Weather & sea

Official alerts, rain windows, UV, tides, sea state, STT observations and the tropical outlook — every figure with its source and last-polled time.

St. John right nowpartial

82°F

Clear sky · feels like 87°

Rain chance0%

Wind9mphfrom E

Humidity71%

UV index2Low

Good window for a beach morningLower wind and manageable early-day sun favor a calm start outdoors.

Open-Meteo · polled 5:34 PM AST · fresh

Next 12 hours

Temperature line · rain-chance bars

5 PM10ESE

6 PM10ESE

7 PM12E

8 PM12E

9 PM12E

10 PM13E

11 PM13E

12 AM13E

1 AM13E

2 AM13E

3 AM13E

4 AM13E

Wind, mph, and the direction it blows from.

NOAA / National Weather Service hourly forecast · polled 5:18 PM AST · fresh

Notable rain windowsConsecutive NWS hours at or above 40%.

Sun 12 AM–3 AM ASTScattered Rain Showers
50%

Next 7 days

Tap a day for UV, wind and daylight

Today50%78°88°

Isolated Rain Showers / Scattered Rain Showers

UV max model: 8.6 · Very high
Wind NWS: E 13 mph
Gusts model: 18 mph
Daylight model: 6:08 AM – 6:11 PM
High / low source: NWS / NWS

Sun 2740%77°88°

Scattered Rain Showers

UV max model: 8.5 · Very high
Wind NWS: E 16 mph
Gusts model: 20 mph
Daylight model: 6:08 AM – 6:10 PM
High / low source: NWS / NWS

Mon 2830%76°88°

Isolated Rain Showers / Scattered Rain Showers

UV max model: 8.3 · Very high
Wind NWS: E 14 to 18 mph
Gusts model: 22 mph
Daylight model: 6:09 AM – 6:10 PM
High / low source: NWS / NWS

Tue 2920%76°87°

Isolated Rain Showers

UV max model: 8.5 · Very high
Wind NWS: ENE 20 mph
Gusts model: 23 mph
Daylight model: 6:09 AM – 6:09 PM
High / low source: NWS / NWS

Wed 3030%75°85°

Isolated Rain Showers / Scattered Rain Showers

UV max model: 8.4 · Very high
Wind NWS: E 20 mph
Gusts model: 26 mph
Daylight model: 6:09 AM – 6:08 PM
High / low source: NWS / NWS

Thu 120%75°86°

Isolated Rain Showers

UV max model: 8.4 · Very high
Wind NWS: E 16 mph
Gusts model: 29 mph
Daylight model: 6:09 AM – 6:07 PM
High / low source: NWS / NWS

Fri 230%75°87°

Scattered Rain Showers

UV max model: 8.3 · Very high
Wind NWS: E 15 mph
Gusts model: 24 mph
Daylight model: 6:09 AM – 6:06 PM
High / low source: NWS / NWS

Fresh NWS high, low, rain and wind values replace the matching model field; UV, gusts and daylight remain Open-Meteo model guidance. NOAA / National Weather Service · polled 5:21 PM AST · fresh · Open-Meteo · polled 5:34 PM AST · fresh. Official alerts still take priority.

What NWS San Juan expects

This AfternoonSat 5:00 PM AST

88°

Isolated Rain Showers

Rain: 20%
Wind: ESE 10 mph

TonightSat 6:00 PM AST

78°

Scattered Rain Showers

Rain: 50%
Wind: E 13 mph

SundaySun 6:00 AM AST

88°

Scattered Rain Showers

Rain: 30%
Wind: E 15 mph

Sunday NightSun 6:00 PM AST

77°

Scattered Rain Showers

Rain: 40%
Wind: E 16 mph

MondayMon 6:00 AM AST

88°

Isolated Rain Showers

Rain: 20%
Wind: E 14 to 18 mph

Monday NightMon 6:00 PM AST

76°

Scattered Rain Showers

Rain: 30%
Wind: E 17 mph

NOAA / National Weather Service · polled 5:21 PM AST · fresh

On island, on the water, and at STT

Sun strength right now

2.2Low

Feels like: 87°F
Gusts: 13 mph
Current precipitation: 0.00 in

Open-Meteo model estimate. Official NWS alerts and forecasts take priority.

Wind on the island

9mph

from E (98°)

Gusting to: 13 mph
Offshore buoy wind: —

Island-wide wind is context, not a beach verdict — exposure and swell direction still decide a bay.

Modeled air quality and dust

59 AQIModerate

PM2.5: 9.2 µg/m³
PM10: 17.2 µg/m³
Surface dust: 7.0 µg/m³
Aerosol optical depth: 0.12

CAMS Global model via Open-Meteo · roughly 45 km resolution · fresh. Not a local monitor or an air-quality all-clear; official advisories take priority.

Lameshur Bay tides

Next: High Sat, Sep 26, 8:19 PM AST

High tideSat, Sep 26, 8:19 PM AST
0.8 ft

NOAA station 9751381 · predicted heights relative to MLLW · fresh.

