between 0.25 and 0.5 inches across the middle Texas coast.

Less hot temperatures are predicted late week and into the weekend. Daily high temperatures will range from around 88-90 degrees across the northern Hill Country, to the mid-90s across the coastal plains.

The outlook for next week calls for sunny, dry, and warm weather as a weak heat dome spreads back across Texas. Daily high temperatures are predicted to hold mostly in the mid-90s.

Tropical Weather Outlook

Weather conditions are quiet across the Gulf of Mexico and the Caribbean Sea. There are no systems which pose a threat for tropical development over the next seven days.

The National Hurricane Center is closely monitoring Hurricane Lee, located a few hundred miles north of the northern Leeward Islands, and on Tropical Storm Margot, located over the central subtropical Atlantic.

NHC forecasters are also following a tropical wave located over the far eastern tropical Atlantic, between the Cabo Verde Islands and the west coast of Africa. This system is producing disorganized showers and thunderstorms. Environmental

conditions do appear conducive for gradual development of this system, and a tropical depression could form by the weekend while it moves westward to west-northwestward at 15 to 20 mph over the central tropical Atlantic. Forecasts call for this system to bend northwest into open Atlantic and it should not pose a threat to the Gulf of Mexico.

Have a good week.

Bob

The doldrums of summer are finally coming to an end! Granted, we still have another 3 days of very hot temperatures in front of us, but all signs are pointing to the persistent dry and very hot summer pattern coming to an end next week. The wait for prolonged sub-100 degree weather is just about over! Beginning Tuesday, the Hill Country and Central Texas will enjoy temperatures below 100 degrees, and the temperature looks to stay below 100 degrees through the foreseeable future.

But before we get to the less hot temperatures next week, summer is going to flex its muscles one more time today and Saturday. Friday’s analysis showed a strong heat dome stretching from central Mexico to the southern Rockies, and centered over southeastern New Mexico. Due to the close proximity of the heat dome center, Friday is shaping up to be the hottest day of the week, with some of the hottest Septembers ever observed.

• High temperatures Friday are predicted to be between 104 and 108 degrees across the Hill Country and Central Texas regions, and between 102 and 106 degrees across the coastal plains.

Forecasts call for the heat dome to slowly weaken and retreat to the southwest beginning on Saturday. As a result, high temperatures are predicted to step down slowly this weekend into early next week.

• High temperatures Saturday are predicted to be between 103 and 105 degrees across the Hill Country and Central Texas regions, and be between 100 and 103 degrees across the coastal plains.
• High temperatures Sunday are predicted to be between 100 and 102 degrees across the Hill Country and Central Texas regions, and between 98 and 100 degrees across the coastal plains.
• High temperatures Monday are predicted to be near 98-100 degrees across the entire region.

There will be a slight chance for scattered mainly afternoon and evening showers and thunderstorms across the region Saturday, Sunday, and Monday as a weak cold front sags southwest into our area out of Oklahoma, Arkansas, and Louisiana. With a less intense heat dome overhead, the atmosphere will be more favorable for the development of a few scattered rain showers and thunderstorms along and south of the front. The probability for rain each day will near 20-30 percent. Rain amounts, if any, should total less than a quarter inch. Do note that a couple of the developing thunderstorms could be strong—producing gusty winds and small hail. Wind speeds this weekend are forecast to generally be between 5 and 10 mph.

Forecasts point toward an increasing chance for periods of rain showers and scattered thunderstorms across the region beginning late Tuesday and continuing through the end of the week. A somewhat stronger cold front is forecast to push south out of Oklahoma and spread south across Central Texas and the coastal plains region Wednesday, moving off the middle Texas coast Wednesday night. Showers and thunderstorms are forecast to develop ahead of and along the cold front. Behind the cold front, an overrunning pattern looks to set up Wednesday night and continue through next Friday night. Periods of rain showers thunderstorms are forecast as occasional waves of low pressure track southeast across Texas out of the southern Rockies. Some of the heaviest rains look to occur later next week.

Rain forecasts show the highest rain totals next week will occur across the northern Hill Country and the northern counties of Central Texas, with somewhat lower totals expected across the southern counties of Central Texas and towards the coast.

