It feels like July out here.
For anyone in the eastern half of the US, mid-May is behaving like midsummer. A premature heat wave has smashed records.
Look at Boston. Tuesday hit 96 F. The record for this date? 90 F back in 1947. Dulles Airport near D.C. saw 94 F, breaking its own May 19th best of 92 F. Philadelphia reached 96 F on Monday. The previous record was 94 F in 1962 just barely held the line before this.
What causes this?
A high-pressure ridge.
Specifically the Bermuda High. It hangs over the Atlantic east of North America, steering hurricanes in the summer but currently pulling warm humid air from the south clockwise.
Why it matters more than just “summer coming early”
It isn’t as brutal as the triple-digit sweltering that hit the Southwest in March. Still temperatures across the Mid-Atlantic to the Northeast are sitting in the 90s. Way ahead of schedule.
The humidity is rising too.
Dew points are in the 60s. Marc Chenard a meteorologist at the NWS Weather Prediction Center notes it’s the highest level of this year. It won’t beat the dog days later in the summer but for May it is significant.
Health risks are real though. People aren’t acclimated. Early year heat catches you off guard. The NWS HeatRisk tool shows a “major” risk zone—second highest category—from D.C. up to Boston.
Worst part? Overnight lows are staying warm. Your body can’t cool down. There’s no recovery.
“Relatively high overnight temperatures mean your body doesn’t get a chance to cool off and recover,” Chenard said.
Climate change is pushing the pedal here.
Heat waves are getting stronger, longer, more frequent. They’re bleeding into spring and fall too. A Climate Central tool says this specific heat event is two to five times likely because of climate change alone.
So how long until relief comes?
Short lived for the north. A back-door cold front arrives Wednesday. First a traditional northwest front hits then winds shift northeast. That switch reinforces the cold keeps the heat at bay for the Mid-Atlantic and Northeast.
The Southeast isn’t getting out free. Drought continues there. Wildfire risks climb as it stays sultry.
Why do we complain so much about heat that hasn’t even reached July levels? Maybe we don’t deserve it.
