Routine Fire Wx Fcst (With/Without 6-10 Day Outlook)
Issued by NWS San Juan, PR
Issued by NWS San Juan, PR
132
FNCA52 TJSJ 151930
FWFSJU
Fire Weather Planning Forecast for Puerto Rico
National Weather Service San Juan PR
330 PM AST Sat Aug 15 2026
...RED FLAG WARNING UNTIL 5 PM AST THIS AFTERNOON FOR PORTIONS OF
PUERTO RICO...
.DISCUSSION...
Elevated fire danger continues today as minimum relative
humidities remain around mid 40s to low 50s, particularly across
the coastal plains and hills of southern Puerto Rico and Vieques.
That combined with breezy to windy conditions are elevating the
risk of fire spread. A Fire Danger Statement remains in effect
across portions of Puerto Rico, Culebra, and the U.S. Virgin
Islands until 5 PM AST this afternoon, while a Red Flag Warning
was issued for the coastal plains and hills of southern Puerto
Rico and Vieques.
The northern periphery of an approaching tropical wave should
continue to approach, slightly increasing the moisture content
across the area. Nonetheless, the dry conditions will persist
until then.
PRZ014-160800-
Southeast Coastal Plains-
330 PM AST Sat Aug 15 2026
...RED FLAG WARNING IN EFFECT UNTIL 5 PM AST THIS AFTERNOON...
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Mclear
Precip Type Tstms Showers None Showers
Chance Precip (%) 40 30 0 10
Temp (24h trend) 75 (-3) 89 (-2) 75 92
RH % (24h trend) 94 (+9) 59 (+3) 91 52
Wind 20ft/early(mph) E 16 E 16 G23 E 14 E 17
Wind 20ft/late(mph) E 12 E 17 G26 NE 11 E 18
Mixing Hgt(ft-agl/msl) 4770 4920
Transport Wnd (mph) E 20 E 16
Vent Rate (kt-ft) 81090 68880
Dispersion 5 5
DSI 5 6 4 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ015-160800-
Southern Hills-
330 PM AST Sat Aug 15 2026
...RED FLAG WARNING IN EFFECT UNTIL 5 PM AST THIS AFTERNOON...
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Mclear
Precip Type Tstms Showers Showers Showers
Chance Precip (%) 40 30 0 10
Temp (24h trend) 71 (-4) 89 (+2) 71 90
RH % (24h trend) 99 (+8) 62 (+1) 97 57
Wind 20ft/early(mph) NE 18 E 16 E 13 E 13
Wind 20ft/late(mph) E 16 E 16 NE 13 E 13
Mixing Hgt(ft-agl/msl) 5700 5320
Transport Wnd (mph) E 18 E 15
Vent Rate (kt-ft) 91200 69160
Dispersion 5 5
DSI 4 6 3 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ016-160800-
North Coastal Plains-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Pcldy
Precip Type Tstms Tstms Showers Tstms
Chance Precip (%) 60 50 10 30
Temp (24h trend) 75 (-3) 89 (-1) 74 91
RH % (24h trend) 99 (+7) 65 (-2) 96 59
Wind 20ft/early(mph) E 24 E 18 E 21 E 16
Wind 20ft/late(mph) E 18 E 23 E 13 E 20
Mixing Hgt(ft-agl/msl) 4750 5010
Transport Wnd (mph) E 21 E 16
Vent Rate (kt-ft) 85500 70140
Dispersion 5 5
DSI 6 6 6 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ017-160800-
Northern Hills-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Pcldy
Precip Type Tstms Tstms Showers Tstms
Chance Precip (%) 40 50 10 50
Temp (24h trend) 72 (-3) 89 (+1) 72 90
