Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
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246 FXUS64 KLIX 280453 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1153 PM CDT Mon May 27 2024 ...New AVIATION... .SHORT TERM... (This evening through Tuesday night) Issued at 340 PM CDT Mon May 27 2024 After a hot and generally dry Memorial Day weekend, temperatures will be trending back down some. Although we likely won`t get down to normal temps, at least shouldn`t be flirting with record highs. These cooler temps come thanks to an upper level trough that`s pushing south out of Canada. The first of a few embedded shortwave troughs is now passing across the Ohio Valley. The frontal boundary associated with the trough isn`t cold but definitely a bit drier. Locally today, still watching seabreeze convergence boundaries for afternoon convective potential. Best chance through the next few hours will probably be in SELA along/south of Lake Pontchartrain. Earlier some activity tried to get going but the CAP aloft knocked them down pretty quickly. Did notice a gravity wave in SW LA racing eastward. Although timing would have to be perfect for this feature to help spark convective initiation, it bears watching. Moving into Tuesday, shortwave trough will help to drive the parent upper trough farther south across the southeastern US on Tuesday. This will bring the associated frontal boundary closer to the CWA. Even though 500mb heights locally will be lowering as the ridge that`s kept the area to hot lately suppresses, compressional warming will keep highs in the mid 90s just one more day. Much like today, the potential continues for late afternoon convection with more than ample instability aloft. Very conditional threat with CAP aloft. After than, finally start cooling things down on Wednesday with near normal temps for the first time in what seems like awhile. && .LONG TERM... (Wednesday through Sunday night) Issued at 340 PM CDT Mon May 27 2024 The medium range still has a number of uncertainties but the main one is the strength of the L/W trough over the eastern 3rd of the CONUS by Thursday. A slightly deeper trough is promoting a better chance of seeing moderate northwest flow aloft. 2nd is what ever disturbance being advertised in the southern Plains and E Texas is actually there and able to continue to work down the northwest flow. Pretty large discrepancies when looking at the models with the the ECMWF and its ensemble mean being the drier and warmer solution while the GFS/GFES/GEM/GEPS favor a slightly cooler and wetter fcst. This split has been the case for the past 48 hours and the NBM appears to be putting a little more weight in the cooler/wetter side. Right now with nothing to really grasp will stick closer to the NBM and see if we can get a better idea in the next 24-36 hours. Thursday and Friday at this time could be much nicer than what we have seen today and what is expected tomorrow. We should have a little more northwest flow aloft Thursday and perhaps into Friday and it looks like we will see overnight convection decaying to our west and northwest with decent cloud cover blowing off over the area. Also there is some indication that we could see possibly a backdoor style cold front (well compared to the mid 90s of today and Tuesday) much of the guidance is suggesting highs in the upper 80s to near 90. Combine that with the possibility of rain and decent cloud cover and mid 80s is possible. The biggest question is can we get convection. A lot will really depend on if we can get a disturbance or two to move into eastern TX and then continues to slide under the building ridge to our north. If that occurs then there is a good chance of scattered convection Thursday. Friday may be a little more difficult as the ridge should continue to build to the south and will try to weaken the northwest flow. If the ridge is able to phase with the broad ridging in the Gulf and west Gulf coast then we probably get blocked with a drier and warmer fcst than what we are currently advertising for Thursday. Through the weekend things continue to remain uncertain. The pattern is progressive and is changing every 2 to 3 days which should start to slow down as we move deeper into the Summer. Timing the troughs and ridges along with the strength of each is the issue and down here along the Gulf coast, these features could be highly dictated on convection the day and night before. At this time if looks like we could move back under northwest flow Saturday with a decent shot of convection. That would also likely help keeps things on the slightly cooler side with highs still in the mid 80s to possibly lower 90s. However, that swings back to the other side with a ridge building over the southern Plains and quickly shifting east across the Lower MS Valley late Sunday. If it is a little slower then perhaps we have another decent shot of scattered convection. && .AVIATION... (06Z TAFS) Issued at 1146 PM CDT Mon May 27 2024 Latest guidance is still showing chances for some patchy fog in western areas, mainly impacting HUM. This may briefly bring MVFR or even IFR conditions after 09Z, clearing out after 14Z. A few models are hinting at more widespread thunderstorm activity tomorrow evening, mainly for western and southern areas, but not enough confidence to add TSRA or VCTS. Regardless this is something that will need to be monitored as further guidance comes in. Outside of storms if they do fire, VFR conditions expected. && s .MARINE... Issued at 340 PM CDT Mon May 27 2024 Surface high pressure currently centered just north of the Bahamas and extends westward across the entire Gulf of Mexico. A cold front, located near the LA/AR border, will approach the local area from the north which will weaken the pressure gradient between it and the surface ridge. Thus, should see a weakened wind field and seas/waves the remainder of this week. && .PRELIMINARY POINT TEMPS/POPS... MCB 69 93 68 85 / 20 20 10 30 BTR 77 96 73 89 / 20 20 10 30 ASD 75 96 72 90 / 20 20 10 20 MSY 79 94 76 89 / 20 20 10 30 GPT 75 94 73 89 / 20 10 10 20 PQL 73 96 69 91 / 20 10 10 20 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...MEFFER LONG TERM....CAB AVIATION...HL MARINE...MEFFER