395
FNCA52 TJSJ 181930
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST WED MAR 18 2026
DISCUSSION
FROM LATE MORNING INTO EARLY AFTERNOON, SOME SURFACE STATIONS,
ESPECIALLY ACROSS SOUTHWESTERN PUERTO RICO, REPORTED MINIMUM
RELATIVE HUMIDITY IN THE LOW TO MID-50% RANGE. SUSTAINED WINDS
RANGED FROM 10 TO 18 MPH, WITH OCCASIONAL GUSTS OF 22 TO 27 MPH.
RELATIVE HUMIDITY IS EXPECTED TO INCREASE THROUGH THE AFTERNOON,
REDUCING THE OVERALL RISK. A RFD WILL NOT BE ISSUED AT THIS TIME,
HOWEVER, PARTNERS SHOULD CONTINUE MONITORING CONDITIONS ON
THURSDAY, AS SIMILAR WEATHER IS EXPECTED. BY LATE WEEK INTO THE
WEEKEND, A FRONTAL BOUNDARY AND ASSOCIATED TROUGH WILL BRING
INCREASED MOISTURE TO THE AREA.
PRZ014-190800-
SOUTHEAST COASTAL PLAINS-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 50 60 10 30
TEMP (24H TREND) 68 (-3) 86 (+1) 68 86
RH % (24H TREND) 87 (+1) 50 (-5) 93 52
WIND 20FT/EARLY(MPH) E 14 E 12 E 10 E 11
WIND 20FT/LATE(MPH) E 11 SE 13 E 10 SE 11
MIXING HGT(FT-AGL/MSL) 5550 4700
TRANSPORT WND (MPH) E 16 SE 10
VENT RATE (KT-FT) 77700 42300
DISPERSION 5 5
DSI 5 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ015-190800-
SOUTHERN HILLS-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 0 20
TEMP (24H TREND) 64 (-4) 83 (+3) 64 83
RH % (24H TREND) 95 (+5) 58 (-1) 97 60
WIND 20FT/EARLY(MPH) E 12 E 11 E 10 SE 10
WIND 20FT/LATE(MPH) E 11 SE 11 E 8 SE 10
MIXING HGT(FT-AGL/MSL) 6280 5480
TRANSPORT WND (MPH) E 15 SE 10
VENT RATE (KT-FT) 81640 49320
DISPERSION 5 5
DSI 4 6 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ016-190800-
NORTH COASTAL PLAINS-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 30 40 10 60
TEMP (24H TREND) 67 (-3) 86 (0) 66 87
RH % (24H TREND) 96 (+4) 55 (-1) 99 54
WIND 20FT/EARLY(MPH) E 13 E 12 SE 10 SE 11
WIND 20FT/LATE(MPH) SE 12 E 14 SE 6 SE 13
MIXING HGT(FT-AGL/MSL) 5980 5500
TRANSPORT WND (MPH) E 14 SE 8
VENT RATE (KT-FT) 71760 38500
DISPERSION 5 5
DSI 4 6 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ017-190800-
NORTHERN HILLS-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER MCLEAR PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 20 60 20 70
TEMP (24H TREND) 65 (-3) 85 (+1) 64 86
RH % (24H TREND) 94 (+3) 55 (+3) 98 54
WIND 20FT/EARLY(MPH) SE 11 E 10 SE 9 SE 8
WIND 20FT/LATE(MPH) SE 11 E 12 SE 5 SE 8
MIXING HGT(FT-AGL/MSL) 6770 5670
TRANSPORT WND (MPH) E 12 SE 7
VENT RATE (KT-FT) 67700 34020
DISPERSION 5 5
DSI 3 6 2 5
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ018-190800-
WEST COAST-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 20 20 0 20
TEMP (24H TREND) 65 (-4) 87 (+1) 67 87
RH % (24H TREND) 92 (+4) 56 (0) 96 56
WIND 20FT/EARLY(MPH) E 18 E 13 E 12 SE 12
WIND 20FT/LATE(MPH) E 14 SE 13 E 11 SE 14
MIXING HGT(FT-AGL/MSL) 5180 4960
TRANSPORT WND (MPH) SE 12 SE 13
VENT RATE (KT-FT) 51800 54560
DISPERSION 5 5
DSI 5 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ019-190800-
EASTERN INTERIOR-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 60 60 10 40
TEMP (24H TREND) 66 (-3) 83 (+1) 65 84
RH % (24H TREND) 97 (+4) 59 (-1) 98 58
WIND 20FT/EARLY(MPH) E 14 SE 12 SE 11 SE 11
WIND 20FT/LATE(MPH) E 13 SE 12 SE 9 SE 12
MIXING HGT(FT-AGL/MSL) 6580 5970
TRANSPORT WND (MPH) SE 15 SE 12
VENT RATE (KT-FT) 85540 59700
DISPERSION 5 5
DSI 4 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ022-190800-
LUQUILLO MOUNTAIN RANGE-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 60 60 30 40
