Hurricanes and Tornadoes That Hit San Juan, PR

The nearest NOAA station with 1991–2020 climate normals is San Juan L M Marin Airport, PR RQ, 4 miles northeast of San Juan at 9 feet. August is the warmest, with an average high of 89°F and low of 78°F; January is the coolest, at 83°F and 72°F. November is the wettest at 7.4 inches of precipitation on average and March the driest at 2.2 inches; the year adds up to 60.0 inches over 112 days with at least a tenth of an inch. June to November, the hurricane season months, bring 60% of the year's precipitation (36.1 of 60.0 inches); the other six months are drier. September has brought the most of the 64 tropical systems that passed within 75 miles (27); a normal September there has highs of 89°F and 6.5 inches of precipitation. Highs reach 90°F on about 72 days a year, almost all from March to November. A night below freezing comes less than once a year on average. That 60.0 inches is more than at 7 of the 21 Puerto Rico stations used on this site (33%). Guaynabo, 4 miles southwest, has its own station (Trujillo Alto 2 SSW, PR RQ): 72.9 inches a year, 12.9 more than here, and the same August average high, 89°F.

Water temperature at the NOAA tide station San Juan, La Puntilla, San Juan Bay, PR, 6 miles northwest, averaged 86°F in September and 80°F in February over 2021–2025. Sea level at the San Juan tide gauge, 6 miles from San Juan, has risen 0.85 ± 0.06 inches per decade from 1962 to 2025, NOAA's linear trend; at that pace it is 8.5 inches in a hundred years. That is faster than at 45 of the 144 U.S. gauges with a NOAA trend.

Since 1996, the National Weather Service has logged 936 flood, rain, thunderstorm wind and lightning events that began within 10 miles of San Juan: 406 flash floods, 400 floods, 76 heavy rain events, 46 thunderstorm wind reports and 8 lightning strikes. They killed 11 people and injured 4, and the NWS estimated $5.51 billion in property and crop damage. The strongest thunderstorm gust on record here was 60 mph, on May 14, 2011. May has had the most flash floods, 76 of 406. Of the 86 Puerto Rico cities on this site with a flash flood on record, 82 have had fewer than San Juan.

Flood insurance policyholders in San Juan's 16 ZIP codes have filed 2,731 claims with the National Flood Insurance Program since 1978, and were paid $33.5 million for buildings and contents, in the dollars of each year. The most came from Hurricane Hortense in 1996: 368 claims (13% of all) and $7.8 million, then Hurricane Georges in 1998 with 248 and Flooding in 1981 with 237. 48% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 72 Puerto Rico cities on this site with 10 or more claims, 71 have fewer than San Juan.