Routine Fire Wx Fcst (With/Without 6-10 Day Outlook)
Issued by NWS San Juan, PR
Issued by NWS San Juan, PR
598
FNCA52 TJSJ 170858
FWFSJU
Fire Weather Planning Forecast for Puerto Rico
National Weather Service San Juan PR
458 AM AST Tue Jun 17 2025
.DISCUSSION...
Fire weather conditions are expected to deteriorate today, Tuesday,
as winds increase and a gradual decrease in moisture unfolds across
the region, following the relatively moister conditions observed on
Monday. The southern coastal plains are forecast to experience the
lowest relative humidity values, increasing the risk of fire
development and spread.
The 30-day rainfall percent of normal has declined to between 10-50%
across the southern coastal plains, resulting in increasing areal
coverage of drying soils. With dry fuels already in place, the
combination of strengthening winds and decreasing humidity is
likely to promote more favorable conditions for enhanced wildfire
potential, particularly across wind-prone areas.
Fire weather indices further highlight the growing concern. In Cabo
Rojo, the Keetch-Byram Drought Index (KBDI) is currently 586, with 1-
hour fuel moisture at 10% and 10-hour fuel moisture at 12%. In
Guanica, the KBDI is even higher at 622, with 1-hour fuel moisture
at 11% and 10-hour fuel moisture at 13%. KBDI values continue to
increase, indicating persistent and deepening dryness in the fuel
layers. The low 1-hour and 10-hour fuel moisture values confirm that
fine and small-diameter fuels are critically dry and receptive to
rapid spread.
Given these evolving conditions, a Fire Danger Statement is in
effect for the southern coastal plains and hills of Puerto Rico.
Residents and land management officials should continue to exercise
caution and follow any guidance in place. Refer to the latest Fire
Danger Statement (RFDSJU) for more information.
PRZ014-180900-
Southeast Coastal Plains-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 20 20 10
Temp (24h trend) 92 (+3) 73 (-3) 92
RH % (24h trend) 47 (-15) 88 (0) 45
Wind 20ft/early(mph) E 19 G24 E 14 G17 E 19 G25
Wind 20ft/late(mph) E 19 G24 E 14 G17 E 19 G25
Mixing Hgt(ft-agl/msl)4980 5010
Transport Wnd (mph) E 20 E 20
Vent Rate (kt-ft) 84660 85170
Dispersion 5 5
DSI 6 4 6
RH Recovery Excellent
Remarks...None.
$$
PRZ015-180900-
Southern Hills-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 20 20 20
Temp (24h trend) 88 (+5) 70 (-3) 87
RH % (24h trend) 58 (-12) 97 (+5) 57
Wind 20ft/early(mph) E 14 E 12 E 14
Wind 20ft/late(mph) E 14 E 12 E 14
Mixing Hgt(ft-agl/msl)5420 5290
Transport Wnd (mph) E 18 E 17
Vent Rate (kt-ft) 86720 79350
Dispersion 5 5
DSI 6 3 6
RH Recovery Excellent
Remarks...None.
$$
PRZ016-180900-
North Coastal Plains-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Mclear Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 40 0 20
Temp (24h trend) 89 (+2) 73 (-3) 89
RH % (24h trend) 63 (-6) 98 (+3) 62
Wind 20ft/early(mph) E 21 G23 E 19 E 20 G23
Wind 20ft/late(mph) E 21 G23 E 19 E 20 G23
Mixing Hgt(ft-agl/msl)4880 4760
Transport Wnd (mph) E 20 E 18
Vent Rate (kt-ft) 82960 76160
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
PRZ017-180900-
Northern Hills-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Mclear Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 30 0 20
Temp (24h trend) 87 (+2) 71 (-2) 87
RH % (24h trend) 64 (-7) 100 (+3) 63
Wind 20ft/early(mph) E 19 E 17 E 18
Wind 20ft/late(mph) E 19 E 17 E 18
Mixing Hgt(ft-agl/msl)5880 5530
Transport Wnd (mph) E 15 E 15
Vent Rate (kt-ft) 76440 71890
Dispersion 5 5
DSI 6 5 6
RH Recovery Excellent
Remarks...None.
$$
PRZ018-180900-
West Coast-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Tstms Showers Showers
Chance Precip (%) 60 40 30
Temp (24h trend) 91 (+2) 70 (-3) 91
RH % (24h trend) 59 (-8) 98 (+4) 58
Wind 20ft/early(mph) E 14 E 19 E 16
Wind 20ft/late(mph) E 14 E 19 E 16
Mixing Hgt(ft-agl/msl)5170 4530
Transport Wnd (mph) E 12 E 12
Vent Rate (kt-ft) 51700 45300
Dispersion 5 5
DSI 5 5 6
RH Recovery Excellent
Remarks...None.
$$
PRZ019-180900-
Eastern Interior-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 30 20 20
Temp (24h trend) 88 (+3) 71 (-3) 87
RH % (24h trend) 62 (-8) 99 (+4) 62
Wind 20ft/early(mph) E 13 E 13 E 14
Wind 20ft/late(mph) E 13 E 13 E 14
Mixing Hgt(ft-agl/msl)5480 5250
Transport Wnd (mph) E 17 E 18
Vent Rate (kt-ft) 82200 84000
Dispersion 5 5
DSI 6 4 6
RH Recovery Excellent
Remarks...None.
