Tuesday's temperatures reached a record high for 2013 in Baltimore, and it could get hotter still with the heat index expected to near 100 degrees Wednesday and surpass it Thursday.
Forecasters observed a high of 93 degrees at Baltimore-Washington International Thurgood Marshall Airport on Tuesday afternoon. That was slightly hotter than the 92-degree highs reached Monday and May 30.
But the National Weather Service is forecasting highs in the mid-90s both Wednesday and Thursday, with high humidity making it feel hotter and bringing a chance of afternoon storms.
Dew points could hover in the lower 70s Thursday, a level that makes the air feel thick and uncomfortable. That could bring the heat index to 103 degrees, according to the weather service.
The heat wave is a mild one, however, compared with recent summers. BWI had already reached 100 degrees by this time each of the past three years. The region spent 16 days in the 90s or hotter in June 2010, and nearly a dozen in June 2012.
There have been six days at or above 90 degrees at the airport so far this year, half of them this month. In a normal year, eight days reach 90 degrees or hotter by the end of June in Baltimore, according to the National Climatic Data Center.
The coolest June in Baltimore in recent history was in 2009, when temperatures never got out of the 80s.