787 FXUS62 KTBW 171202 AFDTBWArea Forecast Discussion National Weather Service Tampa Bay Ruskin FL 802 AM EDT Wed Sep 17 2025
...New AVIATION...
.DISCUSSION... Issued at 217 AM EDT Wed Sep 17 2025
An upper low and surface low pressure center remains over the mid- Atlantic states. These features will be slow to lift out remaining over that region through Thursday when it finally lifts out to the northeast over the western Atlantic. Closer to Florida, weak upper level ridging and surface high pressure northeast of the Bahamas and over the southeast U.S. ridges over Florida. This will keep a predominant east-northeast wind flow over the region for the next couple of days. The 17/00Z upper air sounding is already showing increasing moisture over the region with a PWAT of 1.66 inches. Model guidance is still showing some drier air with a PWAT around 1.5 inches over the Nature Coast, which may limit rain chances over that area today and Thursday. Moisture will be a little more abundant over central and southwest Florida with PWAT values around 1.6 - 2.0 inches, which will equate to slightly higher rain chances over those areas for today and Thursday.
By Friday morning, an inverted trough sits between the Bahamas and the east coast of Florida. This feature will become the dominant weather feature over the region through the weekend. Models are showing a notch of drier air over Florida for Friday on the west side of this trough with PWAT values dropping to around 1.2 - 1.6 inches. This will equate to slightly lower rain chances on Friday and Saturday, especially for Tampa Bay northward. By Sunday, the inverted trough shifts slightly westward bringing an increase in moisture with PWAT values reaching 1.6 - 2.0 inches. This will allow for scattered showers and isolated storms each afternoon across the Florida peninsula for Sunday and continuing each day through the middle of next week. The highest rain chances will likely be over the east coast of Florida and southwest Florida.
Near seasonal temperatures expected through the period, with mid to upper 80`s to low 90`s expected each afternoon. Overnight lows will remain in the 60`s and 70`s through the week, then in the low to mid 70`s over the weekend and into next week.
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.AVIATION... (12Z TAFS) Issued at 754 AM EDT Wed Sep 17 2025
An upper level trough will push through South Florida today. This will bring passing showers most of the day to FMY and RSW. For the other terminals the trough will increase moisture leading to a better chance of shower and storms this afternoon and evening. VFR conditions outside of showers and storms with winds generally staying below 10 knots.
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.MARINE... Issued at 217 AM EDT Wed Sep 17 2025
East-northeast winds around 10-15 knots and seas 2 feet or less will prevail over the eastern gulf waters through Saturday. A slight uptick in winds and seas expected late Saturday into Sunday with northeast winds around 15 knots and seas up to 3 feet possible. Scattered showers and isolated storms possible each day, with the highest chances from Tampa Bay southward.
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.FIRE WEATHER... Issued at 217 AM EDT Wed Sep 17 2025
No fire weather concerns expected through the week as relative humidity values remain above critical levels and winds remain below 15 mph. Scattered showers and isolated storms possible each day, with the highest chances south of the I-4 corridor.
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.PRELIMINARY POINT TEMPS/POPS... TPA 89 74 90 75 / 50 30 30 10 FMY 87 73 90 73 / 60 40 70 20 GIF 89 73 91 73 / 60 30 40 10 SRQ 87 72 90 73 / 50 30 40 20 BKV 89 68 91 68 / 40 20 30 10 SPG 86 74 88 75 / 50 30 30 10
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Sea Breeze Thunderstorm Regime For Wednesday: 6 Sea Breeze Thunderstorm Regime For Thursday: 1
For additional information on sea breeze regimes, go to: https://www.weather.gov/tbw/ThunderstormClimatology
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.TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None.
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DISCUSSION/AVIATION/MARINE/FIRE WEATHER...Shiveley DECISION SUPPORT...Pearce UPPER AIR/CLIMATE...Pearce
NWS TBW Office Area Forecast Discussion