RH % (24h trend) 100 (+3) 65 (0) 99 60
Wind 20ft/early(mph) E 21 E 17 E 19 E 13
Wind 20ft/late(mph) E 16 NE 20 E 11 NE 17
Mixing Hgt(ft-agl/msl) 5680 5900
Transport Wnd (mph) E 17 E 12
Vent Rate (kt-ft) 85200 59000
Dispersion 5 5
DSI 6 6 4 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ018-160800-
West Coast-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Mclear Pcldy Mclear Pcldy
Precip Type Showers Tstms Showers Tstms
Chance Precip (%) 10 60 10 40
Temp (24h trend) 74 (-2) 89 (-3) 72 93
RH % (24h trend) 96 (+5) 68 (+7) 98 57
Wind 20ft/early(mph) E 26 E 19 E 17 E 13
Wind 20ft/late(mph) E 20 E 18 E 16 SE 13
Mixing Hgt(ft-agl/msl) 4990 5080
Transport Wnd (mph) E 14 E 8
Vent Rate (kt-ft) 59880 35560
Dispersion 5 5
DSI 5 6 4 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ019-160800-
Eastern Interior-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Pcldy
Precip Type Tstms Tstms Showers Showers
Chance Precip (%) 60 50 10 20
Temp (24h trend) 72 (-5) 89 (+1) 73 90
RH % (24h trend) 100 (+7) 63 (-3) 98 59
Wind 20ft/early(mph) E 18 E 17 E 14 E 14
Wind 20ft/late(mph) E 17 E 14 E 14 E 12
Mixing Hgt(ft-agl/msl) 5210 5530
Transport Wnd (mph) E 18 E 16
Vent Rate (kt-ft) 83360 77420
Dispersion 5 5
DSI 5 6 4 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ022-160800-
Luquillo Mountain Range-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Mcldy Pcldy Mclear Pcldy
Precip Type Tstms Tstms Showers Showers
Chance Precip (%) 60 50 20 20
Temp (24h trend) 70 (-4) 85 (+3) 71 86
RH % (24h trend) 100 (+4) 68 (-7) 100 66
Wind 20ft/early(mph) E 16 E 13 E 12 E 12
Wind 20ft/late(mph) E 13 E 13 E 12 E 12
Mixing Hgt(ft-agl/msl) 4620 4770
Transport Wnd (mph) E 20 E 17
Vent Rate (kt-ft) 78540 71550
Dispersion 5 5
DSI 6 6 5 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ023-160800-
Central Mountain Range-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Mclear Pcldy Mclear Pcldy
Precip Type Showers Tstms Showers Tstms
Chance Precip (%) 30 50 10 40
Temp (24h trend) 70 (-3) 87 (+3) 68 88
RH % (24h trend) 100 (+4) 67 (0) 100 61
Wind 20ft/early(mph) NE 21 E 13 E 11 E 10
Wind 20ft/late(mph) E 14 E 13 E 10 E 10
Mixing Hgt(ft-agl/msl) 7310 6990
Transport Wnd (mph) E 13 E 7
Vent Rate (kt-ft) 80410 41940
Dispersion 5 5
DSI 3 6 2 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ024-160800-
Cayey Mountain Range-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Pcldy Mclear Mclear
Precip Type Tstms Showers Showers Showers
Chance Precip (%) 60 40 10 10
Temp (24h trend) 71 (-3) 85 (+1) 70 86
RH % (24h trend) 100 (+4) 69 (+1) 99 64
Wind 20ft/early(mph) E 14 E 13 E 12 E 11
Wind 20ft/late(mph) E 12 E 13 E 11 E 12
Mixing Hgt(ft-agl/msl) 4700 4870
Transport Wnd (mph) E 21 E 18
Vent Rate (kt-ft) 84600 77920
Dispersion 5 5
DSI 6 6 3 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ025-160800-
Vieques-
330 PM AST Sat Aug 15 2026
...RED FLAG WARNING IN EFFECT UNTIL 5 PM AST THIS AFTERNOON...
