In the Northeast, the dry spell from April carried over into much of May 2021. This continued to raise drought concerns as it seemed the dry weather would never end. Much needed rainfall finally arrived late in the month, but it unfortunately occurred over the Memorial Day weekend. This rain was coupled with rather chilly weather, which didn’t make it feel like the unofficial start of summer.
High pressure kept the region cool to start, although the pattern wasn’t completely quiet as several frontal systems passed through on the 3rd to the 5th. These brought some rain, but this only amounted to 0.50 to 1.00” at most, which didn’t quench the moisture starved ground enough. The disturbances did allow for a few stronger storms that led to three tornadoes; two EF-1s in Mount Pleasant, MD, and then another shorter-lived EF-0 also near Marston, MD. Lewisetta, VA also witnessed a brief tornado that was originally mistaken for straight-line wind damage.
After a few smaller disturbances the following week…well, nothing happened. High pressure and stubborn ridging left the Northeast locked into a dry pattern. Temperatures were more or less seasonable during this time, and with not much humidity it was rather pleasant. By the 3rd week, temperatures finally started bumping up into 80s and even 90s, to the point of breaking records. For example, Scranton, PA reached a record high of 89 degrees on the 21st, while Baltimore, MD hit a record of 93 degrees on the 22nd.
On the 26th, a warm front shoved humid air into the region, bubbling more locations into the 90s. In fact, Philadelphia, PA topped out at a record of 91 degrees! This heat provided fuel for severe storms across the Mid-Atlantic and Northeast, particularly Maryland through New Jersey and into western portions of New England. These storms created gusty winds that damaged trees and some structures in their wake.
Tree damage in Bridgewater, NJ on May 26th. Picture courtesy of Meteorologist John Leo.
Following a brief calm period, a surge of rain fell over Memorial Day Weekend, making for one of the coolest and wettest in recent memory. Many places had trouble warming past the 50s, with even 40s in far interior spots. Newark, NJ managed a high of only 53 degrees for both Saturday, the 29th and Sunday, the 30th. This set a new record low maximum temperature for the weekend. Along with the chilly temperatures, several inches of rain fell, which made up for the ongoing drought across the region. The highest rainfall amounts were in New England and along the coasts of NJ, DE, and MD where 2.00”+ fell, giving the area a 1.00 - 2.00” surplus of precipitation for the month.
This cooler than normal holiday weekend aided in pushing the monthly average to near normal despite the warm spells. Even though there was a prolonged dry stretch through the middle of the month, the wet end to the month was able to stave off further drought impacts.