581
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.

$$