A new month, a new school year, and a new air mass on this final day of the meteorological summer. Everything will seem fresh this week as cooler, drier Canadian air takes over our weather.

The overnight low was just 59 degrees out on the WeatherDeck this morning. At BWI-Marshall, the low was 62 degrees. We've been that cool only twice this month, as compared with our unusually cool July, which saw eight mornings in the 50s. 

Here are some other overnight lows across the region. (The lows for the 24 hours ending 8 a.m. Aug. 31 had not been posted at this writing, so be careful to check the date on the map.)

A quick check found lows of 62 at Dulles International Airport; 64 degrees at Reagan National; 66 degrees in Annapolis; 58 degrees in Hagerstown; 57 at Martinsburg.

The cooler weather comes with high pressure building in from the Great Lakes. You can see the clear air just to our northwest in the satellite view above. The stalled cold front that brought us our showers late last week remains to our south, and we may be stuck under its cloud deck for a time today until that boundary finally gets pushed out to sea.

That will clear the way for what should be a dry, sunny week, with highs in the 70s, climbing to the low 80s after mid-week ... "quite late-Septemberish," the forecasters said this morning.