230 FXUS64 KCRP 170730 AFDCRP Area Forecast Discussion National Weather Service Corpus Christi TX 230 AM CDT Sat May 17 2025 ...New SHORT TERM, LONG TERM, MARINE, FIRE WEATHER... .SHORT TERM... (Today through Sunday) Issued at 210 AM CDT Sat May 17 2025 Key Messages: - Major to extreme risk of heat-related impacts over inland Coastal Plains and Brush Country, moderate risk east - Moderate risk of rip currents this weekend Unseasonably warm temperatures, especially out west, will continue this weekend with highs peaking around 105 over the Rio Grande Plains and lows tonight in the mid to upper 70s. HREF/REFS probability of apparent temperatures reaching 110 or greater (Heat Advisory criteria) is less today than yesterday, with only a few splotches across the Brush Country and southern Coastal Plains containing a less than 20% chance. This guidance did well yesterday and therefore will continue to hold off on a Heat Advisory. However, there still remains a moderate risk of heat-related impacts over the Coastal Plains, and a major to extreme risk over the Brush Country as feels-like temperatures range from 100-110. Please continue to practice heat safety, limit outdoor exposure, take frequent breaks, and drink plenty of water. A mid-level shortwave stretching from North Texas to eastern Mexico combined with moisture pooling near the 99th percentile in front of a dryline provides an opportunity for showers and thunderstorms to develop west of the Rio Grande this afternoon. We'll have to closely monitor the progression of the shortwave and dryline but if any convection does linger into South Texas (20-30% chance) it would most likely be between 6pm - midnight tonight over the Brush Country. There is a greater chance where conditions are more favorable north into the San Antonio and Hill Country area. Storms originating in Mexico can struggle to maintain intensity into the Rio Grande Plains as we get further into the night and lose instability. && .LONG TERM... (Sunday night through next Friday) Issued at 210 AM CDT Sat May 17 2025 Key Messages: - Heat Risk remaining at Major/Extreme Monday, but decreasing from Tuesday. - Low chances (10-20%) for rainfall Wednesday along the Rio Grande. Out ahead of the upper-level trough that will move from the Intermountain West and into the Central Plains, a surface low will form over southern Colorado and slowly move eastward through the day. A front will extend south from this surface low through the Texas Panhandle and into the Edwards Plateau. Out ahead of this front, southerly winds will continue to feed Gulf-rich moisture. Temperatures Monday afternoon will continue to climb into the 100s across the relatively less-moist airmass over the Rio Grande Plains and into the 90s along the Coastal Bend and into the Victoria Crossroads. Heat indices Monday afternoon will span from the 110- 115F range across the Brush County and in the low 100s elsewhere, leading to a Major/Extreme Heat Risk. The aforementioned front will move through South Texas on Tuesday, with winds switching from a southeasterly direction to more easterly. PoPs do increase with the frontal passage, but unfortunately ensemble models continue to place much of South Texas in 10-15% PoPs. By Wednesday, a coastal trough will remain over northern Mexico and along the Mexican Gulf coastline. This zone of convergence and higher PWATs (1.7"-1.8") in the RGV will allow for showers to form along the Rio Grande and into the northern Mexican states. Webb County will be in the northern periphery of this area, thus giving them the best chance for precipitation 15-20% on Wednesday. That said, the NBM is still showing medium chances (30- 50% chance) of rainfall in excess of one hundredth for Laredo. Surface winds will continue to remain easterly through Thursday afternoon, allowing the Heat Risk to fall to Minor/Moderate. Thursday night, winds will switch to be more southeasterly, increasing heat indices back into the low 100s by Saturday. && .AVIATION... (06Z TAFS) Issued at 1044 PM CDT Fri May 16 2025 Aviation conditions will continue to deteriorate through the night to a mixture of MVFR/IFR levels due to low ceilings and patchy fog development. These poor aviation conditions will likely persist through the mid to late morning hours, before lifting back to VFR in the afternoon. Winds will become light overnight, but breezy conditions will return to the forecast by Saturday afternoon with gusts to 20-25 knots. Winds are forecast to the decouple by the evening hours on Saturday. && .MARINE... Issued at 210 AM CDT Sat May 17 2025 Moderate (BF 4) south to southeasterly winds will continue through tonight before increasing slightly to a moderate to fresh breeze (BF 4-5) Sunday with seas 4 to 5 feet. Moderate to fresh (BF 4-5) southeasterly winds will increase seas to 5-6 ft on Monday. Closer to the barrier islands, winds will gust up to BF 6 at times, resulting in choppy conditions over the inland bays. By Tuesday, winds will shift to be more easterly at gentle to moderate strength (BF 3-4) with seas decreasing to 3-4 ft by Thursday. Thursday night, winds will switch to be more onshore and increasing to moderate strength (BF 4). && .FIRE WEATHER... Issued at 210 AM CDT Sat May 17 2025 Minimum relative humidity this weekend will remain around 30% or greater, negating elevated fire weather conditions across South Texas. Surface southeasterly winds will only range from 10-20 mph as well. There is a low (20-30%) chance of showers and thunderstorms moving into the Brush Country from Mexico tonight. Energy Release Component is forecast to increase to above the 97th percentile immediately along the Rio Grande, while generally remaining above the 80th percentile across the Brush Country. Min relative humidity on Monday will bottom out to 15-20% across the Rio Grande Plains, and down to 10-20% on Tuesday with the frontal passage, while remaining in the 20-40% range across the Brush Country. Given this, an elevated fire risk will be contained to Webb County through Tuesday. From Wednesday, drier easterly winds will reduce Min RH's across the northern Brush Country and Victoria Crossroads to 20-30% through Thursday. 20-ft winds are looking to be weak across much of South Texas, limiting the fire risk through next weekend. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 91 78 90 78 / 0 10 0 0 Victoria 93 76 92 76 / 0 0 0 0 Laredo 104 78 104 80 / 0 30 0 0 Alice 99 76 97 77 / 0 30 0 0 Rockport 88 78 87 79 / 0 0 0 0 Cotulla 105 77 105 78 / 10 30 0 0 Kingsville 95 77 94 77 / 0 10 0 0 Navy Corpus 86 79 86 80 / 0 0 0 0 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...EMF/94 LONG TERM....AE/82 AVIATION...ANM/88