Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
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234 FXUS64 KLIX 041814 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 114 PM CDT Tue Jun 4 2024 ...New AVIATION... .SHORT TERM... (Today through Wednesday) Issued at 241 AM CDT Tue Jun 4 2024 The draw northward of these MCS pathways was accomplished, just not far enough. Even though the bulk of these features have moved north of the area they are still able to drag their "feet" through the northern sections of the area this morning. The 1000mb ThetaE boundary is oriented rougly from Houma to Natchez then takes a NW path toward Shreveport. Once the latest MCS moved across the N-S part of this, it started rapidly decaying. The 850mb gradient did not make it to the northern portion of LA/MS and this is due to the synoptic draw not being as strong as the models were indicating. This will simply cause the pathways for these complexes to not be as far north as thought. The next MCS is getting started over central OK this morning. This will move eastward and then down the same travel path as the one that just moved through this morning. But as usual, as they enter our area and move to where this ThetaE axis orients N-S, it will begin to decay. The 00z runs of all models had this feature coming through the area with a well developed line, but have since backed way off. As most will tell you, "the trend is your friend", and I always say, "until it`s not", but since we have had a lot of trouble trusting the output of any CAM so far, we will stick to the path that got us here and keep the trend as is, bringing the southern extention of the next MCS into the area by this afternoon and exiting during the evening hours. We will keep this within that same time frame from 1-3pm for entry and exiting 9-11pm tonight. Would it surprise me that these times are later...no, but then again, nothing would surprise me at this point. So what about Wed? It has been hard enough figuring out day 1 much less day 2. But, the next MCS in this infinite line looks to get started over north central to NE OK late tonight and move east at first. The cold front that has been talked about for a while is moving south through Montana and Wyoming this morning and will be partly responsible for helping develop this next MCS tonight. The MCS will move along the frontal boundary at first until it finds the ThetaE gradients that this front will have oriented N-S from central AR to near Lafayette. It looks like this MCS cold pools and produces new cells along this gradient which begin to develop a new MCS that moves south into the area. This is highly sceptical at this point, but this is the picture being painted. If this is the case, this MCS would be moving through here late Wed afternoon/evening. && .LONG TERM... (Wednesday night through Monday) Issued at 241 AM CDT Tue Jun 4 2024 The other issue here is the frontal boundary itself. Models are trying to bring two fronts near and through the area respectively. The first arrives behind the Wed night MCS feature on Thu and the next would be late Fri or early Sat. This looks more like the MCS is the feature that rushes the first weaker front southward while the second and probably the actual synoptic front moves through late Fri. This front is steep and will definitely provide a forcing to help get things going for Fri or early Sat. The front stalls near the coast Sat and orients itself from here NW to the source region of the MCS train which allows another one or two to move into the area through Sat and maybe early Sun. All global models want to open up the weserlies with another cold front dropping out of Canada for Monday morning of next week. The raw model solutions drop temps into the low to mid 80s for Monday, but then statistical calcs and climo take those numbers and raise them 3 to 6F. Regardless, these fronts look to come in such rapidl succession that modification will occur, but may not have enough time to fully heat up the dry cool air behind the final one Monday. This is a stretch for this time of year, but it has occurred before. && .AVIATION... (18Z TAFS) Issued at 1255 PM CDT Tue Jun 4 2024 Main question for aviation interests is convective development. While TSRA are still well back toward KSHV, there`s been quite a bit of SHRA development in advance of that in the past 30-60, so we may need additional amendments to add thunder in the next few hours. Cloud bases generally between FL025 and FL035, but direct impacts could produce MVFR ceilings and IFR visibilities. Most convection should dissipate by 01z Wednesday. Potential for MVFR to IFR ceilings prior to sunrise Wednesday. Based on the last few days, certainly won`t rule out an additional round of convection on Wednesday. && .MARINE... Issued at 241 AM CDT Tue Jun 4 2024 Southerly winds of 10-15kt will remain over all waters through much of this week. Winds could become more westerly by the end of the week but wind speeds should remain light outside any storms that develop. A cold front is expected to stall along the coast late Fri and could temporarily shift winds to a northerly direction, but these winds are expected to be light outside storms. && .PRELIMINARY POINT TEMPS/POPS... MCB 89 71 89 70 / 60 20 30 30 BTR 92 75 94 76 / 40 20 30 20 ASD 91 75 92 74 / 30 20 20 20 MSY 90 77 92 76 / 30 10 20 20 GPT 87 77 89 74 / 40 20 30 30 PQL 89 74 90 74 / 30 10 20 30 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...TE LONG TERM....TE AVIATION...RW MARINE...TE