Area Forecast Discussion
Issued by NWS
Issued by NWS
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155 FXUS62 KTAE 010526 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 126 AM EDT Sat Jun 1 2024 ...New AVIATION... .UPDATE... Issued at 933 PM EDT Fri May 31 2024 The main update to tonight`s forecast was fine-tuning rain chances based on current trends. Evening vapor imagery shows a well- defined shortwave trough moving towards the MS/TN Valley forcing an area of showers and thunderstorms just to the west of our service area. Remnant outflow boundaries from this preceding convection aims to be a focus for redevelopment of thunderstorm clusters (some of which could be strong to severe) into the western FL Panhandle and parts of SE AL by daybreak. The main threats are strong/gusty winds with isolated severe gusts possible. Locally heavy rain is an additional concern. Hi- resolution models and CAMs are in good agreement on the spatial/temporal coverage. Quiet weather should prevail mainly east of the Apalachicola River should where ridging influence is more prominent. && .NEAR TERM... (Through Saturday) Issued at 234 PM EDT Fri May 31 2024 Upper-level ridging, currently near the AL/GA border, will continue pushing across the local area through the period. This ridge will strengthen and become more amplified late tonight and into tomorrow as it approaches and moves into the western Atlantic. Subsidence from this ridge should keep PoPs low for the remainder of the day and into the evening hours, although a few isolated sea breeze showers/storms cannot be ruled out. Highs today will reach the upper 80s to low 90s, with a few locations over the Florida Panhandle reaching the mid 90s. As we head into tonight, a shortwave trough is expected to move into the Lower Mississippi River Valley, with several shortwave impulses riding along the base of the trough. The best large-scale forcing should remain to the west of the local area due to the presence of the nearby ridge, however, maintained 20-30% PoPs for locations over southeast Alabama and the western Florida Panhandle to account for the uncertainty of how far east the storms will develop during the overnight hours. The main wave of showers and storms is expected to move into the region Saturday morning and into the afternoon hours as the ridge continues its eastward progression and the shortwave trough moves into the Tennessee River Valley. Highest convective coverage should remain confined to the western half of the region, as the eastern half remains under the influence of the ridge. Ongoing storms over Alabama/Mississippi should begin to organize into multicellular clusters and eventually into an MCS as deep-layer shear begins to increase and punch into the developing storms. CAPE values should also generally increase to around 1500 to 2500 J/kg during the morning as well. Therefore, cannot rule out storms capable of producing severe winds in excess of 60 mph. Due to this risk, a marginal risk of severe storms is in place across the Central Time Zone counties. At this point, due to the developing LLJ remaining well to the north (and therefore weak low level shear in place), no tornadoes are expected. Additionally, storms will also be capable of producing high rainfall rates which could lead to some localized or nuisance type flooding especially given the high PWATs and slower storm motions. Lows tonight will range from the upper 60s to low 70s. Highs tomorrow will range from the low to mid 80s over the west due to the widespread rainfall and cloud cover, and the mid to upper 80s, to around 90 for the eastern half of the region. /96 && .SHORT TERM... (Saturday night through Monday night) Issued at 234 PM EDT Fri May 31 2024 An upper trof which extends from near the Great Lakes to the north central Gulf coast gradually weakens while continuing into the western Atlantic during the period, with a series of shortwaves meanwhile progressing across the area. A surface ridge over the southeastern states weakens through Monday night but nevertheless maintains a moist southerly flow over the forecast area, with precipitable water values of 1.5-1.75 inches slowly increasing to 1.75-2.0 inches. For Saturday night, have gone with dry conditions over the eastern portion of the area with slight chance to chance pops over the western portion. Chance to likely pops follow for Sunday as deep layer moisture gradually improves along with a continuing series of shortwaves moving across the area. Mostly slight chance pops follow for Monday as the series of shortwaves look to weaken. May see a few strong storms develop early Saturday evening. Lows Saturday night through Monday night typically range from the upper 60s to lower 70s. Highs on Sunday will be in the mid to upper 80s and highs on Monday will be in the upper 80s to lower 90s. A high risk of rip currents is expected for Saturday night through Monday. /29 && .LONG TERM... (Tuesday through Friday) Issued at 234 PM EDT Fri May 31 2024 An upper trof over the northern and central Plains steadily amplifies while spreading into the eastern states, and an associated surface low passes well to the north and brings a weak cold front through the forecast area Thursday night, although there is the potential for the front to stall near the coast. Plenty of deep layer moisture remains in place over the forecast area through Thursday, then drier air works into the area on Friday with precipitable water values looking to drop to 1.2-1.7 inches, with the lower values over interior areas. Forcing looks to be limited over the area Tuesday and Wednesday so have gone with mostly slight chance pops. Slight chance to chance pops follow for most of the area on Thursday and Friday as the front approaches and moves into, possibly through the area. /29 && .AVIATION... (06Z TAFS) Issued at 121 AM EDT Sat Jun 1 2024 SHRA/TSRA is expected to increase in coverage across southern Alabama in the overnight hours then approach DHN/ECP in the morning hours from 14-20Z. Strong winds and heavy rainfall resulting in tempo MVFR/IFR conditions will be possible during this time frame. Further east, it may make it into TLH in the late afternoon hours but will be on a weakening trend by the time it arrives. Added a PROB30 to account for this at TLH. At ABY/VLD, convection will either be located south of ABY through the day or dissipate west of VLD to keep conditions VFR and no mention of convection. && .MARINE... Issued at 933 PM EDT Fri May 31 2024 Offshore buoys were reporting light east to SE winds with 2-3 ft seas and a dominant period of 5 sec this evening. Forecast marine winds were increased overnight by using a blend of the CAMS/HRRR, which show solid 20 to 22+ kts of surging easterly winds starting at Apalachee Bay around 3Z, then spreading west towards the remaining waters as we approach dawn. A Small Craft Advisory remains in effect until 15Z. From CWF Synopsis...Winds become predominately southeasterly and strengthen overnight to advisory levels via an easterly nocturnal surge then diminish on Saturday. A light to moderate southeasterly to southerly flow prevails for Sunday through Tuesday, then a southwesterly flow develops on Wednesday. Showers and thunderstorms are likely at times late tonight through Saturday, mainly over the northeast Gulf waters. && .FIRE WEATHER... Issued at 234 PM EDT Fri May 31 2024 Isolated to numerous showers and storms are expected on Saturday, with the higher coverage generally over south central Alabama and portions of the western Florida panhandle. Afternoon relative humidity values remain above critical levels. Transport winds will be mostly southeasterly Saturday and southerly on Sunday. Dispersion index values will be generally good to good on Saturday and fair to generally good Sunday. /29 && .HYDROLOGY... && .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 70 89 69 91 / 10 40 10 20 Panama City 72 86 72 87 / 30 50 10 20 Dothan 67 87 69 89 / 20 50 10 20 Albany 68 87 68 89 / 10 40 10 20 Valdosta 67 89 68 91 / 10 30 10 20 Cross City 67 91 68 92 / 10 20 10 20 Apalachicola 74 84 73 86 / 20 40 10 10 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 5 AM EDT /4 AM CDT/ early this morning for FLZ108-112-114-115. GA...None. AL...None. GM...Small Craft Advisory until 11 AM EDT /10 AM CDT/ this morning for GMZ730-750-752-755-765-770-772-775. && $$ NEAR TERM...DiCarlo SHORT TERM...Eversole LONG TERM....Eversole AVIATION...Scholl MARINE...DiCarlo FIRE WEATHER...Eversole HYDROLOGY...Eversole