
Northern US Virgin Islands and Culebra Marine Forecast
Rest Of Today...West Winds 5 To 10 Knots. Seas 2 To 4 Feet With Occasional Seas Around 5 Feet. Dominant Period 11 Seconds. Isolated Showers. |
Tonight...West Winds 10 To 15 Knots. Seas 3 To 5 Feet With Occasional Seas Up To 6 Feet. Dominant Period 10 Seconds. |
Thursday...Northwest Winds 10 To 15 Knots. Seas 3 To 5 Feet With Occasional Seas Up To 6 Feet. Dominant Period 11 Seconds. Numerous Showers. |
Thursday Night...North Winds 10 To 15 Knots. Seas 6 To 8 Feet With Occasional Seas Up To 10 Feet. Dominant Period 12 Seconds. Scattered Showers. |
Friday...North Winds 10 To 15 Knots. Seas 6 To 8 Feet With Occasional Seas Up To 10 Feet. Dominant Period 11 Seconds. Isolated Showers. |
Saturday...Southeast Winds 5 To 10 Knots. Seas 6 To 8 Feet With Occasional Seas Up To 10 Feet. Dominant Period 12 Seconds. Isolated Showers. |
Sunday...South Winds 5 To 10 Knots, Becoming East. Seas 6 To 8 Feet With Occasional Seas Up To 10 Feet. Dominant Period 14 Seconds. |
Area Forecast Discussion ...CORRECTED National Weather Service San Juan PR 516pm AST Monday Feb 17 2025 Synopsis Stable weather conditions will prevail for the most part with patches of moisture streaming across the area from time to time. Breezy conditions will persist through most of the period, particularly across coastal areas of the islands. Wind-driven seas will subside tonight, returning once again by midweek. .SHORT TERM... Tonight through Wednesday... A stable weather pattern prevailed across the region, with mostly clear skies in the early morning. By early afternoon, some cloudiness developed over the mountains, particularly in the Cordillera Central, and moved northwestward into northern Puerto Rico. Winds remained east-southeast at 10-15 mph, with gusty conditions along coastal areas. Daytime temperatures ranged from the lower to upper 80s across most of the CWA. Satellite imagery indicates a predominant area of dry air in the region; however, an area of precipitable water (PWAT) of 1.1 inches is expected to continue moving in tonight. This increase in cloud cover and humidity could lead to more passing showers across eastern Puerto Rico and the U.S. Virgin Islands.On Tuesday, southeasterly winds will persist due to the influence of surface high pressure over the central Atlantic. Embedded within this flow, a patch of moisture will increase relative humidity at 850-500 MB near climatological normals. This setup will enhance showers across windward coastal areas of the islands. However, shower activity is expected to remain localized, with rainfall accumulations generally below one inch. As the week progresses, the surface high pressure will evolve as it interacts with a frontal boundary far north of the region. This will cause winds to shift back to the east-northeast by late Tuesday into Wednesday, pushing patches of low-level trapped moisture across the region and inducing a showery weather pattern with light to moderate showers over windward coastal areas of the islands. Long Term Thursday through Monday... /issued 441am AST Monday Feb 17 2025/ Global models suggest weakening of the broad ridge over the central Atlantic throughout the long term period, as back to back upper level troughs with associated fronts move across the western Atlantic. The frontal boundaries are expected to remain just north of the region, however, pre-frontal troughs are expected to develop over the islands and bring increasing moisture content from late in the workweek and through the weekend. The GFS indicates peaks of just over 1.50 inches of PWAT (Precipitable Water) during this period, while the ECMWF (European Centre for Medium-Range Weather Forecasts) suggest slightly higher moisture content with a shearline moving over or close to the area on Sunday. Consequently, the likelihood of showers and periods of locally heavy rainfall will increase if this weather pattern unfolds. A weak surface ridge over the central and eastern Atlantic will promote light to moderate trades until late in forecast cycle, when a broad surface high builds over the western Atlantic promoting moderate to locally fresh east to northeast winds. Seasonal temperatures will persist, with daytime highs reaching the mid-80s across the U.S. Virgin Islands and the north/eastern sections of Puerto Rico. In contrast, the southern to western coast of Puerto Rico may experience temperatures ranging from the mid-80s to low 90s. Minimum temperatures are generally expected to range from the low to mid-70s in coastal areas to the upper 50s and low 60s in higher elevations. Marine Choppy to hazardous seas will continue through at least early in the workweek across most offshore waters and Anegada Passage. Moderate to locally fresh east to southeasterly winds will continue tonight, turning more east to northeast from Tuesday onwards. A surface trough moving from the east will increase shower activity by the end of the workweek. Beach Forecast Northern nearshore buoys were estimating breaking waves of 6-9 feet. Weak pulses of a northerly swell are expected to continue for the rest of the afternoon through late tonight. Therefore, a high rip current risk was issued for north-oriented beaches of Puerto Rico, from Aguadilla to Fajardo, as well as the beaches of Culebra and northern U.S. Virgin Islands. Elsewhere, expect moderate risk of rip currents. Fire Weather /issued 441am AST Monday Feb 17 2025/ Another drier air mass is expected to move during the day over the islands and relative humidities could drop once again below 55% across the southern hills and coastal sections of Puerto Rico, particularly from Santa Isabel to Lajas. The combination of southeasterly winds with the sea breeze is expected to bring sustained wind speeds above 15 mph with gusts over 25 mph across the same areas, and KBDI values remain at Red Flag criteria in Guanica (604). Given the expected conditions, a Fire Danger Statement has been issued due to the elevated risk of fire spread. .SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk through late tonight for PRZ001-002-005- 008-012. VI...High Rip Current Risk through late tonight for VIZ001. AM...Small Craft Advisory until 6am AST Tuesday for AMZ711-723. |