887
FNCA52 TJSJ 180853
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
453 AM AST THU DEC 18 2025
DISCUSSION
CALM WEATHER CONDITIONS WILL PREVAIL TODAY AS A DRIER AIR MASS
MOVES ACROSS THE ISLANDS. HOWEVER, A SURGE OF MOISTURE WILL BRING
ROUNDS OF SHOWERS LATE THIS AFTERNOON INTO THE EVENING. DURING
THIS TIME, RH AND THE KBDI ARE NOT EXPECTED TO MEET FIRE WEATHER
CRITERIA. HOWEVER, WE EXPECT EASTERLY WINDS AT 10 TO 17 MPH WITH
HIGHER GUSTS ARE ACROSS THE COASTAL SECTIONS TODAY. THE FIRE
DANGER WILL REMAIN LOW TODAY.
PRZ014-190900-
SOUTHEAST COASTAL PLAINS-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 10 10
TEMP (24H TREND) 89 (+4) 70 (-1) 88
RH % (24H TREND) 54 (-12) 93 (+4) 55
WIND 20FT/EARLY(MPH) E 14 G20 NE 12 E 16 G21
WIND 20FT/LATE(MPH) E 14 G20 NE 12 E 16 G21
MIXING HGT(FT-AGL/MSL)5070 4370
TRANSPORT WND (MPH) E 14 E 13
VENT RATE (KT-FT) 60840 48070
DISPERSION 5 5
DSI 6 3 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ015-190900-
SOUTHERN HILLS-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 10 30
TEMP (24H TREND) 85 (+4) 67 (-2) 84
RH % (24H TREND) 57 (-14) 97 (+6) 59
WIND 20FT/EARLY(MPH) E 12 NE 11 E 12
WIND 20FT/LATE(MPH) E 12 NE 11 E 12
MIXING HGT(FT-AGL/MSL)5570 4740
TRANSPORT WND (MPH) E 14 E 13
VENT RATE (KT-FT) 66840 52140
DISPERSION 5 5
DSI 5 2 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ016-190900-
NORTH COASTAL PLAINS-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 20 60 10
TEMP (24H TREND) 87 (+1) 70 (0) 86
RH % (24H TREND) 60 (-8) 99 (+5) 62
WIND 20FT/EARLY(MPH) E 16 G19 E 16 G18 E 16 G18
WIND 20FT/LATE(MPH) E 16 G19 E 16 G18 E 16 G18
MIXING HGT(FT-AGL/MSL)4440 4310
TRANSPORT WND (MPH) E 16 E 17
VENT RATE (KT-FT) 62160 64650
DISPERSION 5 5
DSI 6 5 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ017-190900-
NORTHERN HILLS-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 30 10
TEMP (24H TREND) 86 (+2) 68 (0) 85
RH % (24H TREND) 57 (-10) 99 (+4) 59
WIND 20FT/EARLY(MPH) E 14 E 14 E 13
WIND 20FT/LATE(MPH) E 14 E 14 E 13
MIXING HGT(FT-AGL/MSL)5070 4750
TRANSPORT WND (MPH) E 14 E 14
VENT RATE (KT-FT) 60840 57000
DISPERSION 5 5
DSI 5 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ018-190900-
WEST COAST-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 50 10 30
TEMP (24H TREND) 88 (+1) 69 (0) 88
RH % (24H TREND) 55 (-11) 97 (+3) 58
WIND 20FT/EARLY(MPH) E 12 E 18 E 12
WIND 20FT/LATE(MPH) E 12 E 18 E 12
MIXING HGT(FT-AGL/MSL)4080 4490
TRANSPORT WND (MPH) E 9 E 9
VENT RATE (KT-FT) 32640 35920
DISPERSION 5 5
DSI 5 3 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ019-190900-
EASTERN INTERIOR-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 50 20
TEMP (24H TREND) 85 (+3) 68 (-2) 84
RH % (24H TREND) 63 (-9) 100 (+6) 64
WIND 20FT/EARLY(MPH) E 12 E 12 E 12
WIND 20FT/LATE(MPH) E 12 E 12 E 12
MIXING HGT(FT-AGL/MSL)5170 4220
TRANSPORT WND (MPH) E 14 E 15
VENT RATE (KT-FT) 62040 54860
DISPERSION 5 5
DSI 5 3 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ022-190900-
LUQUILLO MOUNTAIN RANGE-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY MCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 60 10
TEMP (24H TREND) 80 (+3) 66 (-3) 79
RH % (24H TREND) 71 (-6) 100 (+3) 72