For Tuesday and Wednesday, totals are forecast to average between 0.5 and 1 inch across the northern Hill Country and around a quarter inch or less at most other locations. For Thursday and Friday, totals are forecast to range from 0.5 to 1.5 inches across the northern Hill Country, to around a half inch across Central Texas and the middle Texas coast.

NWS Rainfall Forecast:

NWS Rainfall Forecast for the Period 7 pm Friday through 7 pm Next Friday:

Expect a partly to occasionally mostly cloudy sky Wednesday through Friday.

High temperatures Tuesday through Friday are predicted to trend down several degrees due to the retrograding heat dome and the two cold fronts.

• High temperatures Tuesday through Friday are forecast to be in the upper 80s to 90 degrees across the northern Hill Country, in the low to mid-90s across Central Texas and the middle Texas coast.

Looking out into next weekend and the week of September 18th, generally dry and warm weather is forecast, with high temperatures mostly in the mid and upper 90s.

Tropical Weather Update

Weather conditions are quiet across the Gulf of Mexico and the Caribbean Sea. Tropical cyclone development is not expected here over the next seven days.

Across the tropical Atlantic, National Hurricane Center forecasters are closely monitoring Hurricane Lee, located several hundred miles east of the northern Leeward Islands, and Tropical Storm Margot, located over the eastern tropical Atlantic. Lee has become a category 4 hurricane, with maximum sustained winds of 130 mph. Lee is expected to pass well to the north of the northern Leeward Islands, the Virgin Islands, and Puerto Rico over the weekend and into early next week.

NOAA/Colorado State University/RAMMB 09/08/23 12:20 pm CDT

Comet Nishimura Swinging By for Binoculars and Telescopes and Just Maybe Our Eyes

Comet Nishimura is plunging toward the sun for a close encounter inside the orbit of Mercury on Sept. 17th. Increasing heat is causing the comet to brighten rapidly. Currently shining like a 5th magnitude star, it is barely visible to the unaided eye, but an easy target for digital cameras.

The comet starts this week very low in the dawn sky in the constellation Leo. You’ll need a low view to the east-northeast on the mornings of September 9th, 10th, and maybe 11th. The waning crescent Moon won’t pose interference. By the 13th or 14th the comet shifts to the low evening sky, just above the west-northwest horizon during early to mid-twilight. Day by day it will move leftward, but no higher, to stand barely over the west horizon on its perihelion date, the 17th. This is also its predicted date of peak brightness — possibly 2nd magnitude, not counting the ill effects of bright twilight and atmospheric extinction that low.

Have a good weekend.

Bob

We’re looking at another rough week of dry and very hot weather. But finally, there are some signs our extreme, never-ending summer might be finally be backing down. A change in the pattern is forecast to take place next week that will bring less hot weather along with a chance for rain.

But before we get to next week’s changing weather, more dry and very hot weather can be expected this week and through the upcoming weekend. The heat dome will again be the primary factor in our weather. Tuesday’s analysis shows the heat dome covering the south central U.S., with the center located over north central Mexico. Forecasts call for the center, or most intense part of the heat dome, to remain over Mexico today and Wednesday, then shift northeast to West Texas late week and through the weekend, bringing with it extreme temperatures.

For this afternoon and Wednesday, weather conditions will continue to be sunny and very hot! Thanks to the sea breeze and abundant tropical moisture, there will be a slight chance for a few scattered afternoon and evening rain showers and isolated thunderstorms across the coastal plains region, extending inland to La Grange. The probability for rain both days will be near 30 percent. For locations that do happen to see rain, totals will average less than a quarter inch. None of the rain activity is expected to make it to Central Texas or the Hill Country regions.

• High temperatures Tuesday and Wednesday are forecast to be between 101 and 103 degrees across the Hill Country and Central Texas regions, and between 98 and 101 degrees across the coastal plains.

Temperatures are forecast to trend even hotter Thursday through Sunday as the center of the heat dome moves north into West Texas.

• High temperatures Thursday through Sunday are forecast to be between 102 and 106 degrees across the Hill Country and Central Texas regions, and between 100 and 104 degrees across the coastal plains.

Parts of the Hill Country and Central Texas may see a slight chance for a few scattered rain showers Sunday as a weak wave of low pressure tracks southeast out of Oklahoma.