STT airport weather

VFRVisual flight rules

Temperature: 87°F
Wind: SE (130°) · 9 mph
Gusts: — mph
Visibility: 10+ mi

METAR TIST 262053Z 13008KT 10SM FEW030 31/24 A2992 RMK AO2 SLP131 T03060239 55002 $

Observed Sat, Sep 26, 4:53 PM AST · fresh. METAR is weather context, not flight status.

Sea south of St. John

No fresh buoy observation is available. Stale readings older than six hours are withheld.

Waters around St. John

NWS coastal zone AMZ726

Tonight2–3 ft

East winds 5 to 10 knots. Seas 2 to 3 feet. Wave Detail: East 2 feet at 5 seconds. Isolated showers early this evening, then scattered showers late this evening and overnight.

Sunday2–3 ft

East winds 10 to 15 knots with gusts up to 20 knots. Seas 2 to 3 feet. Wave Detail: East 2 feet at 5 seconds. Scattered showers.

Sunday Night3–4 ft

East winds 10 to 15 knots with gusts up to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at 5 seconds. Scattered showers.

Monday3–4 ft

East winds 10 to 15 knots with gusts up to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at 5 seconds. Scattered showers.

Monday Night3–4 ft

East winds 10 to 15 knots with gusts up to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at 5 seconds. Scattered showers.

Tuesday3–4 ft

East winds 10 to 15 knots with gusts up to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at 5 seconds. Scattered showers.

NWS zone AMZ726 · issued Sat 3:40 PM AST. This broad coastal forecast does not establish conditions inside a particular bay.

Atlantic tropics

National Hurricane Center

Active cyclones

Tropical depression Fay

From St. John: ≈ 1531 mi NE
Max winds: 30 kt (35 mph)
Pressure: 1009 mb
Position: 29.8°N 43.9°W
Moving: S at 2 kt

Updated Sat, Sep 26, 5:00 PM AST

Open NHC advisory ↗

Potential tropical cyclone Gonzalo

From St. John: ≈ 2704 mi E
Max winds: 35 kt (40 mph)
Pressure: 1005 mb
Position: 19.3°N 23.3°W
Moving: NNW at 7 kt

Updated Sat, Sep 26, 5:00 PM AST

Open NHC advisory ↗

Areas being watched

Atlantic basin · areas of disturbed weather2-day formation: 10% (Low) · 7-day: 20% (Low)Issued Sat, Sep 26, 1:40 PM AST

NHC Tropical Weather Outlook ↗

Recent M3+ USGS events

Within 311 miles of St. John

M 3.2

25 miles SE of Esperanza, Puerto Rico

Sat, Sep 26, 11:03 AM AST · 7.3 mi deep · reviewed

USGS ↗

M 3.0

35 miles ENE of Punta Cana, Dominican Republic

Thu, Sep 24, 1:57 PM AST · 12.5 mi deep · reviewed

USGS ↗

M 3.7

29 miles SE of Boca de Yuma, Dominican Republic

Wed, Sep 23, 8:07 PM AST · 54.1 mi deep · reviewed

USGS ↗

M 3.2

40 miles SE of Punta Cana, Dominican Republic

Wed, Sep 23, 8:37 AM AST · 26.4 mi deep · reviewed

USGS ↗

M 3.3

83 miles NNE of Vieques, Puerto Rico

Tue, Sep 22, 3:18 PM AST · 7.7 mi deep · reviewed

USGS ↗

How to read this page

UV and heat

Tropical sun can become the limiting condition even on a beautiful day. Shift exposed activity earlier and treat shade and water as part of the plan.

Wind and water

Island-wide wind is context, not a beach verdict. Exposure, swell direction, local terrain and operator guidance still decide whether water activity is appropriate.

Rain and alerts

A model forecast is guidance. An NWS watch or warning is official safety information and always takes priority over platform suggestions.

What this page currently knows

Data policy

Regional earthquakesU.S. Geological Survey · officialfresh
St. John model weatherOpen-Meteo · authoritativefresh
Atlantic tropical weather outlookNOAA National Hurricane Center · officialfresh
Official weather alertsNOAA / National Weather Service · officialfresh
Official St. John marine alertsNOAA / National Weather Service · officialfresh
St. John power outagesVirgin Islands Water and Power Authority · authoritativefresh
Atlantic tropical cyclonesNOAA National Hurricane Center · officialfresh
STT airport observationsNOAA Aviation Weather Center · officialfresh
Official St. John forecastNOAA / National Weather Service · officialfresh
Atlantic tropical weather outlook textNOAA National Hurricane Center · officialfresh
Official St. John hourly forecastNOAA / National Weather Service · officialfresh
St. John coastal waters forecastNOAA / National Weather Service · officialfresh
St. John modeled air qualityOpen-Meteo / CAMS Global · authoritativefresh
Lameshur Bay tide predictionsNOAA Tides & Currents · officialfresh
USVI sargassum updateVirgin Islands DPNR · officialfresh
Virgin Islands National Park eventsU.S. National Park Service · officialfresh
USVI beach water-quality bulletinVirgin Islands DPNR · officialfresh
St. John beach sample historyEPA Water Quality Portal · officialfresh
Sea conditions south of St. JohnNOAA NDBC / CariCOOS · officialstale
Virgin Islands National Park operationsU.S. National Park Service · officialstale