Spot Forecast
Issued by NWS Miami, FL

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606
FNUS72 KMFL 211504
FWSMFL

Spot Forecast for Big Cypress Rx...Seminole Tribe
National Weather Service Miami FL
Issued by National Weather Service Key West FL
1104 AM EDT Tue Jul 21 2026

Forecast is based on ignition time of 1000 EDT on July 21.
If conditions become unrepresentative...contact the National Weather
Service.

Please contact our office at (305) 229-4522, if you have questions
or concerns with this forecast.

.DISCUSSION...
Dry weather conditions are expected through the early afternoon
before some late day showers and storms pop up along the west
coast sea breeze. Storm initiation will concentrate across Hendry
and northern portions of Collier County, accompanied by general
storm motion to the north to northeast. However, a minority of CAM
guidance suggests some storms may back-build to the south towards
the site later this afternoon/evening (5-8 PM). Winds will also
be gusty for another day, which is likely to lead to excellent
dispersion indices above 70-80 which can result in uncontrollable
fire behavior. Winds will decrease for tomorrow, allowing
dispersions to fall back into the good range and conditions will
be mostly dry again tomorrow at least through the early afternoon
hours.


.REST OF TODAY...

Sky/weather.........Mostly sunny (35-45 percent). Slight chance of
                    showers and thunderstorms early in the
                    afternoon. Chance of showers and thunderstorms
                    late in the afternoon.
Chance of pcpn......40 percent.
Max temperature.....Around 96.
Min humidity........49 percent.
Wind (20 ft)........South winds 5 to 6 mph in the late morning and
                    afternoon becoming light. Gusty and erratic
                    winds expected near thunderstorms late in the
                    afternoon.
Mixing height.......5800 ft AGL.
Transport winds.....South 8 to 16 mph.
Dispersion index....53 increasing to 75 late in the morning, then
                    decreasing to 65 early in the afternoon
                    decreasing to 49 late in the afternoon
                    decreasing to 32.
LVORI...............2.

TIME (EDT)      10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........21  36  26  29  26  38  47  62
Weather cov.....                SCH SCH CHC CHC
Weather type....                RW  RW  RW  RW
Tstm cov........                SCH SCH CHC CHC
Chc of pcpn (%).0   0   0   0   20  20  30  40
Temp............87  89  91  92  94  94  93  94
RH..............72  66  58  54  49  49  51  51
20 FT wind dir..S   S   S   S   S   S   S   S
20 FT wind spd..6   6   6   6   5   5   5   3
20 FT wind gust.16  16  16  16  16  16  15  14
Mix hgt (kft)...2.7 3.7 4.7 5.5 5.8 5.6 4.9 4.0
Transp wind dir.S   S   S   S   S   S   S   S
Transp wind spd.15  16  15  13  10  9   8   8
Dispersion idx..53  71  79  78  68  61  49  32
LVORI...........3   1   1   1   1   1   1   1

.TONIGHT...

Sky/weather.........Mostly cloudy (55-65 percent) then becoming
                    partly cloudy (40-50 percent) then becoming
                    mostly cloudy (55-65 percent) then becoming
                    partly cloudy (25-35 percent). Chance of
                    showers and thunderstorms early in the evening,
                    then slight chance of showers and thunderstorms
                    early in the evening.
Chance of pcpn......40 percent.
Min temperature.....Around 72.
Max humidity........97 percent.
Wind (20 ft)........Light winds. Gusty and erratic winds expected
                    near thunderstorms early in the evening.
Mixing height.......300 ft AGL.
Transport winds.....South 6 to 8 mph.
Dispersion index....26 decreasing to 3.
LVORI...............5.

TIME (EDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........58  43  68  52  45  23  15  23  27  40  18  20
Weather cov.....CHC CHC SCH SCH
Weather type....RW  RW  RW  RW
Tstm cov........CHC CHC SCH SCH
Chc of pcpn (%).40  30  20  20  10  0   0   0   0   0   0   0
Temp............91  89  86  81  79  77  76  76  75  74  74  73
RH..............56  61  68  79  85  90  94  90  94  97  93  97
20 FT wind dir..S   S   S   S   S   E   SE  SE  SE  SE  SE  E
20 FT wind spd..3   2   2   1   1   1   1   1   2   1   2   1
20 FT wind gust.12  9   7   6   5   3   5   6   6   5   6   5
Mix hgt (kft)...2.8 1.6 0.6 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4
Transp wind dir.S   S   S   S   S   S   S   SE  SE  SE  SE  SE
Transp wind spd.8   7   7   7   6   6   6   6   6   6   6   6
Dispersion idx..26  16  3   3   3   3   3   3   3   3   3   3
LVORI...........2   2   3   4   5   6   6   6   6   7   7   8

.WEDNESDAY...

Sky/weather.........Sunny (15-25 percent) then becoming partly
                    sunny (45-55 percent). Chance of showers and
                    thunderstorms late in the afternoon.
Chance of pcpn......50 percent.
Max temperature.....Around 94.
Min humidity........54 percent.
Wind (20 ft)........Light winds. Gusty and erratic winds expected
                    near thunderstorms late in the afternoon.
Mixing height.......5400 ft AGL.
Transport winds.....Southeast 6 to 8 mph.
Dispersion index....5 increasing to 14 late in the morning, then
                    increasing to 28 late in the morning increasing
                    to 46 late in the morning decreasing to 37.
LVORI...............5.

TIME (EDT)      6 AM   8 AM   10 AM  NOON   2 PM   4 PM
Sky (%).........19     13     13     16     14     53
Weather cov.....                            CHANCE CHANCE
Weather type....NONE   NONE   NONE   NONE   RNSHWR RNSHWR
Tstm cov........                            CHANCE CHANCE
Chc of pcpn (%).0      0      0      0      40     50
Temp............73     75     86     90     92     92
RH..............97     100    75     62     56     56
20 FT wind dir..E      SE     SE     SE     SE     SE
20 FT wind spd..1      2      3      3      3      3
20 FT wind gust.5      6      9      12     12     12
Mix hgt (ft)....300    500    2900   4800   5400   4900
Transport wind..SE 6   SE 6   SE 8   SE 8   SE 7   SE 7
Dispersion idx..3      6      28     49     47     39
LVORI...........8      8      3      1      1      1

$$
Forecaster...Rothwell
Requested by...Mike Lightsey
Type of request...PRESCRIBED
.TAG 2617867.0/MFL
.DELDT 07/21/26
.FormatterVersion 2.0.0