Forecasts call for the heat dome to begin weakening early next week as it slowly contracts southwest into Mexico. At the same time, a trough of low pressure is forecast to develop south out of central Canada the middle of next week, and this will allow for a cold front to push south into Texas during the middle and latter parts of next week.

The cold front is forecast to arrive sometime next Tuesday. This won’t be a “blue norther” by any means, but the front will bring less hot air into our region for the second half of the week and the following weekend.

The triple digit temperatures are forecast to come to an end next week as the heat dome moves away and the cold front spreads south. High temperatures Monday are still forecast to be near 100 degrees, but look to fall to the mid and upper 90s Tuesday, and to the mid-90s Wednesday through Friday.

The other big change for next week will be for an increasing chance for rain showers and thunderstorms Tuesday into Wednesday with the cold front. Forecasts call for fairly widespread totals close to a half inch, and possibly higher over the two-day period.

The National Weather Service’s 7-day  rainfall forecast goes out to 7 pm next Tuesday. It doesn’t account for any rain next Tuesday night or Wednesday, but it gives us an idea about the increasing chance for rain.

NWS Rainfall Forecast for the Period 7 pm Tuesday through 7 pm next Tuesday:

Tropical Weather Outlook

Weather conditions are quiet across the Gulf of Mexico and the Caribbean Sea. There are no systems here which pose a threat for tropical development over the next seven days.

In the central tropical Atlantic, a new tropical depression formed Tuesday morning and is forecast to become a powerful hurricane by the end of the week. As of now, this system is expect to bend north of the Caribbean Sea and poses little threat to the western Gulf of Mexico.

As of 10 am CDT Tuesday, the center of Tropical Depression Thirteen was located about 1425 miles east of the Lesser Antilles. The depression was  moving toward the west-northwest near 15 mph, and this motion is expected to continue for the next few days. Maximum sustained winds are near 35 mph with higher gusts. The depression is forecast to be a hurricane in a couple of days and could become a major hurricane in a few days.

Fire Weather Concerns

Near critical fire weather conditions continue over the Hill Country and the Interstate 35 corridor this week, and from the continued combination of above average temperatures, critically to extremely dry fuels, minimum relative humidity levels between 25 to 35 percent and south to southeasterly winds that increase each evening with inland advancement of the sea breeze.

Have a good week!

Bob

Well, we survived one of the hottest summers on record! Preliminary data indicates summer 2023 was the second hottest summer on record for Texas, behind 2011. However, individual sites such as Austin-Bergstrom Airport, San Antonio, Victoria, Llano, and Junction all recorded their hottest summers on record.

Summer 2023 was also one of the driest summers on record. Data shows Austin-Camp Mabry recorded only 1.31 inches of rain since June 1^st, making this the second driest summer on record. Llano recorded 1.24 inches, ranking as the 7^th driest summer on record. Even toward the coast, Columbus measured only 2.60 inches since June 1^st, ranking as the third driest summer total on record.

Any way you look at it, it’s been a rough three months. And although we’ve now turned the calendar to September, it’s still going to still feel a lot like August for a quite a while yet. This summer’s heat dome, fueled by the “Energizer Bunny,” is not showing any signs of backing down over the next couple of weeks. While the chances of seeing temperatures above 105 degrees appear low, readings of 100-105 degrees do look to continue into the middle of the month. Unfortunately, with the heat dome remaining in place, little to no rain is forecast over the next couple of weeks.

Heading into the holiday weekend, no significant changes in the hot and dry weather pattern are expected. Friday’s analysis did show a small area of low pressure in the middle and upper atmosphere located over East Texas and Louisiana. This low is not tropical in nature. Forecasts call for the low to track a little further west into Texas this weekend, then lift north into Oklahoma late Monday. The low is expected to pull tropical moisture inland beginning Sunday across Southeast Texas, with the moisture extending as far west as about Interstate 35. The increased moisture will help support the potential for widely scattered afternoon showers and thunderstorms across the coastal plains and parts of Central Texas east of I-35 Sunday and Labor Day. The probability for rain both days will range from 40 percent across the coastal plains, to just 20 percent further inland. Rain amounts, if any, are forecast to average between a tenth and a quarter inch.

No rain is forecast for the Austin area and locations west into the Hill Country Sunday through Monday.

