Spot Forecast
Issued by NWS San Juan, PR

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FNCA72 TJSJ 211112
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Spot Forecast for Bike Trail...PRFD
National Weather Service San Juan PR
712 AM AST Tue Jul 21 2026

Forecast is based on forecast start time of 0800 AST on July 21.
If conditions become unrepresentative...contact the National Weather
Service.

Please contact our office if you have questions or concerns
with this forecast at
PHONE: 787-253-4586.

.DISCUSSION...

A nearby trough will bring an increase in moisture and rainfall
activity across the region, along with a decrease in winds. Nevertheless,
due to current conditions and previous fires, the risk will remain elevated.

.REST OF TODAY...

Sky/weather.........Sunny (5-15 percent) then becoming mostly
                    cloudy (70-80 percent). Scattered showers early
                    in the afternoon. Numerous showers and isolated
                    thunderstorms late in the afternoon.
Chance of pcpn......60 percent.
Max temperature.....Around 92.
Min humidity........61 percent.
Wind (20 ft)........Northwest winds 6 to 7 mph shifting to the west
                    late in the morning, then shifting to the
                    southeast 7 to 9 mph in the afternoon. Gusty
                    and erratic winds expected near thunderstorms
                    late in the afternoon.
Mixing height.......2800 ft AGL.
Transport winds.....Northeast 5 to 8 mph shifting to the southeast
                    in the afternoon.
Smoke dispersal.....Poor (9500 knot-ft).
Dispersion..........6.
Eye level winds.....Northwest winds around 4 mph shifting to the
                    west late in the morning, then shifting to the
                    southeast up to 5 mph in the afternoon.

TIME (AST)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........16  5   5   5   70  70  70  80  80  80
Weather cov.....                SCT SCT SCT NUM NUM NUM
Weather type....                RW  RW  RW  RW  RW  RW
Tstm cov........                            ISO ISO ISO
Chc of pcpn (%).0   0   0   0   50  50  50  60  60  60
Temp............84  87  89  90  91  92  92  91  90  88
RH..............71  68  64  61  61  62  62  63  66  71
20 FT wind dir..N   N   NW  W   W   S   SE  SE  SE  SE
20 FT wind spd..7   7   6   6   7   7   8   8   9   8
20 FT wind gust.12  12  12  12  12  13  14  15  15  15
Eye lvl wnd dir.N   N   NW  W   W   S   SE  SE  SE  SE
Eye lvl wnd spd.4   4   4   4   4   4   5   5   5   5
Eye lvl wnd gst.7   7   7   7   7   8   8   9   9   9
Mix hgt (kft)...1.2 1.8 2.4 2.8 2.7 2.4 2.0 1.9 1.9 1.7
Transp wind dir.NE  NE  NE  E   E   SE  SE  SE  SE  SE
Transp wind spd.8   7   6   5   5   5   5   6   7   8
Dispersion......6   6   6   6   6   6   6   6   6   6
Vrate kt-ft/1K..10  10  10  10  10  10  10  10  10  10
Ventrate Cat....PR  PR  PR  PR  PR  PR  PR  PR  PR  PR

.TONIGHT...

Sky/weather.........Partly cloudy (35-45 percent) then becoming
                    mostly clear (5-15 percent). Isolated showers
                    early in the evening.
Chance of pcpn......20 percent.
Min temperature.....Around 74.
Max humidity........97 percent.
Wind (20 ft)........East winds 5 to 7 mph decreasing to around 5
                    mph late in the evening.
Mixing height.......200 ft AGL.
Transport winds.....East 6 to 8 mph shifting to the northeast
                    around 5 mph in the late evening and overnight,
                    then shifting to the east overnight.
Smoke dispersal.....Poor (1200 knot-ft).
Dispersion..........4.
Eye level winds.....East winds up to 4 mph decreasing to around 3
                    mph late in the evening.

