Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
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446 FXUS64 KLIX 280831 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 331 AM CDT Tue May 28 2024 ...New SHORT TERM, LONG TERM, AVIATION, MARINE... .SHORT TERM... (Today through Wednesday) Issued at 323 AM CDT Tue May 28 2024 We will start out with an important feature in the form of a front. Can`t legitimately call this a cold front since temps are as warm behind it as ahead of it but by definition it would be because there is an air mass change across its boundary via dew pts. This front currently(2am) is located where the storms are ongoing this morning along the Miss coast. The front is just off the coast south of Pascagoula coming onshore just east of Gulfport to just north of Hammond then snakes its way into west central LA and on into TX south of Dallas. This boundary will help a very large complex of elevated storms develop later today near the Red River Valley. This complex should do two things, one is massively cold pool southward toward the sfc boundary causing all kings of severe wx over central TX todaya as it becomes sfc based. Smaller disturbances from this will be able to use the frontal boundary to ride eastward as well. This will act as a conduit for our area. The problem is stability even with this boundary over the area. Numbers show where stability quickly erodes as one moves west today so the marginal risk of severe looks well placed as west of I55 is where downburst numbers and the most severe wx producing numbers are highest relative to our area. This scenario will play out over the next few if not several days and it will be important to know where this or any other boundaries are located on a daily basis. Instability numbers rise for Wed and again they are indicating that if something can actually break the cap and produce lightning it will likely become severe. Again, with upper NW flow regimes, it is always a daily struggle to find the processes in the mesoscale environment that will cause trouble. So today is most visible vs. tomorrow. The current storms moving along the cold pool boundary to the west from coastal Miss and over the gulf will eventually modify and stall with the storms gradually weakening. There is not one CAM that is showing any of this activity, but the GFS did pick up on this convective burst developing along this frontal boundary but it did not hang on to it past midnight. Regarless, this is also the only model that is keeping this modified cold pool near the western part of the CWA later today. At least one disturbance should develop near the Toledo Bend area and move east along the frontal boundary later today as well. It is this activity that should collide with this modified cold pool late this afternoon to cause at least some storms over the western half of the area. The reason we can put a bit more confidence in this is the existance of the features that will allow it to occur and provide the travel path. Cloud cover and somewhat slightly lower dew pts as this front will be near the coast later today will help keep heat index numbers in check. But it will still be hot. One can easily tell in this forecast where we and our neighbors are placing the frontal boundary as the highest precip numbers will be located along and south of its axis, for us this mainly be the afternoon/evening hours. Areas to the north of these higher precip numbers will get somewhat lower heat index values while cloud cover along and ahead of it will keep others from those numbers as well. As a side note, BTR broke the record for the warmest low temp yesterday(Monday). Also, this record of 82F has not been reached(with respect to our records) for any day since January 1st until *JULY 5th*. Yes, July 5th is the first time a low of 82F was hit for the first time since Jan 1st of any year since records began in 1892. And the record value of 82F on July 5th was set in 2016. This record high(low) was not reached for more than another month away. The odds of this occurring this early is insane. && .LONG TERM... (Wednesday night through Monday) Issued at 323 AM CDT Tue May 28 2024 If it is difficult to tell what is going to occur tomorrow, it is almost impossible to give an extended fcast in this kind of environment. But we can see where the synoptic features should be located, which gives us a better handle on areas that could be most vulnerable to these MCS features. Looking at the extended through the next several days, it looks as if there will be endless MCS features develop daily and move east along either the sfc boundary or the 850 boundary which will both be in flux on a daily basis as these disturbances push and pull it each day. The sfc part of this boundary fades by late Wed and is somewhat located along the Miss River Valley by Thu and is out of the picture Fri. The only thing steering these disturbances later in the week will be ThetaE gradients or old outflow boundaries. && .AVIATION... (12Z TAFS) Issued at 323 AM CDT Tue May 28 2024 VFR will be found at all terminals through this taf period with the exception of one or two. The most at risk terminal for IFR will be BTR late today. The next would be HUM. There is a chance to get some TSRA for these two locations and if this occurs, IFR conditions could quickly develop for a short time. && .MARINE... Issued at 323 AM CDT Tue May 28 2024 There is a chance for temporarily getting a northerly brz over waters to the east of the Miss River. This would be short lived and would not be an issue as speeds should remain around 5kt. Southerly winds of 10-15kt will remain over waters to the west of the river and after today, all areas will be back in return flow at these levels for the remainder of the week. Any storms that are capable of developing or moving offshore will be able to produce erratic and much higher wind speeds. && .PRELIMINARY POINT TEMPS/POPS... MCB 92 68 87 66 / 10 10 30 20 BTR 96 73 90 72 / 20 20 30 10 ASD 95 72 91 71 / 10 10 20 10 MSY 94 76 90 76 / 10 10 20 10 GPT 94 73 90 72 / 0 10 10 10 PQL 96 70 92 69 / 0 10 10 10 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...TE LONG TERM....TE AVIATION...TE MARINE...TE