Anegada Passage Southward to 17N Marine Forecast
| Rest Of Today...Southwest 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 5 To 10 Knots. Seas 2 To 4 Feet With Occasional Seas Around 5 Feet. Dominant Period 11 Seconds. Isolated Showers. |
| Thursday...West Winds 10 To 15 Knots. Seas 3 To 5 Feet With Occasional Seas Up To 6 Feet. Dominant Period 12 Seconds. Isolated 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, Becoming Northeast. Seas 5 To 7 Feet With Occasional Seas Up To 9 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 5 To 7 Feet With Occasional Seas Up To 9 Feet. Dominant Period 14 Seconds. |
| Area Forecast Discussion National Weather Service San Juan PR 457am AST Sunday May 17 2026 .Short Term(Today through Tuesday)... Issued at 455am AST Sunday May 17 2026 Current satellite derived precipitable water (PWAT) values indicate broad moisture over the islands steered by east to east-southeast winds. PWAT (Precipitable Water) values range from 1.57 to 1.65 inches, at normal values for this time of the year. Showers continue to be steered towards windward areas with at least minimal accumulations detected by midnight over the eastern third of PR, interior PR, Vieques, Culebra, and the USVI. Accumulations above 0.6 inches stayed over the waters. Although t-storms did not develop over the local waters overnight, they did develop just south and west of our local waters. Patchy fog was also detected over sectors of interior PR. Minimum temperatures have been in the mid 70s to around 80 over urban and coastal sectors of the islands, and in the upper 50s to the 60s at higher elevations of PR. East to east-southeast winds will continue to steer broad moisture towards the region today and Tuesday, with more intermittent patches of drier air arriving on Monday. PWAT (Precipitable Water) values will be generally at normal values today and Tuesday, and reaching below normal values at times on Monday. PWAT (Precipitable Water) values can, however, locally reach above normal values during afternoon convection. Moisture steered towards the region today was also part of the moisture field of a tropical wave that already moved south of the region over the Caribbean Sea. An amplifying upper level trough will continue to approach the region from the west today, moving over the area later today and remaining during the period, this can promote increased instability and increase the frequency of showers. The presence of patches of drier air in the mid-levels can help inhibit this activity. Showers will continue to be steered towards windward sectors, resulting in periods of variable to showery weather. This can result in ponding of water over roads and poorly drained areas with a chance of urban and small stream flooding. The upper trough will also aid in the development of afternoon convection, in addition to diurnal heating, local orographic effects and sea breeze convergence. This afternoon convection, showers and isolated t-storms, will develop over interior towards the western half of Puerto Rico, as well as downwind of El Yunque, and the USVI towards eastern PR. This will result in a limited to elevated flooding risk and flood advisories might need to be issued each afternoon. Galvez-Davidson Indices are forecast at up to around 35 today, 30, tomorrow and 25 to 30 on Tuesday. Although rain is expected, above normal temperatures will continue today, as indicated by 925 mb temperature guidance. Highs will reach the upper 80s to lower 90s across urban and coastal areas while heat indices exceed 100 to 105 degrees F during the afternoon hours. This will result in a limited to elevated heat risk. Current guidance suggests more normal 925 mb temperatures tomorrow and Tuesday, prompting a limited heat risk. Low concentrations of saharan dust over the region will continue to sharply decrease today. .Long Term(Wednesday through Sunday)... Issued at 455am AST Sunday May 17 2026 A typical late spring to early summer weather pattern is expected through the long-term period. Broad surface high pressure over the northwestern Atlantic will maintain moderate to fresh east to east- southeasterly winds across the local islands, with occasionally strong winds at times. Winds are expected to strengthen further into next weekend, supporting breezy to locally windy conditions. At mid and upper levels, the area will remain between ridging to the southeast and a lingering trough/low over the western Atlantic, while weak disturbances move around the broader pattern and approach the northeastern Caribbean. This pattern will help support periods of increased instability and more favorable conditions for deeper afternoon convection late in the week and into the holiday weekend. Patchy moisture embedded within the trade winds will continue to promote passing showers during the overnight and morning hours each day, followed by afternoon showers and isolated thunderstorms mainly across interior and western to northwestern areas. Although mid- level conditions may remain somewhat marginal at times, the combination of local effects and strong daytime heating should still support deeper convection each afternoon. Flooding concerns are expected to gradually increase and become more locally elevated late in the week and into the holiday weekend, with locally heavy rainfall, ponding of water on roads, and localized urban and small stream flooding possible. Additional hazards will include lightning, heat, and gusty winds, especially as outdoor activity increases during the Memorial Day weekend. Marine Issued at 455am AST Sunday May 17 2026 A broad surface high pressure over the central Atlantic will promote moderate to locally fresh east to east-southeasterly winds across the regional waters through at least today. From late today into early next week, winds will turn more easterly as another surface high pressure builds over the western Atlantic. These breezy conditions will maintain somewhat choppy seas, particularly across the offshore and exposed Atlantic and Caribbean waters. Seas are expected to range between 4 and 6 feet during the next several days. Afternoon and early evening isolated thunderstorms can be expected each day across the northwestern waters of Puerto Rico. Beach Forecast Issued at 455am AST Sunday May 17 2026 A moderate risk of life-threatening rip currents will prevail across the east, north, and southern beaches of Puerto Rico and the U.S. Virgin Islands through next week. Beach goers should exercise caution when entering these beaches. This means life-threatening rip currents are possible in the surf zones, and beachgoers should exercise caution when entering these beaches. If you become caught in a rip current, yell for help. Remain calm, do not exhaust yourself and stay afloat while waiting for help. If you have to swim out of a rip current, swim parallel to shore and back toward the beach when possible. Do not attempt to swim directly against a rip current as you will tire quickly. .SJU WATCHES/WARNINGS/ADVISORIES... PR...None. VI...None. AM...None. |
San Juan Radar
Southeast Radar