A moist and unstable weather pattern affected Puerto Rico from March 24 through March 28, 2026, as a mid- to upper-level trough interacted with abundant tropical moisture and favorable upper-level dynamics. Periods of heavy showers and thunderstorms developed across the island, resulting in flooding concerns, urban and small-stream flooding, and rapid rises on rivers and streams.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS SJU wrote it up.
A moist and unstable weather pattern affected Puerto Rico from March 24 through March 28, 2026, as a mid- to upper-level trough interacted with abundant tropical moisture and favorable upper-level dynamics. Periods of heavy showers and thunderstorms developed across the island, resulting in flooding concerns, urban and small-stream flooding, and rapid rises on rivers and streams. The threat was enhanced by strong upper-level support associated with a strengthening jet stream and persistent moisture across the region.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Juan, PR wrote its last area forecast discussion before the first event at Mar 24, 2:01 PM AST, 2 hours 49 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service San Juan PR 201 PM AST Tue Mar 24 2026 ...New SHORT TERM, LONG TERM, AVIATION, MARINE, BEACH FORECAST... .KEY MESSAGES... Issued at 148 PM AST Tue Mar 24 2026 * Moderate to heavy showers will continue today across the interior, western and southern Puerto Rico. There is an elevated flooding risk, as well as a localized limited risk of isolated lightning. * A moderate rip current risk is in effect across the north and eastern coasts of Puerto Rico, Culebra, Vieques, and the U.S. Virgin Islands. However, marine conditions are expected to gradually improve, with more favorable seas across the local waters. * Weather conditions are expected to deteriorate from Thursday into the weekend due to the influence of a mid-to-upper level trough. * The latest model guidances continues to suggest the arrival of a northerly swell by early next week, likely to increase breaking waves over northern-facing beaches of Puerto Rico and the U.S. Virgin Islands and result in hazardous conditions for beachgoers. && .Short Term(This evening through Thursday)... Issued at 148 PM AST Tue Mar 24 2026 Light showers were observed across Puerto Rico and the U.S. Virgin Islands throughout the morning, with Doppler radar estimating minimal accumulations. By mid-morning, cloud cover increased over eastern Puerto Rico and along the central mountain range. Around noon, convective activity intensified over Juncos, San Lorenzo, and Caguas, producing moderate to heavy rain. Radar estimates for these areas ranged between 1.50 and 2.00 inches. Rainfall will persist across eastern Puerto Rico through the afternoon. Additionally, showers have begun across southern Puerto Rico and are expected to intensify later today; a few isolated thunderstorms cannot be ruled out. This weather pattern is driven by sufficient low-level moisture from the remnants of a decaying frontal boundary, coupled with instability from a weakening upper- level trough. As a surface high-pressure system settles to the north, winds will shift from the northeast to the east today, eventually becoming east- southeast by Wednesday. Similar conditions will prevail tomorrow as abundant low-level moisture combines with daytime heating and local effects to enhance shower activity across western Puerto Rico. In the U.S. Virgin Islands, occasional passing showers will continue daily during the morning and early afternoon. Weather conditions are expected to deteriorate by Thursday as a tilted mid-to-upper-level trough approaches from the north. This feature will heighten instability and increase moisture content, with Precipitable Water (PWAT) values rising to near 2.00 inches. Colder temperatures aloft will further support convective development. Given this pattern, there is a limited to elevated flooding risk across Puerto Rico. Urban and small-stream flooding is likely during the heaviest rains, particularly in central and western regions. Residents and visitors should monitor the latest forecasts, as the risk of flooding impacts will increase from Thursday onward. && .Long Term(Friday through next Monday)... Issued at 306 AM AST Tue Mar 24 2026 As mentioned previously, Friday is expected to be the wettest day of the period. Moisture is expected to remain elevated on Friday, with precipitable water (PW) values generally in the 1.50 to 1.80 inch range, which is above normal for late March. Increased low-level moisture, along with a weak mid to upper-level trough near the region