A chilly Ocean City in May 2007 - Sun photo by Glenn Fawcett 

Many neighborhood swimming pools will be opening up for the season this weekend. And a few brave souls may be ready to take a plunge into the Chesapeake or the Atlantic as the Memorial Day holiday marks the unofficial start of summer in Maryland.

But it's going to be a breath-taking experience. Here's how Andy Woodcock - a National Weather Service forecaster out at Sterling, put it in this morning's forecast discussion:

"FUNNY THING...WHEN I WOKE UP THIS MORNING THE FIRST THING I THOUGHT
OF WAS "COMMUNITY SWIMMING POOLS WILL BE DOWNRIGHT COLD THIS
WEEKEND." NO IDEA WHY I THOUGHT THAT...BUT CERTAINLY TRUE. WEATHER LOOKS TO
BE QUITE NICE FOR THE MEMORIAL DAY WEEKEND...BUT W/ OVERNIGHT LOWS STILL IN
40S...AND PLENTY OF COLD RAINFALL DURING THE PAST FEW WEEKS...THAT WATER WILL
BE CHILLY. THOMAS POINT LIGHT WATER ONLY 60. BRR."

Well, our low overnight here at Calvert & Centre streets was 52 degrees, but out at the airport they reported a low of 45 degrees - almost 10 degrees below the long-term average for this time of year. The forecast for tonight puts the BWI low at 47 degrees, creeping to 49 Friday night and 51 by Saturday night.

Daytime highs are running about 5 degrees too cool for this time of year. But the forecast has them rising to  the mid-80s by Memorial Day. If you're headed for the beaches, however, don't expect to see temperatures that warm. Here's OC's forecast.

As for water temperatures,  Ocean City is reporting 58-degree water at the Inlet. The readings are 60 degrees at Annapolis and Tolchester. A defibrillator is advised.

As for the pools, well, I'd advise alerting the lifeguards before you dive in.