Routine Fire Wx Fcst (With/Without 6-10 Day Outlook)
Issued by NWS San Juan, PR
Issued by NWS San Juan, PR
331
FNCA52 TJSJ 040941
FWFSJU
Fire Weather Planning Forecast for Puerto Rico
National Weather Service San Juan PR
541 AM AST Thu Dec 4 2025
.DISCUSSION...
An induced surface trough will provide enough moisture and
cloudiness across the islands resulting in RH values from the low
50s to the upper 50s. Winds will remain from the east at 10 to 12
mph with gusty winds near the showers. Although, KDBI values
might enhance some brief fire danger threat, given the expected
weather the risk of fire weather will remain low to moderate
today.
PRZ014-050945-
Southeast Coastal Plains-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 40 30 10
Temp (24h trend) 89 (+4) 71 (-1) 89
RH % (24h trend) 52 (-8) 90 (0) 51
Wind 20ft/early(mph) E 18 G23 E 11 E 16 G21
Wind 20ft/late(mph) E 18 G23 E 11 E 16 G21
Mixing Hgt(ft-agl/msl)4760 4840
Transport Wnd (mph) E 14 E 15
Vent Rate (kt-ft) 57120 62920
Dispersion 5 5
DSI 5 3 6
RH Recovery Excellent
Remarks...None.
$$
PRZ015-050945-
Southern Hills-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Mclear Mclear
Precip Type Tstms Showers Showers
Chance Precip (%) 50 10 10
Temp (24h trend) 85 (+5) 67 (-3) 85
RH % (24h trend) 63 (-10) 96 (+2) 59
Wind 20ft/early(mph) E 13 E 10 E 12
Wind 20ft/late(mph) E 13 E 10 E 12
Mixing Hgt(ft-agl/msl)4830 5070
Transport Wnd (mph) E 14 E 15
Vent Rate (kt-ft) 57960 65910
Dispersion 5 5
DSI 5 2 5
RH Recovery Excellent
Remarks...None.
$$
PRZ016-050945-
North Coastal Plains-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 40 20 10
Temp (24h trend) 87 (+2) 71 (-1) 88
RH % (24h trend) 66 (-3) 95 (-2) 60
Wind 20ft/early(mph) E 16 G18 E 13 E 17 G19
Wind 20ft/late(mph) E 16 G18 E 13 E 17 G19
Mixing Hgt(ft-agl/msl)4000 4630
Transport Wnd (mph) E 16 E 17
Vent Rate (kt-ft) 56000 69450
Dispersion 5 5
DSI 5 4 6
RH Recovery Excellent
Remarks...None.
$$
PRZ017-050945-
Northern Hills-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Mclear Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 50 10 10
Temp (24h trend) 85 (+1) 69 (-1) 86
RH % (24h trend) 69 (0) 96 (-3) 60
Wind 20ft/early(mph) NE 13 E 12 E 14
Wind 20ft/late(mph) NE 13 E 12 E 14
Mixing Hgt(ft-agl/msl)4310 4890
Transport Wnd (mph) E 15 E 15
Vent Rate (kt-ft) 56030 63570
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
PRZ018-050945-
West Coast-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Mclear Mclear
Precip Type Tstms Showers Showers
Chance Precip (%) 70 10 20
Temp (24h trend) 89 (+4) 69 (-1) 89
RH % (24h trend) 63 (-7) 98 (+1) 59
Wind 20ft/early(mph) E 14 E 11 E 13
Wind 20ft/late(mph) E 14 E 11 E 13
Mixing Hgt(ft-agl/msl)3920 4230
Transport Wnd (mph) E 12 E 9
Vent Rate (kt-ft) 39200 33840
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
PRZ019-050945-
Eastern Interior-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 50 40 30
Temp (24h trend) 86 (+3) 69 (-2) 86
RH % (24h trend) 67 (-3) 97 (-1) 62
Wind 20ft/early(mph) E 11 E 12 E 13
Wind 20ft/late(mph) E 11 E 12 E 13
Mixing Hgt(ft-agl/msl)4480 4730
Transport Wnd (mph) E 13 E 15
Vent Rate (kt-ft) 49280 61490
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
PRZ022-050945-
Luquillo Mountain Range-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 50 50 30
Temp (24h trend) 82 (+4) 66 (-4) 81
RH % (24h trend) 73 (-4) 99 (-1) 68
Wind 20ft/early(mph) E 9 E 9 E 12
Wind 20ft/late(mph) E 9 E 9 E 12
Mixing Hgt(ft-agl/msl)3260 3850
Transport Wnd (mph) E 14 E 16
Vent Rate (kt-ft) 39120 53900
Dispersion 5 5
DSI 5 4 5
RH Recovery Excellent
Remarks...None.
