Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
Issued by NWS Tampa Bay Area, FL
763 FXUS62 KTBW 160749 AFDTBW Area Forecast Discussion National Weather Service Tampa Bay Ruskin FL 249 AM EST Thu Jan 16 2025 ...New DISCUSSION, AVIATION, MARINE, FIRE WEATHER... .DISCUSSION... Issued at 150 AM EST Thu Jan 16 2025 Split flow U/L pattern persists across the CONUS with southern stream flow across the southern tier of the U.S., and the northern stream flow extending from western Canada to the mid Atlantic coast...with a series of U/L disturbances embedded in the northern stream. Lead S/W will move across the mid Atlantic and Florida early today and then exit rapidly over the western Atlantic. This has created the increased mid/high cloudiness over the forecast area. Although radar has indicated a few very light showers, mainly over southwest Florida, atmosphere in the low levels is very dry and any rain aloft is evaporating before hitting the ground...although can`t rule out a light sprinkle through the morning hours. Transition day for the U/L pattern on Friday as a southern stream disturbance will eject east from the desert southwest and will be absorbed by the northern stream over the southern plains. The two streams will come in-phase creating a high amplitude pattern across the entire CONUS, carving out a deep extensive L/W trough from Hudson Bay through the plains states. Trailing will be a sharp U/L ridge off the west coast of the U.S. extending to eastern Alaska. This will create a conveyor belt for arctic air to plunge south out of Canada across the central U.S. Along the leading edge of the cold air, an area of low pressure will develop and move across the Lower Mississippi Valley Friday night. Return flow will develop over the Florida peninsula advecting warmer much moister air across the forecast area. On Saturday, the area of low pressure will move across the southeast U.S. with an associated cold front approaching north Florida. A band of showers and isolated thunderstorms ahead of the front will push slowly southeast over the nature coast Saturday afternoon, and west central Florida Saturday night and early Sunday. The front will become increasingly parallel to the U/L flow and will be very slow to move across the region not clearing southwest Florida until late Sunday. Canadian high pressure will build over the forecast area in the wake of the front early next week with much colder drier air advecting across the region. Significant uncertainty in whether this will be a glancing blow of cold air with the U/L southern stream flow protecting the region...or a more significant cold weather event with below freezing temps possible for portions of the area Tuesday and Wednesday nights. Will continue to monitor how this evolves over the next several days. && .AVIATION... (06Z TAFS) Issued at 150 AM EST Thu Jan 16 2025 VFR conditions will prevail for the next 24 hours with skies BKN120 and BKN-OVC250. Areas of SCT LCL BKN 050-060 will develop by this afternoon mainly south of SRQ. && .MARINE... Issued at 150 AM EST Thu Jan 16 2025 High pressure will hold over the waters through Friday with winds and seas gradually subsiding. A cold front will approach the area late Saturday with increasing south to southwest winds ahead of the front. The cold front will push across the waters Saturday night and Sunday with gusty north to northwest winds developing in the wake of the front with SCA conditions possible, which could persist through mid week. && .FIRE WEATHER... Issued at 150 AM EST Thu Jan 16 2025 Relative humidity values will remain above critical levels today. Warmer temperatures on Friday will allow minimum afternoon relative humidity values to drop into the mid 30s across the nature coast and portions of the interior. However, winds are expected to remain less than 15 MPH. && .PRELIMINARY POINT TEMPS/POPS... TPA 64 48 69 56 / 10 0 0 10 FMY 68 53 71 59 / 20 20 10 10 GIF 64 46 70 56 / 10 0 0 10 SRQ 67 50 71 58 / 10 0 0 10 BKV 64 40 70 49 / 10 0 0 10 SPG 62 52 67 58 / 10 0 0 10 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ DISCUSSION/AVIATION/MARINE/FIRE WEATHER...Oglesby DECISION SUPPORT...Oglesby UPPER AIR/CLIMATE...Oglesby