093
FNCA52 TJSJ 081930
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST SAT AUG 8 2026
DISCUSSION
ELEVATED FIRE WEATHER CONDITIONS CONTINUE THIS AFTERNOON ACROSS
SOUTHERN AND SOUTHWESTERN PLAINS OF PUERTO RICO, WHERE CRITICALLY
DRY FUELS, EXTREME DROUGHT CONDITIONS AND LOW RELATIVE HUMIDITY
VALUES ARE SUPPORTING AN INCREASED RISK FOR WILDFIRE IGNITION AND
SPREAD. RELATIVE HUMIDITY VALUES HAVE FALLEN INTO THE LOW TO MID
50S ACROSS PORTIONS OF THE SOUTHERN COASTAL PLAINS WITH SUSTAINED
EAST WINDS OF 15 TO 20 MPH, WITH HIGHER GUSTS. ALTHOUGH ISOLATED
SHOWERS AND THUNDERSTORMS REMAIN POSSIBLE ACROSS THE INTERIOR AND
WESTERN SECTIONS OF PUERTO RICO THROUGH LATE AFTERNOON, RAINFALL
COVERAGE AND AMOUNTS ARE EXPECTED TO BE LIMITED AND INSUFFICIENT
TO PROVIDE MEANINGFUL RELIEF OVER THE SOUTHERN COASTAL PLAINS,
WHERE FUELS REMAIN CRITICALLY DRY.
THE NORTHERN PERIPHERY OF A TROPICAL WAVE LOCATED OVER THE
CARIBBEAN WATERS WILL BRING A SLIGHT INCREASE IN MOISTURE LEVELS
OVER THE SOUTHERN COASTAL PLAINS ON SUNDAY. HOWEVER, DRIER
CONDITIONS WILL PERSIST AND COMBINED WITH THE ONGOING RAINFALL
DEFICITS AND CRITICALLY DRY FUELS WILL SUPPORT AN ELEVATED TO
LOCALLY CRITICAL FIRE WEATHER THREAT EACH DAY ACROSS THE SOUTHERN
AND SOUTHWESTERN COASTAL PLAINS OF PUERTO RICO. RESIDENTS AND
VISITORS SHOULD CONTINUE TO AVOID OUTDOOR BURNING AND EXERCISE
CAUTION WITH ACTIVITIES CAPABLE OF PRODUCING SPARKS OR OPEN
FLAMES, AS FAVORABLE CONDITIONS FOR WILDFIRE IGNITION AND RAPID
SPREAD ARE EXPECTED TO PERSIST THROUGH THE WEEKEND.
PRZ014-090800-
SOUTHEAST COASTAL PLAINS-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR MCLEAR PCLDY
PRECIP TYPE NONE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 0 10 20 30
TEMP (24H TREND) 74 (-2) 92 (+1) 74 92
RH % (24H TREND) 91 (+5) 48 (-3) 92 46
WIND 20FT/EARLY(MPH) E 16 E 20 E 16 E 17
WIND 20FT/LATE(MPH) NE 12 E 21 E 12 E 18
MIXING HGT(FT-AGL/MSL) 6330 5960
TRANSPORT WND (MPH) E 25 E 23
VENT RATE (KT-FT) 139260 119200
DISPERSION 5 5
DSI 4 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ015-090800-
SOUTHERN HILLS-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 20 10 20
TEMP (24H TREND) 70 (-3) 89 (+2) 71 90
RH % (24H TREND) 98 (+7) 58 (-1) 97 54
WIND 20FT/EARLY(MPH) NE 13 E 16 E 13 E 14
WIND 20FT/LATE(MPH) NE 13 E 17 E 13 E 14
MIXING HGT(FT-AGL/MSL) 6750 6300
TRANSPORT WND (MPH) E 24 E 22
VENT RATE (KT-FT) 141750 119700
DISPERSION 5 5
DSI 3 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ016-090800-
NORTH COASTAL PLAINS-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 20 20 30
TEMP (24H TREND) 74 (-3) 91 (+1) 74 91
RH % (24H TREND) 99 (+7) 63 (-2) 99 60
WIND 20FT/EARLY(MPH) E 19 E 18 E 21 E 18
WIND 20FT/LATE(MPH) E 14 E 23 E 13 E 23
MIXING HGT(FT-AGL/MSL) 5640 6200
TRANSPORT WND (MPH) E 25 E 23
VENT RATE (KT-FT) 124080 124000
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ017-090800-
NORTHERN HILLS-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR CLEAR PCLDY
PRECIP TYPE SHOWERS TSTMS NONE TSTMS
CHANCE PRECIP (%) 10 30 0 50
TEMP (24H TREND) 72 (-1) 89 (+1) 72 90
RH % (24H TREND) 99 (+2) 67 (+3) 99 63
WIND 20FT/EARLY(MPH) E 17 E 17 E 19 E 17
WIND 20FT/LATE(MPH) E 12 E 20 E 11 E 20
MIXING HGT(FT-AGL/MSL) 5820 6700
TRANSPORT WND (MPH) E 23 E 20
VENT RATE (KT-FT) 116400 113900
DISPERSION 5 5
DSI 5 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ018-090800-
WEST COAST-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR PCLDY CLEAR PCLDY
PRECIP TYPE SHOWERS TSTMS NONE TSTMS
CHANCE PRECIP (%) 30 50 0 40
TEMP (24H TREND) 72 (-2) 92 (+1) 72 92
RH % (24H TREND) 98 (+4) 61 (-1) 98 60
WIND 20FT/EARLY(MPH) E 14 E 17 E 18 E 14
WIND 20FT/LATE(MPH) E 14 E 18 E 14 E 16
MIXING HGT(FT-AGL/MSL) 5550 5070
TRANSPORT WND (MPH) E 16 E 14
VENT RATE (KT-FT) 77700 60840
DISPERSION 5 5
DSI 3 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ019-090800-
