A late-summer shot of hot, humid Southern air pushed temperatures in Baltimore to a near-record record 93 degrees by 1 p.m. today, prompting city school officials to cancel afternoon classes. It was 97 degrees at the airport, tying a 21-year-old record.
City school children were sent home at 12:30 p.m., many probably leaving with high hopes of doing it again tomorrow, when the high is again expected to reach the 90s.
But by Wednesday, a cold front from the Midwest is expected to bring highs down into the 80s, followed by more autumn-like highs of 75 degrees Thursday and Friday, the National Weather Service says.
Autumn itself arrives officially next Monday, Sept. 23, at 7:48 a.m.
The record highs for this date were set in 1970, with a 95-degree mark downtown and 97 at Baltimore-Washington International Airport.
At Washington's National Airport, the overnight low of 73 degrees tied a 110-year-old record for the warmest night ever for the date.
Forecaster Bill Miller said today that the hot and muggy conditions are the result of a very warm but stable air mass from the South.
The transition day between summer and fall temperatures comes Wednesday, with highs in the mid-80s, he said.
Miller said it's not unusual for hot weather to pop up around Baltimore in mid-September. The daily records slip from near 100 degrees in the first days of September to the low 90s at month's end.
So far this year, the weather service has counted 57 days with highs above 90 degrees. The record is 63 days, set in 1988. At BWI, there have been 50 days of 90-plus weather, still short of the 54 counted in 1988.
As the days get shorter, Miller said, the overnight lows for the rest of the week may feel a bit chilly.