LCRA chief meteorologist Bob Rose writes regularly on weather topics. Do you have a weather question for Bob? Send an email to Bob Rose.
Bob's Video Blog: What happened to winter?
A very warm January for most of Central Texas has left people asking if winter is ever going to happen. Bob Rose thinks there's still some cold weather in the forecast and he also has some good news concerning La Nina.
Bob’s Blog on Central Texas weather
A Cloudy, Damp Weekend. Cooler Temperatures Saturday, Continuing through Next Week. FRIDAY, FEBRUARY 03, 2012 04:25 PM
A quick update on this weekend’s weather. The latest forecast calls for the development of widespread rain and scattered thunderstorms late this afternoon, continuing overnight and into Saturday. There is a slight risk some of the thunderstorms could become severe across the northern counties of the Hill Country and he northern counties Central Texas. Another period of rain looks to develop Sunday as an area low pressure tracks north out of Mexico. A partly to mostly cloudy sky will follow early next week.
Late this afternoon, a cold front was across northwest Texas, stretching from near Childress to near Midland and west into southern New Mexico. Out ahead of the front, scattered thunderstorms have been developing between Wichita Falls and San Angelo. Other rain showers and thunderstorms were occurring across the eastern third of Texas, roughly east of a line from Gonzales to Waco. Rain showers and scattered thunderstorms look to increase in areal coverage late this afternoon and evening across the Hill Country and Central Texas regions out ahead of the cold front. Some of the thunderstorms across the northern counties of the Hill Country and Central Texas could be strong to possibly severe although most of the strongest storms will likely occur across northern Texas. This area of rain and storms will slowly sink southeast toward the coast late tonight and into Saturday morning. The rain should taper off across the Hill Country and Central Texas regions by Saturday afternoon but rain showers look to continue for much of the day towards the coast. Rainfall over the next 24 hours is forecast to average between 0.25 and 0.5 inches across much of the Hill Country. For Central Texas and the coastal plains regions, rain totals will generally average around between 1 and 2 inches. The National Weather Service has issued a Flash Flood Watch from 8 pm this evening through noon Saturday for areas along and to the east of Interstate 35. This general area saw significant rain last week and the ground is still quite wet.
Cooler temperatures will develop behind the cold front. Lows Saturday morning will range from the low and middle 40s across the northern Hill Country to the low 50s around Austin to the low 60s near the coast. The high temperature Saturday will range from the mid 50s northwest to near 70 degrees towards the coast. Lows Sunday morning will range from the upper 30s to 40 degrees northwest to the upper 40s near the coast.
The weather on Sunday will be cloudy, cool and damp as an overrunning pattern develops. A trough of low pressure tracking northeast out of Mexico will cause the development of widespread clouds and scattered light rain. The most favorable area for rain looks to develop across the coastal plains region and the southern counties of Central Texas. Here, rain amounts of 0.5 to 1 inch will be possible. Elsewhere, rain amounts will generally be between 0.25 and 0.5 inches. The rain should taper off Sunday evening as the trough exits the region. Sunday’s temperature will be cool with high temperatures ranging from the upper 40s across the northern Hill Country to the middle 50s near the coast. A light freeze will be possible across parts of the Hill Country and Central Texas Sunday night. Lows Monday morning will include the low 30s Hill Country, low and middle 30s central and middle to upper 30s towards the coast.
A partly to mostly cloudy sky and cool temperatures are forecast next Monday and Tuesday. Today’s data indicates another chance for rain will develop next Wednesday and Thursday.
I hope everyone has a good weekend. After a mild week, get ready for some cooler weather over the next several days.