TEMP (24H TREND) 64 (-3) 79 (+2) 64 79
RH % (24H TREND) 98 (+3) 66 (-1) 100 65
WIND 20FT/EARLY(MPH) E 12 E 11 SE 10 SE 10
WIND 20FT/LATE(MPH) E 11 SE 11 SE 6 SE 11
MIXING HGT(FT-AGL/MSL) 4490 4480
TRANSPORT WND (MPH) SE 16 S 13
VENT RATE (KT-FT) 62860 49280
DISPERSION 5 5
DSI 6 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ023-190800-
CENTRAL MOUNTAIN RANGE-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER MCLEAR PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 10 50 0 50
TEMP (24H TREND) 62 (-4) 83 (+3) 62 83
RH % (24H TREND) 96 (+4) 58 (+1) 99 57
WIND 20FT/EARLY(MPH) E 11 SE 10 SE 6 SE 10
WIND 20FT/LATE(MPH) E 9 SE 10 SE 6 SE 12
MIXING HGT(FT-AGL/MSL) 7290 5950
TRANSPORT WND (MPH) SE 12 SE 10
VENT RATE (KT-FT) 72900 53550
DISPERSION 5 5
DSI 2 6 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ024-190800-
CAYEY MOUNTAIN RANGE-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 60 60 20 50
TEMP (24H TREND) 64 (-3) 78 (+1) 64 78
RH % (24H TREND) 99 (+2) 67 (+2) 98 68
WIND 20FT/EARLY(MPH) E 10 E 10 SE 8 SE 9
WIND 20FT/LATE(MPH) E 10 SE 10 E 6 SE 9
MIXING HGT(FT-AGL/MSL) 5380 4900
TRANSPORT WND (MPH) SE 16 S 12
VENT RATE (KT-FT) 75320 49000
DISPERSION 5 5
DSI 4 6 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ025-190800-
VIEQUES-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 50 40 20 40
TEMP (24H TREND) 71 (-2) 85 (0) 71 85
RH % (24H TREND) 88 (+2) 57 (+1) 88 58
WIND 20FT/EARLY(MPH) E 16 E 14 E 12 SE 13
WIND 20FT/LATE(MPH) E 16 SE 13 SE 11 SE 12
MIXING HGT(FT-AGL/MSL) 3780 3410
TRANSPORT WND (MPH) SE 16 SE 14
VENT RATE (KT-FT) 52920 40920
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ026-190800-
CULEBRA-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 40 20 40
TEMP (24H TREND) 72 (-2) 85 (0) 72 85
RH % (24H TREND) 91 (+6) 58 (-1) 89 58
WIND 20FT/EARLY(MPH) E 16 E 14 E 13 SE 13
WIND 20FT/LATE(MPH) E 16 SE 14 SE 12 SE 13
MIXING HGT(FT-AGL/MSL) 3580 3470
TRANSPORT WND (MPH) E 18 SE 15
VENT RATE (KT-FT) 57280 45110
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ027-190800-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER MCLEAR MCLEAR CLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 0 20 0 10
TEMP (24H TREND) 67 (-4) 87 (+1) 69 87
RH % (24H TREND) 89 (+6) 47 (-6) 96 46
WIND 20FT/EARLY(MPH) E 23 E 17 E 16 E 14
WIND 20FT/LATE(MPH) E 18 SE 17 E 13 SE 16
MIXING HGT(FT-AGL/MSL) 5310 5000
TRANSPORT WND (MPH) SE 17 SE 12
VENT RATE (KT-FT) 79650 50000
DISPERSION 5 5
DSI 5 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ001-190800-
SAINT THOMAS AND SAINT JOHN-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 40 30 20 40
TEMP (24H TREND) 72 (-3) 85 (+1) 71 85
RH % (24H TREND) 89 (+7) 56 (-3) 90 57
WIND 20FT/EARLY(MPH) E 17 E 16 E 13 SE 13
WIND 20FT/LATE(MPH) E 17 SE 14 SE 13 SE 13
MIXING HGT(FT-AGL/MSL) 3630 3480
TRANSPORT WND (MPH) E 18 SE 16
VENT RATE (KT-FT) 58080 48720
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ002-190800-
ST CROIX-
330 PM AST WED MAR 18 2026
TONIGHT THU THU NIGHT FRI
CLOUD COVER PCLDY PCLDY PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 30 20 40
TEMP (24H TREND) 70 (-4) 86 (+1) 71 86
RH % (24H TREND) 91 (+8) 58 (0) 89 58
WIND 20FT/EARLY(MPH) E 16 E 16 E 12 SE 13
WIND 20FT/LATE(MPH) E 16 E 16 E 12 SE 13
MIXING HGT(FT-AGL/MSL) 4800 4700
TRANSPORT WND (MPH) E 18 SE 17
VENT RATE (KT-FT) 76800 70500
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
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