Patchy frost this morning as lows reach low-to-mid 30s in suburbs

Low temperatures this AM

Low temperatures this AM

Low temperatures this morning more closely resembled late March than late April, with many locations in our north and west suburbs dipping near the freezing mark.

Officially, Dulles Airport fell to 33, BWI Airport 35, Warrenton-Fauquier Airport 33, and Frederick (at least) 32. These lows are about 10 degrees below average (average lows this morning are 44 at Dulles and 45 at BWI).

These locations were all under a frost advisory due to the expected chill.

“31F here in northern Carroll County with frost on the cars,” CWG reader Chris Smolinski commented just before 7 a.m.

Closer to the city, it was milder (and no frost advisory was in effect), with Reagan National’s dropping to just 41 (its normal low is 49).

While the chill may have seemed on the late side for the region, it’s actually pretty normal.

“At Dulles Airport, the 1981-2010 average date of the last spring freeze is April 21,” CWG’s Justin Grieser wrote in a post last year.

In 17 of the 31 years between 1981 and 2011, the last freeze occurred after April 15 at Dulles, Grieser found.

“In fact, Dulles has seen its last freeze during May in 6 of the last 30 years.” Grieser added. “The latest freeze on record was a reading of 31 degrees on May 22, 2002.”

The date of BWI’s average last freeze is April 11 Grieser reported.

This morning’s lows were well above their records at the respective airports, which are:

Reagan National 30 (1885)
Dulles 27 (1975)
BWI 32 (1875)

Also on Capital Weather Gang

D.C. area forecast: Cooler than normal week ahead, with a few shower chances