EASTERN INTERIOR-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER PCLDY MCLEAR MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 20 20 30
TEMP (24H TREND) 72 (-3) 90 (+1) 72 91
RH % (24H TREND) 98 (+6) 62 (+1) 98 57
WIND 20FT/EARLY(MPH) E 13 E 16 E 14 E 13
WIND 20FT/LATE(MPH) E 14 E 16 E 14 E 14
MIXING HGT(FT-AGL/MSL) 6990 6540
TRANSPORT WND (MPH) E 23 E 22
VENT RATE (KT-FT) 139800 124260
DISPERSION 5 5
DSI 4 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ022-090800-
LUQUILLO MOUNTAIN RANGE-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 20 20 30
TEMP (24H TREND) 70 (-3) 86 (+3) 70 86
RH % (24H TREND) 100 (+6) 69 (-3) 100 64
WIND 20FT/EARLY(MPH) E 11 E 13 E 12 E 12
WIND 20FT/LATE(MPH) E 12 E 14 E 12 E 13
MIXING HGT(FT-AGL/MSL) 5390 5450
TRANSPORT WND (MPH) E 24 E 22
VENT RATE (KT-FT) 113190 103550
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ023-090800-
CENTRAL MOUNTAIN RANGE-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR CLEAR PCLDY
PRECIP TYPE SHOWERS TSTMS NONE TSTMS
CHANCE PRECIP (%) 30 50 0 50
TEMP (24H TREND) 68 (-3) 87 (+3) 69 88
RH % (24H TREND) 99 (+3) 68 (+2) 99 65
WIND 20FT/EARLY(MPH) E 12 E 13 E 16 E 11
WIND 20FT/LATE(MPH) E 11 E 16 E 10 E 13
MIXING HGT(FT-AGL/MSL) 6950 7810
TRANSPORT WND (MPH) E 22 E 15
VENT RATE (KT-FT) 132050 101530
DISPERSION 5 5
DSI 2 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ024-090800-
CAYEY MOUNTAIN RANGE-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 20 20 20 40
TEMP (24H TREND) 71 (-2) 85 (+1) 71 86
RH % (24H TREND) 100 (+4) 70 (+4) 100 63
WIND 20FT/EARLY(MPH) NE 11 E 13 E 12 E 13
WIND 20FT/LATE(MPH) NE 11 E 16 E 11 E 14
MIXING HGT(FT-AGL/MSL) 6180 6040
TRANSPORT WND (MPH) E 25 E 24
VENT RATE (KT-FT) 135960 126840
DISPERSION 5 5
DSI 4 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ025-090800-
VIEQUES-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 20 20 30
TEMP (24H TREND) 77 (-3) 91 (+1) 79 91
RH % (24H TREND) 92 (+9) 61 (-3) 92 59
WIND 20FT/EARLY(MPH) E 18 E 17 E 17 E 16
WIND 20FT/LATE(MPH) E 18 E 17 E 17 E 14
MIXING HGT(FT-AGL/MSL) 3230 3100
TRANSPORT WND (MPH) E 24 E 23
VENT RATE (KT-FT) 67830 62000
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ026-090800-
CULEBRA-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 20 20 30
TEMP (24H TREND) 78 (-3) 91 (+2) 78 91
RH % (24H TREND) 94 (+10) 63 (-6) 95 61
WIND 20FT/EARLY(MPH) E 17 E 17 E 17 E 17
WIND 20FT/LATE(MPH) E 18 E 17 E 17 E 14
MIXING HGT(FT-AGL/MSL) 3320 3080
TRANSPORT WND (MPH) E 25 E 22
VENT RATE (KT-FT) 73040 58520
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ027-090800-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR CLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 10 30 0 20
TEMP (24H TREND) 73 (-3) 92 (+1) 74 92
RH % (24H TREND) 93 (+5) 53 (-2) 93 51
WIND 20FT/EARLY(MPH) E 14 E 20 E 21 E 19
WIND 20FT/LATE(MPH) E 11 E 25 E 14 E 21
MIXING HGT(FT-AGL/MSL) 6420 5710
TRANSPORT WND (MPH) E 20 E 22
VENT RATE (KT-FT) 109140 108490
DISPERSION 5 5
DSI 3 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ001-090800-
SAINT THOMAS AND SAINT JOHN-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 10 20 20
TEMP (24H TREND) 77 (-3) 90 (+3) 78 89
RH % (24H TREND) 95 (+12) 65 (-4) 95 62
WIND 20FT/EARLY(MPH) E 18 E 18 E 19 E 17
WIND 20FT/LATE(MPH) E 18 E 17 E 18 E 14
MIXING HGT(FT-AGL/MSL) 3290 3030
TRANSPORT WND (MPH) E 26 E 22
VENT RATE (KT-FT) 75670 57570
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ002-090800-
ST CROIX-
330 PM AST SAT AUG 8 2026
TONIGHT SUN SUN NIGHT MON
CLOUD COVER MCLEAR PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 20 20 10 30
TEMP (24H TREND) 77 (-3) 90 (+2) 77 90
RH % (24H TREND) 95 (+12) 64 (-4) 94 62
WIND 20FT/EARLY(MPH) E 18 E 18 E 17 E 16
WIND 20FT/LATE(MPH) E 18 E 18 E 17 E 14
MIXING HGT(FT-AGL/MSL) 5210 5380
TRANSPORT WND (MPH) E 28 E 23
VENT RATE (KT-FT) 125040 107600
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
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