Routine Fire Wx Fcst (With/Without 6-10 Day Outlook)
Issued by NWS San Juan, PR

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586
FNCA52 TJSJ 310909
FWFSJU

Fire Weather Planning Forecast for Puerto Rico
National Weather Service San Juan PR
509 AM AST Sun Aug 31 2025

.DISCUSSION...

The fire weather threat will be low to moderate today. Wind
speeds are expected to, in general, remain close to threshold
values. RH values will generally around threshold values, although
previous rainfall and today`s forecasted PM showers can provide
relief. KBDI values are at 588 in Cabo Rojo, 541 in Guanica, and
727 at St. Croix. Conditions will continue to be monitored closely
throughout the day for any changes.

PRZ014-010915-
Southeast Coastal Plains-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     30           50           40
Temp (24h trend)      92 (+1)      74 (-1)      91
RH % (24h trend)      49 (-8)      88 (-2)      52
Wind 20ft/early(mph)  SE 14 G20    E 10         SE 11
Wind 20ft/late(mph)   SE 14 G20    E 10         SE 11
Mixing Hgt(ft-agl/msl)4300                      4730
Transport Wnd (mph)   E 12                      SE 12
Vent Rate (kt-ft)     43000                     47300
Dispersion            5                         5
DSI                   5            2            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ015-010915-
Southern Hills-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     50           30           30
Temp (24h trend)      89 (+3)      71 (-1)      89
RH % (24h trend)      59 (-8)      99 (+4)      62
Wind 20ft/early(mph)  SE 11        E  8         SE 10
Wind 20ft/late(mph)   SE 11        E  8         SE 10
Mixing Hgt(ft-agl/msl)4960                      5340
Transport Wnd (mph)   E 12                      SE 10
Vent Rate (kt-ft)     49600                     48060
Dispersion            5                         5
DSI                   5            2            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ016-010915-
North Coastal Plains-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Tstms        Showers      Tstms
Chance Precip (%)     40           50           40
Temp (24h trend)      91 (+1)      74 (-1)      92
RH % (24h trend)      60 (-7)      98 (+1)      61
Wind 20ft/early(mph)  E 16         E 13         E 14 G17
Wind 20ft/late(mph)   E 16         E 13         E 14 G17
Mixing Hgt(ft-agl/msl)4590                      4970
Transport Wnd (mph)   E 12                      E 10
Vent Rate (kt-ft)     45900                     44730
Dispersion            5                         5
DSI                   6            4            6
RH Recovery                        Excellent

Remarks...None.

$$

PRZ017-010915-
Northern Hills-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Tstms        Tstms        Tstms
Chance Precip (%)     70           50           50
Temp (24h trend)      89 (+1)      72 (0)       89
RH % (24h trend)      63 (-4)      99 (-1)      63
Wind 20ft/early(mph)  E 12         E 10         E 11
Wind 20ft/late(mph)   E 12         E 10         E 11
Mixing Hgt(ft-agl/msl)5110                      5240
Transport Wnd (mph)   SE  9                     E  8
Vent Rate (kt-ft)     40880                     36680
Dispersion            5                         5
DSI                   5            2            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ018-010915-
West Coast-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Tstms        Showers      Tstms
Chance Precip (%)     60           40           50
Temp (24h trend)      92 (+1)      73 (0)       92
RH % (24h trend)      60 (-6)      98 (0)       61
Wind 20ft/early(mph)  E 11         E 11         E 12
Wind 20ft/late(mph)   E 11         E 11         E 12
Mixing Hgt(ft-agl/msl)4480                      4580
Transport Wnd (mph)   SE  8                     SE  9
Vent Rate (kt-ft)     31360                     36640
Dispersion            5                         5
DSI                   5            3            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ019-010915-
Eastern Interior-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     30           50           50
Temp (24h trend)      90 (+2)      72 (-1)      90
RH % (24h trend)      59 (-5)      99 (+1)      60
Wind 20ft/early(mph)  SE 11        E  9         SE 11
Wind 20ft/late(mph)   SE 11        E  9         SE 11
Mixing Hgt(ft-agl/msl)5260                      6170
Transport Wnd (mph)   SE 10                     SE 12
Vent Rate (kt-ft)     47340                     61700
Dispersion            5                         5
DSI                   5            2            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ022-010915-
Luquillo Mountain Range-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Tstms
Chance Precip (%)     50           60           50
Temp (24h trend)      86 (+4)      68 (-3)      86
RH % (24h trend)      64 (-8)      100 (0)      67
Wind 20ft/early(mph)  SE 10        E  6         SE 10
Wind 20ft/late(mph)   SE 10        E  6         SE 10
Mixing Hgt(ft-agl/msl)4680                      4730
Transport Wnd (mph)   SE 10                     SE 12
Vent Rate (kt-ft)     42120                     47300
Dispersion            5                         5
DSI                   5            3            6
RH Recovery                        Excellent

