Mona Passage Southward to 17N Marine Forecast
| Today...Southeast Winds Around 5 Knots, Becoming South Late This Morning And Afternoon. Seas 2 To 3 Feet. Wave Detail: North 3 Feet At 10 Seconds And Southeast 2 Feet At 5 Seconds. Numerous Showers Early This Morning. Isolated Thunderstorms This Morning. Scattered Showers Late This Morning And Afternoon. |
| Tonight...Southeast Winds 5 To 10 Knots. Seas 2 To 3 Feet. Wave Detail: Southeast 2 Feet At 5 Seconds And North 2 Feet At 10 Seconds. |
| Monday...Southeast Winds 5 To 10 Knots. Seas 2 To 3 Feet. Wave Detail: East 2 Feet At 5 Seconds And North 2 Feet At 9 Seconds. Numerous Showers. |
| Monday Night...East Winds 5 To 10 Knots. Seas 3 To 4 Feet, Occasionally To 5 Feet. Wave Detail: Southeast 3 Feet At 6 Seconds And Northeast 2 Feet At 14 Seconds. Scattered Showers. |
| Tuesday...East Winds 5 To 10 Knots. Seas 3 To 4 Feet, Occasionally To 5 Feet. Wave Detail: Southeast 3 Feet At 6 Seconds And North 2 Feet At 14 Seconds. Scattered Showers. |
| Tuesday Night...East Winds 10 To 15 Knots With Gusts Up To 20 Knots. Seas 3 To 4 Feet, Occasionally To 5 Feet. Wave Detail: Southeast 3 Feet At 6 Seconds And North 2 Feet At 12 Seconds. Scattered Showers. |
| Wednesday...East Winds 10 To 15 Knots, Diminishing To 5 To 10 Knots In The Afternoon. Seas Around 3 Feet. Scattered Showers In The Morning. |
| Wednesday Night...East Winds 5 To 10 Knots, Increasing To 10 To 15 Knots After Midnight. Seas Around 3 Feet. Scattered Showers. |
| Thursday...East Winds 10 To 15 Knots. Seas 3 To 4 Feet, Occasionally To 5 Feet. Scattered Showers. |
| Thursday Night...East Winds 10 To 15 Knots. Seas Around 4 Feet, Occasionally To 5 Feet. Winds And Seas Higher In And Near Thunderstorms. |
| Area Forecast Discussion National Weather Service San Juan PR 240pm AST Sunday April 26 2026 .Short Term(This evening through Tuesday)... Issued at 240pm AST Sunday April 26 2026 In general, the US Virgin Islands and Puerto Rico had mostly clear skies and above-normal temperatures, with maximum temperatures reaching the low 90s at coastal sites and heat indices between 98 and 102 degrees Fahrenheit. Some showers moved across St Croix, St Thomas, and St John early in the morning, and some were detected downwind from the islands in the form of streamers early this afternoon. Cloudiness is also increasing across the interior and northern PR at the moment of writing this discussion. The winds were calm to light and variable, influenced by sea breeze variations. Although this afternoon most of the islands will have mostly sunny skies under warmer-than-normal temperatures and heat indices due to the southerly wind flow, showers and isolated thunderstorms will most likely develop across the interior and northern sections of PR late this afternoon into the evening, as well as near the USVI surrounding waters moving inland. Additionally, later this evening, we cannot rule out additional rounds of showers and possible isolated thunderstorms affecting the USVI, and showers in southern windward locations in PR, as moisture from the Caribbean interacts with a mid- to upper-level trough lingering over the Northeast Caribbean. Moisture will continue to increase vertically across the region, interacting with a mid- to upper-level trough lingering over the region, which will promote an unstable wet pattern early this workweek (Monday and Tuesday). The light winds will continue from the south on Monday, becoming more east-southeast on Tuesday. If showers and thunderstorms develop, they will slowly move across the region, potentially increasing the risk of flooding. Please be aware of the potential for flooding rains across the USVI and PR each day. Also, across areas where no rain develops and early in the afternoon before rain activity, a warming trend is likely, mainly due (among other factors) to the southerly wind flow and above- normal sea surface temperatures across the Caribbean waters. Long Term (Wednesday through Sunday)... Issued at 400am AST Sunday April 26 2026 Overall, a moist and unstable weather pattern will persist from Wednesday through Friday across Puerto Rico and the U.S. Virgin Islands. Abundant Caribbean moisture, combined with a mid-to-upper- level trough and an induced surface trough, will support unsettled conditions through late week. A surface high pressure system over the central Atlantic will maintain a light to moderate south- southeasterly wind flow, promoting warm temperatures and high humidity. A gradual drying trend is expected over the weekend, allowing for a slight improvement in weather conditions. From Wednesday through Friday, moisture levels will remain above normal, with precipitable water (PWAT) values generally ranging between 1.75 and 2.00 inches. This will support a pattern of daily showers and isolated thunderstorms, with the most active convection developing during the afternoon across the interior and northern portions of Puerto Rico. Morning activity will favor southern and eastern Puerto Rico as well as the U.S. Virgin Islands, followed by afternoon convection affecting urban and metropolitan areas. By Saturday into Sunday, slightly drier air will begin to filter into the region. Although afternoon showers will still develop, overall coverage and intensity should decrease compared to earlier in the period. Warm conditions will persist throughout the period due to the prevailing south-southeasterly flow. Temperatures at the 925 mb level will remain above normal for this time of the year through at least Friday, gradually easing into the weekend. Maximum surface temperatures will range from the upper 80s to low 90s across coastal and urban areas, and from the low to mid-80s in higher terrains. Combined with high humidity, heat indices are expected to exceed 100°F daily, particularly through Friday. Residents and visitors are encouraged to continue monitoring the forecast, stay well hydrated, take frequent breaks from the heat, and limit prolonged sun exposure, especially during peak afternoon hours. Marine Issued at 240pm AST Sunday April 26 2026 The remnants of an old front north of the region will continue as a surface low enters the northwestern Atlantic. Meanwhile, a surface high pressure over the central Atlantic will continue to weaken, as the surface low strengthens during the next few days. This pattern will promote light to moderate southerly winds through at least Tuesday, when they will turn more ESE by around midweek. Pulses of small, long-period NNE swells will continue to spread across the Atlantic waters and passages through next week. The possibility of showers and thunderstorms will increase from this evening through at least the middle of the week. Beach Forecast Issued at 240pm AST Sunday April 26 2026 The risk of rip currents is low along the southerly facing beaches in PR and the USVI. However, we encourage beach enthusiasts to exercise caution while enjoying the north-facing beaches from Rincon to Fajardo, and the northern shores of Culebra, Vieques, St. Croix, St. Thomas, St. John, and nearby islands, as we occasionally experience northeast swells promoting the formation of life-threatening rip currents as they break at the shore. Stay safe! Keep an eye out for possible afternoon thunderstorms across portions of PR and the USVI, which could bring strong, gusty winds and lightning. .SJU WATCHES/WARNINGS/ADVISORIES... PR...None. VI...None. AM...None. |
San Juan Radar
Southeast Radar