will support widespread cloudiness and periods of showers. Temperatures near 500 mb are forecast to remain around -6 to -8 degrees C, indicating moderate instability that may support occasional moderate showers. However, widespread organized convection is not anticipated. Enhanced cloud cover should limit daytime heating, keeping high temperatures near typical seasonal values. Winds will begin increasing on Friday, with the highest values around 15 to 20 knots during the weekend. A gradual drying trend is expected through the weekend as precipitable water values decrease toward near-normal and even below normal values for this time of the year. While a few showers may still filter across the island from time to time accumulations should not be significant. Conditions should remain near seasonal as we approach the upcoming workweek. Temperatures are expected to remain near to slightly above seasonal norms.&& .AVIATION... (18Z TAFS) Issued at 148 PM AST Tue Mar 24 2026 Mainly VFR conditions expected across all terminals, with brief MVFR/IFR conds possible in SHRA, particularly at TJPS/TJSJ thru 24/23Z. VCSH/SHRA expected across TJSJ/TIST/TISX terminals thru 24/22-23Z. TSRA/SHRA with isolated VCTS may result in lower CIGs and brief VIS reductions at TJPS. NE winds btw 08-12 kt, becoming light and VRB aft 24/23Z. && .MARINE... Issued at 148 PM AST Tue Mar 24 2026 A surface high pressure north of the region will promote light to moderate northeasterly winds today, veering from the east tomorrow onwards. The latest altimeter scans reported seas between 3 and 5 feet, with areas reaching 6 feet near the Atlantic offshore waters. Across the coastal areas, the nearshore buoys reported seas between 3 and 4 feet over Atlantic waters, while the buoy at Ponce remained between 1 and 2 feet. On Thursday, as the frontal boundary extending from the western into the central Atlantic dissipates, the local pressure gradient will tighten as another surface high pressure builds over the Western Atlantic, maintaining moderate easterly winds resulting in choppy seas across the regional waters. && .BEACH FORECAST... Issued at 148 PM AST Tue Mar 24 2026 No changes were introduced to the beach forecast. The moderate risk of rip currents is expected to continue across northern and eastern portions of Puerto Rico, including Vieques and Culebra, and the U.S. Virgin Islands, while southern Puerto Rico should remain in a low risk. As mentioned in the Marine section, nearshore buoys have been reporting seas between 3 and 5 feet, with the exception of Ponce (1 - 2 feet). Although there’s no high risk, beachgoers should exercise caution as life-threatening rip currents can still be present along the beaches under a moderate risk. Global model solutions suggest the arrival of a northerly swell early next week, likely to increase breaking waves over northern-facing beaches of Puerto Rico and the U.S. Virgin Islands and result in hazardous conditions for beachgoers. Residents and visitors should monitor the latest beach forecast updates for potential hazards, including life-threatening rip currents and even high surf conditions. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...None. VI...None. AM...None. && SHORT TERM/AVIATION...GRS LONG TERM....MMC PUBLIC/MARINE/BEACH FORECAST...MNG
The San Juan radar (TJUA), 70 km away, was scanning. The volume nearest the first event began at 20:49 UTC.
13 flash flood, 9 flood, 1 thunderstorm wind. Local standard time, as filed.
Heavy rainfall produced a rapid rise in water levels at the Puente El Coqu low-water crossing along a tributary of the Guayan’s River. Floodwaters overtopped the crossing, creating hazardous travel conditions. No injuries, fatalities, or property damage were reported.
Heavy rainfall produced flash flooding at Ernesto Ramos Antonini School in Yauco. Floodwaters accumulated rapidly on the school grounds, causing flooding in the affected area. No injuries, fatalities, or evacuations were reported. The flooding was associated with intense rainfall that affected portions of southwestern Puerto Rico.
Heavy rainfall triggered flash flooding in southern Yauco, inundating portions of Roads 127 and 128. The roads became impassable, resulting in hazardous travel conditions and temporary transportation disruptions. No injuries, fatalities, or structural damage were reported.
Heavy rainfall caused rapid rises along a tributary crossing PR-5516 in Adjuntas. Floodwaters overtopped a bridge located between Selecto Supermarket and the Sweet and Frozen business, making the roadway impassable and disrupting local travel. No injuries or fatalities were reported.