$$
PRZ023-050945-
Central Mountain Range-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Mclear Mclear
Precip Type Tstms Showers Showers
Chance Precip (%) 60 10 20
Temp (24h trend) 84 (+5) 65 (-3) 84
RH % (24h trend) 67 (-7) 97 (+1) 61
Wind 20ft/early(mph) E 11 E 9 E 9
Wind 20ft/late(mph) E 11 E 9 E 9
Mixing Hgt(ft-agl/msl)4900 5180
Transport Wnd (mph) E 12 E 12
Vent Rate (kt-ft) 49000 51800
Dispersion 5 5
DSI 5 1 5
RH Recovery Excellent
Remarks...None.
$$
PRZ024-050945-
Cayey Mountain Range-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Mclear
Precip Type Tstms Showers Showers
Chance Precip (%) 60 50 20
Temp (24h trend) 82 (+4) 67 (-2) 81
RH % (24h trend) 72 (-3) 99 (0) 67
Wind 20ft/early(mph) E 10 E 8 E 11
Wind 20ft/late(mph) E 10 E 8 E 11
Mixing Hgt(ft-agl/msl)3870 4130
Transport Wnd (mph) E 15 E 16
Vent Rate (kt-ft) 50310 57820
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
PRZ025-050945-
Vieques-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 50 50 30
Temp (24h trend) 88 (+3) 72 (-2) 87
RH % (24h trend) 61 (-5) 96 (-2) 59
Wind 20ft/early(mph) E 13 G17 E 14 G19 E 16 G19
Wind 20ft/late(mph) E 13 G17 E 14 G19 E 16 G19
Mixing Hgt(ft-agl/msl)3160 3570
Transport Wnd (mph) E 17 E 17
Vent Rate (kt-ft) 47400 53550
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
PRZ026-050945-
Culebra-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 50 50 30
Temp (24h trend) 89 (+3) 72 (-4) 87
RH % (24h trend) 61 (-5) 95 (0) 58
Wind 20ft/early(mph) E 13 G17 E 14 G19 E 16 G20
Wind 20ft/late(mph) E 13 G17 E 14 G19 E 16 G20
Mixing Hgt(ft-agl/msl)3300 3630
Transport Wnd (mph) E 17 E 18
Vent Rate (kt-ft) 49500 58080
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
PRZ027-050945-
Southwest Coastal Plains and Mona Island-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Mclear Mclear
Precip Type Tstms Showers Showers
Chance Precip (%) 60 10 10
Temp (24h trend) 89 (+3) 70 (-2) 90
RH % (24h trend) 49 (-9) 93 (+6) 48
Wind 20ft/early(mph) E 19 G24 E 13 E 19 G24
Wind 20ft/late(mph) E 19 G24 E 13 E 19 G24
Mixing Hgt(ft-agl/msl)4700 4790
Transport Wnd (mph) E 12 E 15
Vent Rate (kt-ft) 47000 62270
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
VIZ001-050945-
Saint Thomas and Saint John-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 50 50 30
Temp (24h trend) 86 (+2) 70 (-6) 84
RH % (24h trend) 65 (-5) 100 (+5) 64
Wind 20ft/early(mph) E 16 G20 E 17 G22 E 16 G20
Wind 20ft/late(mph) E 16 G20 E 17 G22 E 16 G20
Mixing Hgt(ft-agl/msl)3340 3620
Transport Wnd (mph) E 20 E 21
Vent Rate (kt-ft) 56780 65160
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
VIZ002-050945-
St Croix-
541 AM AST Thu Dec 4 2025
Today Tonight Fri
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 50 50 30
Temp (24h trend) 89 (+4) 72 (-4) 87
RH % (24h trend) 60 (-10) 95 (0) 61
Wind 20ft/early(mph) E 16 G19 E 17 G21 E 16 G20
Wind 20ft/late(mph) E 16 G19 E 17 G21 E 16 G20
Mixing Hgt(ft-agl/msl)4120 4220
Transport Wnd (mph) E 20 E 22
Vent Rate (kt-ft) 70040 80180
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
$$