Issued by: National Weather Service San Juan, PR
Updated: 2:28 pm AST May 1, 2026
| This Afternoon | Scattered showers. Mostly sunny, with a high near 89. East northeast wind around 10 mph. Chance of precipitation is 40%. |
| Tonight | Isolated showers before 9pm, then isolated showers after 3am. Mostly clear, with a low around 75. East southeast wind 7 to 9 mph. Chance of precipitation is 20%. |
| Saturday | Scattered showers before noon, then isolated showers after 3pm. Mostly sunny, with a high near 89. East wind 9 to 16 mph, with gusts as high as 21 mph. Chance of precipitation is 40%. |
| Saturday Night | Isolated showers after midnight. Mostly clear, with a low around 75. East southeast wind 7 to 9 mph. Chance of precipitation is 10%. |
| Sunday | Isolated showers. Mostly sunny, with a high near 90. East wind 10 to 15 mph. Chance of precipitation is 20%. |
| Sunday Night | Isolated showers. Partly cloudy, with a low around 75. East wind around 9 mph. Chance of precipitation is 10%. |
| Monday | Mostly sunny, with a high near 90. East southeast wind 9 to 16 mph, with gusts as high as 21 mph. |
| Monday Night | Clear, with a low around 76. East southeast wind 6 to 9 mph. |
| Tuesday | Mostly sunny, with a high near 90. East southeast wind 8 to 14 mph. |
| Tuesday Night | Mostly clear, with a low around 75. |
| Wednesday | Mostly sunny, with a high near 90. |
| Wednesday Night | Mostly clear, with a low around 75. |
| Thursday | Scattered showers. Mostly sunny, with a high near 89. Chance of precipitation is 40%. |
368 FXCA62 TJSJ 011651 AFDSJU Area Forecast Discussion National Weather Service San Juan PR 1251 PM AST Fri May 1 2026 ...New SHORT TERM, LONG TERM, AVIATION, MARINE, BEACH FORECAST... .KEY MESSAGES... Updated at 1250 PM AST Fri May 1 2026 * The flood threat will remain elevated across the mountain ranges and western sections of PR through this afternoon. * Across the U.S. Virgin Islands, passing showers expected through the evening hours, and a drying trend during the weekend. * Fair weather conditions expected in general through the middle of next week. Locally induced showers still expected over NW PR. * Warmer-than-normal temperatures will continue through the weekend, with heat indices reaching or exceeding 100F across urban and coastal areas. && .Short Term(This evening through Sunday)... Issued at 1250 PM AST Fri May 1 2026 Variably cloudy skies were observed across the U.S. Virgin Islands today, while mostly sunny to partly cloudy skies prevailed across Puerto Rico. Locally induced low-level clouds and showers were developing around noon over el Yunque area and downwind from the U.S. Virgin Islands. For the rest of this afternoon, showers with isolated thunderstorms are still expected to develop along the Cordillera and western PR, where urban and small stream flooding is expected with the heaviest showers. High temperatures were from the upper-80s to low 90s across the lower elevations of the islands to the upper 70s and mid-80s across the higher elevations. Winds were from the east-southeast up to 10 mph with higher gusts at times and sea breeze variations across the northern and western coasts of PR. A drying trend is expected on Saturday and Sunday. The precipitable water content is expected to drop from 1.70 inches today to near 1.30 inches by Sunday afternoon. This is in response to a building mid-to upper-level ridge from the west, bringing drier air and more stable conditions in general across the northeastern Caribbean. However, locally induced afternoon showers are expected to develop over northwestern PR each afternoon. Additionally, warm to hot conditions will persist, especially across coastal and urban areas, where daily highs will reach the upper 80s to low 90s, with heat indices exceeding 100F. Therefore, stay hydrated if outdoors, and take frequent breaks in shaded or air-conditioned areas to mitigate the risk of heat-related illness. && .Long Term(Monday through next Thursday)... Issued at 159 AM AST Fri May 1 2026 The long-term period will be mainly dominated by generally tranquil, near-seasonal conditions across both Puerto Rico and the U.S. Virgin Islands. Surface high pressure over the central Atlantic will promote east to southeast winds at 8 to 15 mph throughout the period. Aloft, a ridging pattern will persist through Wednesday, supporting stable conditions. As mentioned in previous discussions, the driest period is expected from Monday through Wednesday. A drying trend will lead to improving conditions. Model guidance has been somewhat variable over the past few days, previously indicating below-normal moisture content and now suggesting near-normal values. Nevertheless, PWAT values are expected to remain lower, around 1.5 inches or less. Combined with a mid to upper-level ridge, this will enhance atmospheric stability. Afternoon showers may still develop due to local effects and diurnal heating; however, coverage will be limited and activity brief. Rain chances will range from 10 to 40 percent each afternoon across northwestern Puerto Rico. By Thursday, moisture will increase back to near-normal levels as patches of moisture move into the region. At the same time, an upper- level trough will begin to amplify, briefly increasing instability and the potential for shower development. However, the latest GFS and ECMWF runs indicate that the trough will quickly move away, allowing ridging to reestablish itself in the mid to upper levels as early as Friday. At 925 mb, temperature guidance continues to indicate above-normal values (around the 75th percentile) for this time of year. Combined with a prevailing east to southeasterly wind flow, warm conditions will persist throughout the forecast period. Daytime highs will range from the upper 80s to low 90s in coastal and urban areas, and from the upper 70s to mid-80s in higher elevations. Heat indices will reach the upper 90s to low 100s degrees F each day. A limited heat threat will persist across urban, coastal, and low-elevation areas. Residents and visitors should stay hydrated and limit prolonged sun exposure during peak heating hours. As a result, generally sunny and warm days will prevail, with some light, wind-driven showers overnight and during the early morning hours in windward areas, along with limited afternoon convection across northwestern Puerto Rico. Thursday will have the best chances for rainfall, but overall, minimal impacts are expected. && .AVIATION... (18Z TAFS) Issued at 1250 PM AST Fri May 1 2026 Mainly VFR conditions are expected to prevail across all terminals. However, locally induced SHRA/TSRA over central PR should cause mostly -RA/VCTS across the PR terminals thru at least 01/22z. The 01/12z TJSJ sounding indicated ESE winds up to 6 kt blo FL030. && .MARINE... Issued at 1250 PM AST Fri May 1 2026 A weak surface high pressure will build northeast of the region, over the central Atlantic, through the weekend. Meanwhile, low pressure areas with associated frontal systems will move mainly across the western and north of the high pressure through next week. This pattern will promote mainly light to moderate east to southeast trades across the local waters during the next several days. Seas will generally range between 3 and 5 feet, and occasionally up to 6 feet, driven by a combination of local wind waves and a small, long-period northerly swell. && .BEACH FORECAST... Issued at 1250 PM AST Fri May 1 2026 A moderate risk of rip currents will persist across the north and eastern beaches of the islands. A small, long-period northeasterly swell could promote locally higher breakers at times, and occasionally stronger rip currents are possible along the north- facing beaches of Puerto Rico through the weekend. Beachgoers should exercise caution through the weekend across these areas. For additional information, visit weather.gov/beach/sju. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...None. VI...None. AM...None. && $$ SHORT TERM...DS LONG TERM....YZR AVIATION...DS
