Area Forecast Discussion
Issued by NWS
Issued by NWS
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403 FXUS62 KTAE 301737 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 137 PM EDT Sun Jun 30 2024 ...New AVIATION... .UPDATE... Issued at 1036 AM EDT Sun Jun 30 2024 Slightly lowered PoP`s for portions of out SE AL and SW GA counties as the higher probabilities for more widespread precipitation today lie within our FL counties, particularly in the Big Bend. Some weak isolated showers are currently forming across our CWA as better instability continues to build over the region. Mesoanalysis shows PWAT`s ranging from 2-2.4" and weak flow aloft, supportive of the previous forecast indicating that another round of nuisance / localized flash flooding may be possible this afternoon. Temperatures are also on track to flirt with heat advisory criteria (heat indices ranging from 108-112). A few observation sites across our FL counties have already broken into the low 100s. Heat advisory criteria may be met, though it is expected to be brief and perhaps less than an hour given storms keeping temperatures cooler. && .NEAR TERM... (Today and tonight) Issued at 256 AM EDT Sun Jun 30 2024 Upper level high pressure continues to saunter its way in from the west, while a moist airmass remains in place. This will lead to yet another day of scattered to widespread popcorn thunderstorms. PWATs remain on track to vary from 2.2-2.5" and the wind shear and steering flow isn`t too impressive. This could lead to another day of heavy rainfall with localized nuisance or flash flooding being possible. Outside of the storms, we`ll have another hot and muggy day in store. Opted to blend temperatures a few degrees down based on MOS guidance, with highs peaking in the low to mid 90s. Heat Index Values will slowly climb through the day and range from 100-111 degrees. Opted to not issue a Heat Advisory given the small time frame it is expected to occur, which overlaps with ongoing convection. The uncertainty remains high on whether or not temperatures will be realized because of this due to rain cooled air and anvil debris. One can always practice heat safety in the summer by wearing light clothes, drinking plenty of water, and limiting time outside if possible. && .SHORT TERM... (Monday through Tuesday night) Issued at 256 AM EDT Sun Jun 30 2024 Mid and upper level ridging centered over the ArkLaTex region will lead to an anticyclonic wave breaking episode across the eastern conus Monday. This will lead to a digging trough through the Mid- Atlantic states on Monday. This will lead to a subsequent frontal boundary pushing southeast through the deep south during the day on Monday. With deep tropical moisture remaining in place across the region Monday, widespread showers and thunderstorms are expected, with the highest chances remaining across the Florida Panhandle and Big Bend where seabreeze interactions will likely take place. The frontal boundary looks to usher enough dry air through the mid levels that DCAPE values will be in the 800-1000 J/Kg range. This has prompted a marginal risk (level 1 of 5) for much of the area both Monday and Tuesday from SPC. The greatest impacts from these storms will be strong to severe winds of 60 mph or greater. Overall, high temperatures will reach the low to mid 90s on Monday and Tuesday, and lows will generally remain in the mid 70s. && .LONG TERM... (Wednesday through Saturday) Issued at 256 AM EDT Sun Jun 30 2024 Upper level ridging is expected to slide east once again from the ArkLaTex region towards the deep south by Wednesday in the wake of the frontal passage on Monday and Tuesday. The upper level ridging pattern will lead to subsidence areawide, which will limit the overall rain chances across the region; however, it looks like the dry air that was forecast to push into the region from the northeast by Thursday will remain just east of the region. This will likely keep 2-2.25 inch PWATs in place over the region, and inevitably lead to widespread showers and thunderstorm development through the end of the period. High temperatures look to creep back up into the upper 90s by the end of the work week as the aforementioned upper level ridge settles over the deep south. Lows will generally remain fairly steady in the mid to upper 70s. && .AVIATION... (18Z TAFS) Issued at 134 PM EDT Sun Jun 30 2024 VFR to MVFR conditions are generally expected to prevail through the TAF period with a light to moderate northwest to northerly wind. That said, several showers and thunderstorms are forecast to roam the region this afternoon into the early evening hours. Brief IFR conditions due to visibility and/or ceilings are possible within any of the storms. Fog cannot be entirely ruled out for areas that pick up a good bit of rain later today/tonight. So illustrated that with some lowering of the visibilities at KTLH; these trends will be monitored and adjusted in future TAFs. && .MARINE... Issued at 256 AM EDT Sun Jun 30 2024 Wave periods notably increased through the overnight hours via southerly swells with an uptick in seas between 3-4 feet. Southwesterly flow around 10 knots and seas around 3 to 4 feet will prevail through the remainder of the weekend until a weak frontal boundary pushes into the Gulf late Monday and winds become light and variable in its wake. Wave heights of 3-4 feet will predominantly be attributed to the tropical disturbance in the southern Gulf of Mexico that is currently entering the Bay of Campeche. Scattered showers and storms are expected through the weekend and early next week with activity generally greatest in the overnight and early morning hours as the diurnal land breeze circulation is at its peak. && .FIRE WEATHER... Issued at 256 AM EDT Sun Jun 30 2024 Another day of afternoon showers and thunderstorms are forecast, with gusty and erratic winds, heavy down pours, and frequent lightning all being possible. Prior to that though, temperatures will rise into the low to mid 90s. Given the moist airmass in place, heat index values will sore to about 100 to 110 degrees for perhaps a few hours; however, this could thwarted if storms develop early enough. A similar story for high temperatures and heat index values looks like on Monday as well. No fire weather concerns are forecast as dispersions are expected to be fair to generally good area wide. && .HYDROLOGY... Issued at 256 AM EDT Sun Jun 30 2024 Widespread forecast rainfall totals of 2-3 inches are expected over the next 5 days, with much of this rainfall expected on Sunday and Monday. This is primarily due to deep tropical moisture remaining in place over the region through the middle of next week. PWATs will generally remain around 2-2.25 inches, which will lead to extremely efficient warm rain processes in developing convective structures during the afternoon and evenings the next several days. Recent HREF and ECAM guidance has very high probabilities of 5 inches of rain or greater for portions of the Florida Big Bend and SW Georgia for Sunday. While these are high values, they will likely remain very localized, and a similar scenario could develop that occurred on Saturday across the region, where extremely slow moving thunderstorms produce 3-6 inches of rain in a 1-2 hour window. This will likely lead to localized flash flooding, especially in poor drainage and urban environments due to the aforementioned extremely efficient rain processes and high rainfall rates expected. Given the convective nature of the rainfall, it will be too difficult to pinpoint exact locations that will receive these higher end rainfall totals to be able to issue a flash flood watch at this time. Overall, these higher totals in the 3-6 inch range are expected to remain localized in nature. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 92 76 92 76 / 60 70 70 30 Panama City 91 78 92 77 / 60 50 70 30 Dothan 92 76 95 75 / 50 50 50 30 Albany 94 76 95 74 / 60 50 60 40 Valdosta 94 76 93 75 / 60 50 70 50 Cross City 93 75 92 75 / 70 50 70 30 Apalachicola 90 79 88 79 / 70 60 70 30 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through late Tuesday night for FLZ108-112- 114-115. GA...None. AL...None. GM...None. && $$ NEAR TERM...KR SHORT TERM...Bunker LONG TERM....Bunker AVIATION...Reese MARINE...Bunker FIRE WEATHER...KR HYDROLOGY...Bunker