One of the coolest Mays on record in Baltimore slipped away overnight after leaving Maryland's air conditioners mercifully silent for a month.
That could change by this weekend, when temperatures are expected to climb into the high 70s and 80s. And the summer ahead could still be a scorcher, even though climatologists say they're expecting near-normal temperatures and rainfall.
May, at least, will go down in Baltimore's weather books as having mostly dry, sunny days, with temperatures averaging 59 degrees.
It was pleasant enough to lull Marylanders into keeping their air conditioners off and opening their windows, thereby postponing any reckoning with needed repairs.
That didn't go unnoticed by the repair companies. "Everybody's seeing the same thing - probably in the neighborhood of a 20 percent decrease in business," said Jeff Stagnoli, general manager of Blue Dot of Maryland, an air-conditioning and heating contractor based in Elkridge.
And because homeowners don't yet know whether they need replacements, business has been slow for air conditioning manufacturers, too, Stagnoli said. Some have been extending their customary May rebate offers into June.
Larger companies, he said, have been able to keep their service crews busy by calling customers with maintenance contracts and accelerating the twice-yearly system checkups that usually take until midsummer to complete.
But "I can imagine that for some small companies out there, it has been difficult to provide the guys with a full workweek," Stagnoli said.
Temperatures averaged well below normal for 15 straight days at the end of last month. They rebounded over the Memorial Day weekend, but not enough to crowd the state's beaches, where officials reported holiday tourism was off.
It might have been that Marylanders hedged their bets and stayed closer to home. The Memorial Day weekend saw plenty of people eager for a weekend dip at Hillcrest Swim Club in Parkville, according to Rachel Fleming, one of the pool's head lifeguards.
"The weather was really good Saturday morning," she said. "It rained halfway through, but even then people were sticking it out."
When the rains came again Monday afternoon, "everyone stayed in the pool," she said. After so many months on dry land, when opening day finally arrives, "everybody makes a big effort to be here."
On the whole, last month was relatively dry, and often perfect for outdoor activity.
Rainfall was more than an inch below average, with 23 days rated clear or partly cloudy and just eight that were cloudy.
Also, more than 88 percent of the 2.6 inches of rain that did fall at Baltimore-Washington International Airport last month arrived on just two days - May 20 and 24.
The cool weather last month was the result of persistent low-pressure systems off the coast of the northeastern United States.
Counterclockwise air flow around those lows kept cool air from Canada or the North Atlantic pouring into the Northeast, according to James Brotherton, a National Weather Service meteorologist at the Sterling, Va., forecast office.
The pattern placed May 2005 into the ranks of the coldest Mays since record-keeping began in Baltimore, in 1871.
May 2005 averaged just 59 degrees through the 30th - about 4 degrees below the 30-year average. That's a tie with 1907 for the second-coolest May on record here. But that ranking could slip after yesterday's temperatures are included in the calculation.
There were just three days last month that reached the 80s, compared with 19 days in May 2004. Last year's was the third-warmest May on record, with an average of 69.8 degrees.
On three mornings last month, the low sank into the 30s.
The coldest May on record here was in 1967, when temperatures at BWI averaged just 57 degrees.
The cool May gives climate forecasters no clear indication whether the summer that follows will be cool or hot.
"The National Climate Prediction Center ... is calling for near-normal temperatures and precipitation for this coming summer in Baltimore," Brotherton said.
The cold May in 1967 was followed by a summer that averaged 73.8 degrees, a tie for the 10th-coolest summer in Baltimore since 1950.
But of the five coolest Mays in Baltimore since 1950, three were followed by summers that were cooler than average; two preceded unusually warm summers.
May 2005 was one of the coldest on record, although its exact rank won't be known until this morning. Here are the coolest Mays on record, with average temperatures:
2005: 59.0 (through May 30)