


Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
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895 FXUS64 KLCH 101806 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 106 PM CDT Sun Aug 10 2025 ...New SHORT TERM, LONG TERM, AVIATION, MARINE, FIRE WEATHER... .KEY MESSAGES... - An easterly wave/inverted trough feature will continue to move west across the northern Gulf into Texas through mid-week helping to increase rain chances over the area, especially near the seabreeze boundary. - A surge of deeper more tropical like moisture will move around the wave and into eastern portions of forecast area proving a risk of excessive rainfall on Tuesday into Wednesday. - The subtropical ridge from the east will build in at the end of the week to provide typical summertime weather. && .SHORT TERM... (Tonight through Tuesday night) Issued at 103 PM CDT Sun Aug 10 2025 Conditions are relatively quiet over the forecast area at the moment. There was a healthy amount of nocturnal convection over the Gulf this early morning, with some of the convective blow off and stratiform rain moving inland, especially over lower Acadiana, and this has somewhat delayed daytime heating and kept the instability in check. Also with east-northeast flow seen on the VAD at KLCH up to 10k feet, the seabreeze has been kept down at the coast. You can see mainly a cyclonic motion of clouds and showers over the forecast area from the inverted trough/easterly wave located off the Louisiana coast. GOES data shows PWAT increasing to near 2 inches near the coast and over eastern portions of the forecast area. Would expect a few showers and thunderstorms to begin to develop by 3 pm as air temperatures reach the low 90s. The best chance will be I-10 and to the south as seabreeze will likely not make much progress to the north this afternoon. For the next couple of days, a weakness will be provide by the inverted trough feature as it meanders to the west. By late tonight into Monday, PWAT near or above 2 inches with mean layer relative humidity over 70 percent is expected to invade the forecast area. Therefore, a better chance of showers and thunderstorms is expected on Monday. Guidance shows that an early start is also possible for southern areas as a decent amount of nocturnal convection is expected again, however a slightly more southeast component aloft will help the activity have a better chance of moving inland. By Tuesday, a swath of highly anomalous and tropical like air on the western edge of the subtropical ridge will be entrained into the inverted trof feature allowing for a significant jump in moisture values, especially for lower Acadiana. PWAT for lower Acadiana and the Atchafalaya Basin is projected to increase to over 2.25 inches, which is will over the 90th percentile, and mean layer relative humidity values over 80 percent. So convection that develops in that portion of the forecast area will have the potential to be efficient precipitation producers. With that potential for high rainfall rates, a Marginal Risk (level 1 out of 4) for excessive rainfall that may lead to flash flooding will be outlined for lower Acadiana and the Atchafalaya Basin. Rua && .LONG TERM... (Wednesday through next Saturday) Issued at 1250 PM CDT Sun Aug 10 2025 The highly anomalous moisture on the east side of an inverted trough will continue to be pushed into the forecast area on Wednesday as the subtropical ridge begins to build in from the east. Projected PWAT values are over 2.25 inches and above the 90th percentile with mean layer relative humidity over 80 percent. With the weakness aloft and daytime heating working with the moisture expect a decent chance for showers and thunderstorms especially during the afternoon hours and near the seabreeze boundary. With the high moisture content, the showers and storms will have the potential to be some torrential downpours and therefore a Marginal Risk (level 1 out of 4) of excessive rainfall will be outlined for eastern portions of the forecast area. By Thursday, the subtropical ridge will begin to build into the forecast area and will continue to expand into the forecast area during the end of the week. This will provide typical summertime weather with hot and humid days, muggy night, and scattered afternoon showers and thunderstorms. Rua && .AVIATION... (18Z TAFS) Issued at 1243 PM CDT Sun Aug 10 2025 VFR conditions currently at the terminals. Expect cu to continue to develop during the afternoon hours with daytime heating, although ceilings are expected to remain at VFR levels. Scattered showers and a few thunderstorms are expected to form by max heating, so will mention VCTS at terminals after 10/20z. Convection is expected to dissipate with the loss of daytime heating by 11/02z with fair and stable conditions during the night. Outside chance of some patchy light fog toward sunrise, however will keep all terminals at VFR at this time. Rua && .MARINE... Issued at 1239 PM CDT Sun Aug 10 2025 A weak pressure pattern over the northwest Gulf will help provide mainly light winds and low seas into early next week. A weak surface high will ridge into the coastal waters from the east by Wednesday providing mainly light onshore winds. An inverted trough over the northwest Gulf will increase the chance for showers and thunderstorms over the coastal waters during the period. && .FIRE WEATHER... Issued at 1236 PM CDT Sun Aug 10 2025 A weakness moving across the northwest Gulf will help increase moisture over the area early next week. Rain chances will increase with mainly afternoon showers and thunderstorms. Afternoon minimum relative humidity values will be over 50 percent on Monday and over 60 percent by Tuesday. && .PRELIMINARY POINT TEMPS/POPS... AEX 74 93 73 92 / 20 50 20 60 LCH 76 92 76 91 / 40 70 40 70 LFT 76 91 75 90 / 30 70 30 70 BPT 76 91 76 92 / 30 60 30 60 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ SHORT TERM...07 LONG TERM....07 AVIATION...07