Generally speaking, weather conditions Friday afternoon through Monday will feature a sunny sky and very hot temperatures. High temperatures are forecast to be near 100-103 degrees. Light southeasterly winds at 5-10 mph are forecast Friday through Sunday.

For next Tuesday into next weekend, the sunny, dry and very hot weather looks to continue as the center of the heat dome slides a little further to the east out of the Desert Southwest. A few scattered afternoon rain showers will still be possible across the coastal area Tuesday and Wednesday, but the chance for rain will diminish late next week. High temperatures are forecast to continue near 100-103 degrees.

For the week of September 11^th, forecasts call for few change as the heat dome continues across Texas and northern Mexico. High temperatures look to continue near 100-103 degrees.

Fire Weather Concerns

Dry to critically dry fuels continue across the Hill Country and Central Texas and with no significant rain in the forecast, near critical fire weather conditions can be expected this weekend and next week. Everyone is urged to exercise care with respect to all outdoor activities that could inadvertently cause wildfires. Avoid the use of welding or grinding equipment near grass and dry brush. In addition, avoid parking vehicles in tall, dry grass and weeds that could be ignited.

Do not toss cigarette butts on the ground. Report wildfires quickly to the nearest fire department or law enforcement office.

Tropical Weather Outlook

Weather conditions are quiet across the Gulf of Mexico and the Caribbean Sea. Tropical cyclone development is not expected in this area for at least the next seven days.

Across the Atlantic, the National Hurricane Center is closely following Hurricane Franklin, located about 680 miles northeast of Bermuda, Tropical Storm Jose, located about 835 miles east-northeast of Bermuda, Tropical Depression Gert, located roughly 655 miles east-southeast of Bermuda, and the remnants of Idalia, located 185 miles west of Bermuda.

A new tropical depression developed Friday morning over the eastern tropical Atlantic, about 375 miles northwest of the Cabo Verde Islands. The depression was moving toward the north-northwest near 8 mph. A motion toward the north-northwest and northwest at a faster forward speed is expected through Sunday. A turn toward the west-northwest is forecast later on Sunday. Maximum sustained winds are near 35 mph with higher gusts. Some strengthening is expected, and the depression is forecast to become a tropical storm Friday evening. The system is likely to weaken early Sunday and degenerate to a remnant low by late Sunday.

Finally, NHC forecasters indicate a tropical wave is expected to move off the west coast of Africa this weekend. Environmental conditions appear conducive for some gradual development of this system during the early and middle parts of next week, and a tropical depression could form while it moves westward to west-northwestward over the eastern and central portions of the tropical Atlantic.

Have a safe and enjoyable holiday weekend! For those spending time outdoors, make sure to stay safe in the heat; stay hydrated and take frequent breaks in the shade or indoors with A/C.

Bob

A late August “cold front” pushed through the area Sunday and Sunday night and has put an end to our recent streak of extreme temperatures. Sunday’s readings were among some of the hottest of the summer and were very close to all-time records. Showers and scattered thunderstorms developed ahead of and along the cold front over the Hill Country and the northern counties of Central Texas. Rain amounts generally averaged around a tenth of an inch, but there were a couple of isolated totals between 0.75 and 1 inch across the northern Hill Country.

Monday’s analysis showed the cold front located just offshore of the middle and upper Texas coast. Light north and northeasterly breezes were blowing across the region. Although the cold front is south of the area, there will be a slight chance for a few scattered showers and isolated thunderstorms across the Hill Country and Central Texas region this afternoon as a weak wave of low pressure tracks southeast out of West Texas. The probability for rain will be 20 percent, and rain amounts should only average around a tenth of an inch. A somewhat better coverage or scattered rain showers and thunderstorms is forecast for areas south of Interstate 10. Here, the chance for rain will be 40 percent and rain amounts should average between a tenth and a quarter of an inch.

Otherwise, Monday’s weather will feature a mostly sunny sky and slightly lower temperatures. Highs are forecast to range from the mid-90s across the northern Hill Country, to near 98-102 degrees across Central Texas and the middle Texas coast. Lows Tuesday morning will range from the upper 60s north, to the mid-70s across Central Texas, to the upper 70s near the coast.

Sunny, dry, and hot weather is forecast across the region Tuesday and through the upcoming weekend. The center of the summer heat dome is currently located over the Desert Southwest and is forecast to remain over that general area into the weekend. Our region will be on the eastern periphery of the heat dome. A northerly wind flow in the middle and upper atmosphere will keep our atmosphere dry and quite stable. As a result, no rain is forecast.

