Hurricanes and Tornadoes That Hit Willow Grove, PA

The nearest NOAA station with 1991–2020 climate normals is Philadelphia NE Airport, PA, 7 miles southeast of Willow Grove at 100 feet. July is the warmest, with an average high of 88°F and low of 69°F; January is the coolest, at 42°F and 27°F. September is the wettest at 4.5 inches of precipitation on average and February the driest at 2.6 inches; the year adds up to 45.0 inches over 75 days with at least a tenth of an inch. June to November, the hurricane season months, bring 53% of the year's precipitation (23.7 of 45.0 inches); the other six months are drier. September has brought the most of the 38 tropical systems that passed within 75 miles (14); a normal September there has highs of 79°F and 4.5 inches of precipitation. Highs reach 90°F on about 29 days a year, almost all from May to September. Lows fall below freezing on about 88 nights a year. That 45.0 inches is more than at 76 of the 148 Pennsylvania stations used on this site (51%). Oreland, 4 miles southwest, has its own station (Norristown, PA): 50.7 inches a year, 5.7 more than here, and a July average high of 89°F against 88°F.

Water temperature at the NOAA tide station Bridesburg, PA, 12 miles south, averaged 80°F in July and 38°F in February over 2021–2025. It averaged 80°F or warmer from July. Sea level at the Philadelphia tide gauge, 15 miles from Willow Grove, has risen 1.24 ± 0.04 inches per decade from 1900 to 2025, NOAA's linear trend; at that pace it is 12.4 inches in a hundred years. That is faster than at 73 of the 144 U.S. gauges with a NOAA trend.

Since 1996, the National Weather Service has logged 639 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Willow Grove: 396 thunderstorm wind reports, 155 flash floods, 70 floods, 12 lightning strikes and 6 heavy rain events. They killed 5 people and injured 19, and the NWS estimated $86.7 million in property and crop damage. The strongest thunderstorm gust on record here was 109 mph, on October 31, 2019. July has had the most flash floods, 52 of 155. Of the 788 Pennsylvania cities on this site with a flash flood on record, 717 have had fewer than Willow Grove.

Flood insurance policyholders in Willow Grove's ZIP code 19090 have filed 49 claims with the National Flood Insurance Program since 1979, and were paid $1.0 million for buildings and contents, in the dollars of each year. The most came from Hurricane Ida in 2021: 10 claims (20% of all) and $355,000. The year with the most claims was 2011, with 13. 53% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 553 Pennsylvania cities on this site with 10 or more claims, 273 have fewer than Willow Grove.