Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
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595 FXUS64 KLCH 150313 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 1013 PM CDT Fri Jun 14 2024 ...New UPDATE... .UPDATE... Issued at 1005 PM CDT Fri Jun 14 2024 A small cluster of thunderstorms has formed late this evening near Vermilion Bay and Saint Mary/New Iberia Parishes, moving west. This activity is expected to be short-lived as it moves over western portions of Vermilion and West Cote Blanche Bays into eastern Vermilion Parish. Other than adding some low PoPs in this area and making some minor adjustments to hourly temps and winds for this evening, the current forecast is on track with generally quiet conditions expected through Saturday as high pressure prevails aloft. 24 && .SHORT TERM... (Tonight through Sunday night) Issued at 252 PM CDT Fri Jun 14 2024 The short term will be a period of transition as the current dry air mass departs. A ridge aloft and high pressure at the surface is across the deep south this afternoon with a very dry air mass in place locally. PWAT on this morning`s KLCH sounding was 0.83" which is near the daily min for the date. This dry air mass has kept most cloud cover sparse and allowed temps to rise into the 90s which is a few degrees above normal for the date after a somewhat cool morning. Through tonight and Saturday the ridge will shift east toward the Atlantic coast. An inverted trough that extends southwest from Florida into the Yucatan will begin to move west around the base of the ridge. Higher moisture will begin to work into the local area as the trough moves farther into the gulf. Saturday is anticipated to be dry once again, however dewpoints are expected to remain higher then nudge upwards through later Saturday and through the night. A few showers will begin to the return to the coastal waters Saturday night with scattered convection working into the area Sunday, but mainly late in the day. Moisture will increase during the day Sunday. PWAT values will increase to over 2" along the coast of LA by sunset Sunday and may increase to near the daily max for the date in Lower Acadiana. This will occur as the inverted trough slowly moves west across the gulf and central America. The local area will be on the northern fringe of the trough with moisture being pulled northwest around the edge of the departing ridge and setting the stage for a wet extended period. && .LONG TERM... (Monday through next Thursday) Issued at 252 PM CDT Fri Jun 14 2024 Looking like a wet period for the early to middle part of next week. The upper level ridge over the northwest Gulf will diminish with the upper level ridge becoming centered over the southeast US and off the coast. This will develop a broad east to west wind flow across the Gulf of Mexico, and this will push the inverted trough and associated deep tropical moisture that has been over the northwest Caribbean into the Florida area to the west. The deep moisture and trough will reach the forecast area by the beginning of the period on Monday then push it gradually west through Thursday. Currently, the most likely scenario is for the inverted trough axis to stay on the weak side, or if it does develop into a more closed off cyclone, for the closed low to stay well south of the forecast area and across the southern Gulf of Mexico. Just how closed off or strong the low gets will impact how much of the deep moisture stays over the forecast area. For now, will keep the scenario of basically just a sloppy weak trough feature. The air mass will definitely have a tropical origin with highly anomalous moisture values. Precipitable Water values will range from 2.2 to 2.4 inches which is well above the 90th percentile for this time of year of around 2 inches, and closer to max moving averages and daily highs. Also, 1000-500 mean layer relative humidity values will be over 80 percent and warm cloud layer will be between 13k-15k feet, which all means that convection will be highly efficient warm process rain makers. Usually in these air masses, plenty of nocturnal activity occur over the Gulf and right along the coast, and with low convective temperatures, this activity will spread quickly inland during the day. Reliable QPF numbers show total rainfall amounts from Monday through Wednesday averaging 3-6 inches from along and south of the I-10 corridor, and 1 to 3 inches north of the I-10 corridor. Of course, there could be some locally higher amounts, but way too soon to pinpoint any of that. With the expected rainfall, Marginal to Slight Risk of Excessive Rainfall (level 1 and 2 out of 4) that may lead to flooding has been outlined for the Day 4 and 5 periods which is Monday and Tuesday. This outlooks will probably be refined over the next few days and will probably have to be extended into Wednesday also. Any other impacts will be breezy conditions for right along the coast and offshore with building seas and swells, to go along with some higher than normal tides. If there is some good news, although it will be muggy, high temperatures should be a little below normal during the period. 07/Rua && .AVIATION... (00Z TAFS) Issued at 626 PM CDT Fri Jun 14 2024 FEW/SCT CU near the Acadiana terminals will dissipate over the next few hours, with SKC to prevail overnight. No significant changes are expected through the period, with light/variable winds tonight becoming E-SE 4-8 KT in the afternoon with FEW-SCT CU again developing. 24 && .MARINE... Issued at 252 PM CDT Fri Jun 14 2024 Light winds and low seas will continue into Saturday, however the pressure gradient will tighten Sunday into early next week. Winds and seas will build Sunday through mid week as an inverted trough passes to the south. SCA conditons are anticipated Monday night through Thursday. Tides are also expected to run above normal and minor coastal flooding may be a concern at times of high tide. && .PRELIMINARY POINT TEMPS/POPS... AEX 69 96 72 95 / 0 0 0 20 LCH 74 95 74 93 / 0 10 0 40 LFT 75 97 76 93 / 0 10 0 60 BPT 74 95 75 93 / 0 0 0 30 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ SHORT TERM...05 LONG TERM....07 AVIATION...24