Temperatures will be hot this week, but not quite to the level we saw over the weekend.

• Tuesday will see the least hot readings of the week, with high temperatures generally in the upper 90s.
• High temperatures Wednesday through Sunday are forecast to generally be near 100-102 degrees.

Looking ahead to Labor Day and early next week, forecasts call for a slight chance for scattered rain showers and thunderstorms for areas located east of Interstate 35 as a weak area of low pressure in the upper atmosphere develops over the northwestern Gulf. The low is predicted to pull an area of tropical moisture inland, resulting in a 20-30 percent chance for scattered rain showers and thunderstorms. Rain amounts, if any, are predicted to stay below a quarter inch. Unfortunately, the slight chance for rain is not forecast to extend into Central Texas or the Hill Country.

Aside from this slight chance for rain, more hot and dry weather is forecast next week as the center of the heat dome stays out to the west or across the southern Plains.

High temperatures next week are forecast to remain near 100-103 degrees at most locations.

Fire Weather Concerns

Critical to near-critical fire weather conditions will be in place throughout the week due to extremely dry fuels and the lack of rain. 20 foot winds of 10 to 15 mph with a few gusts to 25 mph and minimum relative humidity levels of 15 to 25 percent are forecast each afternoon.

Tropical Weather Outlook

There are currently no tropical weather concerns for the western Gulf of Mexico.

Tropical Storm Idalia, located just off the western tip of Cuba poses no threat to Texas. As of 1 pm CDT, the tropical storm was moving toward the north near 8 mph. A northward motion is expected through tonight, followed by a faster north-northeast motion on Tuesday and Wednesday. On the forecast track, the center of Idalia is forecast to pass near or over western Cuba tonight, over the extreme southeastern Gulf of Mexico by early Tuesday, and reach the Gulf coast of Florida on Wednesday. Maximum sustained winds have increased to near 70 mph with higher gusts.  Idalia is forecast to become a hurricane later today and a dangerous major hurricane over the northeastern Gulf of Mexico by early Wednesday.

Hurricane Franklin, a category hurricane is located about 475 miles southwest of Bermuda, moving toward the north near 9 mph. This northward to north-northeastward motion with a slightly faster forward speed is expected during the next few days.  On the forecast track, the center of Franklin is expected to pass well to the west of Bermuda on Wednesday. Maximum sustained winds are near 145 mph with higher gusts. Additional strengthening is possible today, but gradual weakening is expected to begin later Tuesday.

A tropical wave is forecast to move off the west coast of Africa in the next day or so. Environmental conditions appear marginally favorable for gradual development of this system, and a tropical depression could form later this week while the system moves  westward or west-northwestward across the eastern tropical Atlantic. This system is looking like it will bend north into the open Atlantic and not be a threat to the Caribbean Sea or the Gulf of Mexico.

August Blue Supermoon this Wednesday Night

Full Moon will occur at 8:36 pm CDT Wednesday night and it should be quite special! The August full Moon will be the third supermoon of 2023, and it will be the biggest full moon of 2023. In addition, being the second full Moon of this month, it is also a so-called blue moon. Having two supermoons in the same month is relatively rare: last time was in 2018, next time will be in 2037.

Bob

The summer heatwave drags on, with no significant relief expected anytime soon.

Thursday turned out to be the hottest day of the summer for the coastal plains region, where the temperature reached between 105 and 107 degrees across the area between La Grange and Bay City. These readings were just shy of the all-time record high temperatures. Across the Hill Country and Central regions, Thursday’s temperature also climbed to between 105 and 107 degrees, but hotter readings have been recorded earlier in the summer.

Mostly sunny and very hot weather will continue this afternoon through Sunday as the summer heat dome continues to heavily influence our weather. After spending nearly a week over the Midwest, the center of the heat dome will be moving back to the south and southwest. Forecasts call for the center of the heat dome to be over Oklahoma this weekend, then move to the Desert Southwest early next week. Heat Advisories and Excessive Heat Warnings will continue into the weekend.

• High temperatures Friday through Sunday are forecast to be between 104 and 107 degrees across the Hill Country and Central Texas regions, and between 103 and 106 degrees across the coastal plains.