Heavy rainfall caused R o Loco to rise rapidly, flooding portions of Road 335 in Barrio Barina. The roadway became impassable and was temporarily closed to traffic, causing transportation disruptions in the area. No injuries, fatalities, or structural damage were reported.
Heavy rainfall caused a river to overflow onto PR-891 near kilometer 13.9 by the Volleyball Monument in Corozal. Floodwaters covered the roadway, forcing the closure of the road in both directions after it became impassable. The flooding resulted in temporary transportation disruptions, but no injuries, fatalities, or structural damage were reported.
Heavy rainfall caused a river to overflow onto PR-818 in Barrio Cibuco near the sewage treatment facilities in Corozal. Floodwaters covered the roadway, forcing its closure in both directions after it became impassable. No injuries or fatalities were reported.
Heavy rainfall caused a river to overflow at Puente Bull in Naranjito. Floodwaters overtopped the roadway, forcing its closure in both directions after it became impassable.
Heavy rainfall caused a creek to overflow in Sector Paracaochero near Camino Los Cruces in San Juan. Flash floodwaters inundated two residential units near Aceros de Am rica, resulting in flood damage to the affected properties. No injuries or fatalities were reported.
Heavy rainfall caused the R o Cibuco to overflow and inundate portions of PR-675 in Vega Alta. Floodwaters covered the roadway, making it impassable and disrupting travel through the area.
Heavy rainfall caused the R o Cibuco to overflow, resulting in flash flooding across multiple roadways in Vega Alta. Floodwaters inundated portions of PR-620, PR-647, PR-675, PR-690, and PR-676, creating hazardous travel conditions and temporary transportation disruptions. Debris and sediment deposited by the floodwaters required cleanup operations before affected roadways could safely reopen.
Persistent heavy rainfall caused the R o Cibuco to overflow its banks near the PR-2 interchange at Exit 22 in Vega Alta. Floodwaters inundated the highway, rendering portions of the roadway impassable and disrupting transportation along a major traffic corridor.
Persistent heavy rainfall caused the R o Cibuco to overflow its banks near PR-160 approaching PR-2 in Vega Baja. Floodwaters inundated the roadway, rendering it impassable and stranding several motorists. Emergency response actions were required to address the hazardous conditions and assist affected travelers. No injuries or fatalities were reported.
A car was stranded with a person inside due to flooding waters at exit to pr-22 toward avenue Jose de Diego.
Flood waters were affecting a parking lot of a building near a dairy corporation. Several cars were parked over the parking area.
Flood waters affected a house in 124 Ponce de Leon and nearby areas. Standing water was observed inside the first floor of the house.
Gusty winds from a thunderstorm resulted in downed trees that brought down electrical lines onto the roadway obstructing traffic near PR-455 KM 12.
Floodwaters from Rio Culebrinas impacted PR-110 KM 9.9 near Valle Encantado in sector Los Cocos. At the time, the USGS river sensor measured 22.4 ft.
Emergency managers reported flooding along PR-676 KM 1.6, near Mariposario Bosque la Vega in Vega Alta.
Emergency managers reported flooding along PR-2 near Ileana de Gracia high school.
Broadcast media shared on social media a report from floodwaters along PR-3 in direction to Tropical Beach in barrio Hucares in Naguabo.
Rio Yauco went out of its banks in barrio Barinas, near the treatment plant of Yauco in PR-335. The road was impassable.
Emergency management reported flooding along PR-31 in Naguabo due to the Rio Blanco overflowing its banks.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Puerto Rico in 2026Every state in 2026This day in weather historyWarnings in Puerto Rico, March 2026
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-30. Each event’s entry at NCEI: 1327959, 1327960, 1327961, 1327964, 1327965, 1327967, 1327968, 1327975, 1327980, 1327982, 1327985, 1327987, 1327991, 1328034, 1328033, 1328035, 1328036, 1328038, 1328039, 1328040, 1328041, 1328042, 1328043.