Coolest night since July 4; more coming

That will increase the chances for showers and thunderstorms by late Wednesday - 50 percent by Wednesday night. Thursday, too will feel hot and muggy.

But that looks like the end of this hot spell for a while. Forecasters say the next cold front will push through out of the Great Lakes sometime on Thursday. Just how severe the storms accompanying the frontal passage will be remains in doubt. Forecasters say it depends on the timing.

If the front moves through in mid-afternoon - at the peak of the daytime heating - we could see a gusty storm front like the one on Sunday, they say.

Behind the front we are told to expect cooler, drier conditions. "Lows Thursday night may even drop into the 50s in higher elevations," according to this morning's forecast discussion.

"Northwest flow aloft will provide relief to the summer heat and humidity. Daytime highs in the low to mid-80s during these days will be the lowest in at least two weeks. with overnight lows in the 50s and 60s being the coolest since the first few days of the month."

So far, July 2010 is averaging 82 degrees, which is 5.5 degrees above the average July at BWI. The average is likely to drop some this week as cooler conditions prevail. But if the month ended today, this would rank as the hottest July for Baltimore in 138 years, beating the current record of 81.7 degrees, set in 1872, the year after they began keeping official records.

(SUN PHOTOS: Top: Druid Hill Park pool, Karl Merton Ferron; Bottom: Six Flags, Jerry Jackson, 2010)