997 FXUS64 KLCH 151759 AFDLCHArea Forecast Discussion National Weather Service Lake Charles LA 1259 PM CDT Mon Sep 15 2025
...New SHORT TERM, LONG TERM, AVIATION, MARINE, FIRE WEATHER...
.KEY MESSAGES...
- Upper low over the southeastern US will help keep cloud cover in place through the midweek. The relative weakness developing aloft and moisture moving inland Tuesday could bring scattered afternoon showers.
- Temperatures should hold steady in the low 90s through the forecast period. This is still above normal temps by 2 to 3F.
- Lower than normal daytime humidity will keep heat indices capped in the upper 90s to around 100 each day.
&&
.SHORT TERM... (Tonight through Wednesday night) Issued at 1259 PM CDT Mon Sep 15 2025
Pattern is starting to turn over, as is evident by regional cloud cover, thin as it may be. 18z RAOB is rather indicative of this moist cloud layer around 800 mb with a mixed surface and dry air still very present aloft. Also very present aloft and in water vapor imagery is the upper low spinning over the Carolinas. This upper low is progged to amplify and meander westward in the coming day, clearing off any upper ridging in the area. While some high pressure influence will be present Tuesday and Wednesday, enough instability may be generated by a northward advancing wave of moisture to generate a few scattered showers with isolated embedded thunderstorms. Not anticipating any rain-outs either day as PWATs in the 1.55 to 1.70 inches range are forecast. To give some context, the median climatological PWAT for 9/16 is ~1.55 inches. To see any meaningful gully washer, a PWAT closer to or above the 90th percentile (~2.05 inches) is needed.
This increase in cloud cover will also assist with keeping highs somewhat in check each day. Highs in the lower 90s can be anticipated with daytime heat indices in the mid 90s.
11/Calhoun
&&
.LONG TERM... (Thursday through next Sunday) Issued at 1259 PM CDT Mon Sep 15 2025
Pattern really livens up looking to the end of the work week. SE US upper low lifts out late Wednesday and another upper trof drops out of the Rockies before ridging can set back in on Thursday. Heights will briefly rise Thursday simply between these two features, so rain chances do falter slightly. By Friday and the weekend, a series of lows will roll through the southern end of the trof traversing the US, resulting in a few waves of scattered showers and embedded thunderstorms.
Guidance begins to differ towards the end of the longterm period, but global flow is showing signs to indicate a meridional pattern may be setting up towards the end of September. We will continue to monitor.
Daytime temps will remain above climo normals (normal is roughly 89F) with highs in the lower 90s. So, much of the same as in days previous.
&&
.AVIATION... (18Z TAFS) Issued at 1259 PM CDT Mon Sep 15 2025
Upper level ridge is beginning to erode which is evident by an increase in cloud cover and some very isolated area showers.
Rain chances are low enough not to include mentions of convection at terminals. However, MVFR range clouds may linger into the early evening.
It`s possible to have another round of patchy morning fog, but not very likely.
11/Calhoun
&&
.MARINE... Issued at 1259 PM CDT Mon Sep 15 2025
Winds and seas will generally remain low through the period. There may be brief periods of outer waters enhancing to 2 to 3 ft as easterly flow increases on passing waves. Rain chances also increase from the south later in the period as upper level patterns become a bit more active.
&&
.FIRE WEATHER... Issued at 1259 PM CDT Mon Sep 15 2025
High pressure starts to erode today into the coming days allowing for the return of moisture. Daytime RH values in the 45 to 55 percent range can be expected in coming days.
Weakness and daytime heating will also allow for the return of low end rain chances Tuesday and again Wednesday.
&&
.PRELIMINARY POINT TEMPS/POPS... AEX 92 69 93 69 / 10 0 20 10 LCH 91 72 93 72 / 20 0 20 10 LFT 91 72 91 70 / 10 10 20 10 BPT 91 71 92 72 / 20 0 20 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. &&
$$
SHORT TERM...11 LONG TERM....11 AVIATION...11
NWS LCH Office Area Forecast Discussion