FXUS64 KHGX 270435 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1135 PM CDT Fri Jul 26 2024 ...New AVIATION... .SHORT TERM... (This evening through Saturday Night) Issued at 246 PM CDT Fri Jul 26 2024 The heavier rains of this morning have yielded to a "cool" and cloudy afternoon featuring scattered showers. Temperatures are fighting to surpass 80 degrees in some areas. A typical late July afternoon ranges from low 90s near the coast to mid/upper 90s inland. So the mid 70s to low 80s we are experiencing today could be described as "cool" in relative terms. Perhaps we will establish a few record low max temperatures today. The current shower activity is expected to diminish as the late afternoon progresses into the evening. A well defined mid/upper trough can be seen over Texas via WV imagery and 500MB RAP analysis. SE Texas is located between the trough to our west and a mid/upper ridge over Florida. Moist Tropical Pacific oriented SW flow aloft between the two features is pushing a continuous stream a mid-level shortwaves up the Texas Coast. These features in the upper-levels combined with deep LL tropical moisture and some modest instability will keep the chance of scattered to widespread showers and thunderstorms in the forecast for your Saturday. Models indicate increasing PVA tonight into tomorrow morning. However, there is some disagreement on the timing of when lift becomes sufficient for shower/thunderstorm development. Global models suggest we could have showers/storms develop across our coastal counties as early as midnight. But hi-res CAMs guidance suggest it may take until the pre-dawn hours before we begin to see showers and thunderstorms develop. Though most of the CWA has a shot at receiving rainfall on Saturday, the best chance of receiving moderate to heavy showers and thunderstorms will be across our southern and coastal counties during the morning hours. Considering the saturated antecedent soil conditions, we have opted to extend the Flood Watch through early afternoon tomorrow across our southern and coastal zones. Saturday afternoon may end up like today with overcast skies and scattered residual showers. Afternoon highs are expected to be in the low/mid 80s. But we cannot rule out some areas struggling to reach 80 again due to rainfall. The pattern eventually becomes hotter and less rainy. But I'll leave that part of the discussion to the long range forecaster. Self && .LONG TERM... (Sunday through next Thursday) Issued at 246 PM CDT Fri Jul 26 2024 The transition to a more typical summertime pattern will begin on Sunday as the robust midlevel trough in place across the South Central CONUS will finally begin to shift to the northeast. Steady rainfall should begin to taper off on Sunday morning as this occurs, and over the course of the day broad surface high pressure will once again become situated across the Eastern Gulf. The resultant onshore flow regime promoted by this pattern, along with the presence of a mid/upper ridge that will build into the central third of the country by Monday morning, will result in decreased rainfall chances over the course of the upcoming week given the lack of available synoptic forcing. Rainfall chances through mid- week will be confined mainly to diurnal heating, as well as the inland propagation of the sea/bay breezes each afternoon. Have generally maintained 20-40% PoP values in this forecast package, with the highest rain chances concentrated along and south of the Interstate 10 corridor. Rain chances decrease further towards the end of the week with high pressure solidly overhead. As one may expect with the transition to a more typical summertime pattern, temperatures will steadily increase heading into next week with highs returning to more normal values (mid-90s). With onshore moisture transport once again keeping dew points elevated, we could be looking at Heat Index values near 110 and thus will need to monitor for the potential for Heat Advisories during this time. && .AVIATION... (06Z TAF Issuance) Issued at 1103 PM CDT Fri Jul 26 2024 Not a lot on radar at this time, but near-term models are indicating that we could see another round of showers/thunderstorms through the overnight period with the passage of another shortwave (from the SW) on a seemingly similar track like last night. For now, only going to make some tweaks to the current timing...mainly to start things up a bit sooner (by an hour or two). This messy active pattern should per- sist into Sat afternoon before coverage decreases by Sat evening. Un- fortunately, models are indicating yet another shortwave moving into the area from SW Sat night/Sun morning. 41 && .MARINE... Issued at 246 PM CDT Fri Jul 26 2024 Periods of rain, heavy at times, will impact the coastal waters on both Saturday and Sunday during the earlier parts of the day. Any stronger storms may produce strong wind gusts and locally elevated seas. Rainfall chances diminish on Monday as high pressure settles into the area, promoting the return of a steady onshore flow regime. Winds and seas should generally remain below caution thresholds over this time. Cady && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 73 83 73 87 / 40 40 20 60 Houston (IAH) 74 83 75 87 / 50 70 40 70 Galveston (GLS) 76 86 80 86 / 60 70 50 60 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Flood Watch through Saturday afternoon for TXZ200-213-214-226- 227-235>238-300-313-335>338-436>439. GM...None. && $$ SHORT TERM...Self LONG TERM....Cady AVIATION...41 MARINE...Cady