Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
245 FXUS64 KLIX 041119 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 619 AM CDT Thu Sep 4 2025 ...New AVIATION... .SHORT TERM... (Today through Friday) Issued at 1201 AM CDT Thu Sep 4 2025 Axis of the upper ridge to the west extended from near El Paso to Seattle Wednesday evening, with another ridge well to the east near Bermuda. A large upper low was over Lake Superior, with the axis of the upper trough just to our east. One shortwave was moving through the base of the trough, with another over Iowa or Missouri. Most of the afternoon convection that was approaching our area had dissipated, but isolated convection was noted over Mississippi between Jackson and Memphis. There were also some mid-level clouds that could occasionally make skies partly to mostly cloudy for a brief time. Late evening temperatures were mainly in the 70s with dew points between 68 and 73. Moisture levels were slightly higher Wednesday evening than earlier anticipated, with precipitable water values near 1.7 inches, which helps explain the mid-level clouds. The upper ridge to the west is expected to break down somewhat, as a strong shortwave wraps around the upper low near Lake Superior. This will actually produce somewhat of a zonal upper flow over the northern Gulf Coast for Friday, with a bit more onshore flow. We will see some minor drying of the column for the next 36 hours or so with precipitable water values around 1.5 inches or maybe a bit less. May see some cumulus this afternoon, with bases around 5,000-6,000 feet, but don`t anticipate any significant precipitation. And Friday looks pretty much like a repeat, although with a bit of onshore flow. That might nudge dew points up a degree or two, but still not oppressive conditions. High temperatures should top out between 90 and 95 for most of the area, with overnight lows upper 60s to mid 70s. && .LONG TERM... (Friday night through Wednesday) Issued at 1201 AM CDT Thu Sep 4 2025 Main question for the early portion of the extended period is how much East Pacific Hurricane Lorena disturbs the upper pattern that has been almost a semi-permanent fixture across the area recently. With the surface high that has been to the east of the area slides a bit further east, that should allow weak onshore flow to continue with moisture levels creeping up a bit Saturday and Sunday to near climatologic normals for September. The 03/12z and 18z runs of the ECMWF and GFS really backed off on expected moisture levels for late in the weekend and early next week, and this was reflected in lowered chances of precipitation. In fact, the WPC 7 day QPF forecast from Wednesday afternoon indicated that most of the area should expect less than one half inch of rain. Anything more than that would likely be limited to coastal locations. The most favored day for precipitation would be Sunday with a frontal passage associated with a northern stream shortwave moving through the Ohio River Valley, but even then, we`re talking probably less than 50 percent, even at the coast. The one thing the frontal passage Sunday may do, is introduce a surge of drier/cooler air to portions of the area for a day or two early next week before moderating again. Much of the area could have a day or two with highs in the 80s and lows in the 60s, before moderating back toward climatologic normals. Ensemble means from both the GFS and ECMWF from Wednesday are surprisingly lacking in precipitation. We`ll see how that plays out as we head through the next week or so. && .AVIATION... (12Z TAFS) Issued at 619 AM CDT Thu Sep 4 2025 VFR conditions through this taf cycle. && .MARINE... Issued at 1201 AM CDT Thu Sep 4 2025 A surface high will settle over the waters today. Winds should be rather variable through Saturday and seas will run around 1 foot. Heading into next week, another frontal passage Sunday or Monday will bring an increased pressure gradient to the waters, potentially exceeding 15 knots over the open waters by Monday afternoon. Seas will respond to these stronger winds and increase into the 2 to 3 feet range. && .PRELIMINARY POINT TEMPS/POPS... MCB 90 70 92 71 / 10 0 0 0 BTR 93 72 94 73 / 10 0 0 0 ASD 90 71 91 71 / 10 0 0 0 MSY 93 75 94 76 / 10 0 0 0 GPT 89 73 90 72 / 10 0 0 0 PQL 90 71 91 70 / 10 0 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...RW LONG TERM....RW AVIATION...TE MARINE...RW