$$
PRZ022-180900-
Luquillo Mountain Range-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 40 20 30
Temp (24h trend) 82 (+3) 69 (-3) 82
RH % (24h trend) 73 (-7) 100 (+2) 72
Wind 20ft/early(mph) E 12 E 10 E 13
Wind 20ft/late(mph) E 12 E 10 E 13
Mixing Hgt(ft-agl/msl)4460 4330
Transport Wnd (mph) E 17 E 18
Vent Rate (kt-ft) 66900 69280
Dispersion 5 5
DSI 6 5 6
RH Recovery Excellent
Remarks...None.
$$
PRZ023-180900-
Central Mountain Range-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Tstms Showers Showers
Chance Precip (%) 50 20 20
Temp (24h trend) 85 (+4) 67 (-4) 85
RH % (24h trend) 62 (-12) 100 (+3) 63
Wind 20ft/early(mph) E 12 E 12 E 11
Wind 20ft/late(mph) E 12 E 12 E 11
Mixing Hgt(ft-agl/msl)6830 6470
Transport Wnd (mph) E 12 E 12
Vent Rate (kt-ft) 68300 64700
Dispersion 5 5
DSI 5 3 5
RH Recovery Excellent
Remarks...None.
$$
PRZ024-180900-
Cayey Mountain Range-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 20 20 20
Temp (24h trend) 83 (+3) 69 (-3) 83
RH % (24h trend) 69 (-9) 100 (+1) 68
Wind 20ft/early(mph) E 13 E 10 E 13
Wind 20ft/late(mph) E 13 E 10 E 13
Mixing Hgt(ft-agl/msl)4880 4800
Transport Wnd (mph) E 20 E 20
Vent Rate (kt-ft) 82960 81600
Dispersion 5 5
DSI 6 4 6
RH Recovery Excellent
Remarks...None.
$$
PRZ025-180900-
Vieques-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Mclear Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 10 20 10
Temp (24h trend) 87 (+1) 75 (-2) 86
RH % (24h trend) 62 (-6) 89 (+1) 64
Wind 20ft/early(mph) E 16 G20 E 17 G21 E 17 G21
Wind 20ft/late(mph) E 16 G20 E 17 G21 E 17 G21
Mixing Hgt(ft-agl/msl)3400 3530
Transport Wnd (mph) E 20 E 22
Vent Rate (kt-ft) 57800 67070
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
PRZ026-180900-
Culebra-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Pcldy
Precip Type Showers Showers Showers
Chance Precip (%) 30 20 20
Temp (24h trend) 88 (+1) 76 (-2) 88
RH % (24h trend) 62 (-6) 94 (+5) 61
Wind 20ft/early(mph) E 16 G19 E 17 G21 E 17 G21
Wind 20ft/late(mph) E 16 G19 E 17 G21 E 17 G21
Mixing Hgt(ft-agl/msl)3400 3490
Transport Wnd (mph) E 20 E 21
Vent Rate (kt-ft) 57800 62820
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
PRZ027-180900-
Southwest Coastal Plains and Mona Island-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Pcldy Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 20 10 20
Temp (24h trend) 92 (+3) 74 (-2) 92
RH % (24h trend) 50 (-13) 88 (+3) 50
Wind 20ft/early(mph) E 21 G28 E 17 G20 E 23 G29
Wind 20ft/late(mph) E 21 G28 E 17 G20 E 23 G29
Mixing Hgt(ft-agl/msl)5400 4820
Transport Wnd (mph) E 17 E 20
Vent Rate (kt-ft) 81000 81940
Dispersion 5 5
DSI 6 5 6
RH Recovery Excellent
Remarks...None.
$$
VIZ001-180900-
Saint Thomas and Saint John-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Pcldy Mclear Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 20 10 10
Temp (24h trend) 86 (+1) 75 (-3) 86
RH % (24h trend) 66 (-4) 94 (+5) 66
Wind 20ft/early(mph) E 16 G20 E 17 G21 E 17 G21
Wind 20ft/late(mph) E 16 G20 E 17 G21 E 17 G21
Mixing Hgt(ft-agl/msl)3280 3480
Transport Wnd (mph) E 21 E 22
Vent Rate (kt-ft) 59040 66120
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
VIZ002-180900-
St Croix-
458 AM AST Tue Jun 17 2025
Today Tonight Wed
Cloud Cover Mclear Mclear Mclear
Precip Type Showers Showers Showers
Chance Precip (%) 10 10 0
Temp (24h trend) 87 (+1) 76 (-2) 87
RH % (24h trend) 63 (-6) 88 (+1) 64
Wind 20ft/early(mph) E 16 G20 E 17 G20 E 16 G21
Wind 20ft/late(mph) E 16 G20 E 17 G20 E 16 G21
Mixing Hgt(ft-agl/msl)4290 4480
Transport Wnd (mph) E 23 E 24
Vent Rate (kt-ft) 85800 94080
Dispersion 5 5
DSI 6 6 6
RH Recovery Excellent
Remarks...None.
$$
$$