There will be a very slight chance for a few scattered rain showers and isolated thunderstorms across the region Friday through Sunday. Forecasts call for some small waves of low pressure to rotate around the base of the heat dome and track from east to west across Central Texas and the Hill Country. In addition, slightly higher moisture levels are also forecast to be in place across the region. Both factors are expected to help with the development of afternoon scattered rain showers and isolated thunderstorms. The probability for rain will only be  20 percent, and for locations that do see rain, totals are forecast to only average around a tenth of an inch.

There will be  a somewhat better chance for scattered rain showers and thunderstorms taking place across the Hill Country and Central Texas regions Monday into Monday evening, and across the coastal plains region Tuesday into Tuesday evening when a weak cold front slides south out of the southern Plains. Forecasts call for the cold front to reach the northern Hill Country early Monday morning, then slowly slide south across Central Texas Monday afternoon into Monday evening. The front is forecast to move across the middle Texas coast Tuesday into Tuesday evening. Moisture convergence along and behind the cold front is expected to cause the development of scattered rain showers and thunderstorms. The probability for rain will be between 30 and 50 percent. Rain amounts with the front are forecast to generally average around a quarter inch or less. Unfortunately, the coverage of precipitation looks to remain scattered enough that some areas may miss out on the rain.

The rain is forecast to taper off from north to south across Central Texas Monday into Monday evening, and across the coastal plains region Tuesday into Tuesday evening. Sunny and dry weather is forecast next Wednesday through Friday.

NWS Rainfall Forecast for the Period 7 am Friday through 7 am Wednesday:

“Slightly” lower temperatures are forecast behind the cold front next Tuesday through Friday.

• High temperatures Monday are forecast to be between 100 and 105 degrees across the entire region.
• High temperatures next Tuesday through Friday are forecast to be in the upper 90s across the Hill Country and the coastal plains, and near 98-102 degrees across Central Texas.

Looking out to next weekend and the week of September 4^th, forecasts call for a mostly sunny, dry, and hot weather pattern as the heat dome returns to Texas and the southern Plains states. A few sea breeze showers will be possible, but the overall pattern looks dry. High temperatures through the period are predicted to be between 102 and 104 degrees across the Hill Country and Central Texas regions, and between 98 and 102 degrees across the coastal plains.

Tropical Weather Outlook

The National Hurricane Center is closely monitoring a broad area of low pressure located over the northwestern Caribbean Sea that is producing a disorganized area of showers and thunderstorms. Environmental conditions appear conducive for gradual development of this system during the next several days, and a tropical depression is likely to form late this weekend or early next week. Steering currents are forecast to cause the system to move northward over the northwestern Caribbean Sea and eastern Gulf of Mexico over the next few days. The system is expected to make landfall somewhere over western Florida the middle of next week, posing little to no threat to the western Gulf of Mexico. NHC forecasters are giving the disturbance a 70 percent chance for tropical development over the next seven days.

Elsewhere, the Hurricane Center is issuing forecasts on Tropical Storm Franklin located a couple of hundred miles west of Grand Turk Island. Franklin is forecast to track to the west of Bermuda early next week.

NHC is also following the remnants of Emily located over the central subtropical Atlantic, and another area of disturbed weather located midway between the Cabo Verde Islands and the northern Leeward Islands. Neither system poses a threat to the Gulf of Mexico over the next week.

A tropical wave is forecast to move off the west coast of Africa early next week. Some slow development of this system is then possible late next week while the system moves westward across the tropical Atlantic.

Catch Jupiter and Saturn Now in the Evening Sky

Jupiter rises about an hour after dark. Watch for it to come up low in the east-northeast sky. Jupiter shines highest in the south just before the beginning of dawn.

Saturn rises at sunset and it’s at opposition on August 26th. In late twilight you’ll find Saturn glowing as the brightest thing low in the east-southeast sky. It’s at a fairly good height for telescopic observing by 11 p.m.

Venus (about magnitude –4.6) is now in the morning sky before dawn. Look for it above the horizon due east. It will get higher and easier to find every day through the fall.

Have a good weekend!

