Area Forecast Discussion
Issued by NWS
Issued by NWS
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850 FXUS62 KTAE 181709 AFDTAE Area Forecast Discussion National Weather Service Tallahassee FL 109 PM EDT Tue Jun 18 2024 ...New AVIATION... .UPDATE... Issued at 1050 AM EDT Tue Jun 18 2024 Main changes to the forecast were to bump the winds up slightly with gusts of 15 to 25 kt occurring this morning, slightly higher along the Franklin County coast. Otherwise, no other changes were made to the forecast && .NEAR TERM... (Today and Wednesday) Issued at 431 AM EDT Tue Jun 18 2024 In the big picture, a very strong 500 mb ridge axis will expand and strengthen further from the southern Appalachians to the coast of New England over the next 24 hours. This has the benefit of steering the developing tropical cyclone in the southwest Gulf toward the western Gulf Coast, and away from us. A tight pressure gradient between these two prominent features will support unseasonably strong easterly breezes. Dry air from the strong mid-level high has spread across our region, with satellite-derived PW imagery showing values over land of 0.9-1.3 inches, with richer moisture to the south over the Gulf. These values are insufficient for deep, moist convection, but weak and low-topped showers are possible in the fast easterly flow, such as is being observed from JAX westward. Interestingly, satellite imagery shows a classic "screaming eagle" tropical wave passing north of the Bahamas early this morning. (It is called that because of its shape in satellite imagery.) This feature will pass across north- central Florida and the northeast Gulf late tonight and Wednesday. It will bring somewhat richer moisture from the Lower Suwannee Valley, across Apalachee Bay to the Forgotten Coast. It could increase the chance of showers and perhaps an isolated thunderstorms in these areas. For mariners, this feature will likely bring the strongest easterly breezes of the week late tonight and Wednesday morning. Frequent gale-force gusts are possible over the waters, and we could eventually need a Wind Advisory for the southeast-exposed coast of Franklin County. && .SHORT TERM... (Wednesday night through Friday) Issued at 431 AM EDT Tue Jun 18 2024 Strong easterly flow will continue. Within that flow regime, another easterly wave will pass our longitude on Friday. In advance of this feature, another pocket of deeper moisture will quickly traverse the region on Thursday, supporting isolated to scattered showers, perhaps an isolated thunderstorm over our FL counties. The arrival of the main wave on Friday should finally disrupt the straight-shot easterly breezes, and a more solid and sustained increase in moisture will arrive in the southeast flow behind the wave axis. && .LONG TERM... (Friday night through Monday) Issued at 431 AM EDT Tue Jun 18 2024 The strong 500 mb high to our northeast this week will settle south and weaken late this week, elongating into a large-scale subtropical ridge axis that will extend from the Southwest U.S. to well east of Bermuda. Guidance points to a broad weakness in the ridge over the Southeast States and Florida by early next week. Meanwhile, a surface ridge axis will settle southward across our region on Saturday night and Sunday, continuing south down the FL Peninsula on Monday. In response, our low-mid level flow will gradually clock around from southeast to southwest, though it will be fairly weak given proximity of the ridge axis. Even so, this direction will pump up a more richly moist maritime tropical air mass. Given increasing moisture and that weakness in the subtropical ridge axis, rain chances will continue to increase a bit each day. This could be the start of a wet period, with the CPC 6-10 day outlook showing odds leaning toward above normal rainfall. && .AVIATION... (18Z TAFS) Issued at 107 PM EDT Tue Jun 18 2024 VFR conditions will prevail with teh only aviation hazards being gusty easterly flow in the afternoons. Sustained winds will be around 10 to 15 knots through the TAF period but expect gusts from 20 to 25 knots in the daylight hours of the TAF period. && .MARINE... Issued at 1050 AM EDT Tue Jun 18 2024 Bumped winds up slightly this morning for the waters given Buoy 42036 was still reporting 20-22 kt winds and 7-8 foot seas. Winds for tonight were also adjusted upward slightly with near gale force gusts. Will evaluate later this shift for any needs for gale warnings overnight. From CWF Synopsis...Strong easterly breezes and rough seas will continue over the northeast Gulf through Friday morning, thanks to a tight pressure gradient between strong high pressure off the New England coast and a developing tropical cyclone over the Southwest Gulf. Winds will start to decrease on Friday, as the high pressure center to our northeast moves closer to Bermuda and extends a ridge axis across the Southeast States. && .FIRE WEATHER... Issued at 431 AM EDT Tue Jun 18 2024 The main story through at least Thursday will be unseasonably strong easterly transport winds and gusty daytime surface winds. When combined with a deeply mixed June atmosphere, high dispersion will prevail for the rest of this work week. Little, if any, rain is expected through Wednesday, then rain chances will climb a little each day from Thursday through the weekend. Winds will start to ease on Friday, with a return to light winds this weekend. && .HYDROLOGY... Issued at 431 AM EDT Tue Jun 18 2024 Significant or widespread flooding is not expected through this weekend. Little, if any, rain is expected through Thursday. Rain chances will increase some starting Friday, but rainfall should not be hydrologically significant. By Monday and Tuesday of next week, ensemble mean solutions show 1000-700 mb flow becoming southerly, pumping up a more richly moist maritime tropical air mass. With more moisture to work with, rainfall loading beneath storms will increase, as steering flow weakens and storm motions slow down. Therefore, there is increasing potential for isolated flash flooding starting early next week. && .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 73 93 74 93 / 0 10 10 30 Panama City 76 93 75 93 / 20 30 10 40 Dothan 72 90 72 91 / 0 0 0 10 Albany 71 90 70 92 / 0 0 0 10 Valdosta 71 91 72 93 / 10 20 10 20 Cross City 73 94 73 94 / 0 40 10 40 Apalachicola 79 90 77 90 / 50 40 30 40 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through late Thursday night for FLZ108-112- 114-115. GA...None. AL...None. GM...Small Craft Advisory until 1 PM EDT /noon CDT/ Thursday for GMZ730-750-752-755-765-770-772-775. && $$ NEAR TERM...Haner SHORT TERM...Haner LONG TERM....Haner AVIATION...Dobbs MARINE...Haner FIRE WEATHER...Haner HYDROLOGY...Haner