Welcome to summer! Over the past week, the weather pattern across Texas quickly transitioned from spring to summer as a broad ridge of high pressure set up over the state. The combination of high temperatures around 90 degrees and very humid air spreading north from the Gulf has made weather conditions feel much more like late June rather than the middle of May. And long-range forecast solutions indicate the current hot and humid pattern is likely here to stay, with no additional shots of cool air coming our way through the end of the month. So even though the calendar says summer won't officially begin until June 21st, in reality, it's already here.
Monday's weather maps showed a broad, stable ridge of high pressure in the upper atmosphere stretching from Central Texas to the Tennessee Valley. The ridge was causing a dry, stable and very summer-like weather pattern across the eastern two-thirds of the state. Meanwhile, a broad trough of low pressure is currently in place across the western US. Weak disturbances rotating around the trough are moving across New Mexico and the Texas Panhandle, helping to fire scattered thunderstorms along the West Texas dry line. This pattern is forecast to hold through Wednesday, before the ridge of high pressure spreads back to the west, ending the development of West Texas thunderstorms.
Midday satellite images showed considerable clouds covering much of South and Central Texas due to one of the passing disturbances moving across West Texas. These clouds were not producing any rain and none is forecast this afternoon across Central Texas or the middle Texas coast. However, expect the sky to stay mostly cloudy sky this afternoon and tonight. Today's temperature is predicted to warm close to 90 degrees. There will be a slight chance for a couple of scattered thunderstorms spreading into parts of the western and northern Hill Country out of West Texas late this afternoon and evening. The probability for rain will only be 20 percent.
For Tuesday and Wednesday, expect widespread nighttime and morning clouds giving way to a mostly sunny sky in the afternoon. No rain is forecast across the eastern Hill Country, Central Texas or the middle Texas coast. However, there will be 20 percent chance for late afternoon and evening thunderstorms across the western and northern Hill Country. Rain amounts, if any, should total around a quarter inch, or less. High temperatures both days will be in the low 90s. Low temperatures will be in the low 70s. The wind will be fairly light both days, with south winds in the range of 5-10 mph.
For Thursday and Friday, expect mostly sunny, dry and even warmer weather as the center of the high pressure ridge sets up directly over Central Texas. High temperatures both days are forecast to generally be in the middle-90s. A few spots across the Hill Country and Central Texas could even see readings reach the upper 90s.
No significant change in the weather is predicted for Central and South Texas this coming weekend. The center of the high pressure ridge is forecast to move from Central Texas to the lower Mississippi Valley. This should cause high temperatures to drop back to the low-90s at most locations. Forecast solutions do call for a weak Canadian cold front to sink south from the southern Plains states into North and Northwest Texas on Saturday. The front is forecast to stall well north of Central Texas. This boundary could led to the development of a few scattered thunderstorms across the northern Hill Country late Saturday.
Looking ahead to next week, mostly sunny and hot weather conditions look to continue. There are some indications we may see a slight chance for rain develop the latter part of the week when another large trough of low pressure sets up over the western and Southwestern US, bringing occasional disturbances into Texas. High temperatures are forecast to be mostly in the low 90s.Early-Season Tropical Disturbance Over the Eastern Gulf of Mexico
A deep-layer non-tropical area of low pressure located over the eastern Gulf of Mexico continues to produce widespread cloudiness, showers, and thunderstorms across much of Florida and southeastern Georgia. Although this system could still acquire some subtropical or tropical characteristics while it moves slowly northward across the eastern Gulf of Mexico during the next few days, the low has not shown signs of increased organization during the past 24 hours. Regardless of subtropical or tropical cyclone formation, this system will produce locally heavy rainfall and possible flash flooding across portions of Florida and the southeastern United States during the next few days. National Hurricane Center forecasters are giving this system a 20 percent chance for development over the next 48 hours and a 30 percent chance for development over the next 5 days.
This system poses no threat to Texas as it is being pulled to the north-northwest by a trough of low pressure moving across the Tennessee Valley.
RAMMB – CIRA 2:15 pm CST 05/14/2018