WIND 20FT/EARLY(MPH) E 10 E 9 E 11
WIND 20FT/LATE(MPH) E 10 E 9 E 11
MIXING HGT(FT-AGL/MSL)4050 3790
TRANSPORT WND (MPH) E 15 E 15
VENT RATE (KT-FT) 52650 49270
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ023-190900-
CENTRAL MOUNTAIN RANGE-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 50 0 30
TEMP (24H TREND) 84 (+4) 65 (-1) 83
RH % (24H TREND) 56 (-14) 99 (+6) 58
WIND 20FT/EARLY(MPH) E 10 E 13 E 9
WIND 20FT/LATE(MPH) E 10 E 13 E 9
MIXING HGT(FT-AGL/MSL)6270 5580
TRANSPORT WND (MPH) E 9 E 9
VENT RATE (KT-FT) 50160 44640
DISPERSION 5 5
DSI 5 2 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ024-190900-
CAYEY MOUNTAIN RANGE-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 50 10
TEMP (24H TREND) 81 (+4) 67 (-1) 80
RH % (24H TREND) 69 (-8) 100 (+3) 70
WIND 20FT/EARLY(MPH) E 11 NE 9 E 11
WIND 20FT/LATE(MPH) E 11 NE 9 E 11
MIXING HGT(FT-AGL/MSL)4680 4100
TRANSPORT WND (MPH) E 16 E 15
VENT RATE (KT-FT) 65520 53300
DISPERSION 5 5
DSI 5 3 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ025-190900-
VIEQUES-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS NONE
CHANCE PRECIP (%) 30 50 0
TEMP (24H TREND) 85 (0) 73 (-1) 84
RH % (24H TREND) 63 (+1) 92 (+5) 61
WIND 20FT/EARLY(MPH) E 14 G18 E 17 G21 E 14 G19
WIND 20FT/LATE(MPH) E 14 G18 E 17 G21 E 14 G19
MIXING HGT(FT-AGL/MSL)3390 3500
TRANSPORT WND (MPH) E 16 E 17
VENT RATE (KT-FT) 47460 52500
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ026-190900-
CULEBRA-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS NONE
CHANCE PRECIP (%) 30 50 0
TEMP (24H TREND) 87 (+1) 73 (-3) 85
RH % (24H TREND) 62 (0) 93 (+9) 60
WIND 20FT/EARLY(MPH) E 14 G18 E 16 G20 E 14 G19
WIND 20FT/LATE(MPH) E 14 G18 E 16 G20 E 14 G19
MIXING HGT(FT-AGL/MSL)3370 3480
TRANSPORT WND (MPH) E 15 E 16
VENT RATE (KT-FT) 43810 48720
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ027-190900-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS NONE SHOWERS
CHANCE PRECIP (%) 20 0 20
TEMP (24H TREND) 89 (+2) 69 (-3) 89
RH % (24H TREND) 53 (-10) 93 (+8) 55
WIND 20FT/EARLY(MPH) E 17 G23 E 17 G19 E 18 G23
WIND 20FT/LATE(MPH) E 17 G23 E 17 G19 E 18 G23
MIXING HGT(FT-AGL/MSL)4890 4700
TRANSPORT WND (MPH) E 14 E 12
VENT RATE (KT-FT) 58680 47000
DISPERSION 5 5
DSI 5 3 5
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ001-190900-
SAINT THOMAS AND SAINT JOHN-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 50 10
TEMP (24H TREND) 85 (0) 72 (-4) 84
RH % (24H TREND) 63 (0) 94 (+9) 61
WIND 20FT/EARLY(MPH) E 14 G19 E 16 G20 E 14 G19
WIND 20FT/LATE(MPH) E 14 G19 E 16 G20 E 14 G19
MIXING HGT(FT-AGL/MSL)3190 3460
TRANSPORT WND (MPH) E 15 E 20
VENT RATE (KT-FT) 41470 58820
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ002-190900-
ST CROIX-
453 AM AST THU DEC 18 2025
TODAY TONIGHT FRI
CLOUD COVER PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 30 10
TEMP (24H TREND) 85 (0) 72 (-3) 84
RH % (24H TREND) 65 (+2) 92 (+4) 63
WIND 20FT/EARLY(MPH) E 14 G17 E 16 G19 E 14 G19
WIND 20FT/LATE(MPH) E 14 G17 E 16 G19 E 14 G19
MIXING HGT(FT-AGL/MSL)3450 3920
TRANSPORT WND (MPH) E 18 E 21
VENT RATE (KT-FT) 55200 70560
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
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