Remarks...None.

$$

PRZ023-010915-
Central Mountain Range-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Tstms        Showers      Tstms
Chance Precip (%)     80           30           50
Temp (24h trend)      87 (+4)      69 (-1)      87
RH % (24h trend)      64 (-8)      99 (0)       65
Wind 20ft/early(mph)  SE  8        E  8         SE  8
Wind 20ft/late(mph)   SE  8        E  8         SE  8
Mixing Hgt(ft-agl/msl)5520                      5770
Transport Wnd (mph)   SE  8                     SE  8
Vent Rate (kt-ft)     38640                     40390
Dispersion            5                         5
DSI                   5            1            5
RH Recovery                        Excellent

Remarks...None.

$$

PRZ024-010915-
Cayey Mountain Range-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     30           60           50
Temp (24h trend)      86 (+2)      70 (0)       86
RH % (24h trend)      61 (-5)      100 (0)      63
Wind 20ft/early(mph)  SE 10        E  6         SE  9
Wind 20ft/late(mph)   SE 10        E  6         SE  9
Mixing Hgt(ft-agl/msl)4780                      5380
Transport Wnd (mph)   E 10                      SE 10
Vent Rate (kt-ft)     43020                     48420
Dispersion            5                         5
DSI                   5            2            6
RH Recovery                        Excellent

Remarks...None.

$$

PRZ025-010915-
Vieques-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     40           50           50
Temp (24h trend)      90 (+1)      76 (0)       91
RH % (24h trend)      57 (-13)     97 (+3)      58
Wind 20ft/early(mph)  E 11         E 11         E 11
Wind 20ft/late(mph)   E 11         E 11         E 11
Mixing Hgt(ft-agl/msl)3400                      3250
Transport Wnd (mph)   E 13                      SE 12
Vent Rate (kt-ft)     37400                     32500
Dispersion            5                         5
DSI                   6            6            6
RH Recovery                        Excellent

Remarks...None.

$$

PRZ026-010915-
Culebra-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     30           40           40
Temp (24h trend)      92 (+2)      75 (-3)      92
RH % (24h trend)      57 (-14)     100 (+6)     59
Wind 20ft/early(mph)  E 11         E 11         E 11
Wind 20ft/late(mph)   E 11         E 11         E 11
Mixing Hgt(ft-agl/msl)3420                      3370
Transport Wnd (mph)   E 14                      SE 13
Vent Rate (kt-ft)     41040                     37070
Dispersion            5                         5
DSI                   6            6            6
RH Recovery                        Excellent

Remarks...None.

$$

PRZ027-010915-
Southwest Coastal Plains and Mona Island-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Mclear       Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     30           10           30
Temp (24h trend)      93 (+2)      75 (-1)      93
RH % (24h trend)      52 (-5)      90 (+2)      52
Wind 20ft/early(mph)  SE 16 G21    E 11         SE 16 G21
Wind 20ft/late(mph)   SE 16 G21    E 11         SE 16 G21
Mixing Hgt(ft-agl/msl)4810                      4560
Transport Wnd (mph)   E 15                      SE 15
Vent Rate (kt-ft)     62530                     59280
Dispersion            5                         5
DSI                   5            3            6
RH Recovery                        Excellent

Remarks...None.

$$

VIZ001-010915-
Saint Thomas and Saint John-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Pcldy        Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     20           40           40
Temp (24h trend)      89 (+2)      75 (-3)      89
RH % (24h trend)      63 (-11)     98 (+5)      65
Wind 20ft/early(mph)  E 11         E 11         E 11
Wind 20ft/late(mph)   E 11         E 11         E 11
Mixing Hgt(ft-agl/msl)3400                      3360
Transport Wnd (mph)   E 15                      SE 14
Vent Rate (kt-ft)     44200                     40320
Dispersion            5                         5
DSI                   6            6            6
RH Recovery                        Excellent

Remarks...None.

$$

VIZ002-010915-
St Croix-
509 AM AST Sun Aug 31 2025

                      Today        Tonight      Mon

Cloud Cover           Mclear       Pcldy        Pcldy
Precip Type           Showers      Showers      Showers
Chance Precip (%)     20           40           40
Temp (24h trend)      90 (+2)      77 (-2)      90
RH % (24h trend)      61 (-10)     95 (+6)      63
Wind 20ft/early(mph)  E 11         E 11         E 11
Wind 20ft/late(mph)   E 11         E 11         E 11
Mixing Hgt(ft-agl/msl)4410                      4720
Transport Wnd (mph)   E 14                      E 14
Vent Rate (kt-ft)     52920                     56640
Dispersion            5                         5
DSI                   6            6            6
RH Recovery                        Excellent

Remarks...None.

$$


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