Bob
Previous Blog Entries
Chance for Rain Increasing Tonight and Friday. Spotty Rain Lingering into Sunday. THURSDAY, FEBRUARY 02, 2012 06:08 PM [+] Click to view this entry
Mostly cloudy and damp weather conditions look to develop across the region tonight and continue in place through most of the weekend. Widespread light to moderate rain is forecast tonight and Friday with occasional periods of rain over the weekend. Although the rain will last into Sunday, rainfall totals are not expected to be heavy as what we saw last week. Most totals across the Hill Country and Central Texas should be in the range of 0.5 to 1 inch. Meanwhile, totals across the coastal plains region will be in the range of 1 to 2 inches. The chance for rain is forecast to diminish Sunday afternoon followed by generally dry weather next Monday through Wednesday. A slight chance for rain does look to return to the forecast late next week. The temperature will turn slightly cooler beginning Friday night when a cold front moves across the area. These slightly cooler readings then look to hold in place through most of next week.
A trough of low pressure in the upper atmosphere developing across the southern Rockies is helping pull moisture into Texas off the Gulf of Mexico and the Pacific Ocean. Today’s atmospheric soundings indicated the atmosphere across southern Texas has become quite moist over the past 24 hours. The increasing moisture combined with decreasing atmospheric stability is leading to the development of scattered showers and isolated thunderstorms this afternoon. Overnight, this activity should increase in areal coverage as the atmosphere becomes more unstable.
A wave of low pressure attached to the trough of low pressure across the southern Rockies is forecast rotate northeast across the northwestern part of Texas Friday, causing an increasing chance for rain and scattered thunderstorms across the region. Today’s data indicates the most favorable area for strong to possibly severe storms will be across North Texas. Further south, most of the storms should stay below the severe threshold. Friday’s temperature will be mild with highs generally in the mid and upper 70s. But a cold front will sweep south into Texas Friday, with the front moving across the Hill Country and Central Texas regions Friday night and the coastal plains region Saturday morning. There will be an increasing chance for widespread rain and thunderstorms along and just behind the cold front. The chance for rain will then decrease behind the cold front Saturday morning into Saturday afternoon. Some breaks in the clouds will even be possible Saturday afternoon. High temperatures Saturday will generally be in the low 60s across the Hill Country and Central Texas and near 70-72 degrees towards the coast.
The cold front is forecast to move into the Gulf of Mexico Saturday afternoon. Meanwhile, a weak trough of low pressure in the upper atmosphere is forecast to track inland over northwestern Mexico out of the Pacific. This system looks to cause an overrunning pattern of clouds and spotty light rain across Central and South Texas beginning late Saturday night into Sunday. Rain totals during this period don’t look to be very high. The chance for rain will then diminish Sunday night. Lows Sunday morning will be near 38-40 degrees across the Hill Country, near 42-45 degrees across Central Texas and near 50 near the coast. Highs on Sunday will be mostly in the mid and upper 50s.
The National Weather Service’s quantitative precipitation forecast calls indicates rain totals over the next 5 days will generally average between 0.5 and 1 inch across the Hill Country and Central Texas but totals could be between 1 and 2 inches across the coastal plains region.
Today’s medium-forecast data indicates the weather across our region will be partly to mostly cloudy Monday through Wednesday. The solutions call for a moist flow off the eastern Pacific causing widespread clouds. High temperatures each day will be mostly in the low 60s with lows generally in the low and middle 40s. Today’s data indicates increasing moisture off the Pacific will lead to a slight chance for rain next Thursday and Friday. But current data suggests rain amounts will be light. Another cold front is forecast to push south across the region sometime next Friday, reinforcing the “cooler” conditions already in place. High temperatures late next week will stay near 60-62 degrees with lows in the upper 30s to low 40s.
Long-range data still doesn’t show any arctic air breaking loose and spreading south into Texas over the next ten- to-fourteen day period.
Bob
January Ending Very Mild. Another Chance for Rain Expected Friday. TUESDAY, JANUARY 31, 2012 05:54 PM [+] Click to view this entry
The month of January will close out as a very mild month with the temperature across Central and South Texas generally averaging between 2 and 4 degrees above normal. After a fairly cool December, winter seems to have gone into hibernation. Nationwide, the story is the same, if not milder. Take a look at the following chart, courtesy of the High Plains Regional Climate Center, showing the temperature departure from normal for the contiguous US:
Note the milder than normal temperatures stretching from coast to coast. The Mississippi Valley region has been running almost 6 to 9 degrees above normal while the northern Plains has been running between 9 to 12 degrees above normal! This is phenomenally mild for January. This could end up being one of the warmest Januarys on record for the US. Meanwhile, the state of Alaska is experiencing one of its coldest Decembers on record with an average monthly temperature of between 20 and 30 degrees below zero at several locations. Fortunately, that bitterly cold air will stay well to the north. But as I mentioned yesterday, we’ll need to watch the weather pattern over the next couple of weeks as the Jet Stream assumes a configuration that could potentially deliver some of this cold air south into the US.
