Area Forecast Discussion
Issued by NWS Jacksonville, FL
Issued by NWS Jacksonville, FL
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435 FXUS62 KJAX 010738 AFDJAX Area Forecast Discussion National Weather Service Jacksonville FL 338 AM EDT Wed May 1 2024 ...New NEAR TERM, SHORT TERM, LONG TERM, MARINE... .NEAR TERM... Issued at 338 AM EDT Wed May 1 2024 Weak shortwave aloft shifts off the SE US coast today as ridging gradually rebuilds back over the region. Low level moisture and clearing skies will lead to patchy fog developing across inland areas early this morning. Fog will be locally dense at times mainly for inland NE FL around sunrise. Fog will dissipate by mid- morning. Temperatures will rise into the mid to upper 80s and to around 90 in north-central FL. Weak pressure gradient, lingering moisture, and diurnal heating will produce widely scattered showers and isolated storms developing along the Atlantic and Gulf sea breezes as they shift inland in the afternoon and evening hours. Overnight lows will be in the 60s. Another round of patchy to areas of fog is expected to develop tonight mainly during the predawn and early morning hours at inland locations. For the latest NE FL and SE GA Daily Key Messages please visit: https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf && .SHORT TERM... (Thursday through Friday night) Issued at 338 AM EDT Wed May 1 2024 Ridging aloft will build over our region in the wake of the departing shortwave trough that will progress offshore of the Carolinas on Wednesday evening. A weak surface pressure pattern will prevail locally, with low level flow shifting to easterly, which will advect a drier and more subsident air mass over our area. Just enough moisture may remain around for isolated convection to develop towards sunset where the Atlantic and Gulf coast sea breezes collide, generally for locations along the Interstate 75 corridor. The drier air mass and plenty of sunshine will allow highs to soar to the upper 80s to near 90 degrees, while highs top out in the lower 80s at coastal locations, where prevailing onshore winds will become breezy during the afternoon hours. Patchy to areas of locally dense fog will again be possible during the predawn and early morning hours on Friday at inland locations. Otherwise, fair skies and southeasterly low level flow will result in lows only falling to the mid 60s inland and the upper 60s to around 70 at coastal locations. A large trough digging over the Pacific Northwest, the Rockies, and the High Plains States will direct a shortwave trough northeastward from the Ozarks on Thursday afternoon, the Tennessee Valley on Thursday night, and then across the Ohio Valley and Great lakes region on Friday and Friday night. PVA at the base of this shortwave trough will cross the southeastern states on Friday, which will flatten ridging over our region by late in the day. A dry air mass is expected to linger throughout much of Friday across our area, but model guidance is not in agreement on how quickly convection associated with the approaching PVA will approach our region during the afternoon and evening hours. Model blends currently keep most of our area dry into the evening hours, although some isolated convection developing along mesoscale boundaries cannot be ruled out. Plenty of sunshine from Friday morning through the mid-afternoon hours and the lingering dry air mass will again boost highs to around 90 at most inland locations, with the afternoon Atlantic sea breeze keeping coastal highs in the lower 80s. Lows on Friday night will only fall to the 65-70 degree range at most locations as convective debris clouds from upstream convection filter overhead. && .LONG TERM... (Saturday through Tuesday) Issued at 338 AM EDT Wed May 1 2024 Flow aloft will become zonal over the southeastern states this weekend through Monday of next week as longwave trough progresses from the High Plains northeastward through the Upper Midwest and the Great Lakes states. A series of shortwave troughs embedded within the zonal flow pattern will progress across our area during this time frame, with deeper moisture pooling over the southeastern states ahead of a frontal boundary that will eventually stall out well to the northwest of our region. Scattered mostly diurnal convection can be expected each day across our area this weekend. Weak flow aloft should preclude any severe weather threat, with longer term models also suggesting that higher CAPE values will remain west of our region. Temperatures this weekend will remain slightly above early May climatology this weekend through Monday. Forecast confidence decreases on Monday as another shortwave trough embedded in the zonal flow pattern progresses across the Tennessee and Ohio Valleys, which could advect another PVA lobe across the Deep South that would spark mainly diurnal convection across our area. Model blends currently depict decreasing rainfall chances on Monday, and temperatures in this drier scenario would begin their climb back up to near 90 degrees at inland locations. Ridging aloft will then build towards the FL peninsula on Tuesday, as our area would be downstream of of another digging longwave trough over the Pacific Northwest, the Rockies, and the High Plains. This weather pattern will bring increasingly hot and drier weather to our area for much of the rest of next week, as Atlantic surface ridging extends its axis westward across the FL peninsula. West-southwesterly low level flow will strengthen, which will delay or hinder the development of the cooling afternoon Atlantic sea breeze, resulting in temperatures soaring to the lower 90s inland and the 85-90 degree range at coastal locations. Overnight lows through the long term period will only fall to the 65-70 degree range inland and the lower 70s at coastal locations. && .AVIATION... (06Z TAFS) Issued at 113 AM EDT Wed May 1 2024 Showers over SSI will shift offshore within the next couple of hours. Light and variable winds will continue through the mid- morning. Increased low level moisture will support better chances for fog/low stratus towards sunrise and have continued LIFR fog chances at VQQ, and MVFR fog chances at GNV/JAX in the 08-11Z time frame. Diurnal heating and sea breeze circulations pushing inland will support another round of isolated to widely scattered showers by the afternoon hours at all TAF sites, but TSRA chances remain too low below 20 percent for inclusion at this time. && .MARINE... Issued at 338 AM EDT Wed May 1 2024 Weakening frontal boundary will stall just North of the waters today. Winds will be light with afternoon surges of onshore winds with the Atlantic sea breeze shifting inland. High pressure center will then build over coastal New England late this week. A cold front is then expected to enter the southeast states by Saturday night and Sunday, bringing a chance of showers and thunderstorms to our region by late in the upcoming weekend. Rip Currents: High risk of rip currents continue today for NE FL beaches. Moderate risk on Thursday as seas subside. Moderate risk of rip currents continue for SE GA beaches through Thursday. && .PRELIMINARY POINT TEMPS/POPS... AMG 87 64 89 65 / 20 20 10 0 SSI 82 68 80 67 / 30 10 0 0 JAX 87 66 85 66 / 30 0 10 0 SGJ 84 68 82 68 / 20 10 10 0 GNV 88 65 89 65 / 30 30 20 0 OCF 90 65 90 65 / 30 30 20 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through late tonight for FLZ124-125-133- 138. GA...None. AM...None. && $$