National Weather ServicePuerto RicoFlash Flood WarningArchive to October 1, 2026
Flash Flood Warnings in Puerto Rico
The National Weather Service issued 87 flash flood warnings for Puerto Rico in 2025 and 68 a year on average in 2008-2025; in 2021-2025 it had the 24th most of any state. 2026 through September: 28, 44% below the average of 50 for those months in 2008-2025. San Juan was covered most often (171 times since 2008).
How many flash flood warnings does Puerto Rico get?
Every flash flood warning that covered part of Puerto Rico. 2026 is an outline: the year is not over.
The numbers
| Year | Count |
|---|---|
| 2026 (through September) | 28 |
| 2025 | 87 |
| 2024 | 120 |
| 2023 | 65 |
| 2022 | 87 |
| 2021 | 18 |
| 2020 | 51 |
| 2019 | 32 |
| 2018 | 20 |
| 2017 | 166 |
| 2016 | 36 |
| 2015 | 12 |
| 2014 | 25 |
| 2013 | 38 |
| 2012 | 42 |
| 2011 | 153 |
| 2010 | 125 |
| 2009 | 73 |
| 2008 | 76 |
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
When in the year does Puerto Rico get them?
Sum of 2008-2025; the busiest month is labelled.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
Where in Puerto Rico?
| County or forecast zone | Since 2008 | Since 2023 | Last issued |
|---|---|---|---|
| San Juan | 171 | 41 | May 12, 2026 |
| Naguabo | 152 | 21 | April 7, 2026 |
| Fajardo | 142 | 14 | August 17, 2025 |
| Ceiba | 127 | 12 | August 17, 2025 |
| Rio Grande | 127 | 15 | August 17, 2025 |
| Guaynabo | 123 | 35 | April 17, 2026 |
| Yabucoa | 114 | 17 | September 1, 2026 |
| Bayamon | 113 | 33 | April 17, 2026 |
| Luquillo | 111 | 12 | August 17, 2025 |
| Patillas | 108 | 13 | September 1, 2026 |
| Carolina | 101 | 25 | February 15, 2026 |
| San Lorenzo | 101 | 8 | April 16, 2026 |
The NWS issues these products for counties or forecast zones; a zone can be part of a county or a mountain range.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
The latest flash flood warnings for Puerto Rico in AreaZine's record
NWS San JuanWarningSeptember 19, 2026
Flash Flood Warning: Aguada, Las Marias, Moca and 1 more, PR
Expired 6:30 p.m. EDT, September 19, 2026
NWS San JuanWarningSeptember 7, 2026
Flash Flood Warning: Vega Baja, PR
Expired 4:15 p.m. EDT, September 7, 2026
NWS San JuanWarningSeptember 1, 2026
Flash Flood Warning: Guayama, PR
Expired 3:15 a.m. EDT, September 1, 2026
NWS San JuanWarningSeptember 1, 2026
Flash Flood Warning: Arroyo, Maunabo, Patillas and 1 more, PR
Expired 3:15 a.m. EDT, September 1, 2026
NWS San JuanWarningAugust 9, 2026
Flash Flood Warning: Mayaguez, PR
Expired 6:00 p.m. EDT, August 9, 2026
NWS San JuanWarningMay 23, 2026
Flash Flood Warning: Mayaguez, PR
Expired 5:00 p.m. EDT, May 23, 2026
NWS San JuanWarningMay 12, 2026
Flash Flood Warning: San Juan, PR
Expired 5:00 p.m. EDT, May 12, 2026
NWS San JuanWarningApril 28, 2026
Flash Flood Warning: Comerio, PR
Expired 7:00 p.m. EDT, April 28, 2026
This list is AreaZine's record of the NWS alert feed, kept since April 6, 2026; the counts above come from the complete IEM archive.
Source: National Weather Service alerts (api.weather.gov).
What is a flash flood warning?
A flash flood warning means flash flooding is happening or about to happen: water rising fast in streams, streets or dry washes, usually within six hours of heavy rain or a dam or levee failure. A warning means the hazard is happening, about to happen, or very likely: act now to protect people and property. The national record · Every warning type in Puerto Rico.