Today’s weather has again been unseasonably mild with temperatures warming into the 70s. By the way, last night’s trough of low pressure brought some significant rain to parts of the region. Totals close to an inch or more were observed in an area stretching from just east of Austin to just east of San Antonio. Other totals close to an inch were observed near the middle Texas coast. Elsewhere, most totals across Central Texas were between 0.25 and 0.5 inches. Across the Hill Country, most totals were less than a quarter inch.
With a mild and moist air mass in place, conditions will be favorable for the development of widespread clouds and patchy fog overnight. Some occasional drizzle will be possible as well. Lows Wednesday morning will include the low and middle 50s across the Hill Country with upper 50s to low 60s at most other locations. Clouds will linger through Wednesday morning with the sky becoming partly cloudy in the afternoon. A weak wave of low pressure tracking east across the southern Plains states Wednesday afternoon might spark a couple of showers or isolated thunderstorms across the coastal plains region and the eastern counties of Central Texas. Otherwise, most locations should stay dry with high temperatures in the middle70s. A mostly cloudy sky looks to redevelop Wednesday night with lows Thursday morning ranging from the low 50s north to near 60 degrees towards the coast.
Forecasters continue to monitor a large trough of low pressure in the upper atmosphere that is expected track south across the West Thursday, reaching the Desert Southwest on Thursday. The trough is forecast to track northeast across northwestern Texas on Friday, reaching the southern Plains states Saturday. Ahead of the trough, considerable moisture will spread north out of the Gulf of Mexico and across Texas Thursday, resulting in a mostly cloudy to cloudy sky. High temperatures will be mostly in the low 70s. A slight chance for rain looks to develop Thursday night. This will be followed by a better chance for rain and scattered thunderstorms Friday into Friday night as a Pacific cold front pushes across the state. Unlike last week’s event, the threat for severe storms with this week’s system is not expected to be very high. Today’s forecast data indicates the most significant rains will occur generally along and to the east of Interstate 35. Here, totals will generally average between a half inch and an inch. Across the Hill Country, totals are forecast to average between 0.25 and 0.5 inches
The following National Weather Service graphic shows the amount and areal extent of rain forecast between this evening and Sunday evening:
As the trough lifts northeast Friday night, I expect the rain to slowly taper off from west to east. Clouds will clear with the sky becoming mostly sunny on Saturday. The temperature will turn slightly cooler with highs on Saturday in the upper 50s to low 60s. With a partly cloudy sky, lows Sunday morning will range from the mid 30s across the Hill Country to the low 40s near the coast.
Forecast solutions indicate clouds off the eastern Pacific will spread northeast across Texas Sunday as an area of low pressure in the upper atmosphere sets up off the Mexican coast. Locally, our sky will become partly to mostly cloudy Sunday with high temperatures in the upper 50s to low 60s. A partly to mostly cloudy sky looks to continue Monday into Tuesday as the area of low pressure remains nearly stationary across western Mexico. A chance for rain is forecast to develop late Tuesday into Wednesday as the low pulls moisture north off the Gulf of Mexico. As of now, heavy rain is not anticipated. Temperatures next week are shaping up to be near normal with highs in the 60s and lows mostly in the 40s. The Jet Stream pattern next week is forecast to contain an unusually strong ridge of high pressure across the western US and a broad trough of low pressure across eastern Canada and the northeastern US. As of now, there are no signs of bitterly cold air breaking loose out of Alaska and heading south. However, this ridge/trough pattern has the potential to deliver colder air into the US over the next couple of weeks. It will be interesting to watch.
