


Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
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205 FXUS64 KHGX 141944 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 244 PM CDT Wed May 14 2025 ...New SHORT TERM... .SHORT TERM... (This evening through Thursday Night) Issued at 215 PM CDT Wed May 14 2025 Hot, summer-like weather should continue over the next few days, courtesy of a mid/upper level ridge currently near Mexico and the western Gulf of America. A 850mb low/trough to the west with high pressure to the east has established a weak LLJ today, only in the range of 20 to 30 knots out of the the southwest. HREF places mean 850mb T advection broadly at 1-2 K/HR with mostly clear skies and dewpoints mixing into the 60s this afternoon. NAEFS has 850mb temps over the 99.5th climatological percentile for this time of the year, with the ECMWF EFI at 0.5-0.99 and SoT > 0 in spots. Spatially, the signals for heat stress are broadly strongest further northwest. The Heat Risk threat is currently high (level 4/5) for today, highlighting the anomalous warmth for this time of the year (typically in the mid/upper 80s) though WBGT values suggest high heat stress to be more focused over the northwestern counties. With this in mind, Heat Advisory remains in effect through through 7 PM tonight for areas across the Brazos Valley. Thursday broadly looks the same with only some specific differences to note. 500mb Heights rise slightly as the center of the midlevel high shifts over the western Gulf of America. The 850mb low/trough pushes eastward, tightening the pressure gradient and strengthening the LLJ to 30-45 knots. While 850mb temperatures are forecasted to be slightly weaker (NAEFS 850mb T above the 97.5th percentile), the strengthened LLJ should amplify WAA, with the HREF showing temp advection reaching 1.3-4.0 K/hr at times. HREF dewpoints suggest slightly less mixing, perhaps as a result of the strong temperature advection invigorating the cap/amplifying subsidence, though drier air underneath the cap and the strengthened LLJ would suggest that dewpoints still mix into the 60s during the afternoon. In layman`s terms, it`s going to be hot with highs in the upper 80s to upper 90s during the afternoon with morning lows in the mid/lower 70s. The tricker question remains just how dangerous this heat is. As already mentioned, these temperatures are very warm for this time of the year, and early-season heat can be especially stressful since the body needs time to get acclimated to hot summer temperatures. At the same time, dewpoints mixing out during the afternoon with gusty winds should alleviate the effects of heat. For this reason, I`ve opted to hold off on issuing a Heat Advisory for Thursday. As a reminder, heat is still the #1 weather-related killer in the U.S. With climatological summer approaching, practicing good heat safety will be important for those planning to spend extend amounts of time outside. Drink plenty of fluids and avoid strenuous outdoor activities during the hottest part of the day. Wear lightweight and loose fitting clothing when possible. Stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Know the signs and symptoms of heat exhaustion and heat stroke. 03 && .LONG TERM... (Friday through next Tuesday) Issued at 101 PM CDT Wed May 14 2025 SE Texas will find itself under the influence of a large, deep subtropical ridge through the duration of the long term forecast period. Thus, the hot pattern that is blessing us with its presence in the short term will continue into the long term. Though the ridge will be relatively well stacked, the center of the ridging is expected to be farther east in the lower levels, allowing for continued deep LL southeasterly flow from the Gulf. This will keep conditions relatively humid. So expect more afternoons in the 90s with heat index values over 100. Coastal areas are expected to be in the mid/upper 80s. Area-wide overnight lows will generally be in the 70s. In terms of hazardous heat, the primary concern is near the beginning of the long term, where high temperatures coupled with high humidity and lower winds will likely enhance the risk associated with the heat. As we head into early next week, subtle changes in the LL pattern may result in increasing southeasterly winds, which would reduce (though not eliminate) the heat`s associated health risk. Regardless, the long term is very hot, especially for May. PLEASE remember to practice heat safety precautions. Self && .AVIATION... (18Z TAF Issuance) Issued at 1231 PM CDT Wed May 14 2025 VFR conditions and gusty south/southwest winds are expected throughout the rest of the daytime. Wind gusts should diminish this evening with MVFR CIGS slowly filling in from the coast overnight into Thursday. During this time frame, a low level jet will strengthen, bringing wind shear from strong southwest winds of 35-45 knots around 2000 feet. This jet & wind shear will be most prominent over the northern TAF sites, though wind shear groups may be expanded to include southern terminals. Gusty winds resume Thursday morning as CIGS clear and wind shear weakens. 03 && .MARINE... Issued at 101 PM CDT Wed May 14 2025 South to south-southeast winds are expected to increase again overnight and into Thursday morning. Gusts over 30 knots will be possible once again. These winds are expected to decrease somewhat again as we head into Thursday afternoon, with a Small Craft Advisory in effect through Thursday. That being said, hazardous winds and especially seas may continue into Friday. Winds and seas should decrease on Friday into Saturday as the gradient eases. The gradient may steepen again early next week, bringing another chance of increasing southeast winds and seas. Self && .CLIMATE... Issued at 312 AM CDT Wed May 14 2025 With multiple days of near-record to record-breaking heat expected over the upcoming week, here`s a look at the daily high temperature records through Monday (May 19th). May 14th High Temperature Records --------------------------------- - College Station: 96F (1925) - Houston/IAH: 93F (2018) - Houston/Hobby: 93F (1961) - Palacios: 91F (2024) - Galveston: 90F (2024) May 15th High Temperature Records --------------------------------- - College Station: 95F (1925) - Houston/IAH: 94F (2018) - Houston/Hobby: 94F (1978) - Palacios: 93F (1943) - Galveston: 89F (2022) May 16th High Temperature Records --------------------------------- - College Station: 95F (2003) - Houston/IAH: 94F (2022) - Houston/Hobby: 94F (2022) - Palacios: 88F (2010) - Galveston: 90F (2022) May 17th High Temperature Records --------------------------------- - College Station: 96F (1925) - Houston/IAH: 96F (2018) - Houston/Hobby: 94F (2018) - Palacios: 93F (2003) - Galveston: 90F (2020) May 18th High Temperature Records --------------------------------- - College Station: 98F (2022) - Houston/IAH: 95F (2022) - Houston/Hobby: 94F (2022) - Palacios: 89F (2022) - Galveston: 90F (2022) May 19th High Temperature Records --------------------------------- - College Station: 94F (2022) - Houston/IAH: 95F (2003) - Houston/Hobby: 94F (2008) - Palacios: 89F (2024) - Galveston: 90F (2022) Batiste && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 72 97 76 96 / 0 0 0 0 Houston (IAH) 74 96 77 95 / 0 0 0 0 Galveston (GLS) 76 86 77 86 / 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Heat Advisory until 7 PM CDT this evening for TXZ176-195>198. Beach Hazards Statement through Thursday evening for TXZ436>439. GM...Small Craft Advisory until 1 PM CDT Thursday for GMZ330-335-350- 355. Small Craft Should Exercise Caution from Thursday afternoon through Thursday evening for GMZ330-335-350-355. Small Craft Advisory until 7 PM CDT Thursday for GMZ370-375. && $$ SHORT TERM...03 LONG TERM....Self AVIATION...03 MARINE...Self