A dangerous flash flood threat is escalating for approximately 60 million people across the Northeast, Mid-Atlantic, and southern New England, with heavy rainfall expected to persist through Monday night. The saturated ground from weekend storms has created prime conditions for widespread flash flooding.
NOAA's Weather Prediction Center has issued a Level 3 out of 4 risk for flash flooding in New York City, Long Island, coastal Connecticut, Rhode Island, and southeastern Massachusetts. A Level 2 risk extends across a broader area, including Boston, Philadelphia, Washington D.C., Baltimore, and Pittsburgh.
The region experienced severe storms over the July 4 holiday weekend, beginning late Friday afternoon, which led to the cancellation of some outdoor events. Powerful wind gusts downed trees and power lines, leaving more than 280,000 customers without electricity early Monday.
New York City Mayor Zohran Mamdani urged residents in basement apartments to be prepared for potential evacuations on Sunday, and the city opened public schools as temporary shelters. The heavy rainfall on Sunday prompted these warnings.
According to the FOX Forecast Center, Monday's downpours could bring rainfall rates of 2 to 3 inches per hour. Combined with rainfall from Sunday, storm totals are anticipated to range from 3 to 6 inches across the region, with some isolated areas potentially receiving over 8 inches. A Flood Watch remains in effect for over 40 million people through Monday evening.