Hundreds of flight cancellations have been reported in Texas as storms roll over the state, leading to flash flood warnings and school closures, while punishingly high temperatures in the north-east break records before a dramatic cool-down.

Nearly 150 flights were canceled or delayed at Dallas Fort Worth international airport on Wednesday and nearly 700 delayed on Tuesday, according to Flightaware. The FAA issued a ground stop in Dallas and Love Field.

North Texas is expecting at least 1in of rain from Wednesday through Friday with chances of isolated flooding, according to the National Weather Service, with the greatest chance of flooding on Thursday.

A severe thunderstorm watch is also in place over central Texas. The weather service warned that some areas could record between 3in and 5in of rain.

In the north-east, Wednesday marks the last day of a heatwave as severe storms are expected to roll through dropping temperatures down from the mid-90sF to the mid 60sF. Temperatures in New York City hit a high temperature of roughly 92F in Central Park on Tuesday.

“The seemingly endless temperature roller-coaster this spring will continue through the holiday weekend with another sharp cooldown across the northeastern quarter of the nation,” said Brett Anderson, a senior meteorologist at AccuWeather.

“This persistent pattern of major temperature swings has clearly wreaked havoc on plants and agriculture across the north-east, as the region has gone from record-breaking heat to hard freezes, then back to leaf-withering heat and now another chilly stretch,” he added.

The unstable spring season weather has led to rainfall deficits across portions of the mid-Atlantic and south-east. Rivers, including the Potomac and Shenandoah, are experiencing record-low flow rates, and Baltimore officials are encouraging voluntary water conservation, Accuweather said.