Bob
An Unsettled Pattern Late Week. Cooler Temperatures this Weekend and Next Week. MONDAY, JANUARY 30, 2012 05:59 PM [+] Click to view this entry
A mild weather pattern will hold in place throughout the week before cooler air arrives on Friday. Overall, temperatures look to trend a little cooler in early February. Today’s forecast data indicates we’ll see a slight chance for some light rain tonight and again on Wednesday as weak waves of low pressure track toward our region. A better chance for rain looks to develop Friday into early Saturday when a stronger trough of low pressure moves southeast out of the Rockies. This system has the potential to cause widespread rain totals of 0.5 to1 inch across much of Central and South Texas. Dry and cooler weather should follow Saturday through early next week.
Clouds spread across the southern half of Texas this afternoon due to a weak trough of low pressure tracking east out of northern Mexico:
The trough is pulling warm, moist air north over the cooler air at the surface, resulting in the development of clouds. A few spotty light rain showers have also developed and look to continue overnight and into Tuesday morning. But due to the lack of moisture and strong lift, rain amounts are forecast to only be around a tenth of an inch or less. Lows Tuesday morning will generally be in the mid and upper 50s. Some patchy fog will be possible after midnight across parts of Central Texas and the coastal plains region.
The threat for rain should end from west to east early Tuesday morning as the trough exits the region. The sky will likely stay cloudy till about midday then become partly cloudy in the afternoon. The temperature will be mild with highs generally in the low and middle 70s. A second, weak trough of low pressure in the upper atmosphere is forecast to track east out of the southwestern US late Tuesday into Wednesday. This system will pull clouds back over the region, resulting in a mostly cloudy sky beginning Tuesday night. There will be a very slight chance for a few sprinkles of light rain late Tuesday night into Wednesday morning as the trough tracks from northwest Texas into Oklahoma. Rain amounts, if any, will again be less than a tenth inch. Wednesday’s weather will start off cloudy with the sky becoming partly cloudy in the afternoon. Lows Wednesday morning will generally be in the upper 50s to low 60s while high temperatures Wednesday will be in the middle 70s. Drier air looks to spread south late Wednesday following the passage of the upper trough. This will cause temperatures to cool down a bit Wednesday night. Lows Thursday morning will include the mid and upper 40s Hill Country, the low to mid 50s central and near 60 degrees towards the coast. Thursday’s weather will be partly cloudy and dry with a high temperature in the low 70s.
Today’s forecast data indicates a broad trough of low pressure in the upper atmosphere will track southeast out of western Canada around the middle of the week. The trough is forecast to reach as far south as New Mexico and northwest Texas Friday, moving off to the northeast Friday night and Saturday. Increasing moisture and atmosphere lift are forecast across the region as this system digs to the south. As a result, conditions appear favorable for the development of widespread showers and a few thunderstorms beginning early Friday morning, continuing into Saturday morning. Today’s forecast data calls for significant totals of rain, but nearly as heavy as last week’s event. Most totals are forecast to be in the range 0.5 to 1 inch:
Dry and cooler weather is expected Saturday afternoon and Sunday, continuing into early next week. A dome of Canadian high pressure is forecast to spread south across Texas Saturday bringing cooler air. High temperatures Saturday and Sunday will be near 60 degrees. Lows Sunday morning will range from the mid 30s Hill Country to the low 40s near the coast.
Today’s forecast data indicates temperatures will stay slightly below normal next week. A large ridge of high pressure in the upper atmosphere is forecast to hold in place across the west, stretching north toward Alaska. At the same time, a large trough of low pressure is forecast to develop across eastern Canada, extending south to the Ohio Valley. With the Jet in this type of configuration, cold fronts will continue to spread southeast out of Canada toward the southern US. Therefore, temperatures next week will stay on the cool side. We’ll need to closely monitor this pattern over the next ten days to two weeks as much colder air could potentially spread southeast out of Alaska and northwest Canada. Some atmospheric indices seem to be pointing that direction at the current time. Stay tuned.