Bob

The center of Tropical Storm Harold made landfall on Padre Island, adjacent to Kenedy County around 10 am Tuesday morning. Maximum sustained winds were near 50 mph with higher gusts at the time of landfall. Steady weakening is now forecast, and Harold is expected to become a tropical depression later today. Harold is moving toward the west-northwest near 21 mph and this motion is expected to continue, taking the system inland over southern Texas and northern Mexico this afternoon. The clouds and moisture associated with Harold are forecast to spread west-northwest into Mexico tonight and Wednesday. Harold’s remnants are not expected to have any impact on Central Texas or Hill Country weather on Wednesday.

Earlier this morning, a wind gusts to 44 mph was observed at Palacios. A gust to 63 mph was recorded at the Corpus Christi Naval Air Station. The Corpus Christi Airport recorded a gust to 54 mph.

As of late Tuesday morning, Doppler radar showed widespread rain and thunderstorms covering Deep South Texas, generally south of a line from around Victoria, to Pleasanton, to Eagle Pass. Scattered rain showers and isolated thunderstorms were noted across the middle and upper Texas coast, extending inland to near Interstate 10.

NOAA/Colorado State University/RAMMB 08/22/2023 12:20 pm CDT

The circulation around Harold is expected to pull a limited amount of tropical moisture inland to parts of Central Texas and the Hill Country this afternoon. This will result in a slight chance for a few spotty rain showers and isolated thunderstorms. The probability for rain at any given location will be 20 percent. For locations lucky enough to see any rain, totals are forecast to average close to a tenth of an inch. Afternoon high temperatures are predicted to be near 100-103 degrees.

For the middle Texas coast, the probability for scattered rain showers and thunderstorms will be around 50 percent this afternoon, decreasing to 30 percent this evening. Rain amounts will range from around a half inch across Matagorda County, to less than a quarter inch across Colorado County. Afternoon high temperatures are predicted to be in the upper 90s.

NWS Rainfall Forecast for the Period 7 am Tuesday through 7 am Wednesday

For Wednesday and Thursday, mostly sunny, dry and very hot weather is forecast as the center of the heat dome begins to shift from the Midwest to the southern Plains. Expect high temperatures of 104-106 degrees across the Hill Country and Central Texas regions, and to around 100-104 degrees across the coastal plains.

For Friday and the upcoming weekend, the excessive/dangerous heat looks to continue. However, a few scattered rain showers and thunderstorms will be possible across the region each day as wind flow off the Gulf of Mexico in the lower atmosphere pulls a few weak waves of low pressure inland. The weak waves are expected to cause a 20 percent chance for scattered rain showers and isolated thunderstorms each day. Unfortunately, significant rain is not expected. Spotty totals to near a tenth of an inch are forecast each day.

High temperatures Friday through Sunday are predicted to be near 104-106 degrees across the Hill Country and Central Texas, and near 100-104 degrees across the coastal plains.

The outlook for next week calls for more triple-digit heat with low probabilities for rain.

Increased Fire Weather Concerns Tuesday Afternoon

Wind speeds of 10-20 mph with occasional gusts to 30 mph are predicted for much of the area this afternoon.  The combination of the breezy conditions, low relative humidity levels, and extremely dry fuels will lead to critical fire weather conditions across the most of the area, but in particular, the northern counties of Central Texas, including Metro Austin.

The National Weather Service has posted a Red Flag Warning for Llano, Burnet, Williamson, Gillespie, Blanco, Hays, Travis, Bastrop, and Lee Counties from 1 pm through 8 pm Tuesday. Under these conditions, any fires that develop can spread rapidly and exhibit high resistance to control. Any outdoor activity that could produce flames or sparks is discouraged.

Bob

Thursday turned out to be the hottest day so far this summer for locations along and just east of Interstate 35. High  temperatures included 110 degrees at Austin-Camp Mabry, and 109 degrees at Austin-Bergstrom and Georgetown. San Marcos, New Braunfels, and Burnet all recorded highs of 108 degrees. High temperatures across the Hill Country were generally between 105 and 109 degrees. It was also extremely hot across the coastal plains, were highs were between 101 and 105 degrees!

The main culprit for the extremely hot temperatures continues to be a large and powerful heat dome that remains parked over the southern and south central U.S. Friday’s analysis showed the heat dome centered over eastern Oklahoma. Forecasts call for the center of the heat dome to shift northeast to the middle Mississippi Valley region beginning Sunday and to remain over that area through next Thursday. For Central and South Texas, the extremely hot weather will continue, but we can expect a very slight lowering of high temperature this weekend and early next week as the center of the heat dome shifts further northeast.