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Mclear Mclear Pcldy
Precip Type Tstms Showers Showers Showers
Chance Precip (%) 60 40 20 20
Temp (24h trend) 78 (-3) 89 (-1) 80 91
RH % (24h trend) 90 (+8) 59 (-3) 83 56
Wind 20ft/early(mph) E 20 E 19 E 18 E 17
Wind 20ft/late(mph) E 20 E 17 E 18 E 13
Mixing Hgt(ft-agl/msl) 4090 4080
Transport Wnd (mph) E 21 E 20
Vent Rate (kt-ft) 73620 69360
Dispersion 5 5
DSI 6 6 6 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ026-160800-
Culebra-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Mclear Mclear Mclear
Precip Type Tstms Showers Showers Showers
Chance Precip (%) 60 30 20 20
Temp (24h trend) 78 (-3) 89 (0) 79 91
RH % (24h trend) 93 (+8) 63 (-6) 86 58
Wind 20ft/early(mph) E 20 E 19 E 18 E 18
Wind 20ft/late(mph) E 20 E 17 E 17 E 12
Mixing Hgt(ft-agl/msl) 4140 3910
Transport Wnd (mph) E 21 E 21
Vent Rate (kt-ft) 74520 70380
Dispersion 5 5
DSI 6 6 6 6
RH Recovery Excellent Excellent
Remarks...None.
$$
PRZ027-160800-
Southwest Coastal Plains and Mona Island-
330 PM AST Sat Aug 15 2026
...RED FLAG WARNING IN EFFECT UNTIL 5 PM AST THIS AFTERNOON...
Tonight Sun Sun Night Mon
Cloud Cover Mclear Pcldy Mclear Mclear
Precip Type Showers Showers Showers Showers
Chance Precip (%) 10 30 10 10
Temp (24h trend) 75 (-2) 89 (-3) 74 94
RH % (24h trend) 91 (+6) 60 (+5) 93 52
Wind 20ft/early(mph) E 21 E 18 G28 E 16 G23 E 18
Wind 20ft/late(mph) E 17 E 23 G34 E 14 SE 19
Mixing Hgt(ft-agl/msl) 5070 4950
Transport Wnd (mph) E 18 E 17
Vent Rate (kt-ft) 81120 74250
Dispersion 5 5
DSI 5 6 5 6
RH Recovery Excellent Excellent
Remarks...None.
$$
VIZ001-160800-
Saint Thomas and Saint John-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Mclear Mclear Mclear
Precip Type Tstms Showers Showers Showers
Chance Precip (%) 60 30 20 20
Temp (24h trend) 77 (-4) 88 (+1) 77 89
RH % (24h trend) 92 (+7) 60 (-8) 88 58
Wind 20ft/early(mph) E 21 E 19 E 17 E 18
Wind 20ft/late(mph) E 21 E 17 E 17 E 12
Mixing Hgt(ft-agl/msl) 4190 3640
Transport Wnd (mph) E 21 E 22
Vent Rate (kt-ft) 75420 69160
Dispersion 5 5
DSI 6 6 6 6
RH Recovery Excellent Excellent
Remarks...None.
$$
VIZ002-160800-
St Croix-
330 PM AST Sat Aug 15 2026
Tonight Sun Sun Night Mon
Cloud Cover Pcldy Mclear Mclear Clear
Precip Type Tstms Showers Showers None
Chance Precip (%) 60 50 20 0
Temp (24h trend) 78 (-3) 89 (+1) 78 90
RH % (24h trend) 96 (+8) 63 (-6) 88 61
Wind 20ft/early(mph) E 21 E 19 E 17 E 18
Wind 20ft/late(mph) E 20 E 18 E 17 E 13
Mixing Hgt(ft-agl/msl) 4590 4960
Transport Wnd (mph) E 24 E 18
Vent Rate (kt-ft) 96390 79360
Dispersion 5 5
DSI 6 6 6 6
RH Recovery Excellent Excellent
Remarks...None.
$$