Puerto Rico Severe Flash Flood Warning | Effective 08-31-2026 21:47

Headline: 
Flash Flood Warning issued September 1 at 12:47AM AST until September 1 at 3:15AM AST by NWS San Juan PR
Event: 
Flash Flood Warning
Urgency: 
Immediate
Effective: 
August 31, 2026 - 9:47pm
Expires: 
September 1, 2026 - 12:15am
Description: 
At 1247 AM AST, Doppler radar indicated thunderstorms producing heavy rain across the warned area. Between 2 and 4 inches of rain have fallen. Additional rainfall amounts of 2 to 3 inches are possible in the warned area. Flash flooding is ongoing or expected to begin shortly. HAZARD...Life threatening flash flooding. Thunderstorms producing flash flooding. SOURCE...Radar indicated. IMPACT...Life threatening flash flooding of creeks and streams, urban areas, highways, streets and underpasses.
Instruction: 
Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Be especially cautious at night when it is harder to recognize the dangers of flooding. Please report observed flooding to local emergency services or law enforcement and request they pass this information to the National Weather Service when you can do so safely.
SNM: AVISO DE INUNDACIONES REPENTINAS hasta 3:15 AM AST. Evite areas inundadas.
Servicio Nacional de Meteorologia: AVISO DE INUNDACIONES REPENTINAS en efecto para esta area hasta las 3:15 AM AST. Esta es una situacion peligrosa y amenaza la vida. No intente viajar a menos que sea para abandonar un area propensa a inundaciones o bajo una orden de desalojo.
Area Description: 
Arroyo, PR; Maunabo, PR; Patillas, PR; Yabucoa, PR
Forcast Office: 
NWS San Juan PR
Sender: 
w-nws.webmaster@noaa.gov