TIME (AST)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........40  40  40  5   5   5   11  11  11  16  16  16
Weather cov.....ISO ISO ISO
Weather type....RW  RW  RW
Tstm cov........
Chc of pcpn (%).20  20  20  0   0   0   0   0   0   0   0   0
Temp............84  82  80  79  78  77  76  75  75  74  74  77
RH..............80  86  87  93  94  97  92  95  94  96  97  86
20 FT wind dir..SE  E   E   E   E   NE  E   E   E   E   E   E
20 FT wind spd..7   6   5   5   5   5   5   5   5   5   5   5
20 FT wind gust.13  10  9   8   8   8   9   9   9   8   8   8
Eye lvl wnd dir.SE  E   E   E   E   NE  E   E   E   E   E   E
Eye lvl wnd spd.4   4   3   3   3   3   3   3   3   3   3   3
Eye lvl wnd gst.8   6   5   5   5   5   5   5   5   5   5   5
Mix hgt (kft)...1.4 1.0 0.6 0.4 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.3
Transp wind dir.SE  E   E   E   N   N   N   E   E   E   E   E
Transp wind spd.8   7   6   6   5   5   5   5   5   5   5   5
Dispersion......6   6   2   2   2   2   2   2   2   2   2   2
Vrate kt-ft/1K..10  10  1   1   1   1   1   1   2   2   2   2
Ventrate Cat....PR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR

.WEDNESDAY...

Sky/weather.........Mostly sunny (30-40 percent). Isolated showers.
Chance of pcpn......20 percent.
Max temperature.....Around 94.
Min humidity........49 percent.
Wind (20 ft)........East winds 5 to 14 mph shifting to the
                    southeast 15 to 17 mph with gusts to around 29
                    mph late in the morning.
Mixing height.......3800 ft AGL.
Transport winds.....East 6 to 13 mph shifting to the southeast 16
                    to 20 mph in the late morning and afternoon.
Smoke dispersal.....Poor (1800 knot-ft) early in the morning
                    increasing to good (41500 knot-ft) in the
                    afternoon.
Dispersion..........4.
Eye level winds.....Southeast winds up to 8 mph shifting to the 9
                    to 10 mph with gusts to around 17 mph late in
                    the morning.

TIME (AST)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........28  28  28  29  29  29  40  40  40  40  40  40
Weather cov.....ISO ISO ISO ISO ISO ISO ISO ISO ISO ISO ISO ISO
Weather type....RW  RW  RW  RW  RW  RW  RW  RW  RW  RW  RW  RW
Tstm cov........
Chc of pcpn (%).10  10  10  10  10  10  20  20  20  20  20  20
Temp............80  83  86  89  91  92  93  94  94  93  92  89
RH..............72  67  61  57  54  52  50  49  49  50  52  57
20 FT wind dir..E   E   E   E   SE  SE  SE  SE  SE  SE  SE  SE
20 FT wind spd..5   6   7   10  14  16  17  17  16  16  15  15
20 FT wind gust.9   10  13  18  23  28  29  28  26  26  25  25
Eye lvl wnd dir.E   E   E   E   SE  SE  SE  SE  SE  SE  SE  SE
Eye lvl wnd spd.3   4   4   6   8   10  10  10  10  10  9   9
Eye lvl wnd gst.5   6   8   11  14  17  17  17  16  16  15  15
Mix hgt (kft)...0.6 1.0 1.6 2.4 3.1 3.7 3.8 3.6 3.4 3.3 3.1 2.9
Transp wind dir.E   E   E   E   SE  SE  SE  SE  SE  SE  SE  SE
Transp wind spd.6   7   9   13  16  18  20  20  18  18  17  17
Dispersion......2   2   6   6   6   6   6   6   6   6   6   6
Vrate kt-ft/1K..2   2   42  42  42  42  42  42  42  42  42  42
Ventrate Cat....PR  PR  FR  FR  FR  FR  FR  FR  FR  FR  FR  FR

$$
Forecaster...M. Marrero
Requested by...Jose M. Martinez
Type of request...WILDFIRE
.TAG 2617461.5/SJU
.DELDT 07/21/26
.FormatterVersion 2.0.0
.EMAIL josemartin@dsp.pr.gov