Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
326 FXUS62 KKEY 080816 AFDKEY Area Forecast Discussion National Weather Service Key West FL 416 AM EDT Tue Sep 8 2026 ...New DISCUSSION, MARINE, AVIATION... .KEY MESSAGES... - Moisture will linger across the region through midweek, supporting rain and thunderstorm chances. - The primary threat for any stronger thunderstorms will be dangerous lightning strikes. When thunder roars, go indoors. If on a boat, stay low, or go below. - Heat index values will range from 100-108 degrees daily, with little relief in the muggy conditions overnight. Know the signs of heat stress, take frequent breaks, and stay hydrated. && .DISCUSSION... Issued at 400 AM EDT Tue Sep 8 2026 Weak lower level troughing remains across the Florida peninsula this morning. This has contributed to the atmosphere remaining very moist. Last evenings sounding had a precipitable water of 2.25 inches which was above the 90th percentile for the date. There was a sliver of lower level inhibition, but CAPE was more than ample and lower level moisture was quite high. Surface winds and steering flow remain quite weak and often variable. Over the next few days, the troughing across Florida will wash out as a pressure ridge builds east southeastward off the Atlantic Coast and down along the Gulf coast. As this takes place, variable surface breezes will gradually firm up out of the east. Moisture and instability will remain high, while inhibition limited. This along with the increasing flow should keep shower and thunderstorm chances near to slightly above normal. Seasonable temperatures will continue with highs near 90 and lows in the lower to mid 80s. The surface ridge will retreat into the Atlantic late in the week and this evening as it shifts down the Florida peninsula. This will tip breezes a bit more southeasterly whilst continuing the usual peaks and lulls. Some drier air may arrive Friday, but will be followed by increased moisture during the weekend. && .MARINE... Issued at 400 AM EDT Tue Sep 8 2026 A loose pressure field across the area is resulting in light and often variable breezes on Keys waters this morning. Over the next couple of days, a high pushing off the Atlantic coast will exert increased control over our area. As a result, breezes will pick up modestly out of the east. Thereafter, ridging will dominate and gentle to moderate easterly breezes will continue, peaking at night and lulling in the afternoons. && .AVIATION... (06Z TAFS) Issued at 400 AM EDT Tue Sep 8 2026 Surface winds will be light and variable. VFR conditions will prevail at the island terminals today. However, weak flow and ample moisture will allow for shower and thunderstorm development near the terminals, particularly Key West. These episodes may result in bouts of sub VFR conditions and possible vicinity thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... Key West 92 82 92 82 / 30 30 30 30 Marathon 91 84 91 83 / 40 30 30 50 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...11 Aviation/Nowcasts....11 Data Acquisition.....DP Visit us on the web at weather.gov/key Follow us on Facebook and X at: www.facebook.com/nwskeywest www.x.com/nwskeywest