Mercury reaches 90s again at BWI

The temperature at BWI-Marshall airport topped 90 degrees again on Monday, reaching 91 degrees during the afternoon.

UPDATE: The official high Monday at BWI was 92 degrees. Earlier post resumes below.


It was 93 degrees at The Sun's weather station at Calvert and Centre streets downtown. Temperatures also reached the 90s at Hagerstown, Martin Airport, Washington Reagan National Airport and Dulles Airport in Virginia.

The high was not close to the record for the date - 96 degrees set back in 1991.


Monday was the fifth day of 90-degree weather for Baltimore so far this year. We hit 90 degrees at BWI on April 6 and 7. The high on May 26 was 91 degrees, and we went one degree higher - 92 - the following day.

The average daytime high temperature for Baltimore on May 31 is 79 degrees. It climbs to 86 degrees by the end of June, and tops out at 88 degrees in the third week of July.

May 2010 ends with an average temperature of about 67 degrees, which is more than 4 degrees above the long-term average for the month, and the warmest May since 2004, which averaged 69.8 degrees at BWI. The high for the month was 92 degrees, on the 27th. The low was 35 degrees, on the 10th. Hardly seems possible now. It's also worth noting - again - that the last of the December and February snow piles finally melted at BWI during the first week of May.

Cooling degree days in May - a measure of the demand for energy for cooling - were running more than twice the norm for the month. Watch for that on your next electric bill. I know my AC is cranking.

The month of May in Baltimore is also ending with about 3.5 inches of rain - about a quarter-inch below the long-term average.

(SUN PHOTO/Algerina Perna, at Fort McHenry, May 31, 2010 ... Looks like "Sunday Afternoon on the Island of Grande Jatte," the Georges Seurat painting, detail, lower right. Except for the cannon.)