Bob
Weather Trending Dry and Mild Following Wednesday's Storm System THURSDAY, JANUARY 26, 2012 06:24 PM [+] Click to view this entry
The storm system Tuesday night was very unusual for late January. Not only was the severe weather out of season, the heavy rain was out of season as well. For much of Central and South Texas, the month of January is typically one of the driest, if not THE driest months of winter. But Tuesday’s night’s event proved otherwise. For example, the rain total of 5.66 inches on the 25th at Austin-Bergstrom Airport set a record for the most rainfall in a calendar day in January dating back to 1943. At the Austin-Camp Mabry reporting site, the 1-day total of 3.14 inches ended up being the 4th wettest January day dating back to 1892. The combination of very warm temperatures, an unusually moist air mass in the lower atmosphere and strong atmospheric dynamics combined to produce the unusually heavy rain.
The following National Weather Service graphic shows the distribution and amount of rain which fell between Tuesday and Wednesday. The data is a combination of radar estimates and surface gauge reports:
As you can see, the highest totals of rain fell across southeastern Travis, northwestern Bastrop, northeastern Guadalupe and Caldwell Counties. Parts of Fayette and Colorado Counties also saw some high totals. By the way, the highest gauged totals I found across the region were 9.29 inches 4 miles south-southeast of Uhland, in western Caldwell County and 9.35 inches at a gauge 2.4 miles northwest of Bastrop, in Bastrop County. Both of these reports are courtesy of the CoCoRaHS network. The highest LCRA gauged total was 7.09 inches at a location 3 miles west-southwest of Cedar Creek, in western Bastrop County.
The storm system responsible for our heavy rain and severe weather tracked to the east Wednesday night, reaching the Lower Mississippi Valley region today:
The sky cleared nicely across Texas as a dry, stable air mass spread across the region behind the storm system. This dry air mass will allow the temperature to cool down quickly tonight. Lows Friday morning will include the low and middle 30s across the Hill Country and the upper 30s to 40 degrees at most other locations. Friday’s weather will be sunny and mild. The return of southerly surface winds will boost afternoon readings in the upper 60s to 70 degrees.
A Canadian cold front currently located across the northwestern US is forecast to quickly track southeast tonight and Friday, moving across Texas Friday night. But with little atmospheric moisture in place, no rain is expected. The front looks to push off the coast around sunrise Saturday morning. The front will bring cooler air and cause breezy conditions on Saturday. High temperatures will range from the low 50s across the northern Hill Country to near 60 degrees near the coast. A light freeze looks likely across the Hill Country and much of Central Texas Saturday night. Lows Sunday morning will be near 30-32 degrees across the Hill Country, near 32-34 degrees across Central Texas and near 34-37 degrees across the coastal plains. Sunday’s weather is shaping up to be mostly sunny and mild with high temperatures near 60-62 degrees. Lows Monday morning will generally be near 40-42 degrees.
Our weather next week is shaping up to be dry and generally mild as the Jet Stream holds in place across the central Plains states. Monday and Tuesday’s weather will be partly cloudy. Highs will generally be in the low and middle 60s Monday and in the upper 60s to 70 degrees Tuesday. Lows will generally be in the upper 40s to low 50s. A weak Pacific cold front is then forecast to sweep across the region late Wednesday but the lack of moisture will preclude the development of rain. Wednesday will contain a partly to mostly cloudy sky with high temperatures near 70-72 degrees. Readings will turn slightly cooler Wednesday night with lows Thursday morning generally around 40-45 degrees. Thursday’s weather will be sunny with highs generally in the mid to upper 60s.
Today’s medium-range solutions indicate a deep trough of low pressure will develop across the central Plains late next week. The trough will cause a fairly strong Canadian cold front to push south, sweeping across Texas next Friday. Once again, no rain is expected due to limited moisture. However, this front does look to bring colder temperatures for next weekend. With a fairly strong area of high pressure tracking south to Texas, this front could bring a freeze to most locations next weekend and possibly into the early part of the following week. Today’s forecast data suggests the weather pattern will stay dry over the next ten day to two week period.
