Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
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570 FXUS64 KLIX 182030 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 330 PM CDT Sat May 18 2024 ...NEW SHORT TERM, LONG TERM, MARINE... .SHORT TERM... (This evening through Sunday night) Issued at 330 PM CDT Sat May 18 2024 As an H5 shortwave continues downstream over the Panhandle of Florida this afternoon, the surface cold front will very slowly continue to move southward. Convection is still firing and back- building along this front, which is mostly driven by the cold pool at this juncture with mean level flow becoming more in line with the orientation of the frontal system. Surface high pressure will build into the region this evening and overnight, which should allow for more light and variable winds to take shape. With skies clearing over much of the CWFA and fairly moist soils from recent heavy rainfall, some radiational fog will be possible. SREF probs aren`t too extreme with less than 1 miles visibilities, however, there is a strong enough signal for patchy fog after midnight and lingering an hour or so after sunrise on Sunday. That said, the fog favored spots, especially the cooler low spots during radiational cooling events may see a more dense fog situation develop. Again, guidance isn`t very bullish with this solution as of yet, so no fog headlines, but something the evening and overnight crew will need to monitor. The story through Sunday and Sunday Night will again be the overall pattern change from active to a drier pattern. Northwesterly flow develops as a 594dam H5 heat bubble builds over central Mexico. Ridging from this mid level high noses up the Texas Gulf Coast and begins to overspread our region in wake of the departing shortwave now exiting the area. With this occurring, Sunday looks to be several degrees warmer, especially with the added insolation with many of us climbing to or above 90F. && .LONG TERM... (Monday through Friday night) Issued at 330 PM CDT Sat May 18 2024 The long term begins no different than much of the short term. The upper level regime is a dry north or northwesterly flow, again around the eastern periphery of the H5 heat bubble spreading eastward across Mexico. The upper level ridging becomes a bit more pronounced over the region going into Monday and Tuesday. With the increasing heights and thicknesses, temperatures will respond by continuing the warming trend. Early in the week the warming trend will be a bit more tolerable. With the strong insolation some mixing of dry air just off the deck will help keep heat index values rather reasonable. This is of course with surface high pressure around and little to no low level moisture advection. That said, by Wednesday the high begins to move east and brings back a more pronounced southerly return flow. Although good news for coastal areas...this return flow and relatively low SSTs over the shelf waters will help keep those areas slightly cooler. The influx of moisture will cause inland areas to experience climbing heat index values with moderation occuring. In fact, as the upper level high continues to build east over the western Gulf of Mexico, temperatures again continue to respond by gradually increasing. Inland locations Thursday, Friday and perhaps beyond will likely at least touch 100F "feels like" temps briefly during the afternoon hours. We will also be watching another front and parent shortwave move generally toward the Midsouth region. The GFS and ECMWF have aligned a bit better compared to yesterday with the GFS less bullish in terms of bringing the front through our CWFA late week or early next weekend. This will cause a more limited POP/QPF signal as much of the better dynamics will reside north of our region across northern Louisiana to northern Alabama. Cannot rule out a shower or two in our interior southwest MS Counties, but the current solution at this juncture is very limited in any rainfall from Thursday through Friday. If the shortwave is a bit more amplified, then the front could be a bit closer and rain chances respectively increase, so some adjustment is still possible through the medium range. (Frye) && .AVIATION... (18Z TAFS) Issued at 1221 PM CDT Sat May 18 2024 Mostly VFR with a few isolated pockets of MVFR CIGS to start this cycle. VFR should win out later this afternoon and evening. VIS reductions will be possible for most terminals with the lowest VIS for the fog favored locations such as MCB and HUM. This should lift quickly after sunrise Sunday morning leading to VFR conditions to end the cycle. Winds will continue to remain mostly light and variable. (Frye) && .MARINE... Issued at 330 PM CDT Sat May 18 2024 Convection along the southward moving cold front will continue through the afternoon. In and around these storms locally strong gusty winds, hail, and enhanced wave heights will be possible. This activity should move south and east out of our waters later this evening and into the overnight. By Sunday a surface high pressure should build into the region. This will bring down both winds and seas. Beyond this weekend and going well into the start of the new workweek, favorable marine conditions are generally in the cards as a light to moderate southerly flow develop by mid to late week. (Frye) && .PRELIMINARY POINT TEMPS/POPS... MCB 65 87 65 90 / 10 0 0 0 BTR 70 91 71 93 / 0 0 0 0 ASD 69 91 69 91 / 0 0 0 0 MSY 72 89 74 90 / 0 0 0 0 GPT 69 89 70 89 / 10 0 0 0 PQL 67 91 66 90 / 10 0 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...RDF LONG TERM....RDF AVIATION...RDF MARINE...RDF