FNUS52 KKEY 200805 FWFKEY Fire Weather Planning Forecast for the Florida Keys National Weather Service Key West FL 405 AM EDT Thu Aug 20 2026 .Discussion... Warmer than normal weather continues while rain chances slowly increase in the coming days. Temperatures in the lower 90s are likely across the island chain while dew points stay in the mid to upper 70s. Relative humidity values are expected to recover into the mid 80s during the overnight hours, but min RH values will be able to drop into the lower 60s during the afternoon hours. In addition, collapsing winds with a light and variable flow pattern suggests that dispersion indices will be very low through the remainder of the week. FLZ076>078-202315- Monroe Upper Keys-Monroe Middle Keys-Monroe Lower Keys- Including the cities of Key Largo, Marathon, and Key West 405 AM EDT Thu Aug 20 2026 Today Tonight Fri Cloud Cover Pcldy Pcldy Pcldy Chance Precip (%) 10 0 0 Chance of Thunder (%) 10 0 0 Weather Type Tstms None None Max/Min Temp 92 82 91 Min/Max RH % 64 84 63 Wind 20ft AM (mph) Lgt/Var S 5 Wind 20ft PM (mph) Lgt/Var Lgt/Var Lgt/Var Precip Duration 1 Precip Begin 8 AM Precip End 6 PM Precip Amount 0.03 0.00 0.00 Mixing Hgt(ft-agl) 3100 1700 3000 Transport Wnd (mph) W 7 E 7 SE 6 Dispersion Index 21 7 21 Max LVORI 4 4 4 Remarks...None. $$ .FORECAST FOR DAYS 3 THROUGH 7... .FRIDAY NIGHT...Partly cloudy. Lows in the lower 80s. South winds around 5 mph. .SATURDAY...Sunny. Highs in the lower 90s. Southeast winds around 5 mph. .SATURDAY NIGHT...Mostly clear. Lows in the lower 80s. Southeast winds around 5 mph. .SUNDAY...Sunny with a slight chance of showers and thunderstorms. Highs around 90. Southeast winds around 5 mph. .SUNDAY NIGHT...Partly cloudy with a slight chance of showers and thunderstorms. Lows in the lower 80s. East winds around 5 mph. .MONDAY...Sunny with a slight chance of showers and thunderstorms. Highs around 90. Southeast winds around 5 mph. .MONDAY NIGHT...Mostly clear with a chance of showers and thunderstorms. Lows in the lower 80s. East winds around 5 mph. .TUESDAY...Sunny with a slight chance of showers and thunderstorms. Highs around 90. East winds around 5 mph. .TUESDAY NIGHT...Partly cloudy with a chance of showers and thunderstorms. Lows in the lower 80s. East winds around 10 mph. .WEDNESDAY...Mostly sunny with a slight chance of showers and thunderstorms. Highs around 90. East winds around 5 mph. $$