Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
210 FXUS64 KLIX 141116 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 616 AM CDT Fri Jun 14 2024 ...New AVIATION... .SHORT TERM... (Today through Sunday Night) Issued at 343 AM CDT Fri Jun 14 2024 Convective activity will remain suppressed today and tomorrow as deep layer ridging becomes centered over the region. Very dry air aloft associated with deep layer subsidence will effectively cap off any rain chances over most of the forecast area, and PWATS will fall to around an inch over northern zones and closer to 1.4 inches along the coast. These values are in the 10th to 25th percentile for mid-June. Temperatures will also be warmer than average with readings in the mid to upper 90s expected. Fortunately, the drier air mixing down to to the surface will keep dewpoints just low enough to produce heat index values of 100 to 105. These values are below our advisory criteria, but those who are more susceptible to heat illness including children and the elderly should limit time outdoors on Friday and Saturday. Additionally, the lack of wind and the strong inversion will lead to lower air quality today, and an air quality alert is in effect for metro Baton Rouge, metro New Orleans, and the MS Gulf Coast. The deep layer ridge axis will shift to the east of the area on Sunday, and this will open the door for a plume of deeper tropical moisture to begin feeding into the region. Sunday will see PWATS rise back to average for mid-June, and this will allow for greater convective activity from Sunday afternoon through Sunday night. PoP values will range from 30 to 50 percent north of I-10 and 50 to 70 percent south of I-10. The highest rain chances will be along the immediate coast and offshore where the deepest moisture is expected. The influence of the departing ridge will still be felt, especially over northern zones, as drier air in the mid- levels lingers. Downdraft CAPE values of 1000 to 1200 J/KG are expected over the northern half of the CWA Sunday afternoon, and there is the potential for a few wet microburst events to occur. The strongest convective updrafts punching above 20k feet will have the greatest potential for microburst development as dry air entrainment into the updraft occurs. There will be some locally higher rainfall rates Sunday into Sunday night, and this could lead to some street flooding issues in poorly drained and low lying areas. Temperatures will be closer to seasonal averages on Sunday into Sunday night due to the increase in convective coverage. && .LONG TERM... (Monday through Thursday) Issued at 343 AM CDT Fri Jun 14 2024 There has been little change in thinking from Monday through Wednesday from previous forecasts. The region will remain on the western periphery of a deep layer ridge and deep tropical moisture will continue to feed into the region. PWATS will be in the 90th percentile or higher each day with readings of between 2 and 2.25 inches expected. The result will be numerous showers and thunderstorms forming each day as temperatures climb into the mid to upper 80s. This is reflected by the high PoP values of 60 to 80 percent forecast each day. The convective activity will decrease in coverage a bit each night as temperatures cool back into the 70s, but will still be at least scattered in nature. Storm motion will remain decent at 10 to 15 knots on Monday and Tuesday with a further increase to around 20 knots on Wednesday. However, very high rainfall rates of 3 to 4 inches per hour with the strongest convection could lead to some localized flash flooding issues each day next week. The highest threat will be for urban drainage systems that could be easily overwhelmed by these excessive rainfall rates. Thursday will see a change in the pattern as the deep plume of tropical moisture shifts toward Texas and an inverted trough axis associated with a more easterly flow regime aloft begins to move into the Gulf South. PWATS will decline back to more average levels for mid-June, and this will result in convective coverage becoming more scattered in nature. The decrease in convection and cloud cover will also allow temperatures to climb back to more normal levels in the lower 90s. && .AVIATION... (12Z TAFS) Issued at 615 AM CDT Fri Jun 14 2024 VFR conditions and light winds are expected at all of the terminals. Wind direction at NEW, GPT, MSY, and HUM will feel in the influence of the sea-breeze and lake-breeze cycle with winds shifting to the south after 15z and increasing in speed at HUM and GPT and winds shift to the north and increasing in speed at MSY and NEW. These winds will persist through 02z before turning more variable as temperatures begin cooling after sunset. && .AVIATION... (06Z TAFS) Issued at 343 AM CDT Fri Jun 14 2024 A dry and stable high pressure system centered over the area will keep VFR conditions and light winds in place at all of the terminals. Wind direction at NEW, GPT, MSY, and HUM will feel in the influence of the sea-breeze and lake-breeze cycle with winds shifting to the south after 15z and increasing in speed at HUM and GPT and winds shift to the north and increasing in speed at MSY and NEW. These winds will persist through 02z before turning more variable as temperatures begin cooling after sunset. && .MARINE... Issued at 343 AM CDT Fri Jun 14 2024 Benign conditions will remain in place across all of the waters through tomorrow as high pressure remains centered directly over the region. On Sunday, the high will shift to the east and a developing area of low pressure in the Bay of Campeche will lead to a tighter pressure gradient across the northern Gulf. East and southeast winds will be on the increase through the first half of next week with prevailing small craft advisory conditions expected over the open Gulf waters by Monday afternoon. A decent swell train is expected form as these long fetch winds of 20 to 25 knots extend from the eastern Gulf into the northern Gulf. This swell will combine with the wind waves already in place to produce seas of 7 to 10 feet in the open Gulf waters. Additionally, the prolonged nature of these stronger onshore winds will lead to some minor coastal flooding issues by Tuesday. && .PRELIMINARY POINT TEMPS/POPS... MCB 95 71 98 73 / 10 10 10 10 BTR 95 74 97 75 / 10 10 10 10 ASD 96 74 96 75 / 10 10 10 10 MSY 93 78 95 79 / 10 10 10 10 GPT 93 77 95 79 / 10 10 10 10 PQL 94 74 95 76 / 10 10 10 20 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...PG LONG TERM....PG AVIATION...PG MARINE...PG