July heats up
Vacation's over ... sigh ... and it's way past time to plug in the numbers for July. This is, of course, our hottest month. The average high temperatures peak at 88 degrees during the third week of the month. Then, mercifully, the shortening days and decreasing sun angles begin to work their magic and temperatures start to slip.
But not by much. The average high only drops a degree during July, to 87. And average nighttime lows stick at 66 degrees.
Record high temperatures for Baltimore-Washington International Thurgood Marshall Airport remain in the upper 90s and low 100s all month.
The all-time hottest day on record for Baltimore was on this date - the 10th - in 1936, when air conditioning was rare and Baltimoreans sometimes slept out in the parks to beat the heat in those airless little rowhouses. Don't try that today. It was 107 degrees that day. The most recent new record high set for July was 100 degrees, reached on the 4th in 2002. The coolest record daily high temperature is 97 degrees, set on July 12, 1908, and matched on July 24, 1987.
The coldest July day on record at BWI was just five years ago. On July 3, 2001 the overnight low touched 50 degrees, a day after reaching 51 degrees, a record for a July 2 in Baltimore.
July also still hosts a record set during the first year of official record-keeping for the city. On July 28, 1871 the instruments recorded 2.28 inches of rain, which still stands as the wettest July 28 on the books.
The wettest July was in 1889, when more than 11 inches fell downtown. The driest was in 1955, with just 0.30 inch of rain. Normal July precipitation is 3.85 inches, based on the 30-year record from 1970-2000.