• High temperatures Friday are forecast to be between 105 and 108 degrees across the Hill Country and Central Texas regions, and between 100 and 105 degrees across the coastal plains.
• High temperatures Saturday through Monday are forecast to be between 103 and 107 degrees across the Hill Country and Central Texas regions, and between 100 and 103 degrees across the coastal plains.
• High temperatures Tuesday are forecast to be between 98 and 101 degrees across the Hill Country and Central Texas regions, and between 95 and 98 degrees across the coastal plains.

Gulf and Tropical Weather Update

The National Hurricane Center has raised the probability for tropical cyclone development in the western Gulf of Mexico next week to 40 percent, or a medium chance.

National Hurricane Center forecasters continue to monitor a strong tropical wave located over the southern Bahamas that is moving to west. The wave is predicted to reach the eastern Gulf of Mexico late this weekend, then continue westward across the central Gulf Monday. The system is then forecast to approach the Texas coast sometime late Tuesday or Wednesday.

The National Hurricane Center’s Friday midday update calls for a medium chance, or 40 percent probability, for tropical development as the system moves across the Gulf. The various forecast solutions range anywhere from just a tropical wave, to a weak tropical storm when the system moves inland sometime next Tuesday or Wednesday. Conditions do look to be generally favorable for some slow tropical development as the system will be moving over very warm ocean waters. This may end up being a situation where whatever is going to happen with tropical development will occur just before the system moves inland.

The various forecast solutions have come into somewhat better agreement on where this system is expected to move inland. The latest solutions generally point toward the system moving inland somewhere along the middle or lower Texas coast mid-week. I will point out that tracks further north and to the south still cannot be ruled out.

Regardless of whether the system develops into a tropical depression or weak tropical system, it is expected to bring a surge of clouds and tropical moisture onto the middle and lower Texas coast Tuesday into Wednesday. As of now, it appears the highest amount of tropical moisture will remain along and south of the I-10 corridor and west of the Interstate 35 corridor.  There will likely be a strong south to north gradient in the probability for rain across the area next week. There is still too much uncertainty to get a good handle on how much rain will fall and over which areas. It will be a battle between the inland-moving moisture and rain bands, and the strong ridge to the north and northeast.

National Weather Service rainfall forecasts call for the highest totals to occur close to the coast, with the lowest totals expected across the northern counties of Central Texas.

NWS Rainfall forecast for the period 7 pm Friday through 7 next Friday:

• High temperatures Wednesday are forecast to be near 98-101 degrees across the Hill Country and Central Texas regions, and in the mid to upper 90s across the coastal plains.

Late Next Week into the Last Week of August

Moisture from the tropical system is forecast to shift to the west and northwest late Wednesday, ending the chance for rain across our region. Meanwhile, the center of the heat dome is predicted to shift southwest and set up somewhere over the southern Plains. Dry and hot weather is forecast.  Daily high temperatures are forecast to be between 102 and 105 degrees across the Hill Country and Central Texas regions, and between 98 and 101 degrees across the coastal plains.

Hyperbolic Comet Nishimura

A hyperbolic comet is falling into our solar system. Japanese amateur astronomer Hideo Nishimura discovered it just a few days ago in the constellation Gemini. Although it is relatively dim right now (magnitude +9), Comet Nishimura could soon brighten more than 100-fold to become a naked-eye object in mid-September.

A “hyperbolic comet” is a comet with too much energy to remain trapped inside the solar system. It will visit us only once, with the sun acting as a gravitational slingshot, sending the comet hurtling back into deep space after its flyby.

Because this is Comet Nishimura’s first trip to the inner solar system, it is extra unpredictable. On Sept. 18th, the comet will make its closest approach to the sun deep inside the orbit of Mercury. Anything could happen when intense sunlight touches the comet’s pristine surface for the first time. Possibilities range from dramatic brightening to a disappointing fizzle. Standard models suggest a peak brightness of 3rd magnitude. This would make it visible to the naked eye from rural areas. (Courtesy Spaceweather.com)

Stay tuned for further updates.

Have a great weekend.

Bob