Portland was on the verge of hitting 80 degrees today, part of a record-setting week of heat after an unusually cool start to the month.

The temperature at the Portland Jetport had climbed to 79 degrees by 1 p.m., held in check only by a gentle sea breeze.

Sanford was in the mid-80s, said John Cannon, meteorologist with the National Weather Service in Gray.

The record for today was 60 degrees, set in 1946.

“That was broken at 9 o’clock this morning,” Cannon said.

Concord, New Hampshire has set an unprecedented four record-breaking days in a row and Portland has hit three out of four, just missing Tuesday, Cannon said. Tomorrow is likely to be a record as well, when the 70-degree mark set in 1948 is likely to fall.

“Some summers we don’t get stretches like this,” Cannon said. “The irony of this is it’s been a fairly cold March. The first 20 days of March were actually running a little colder than normal.”

The forecast for tomorrow: Patchy morning fog then sunny.

“I’m looking at probably 83 for a high, and that would be another record,” Cannon said.

Portland also set records Sunday and Monday with highs of 70.

Thank the jet stream for the unusually warm weather, both this week and for the past few months. It normally blows from west to east, but recently it has been more south-to-north, pulling warm air from the Gulf of Mexico, said Chris Legro, a meteorologist with the National Weather Service.

“When we get into these situations where it’s a highly north-south flow, it’s tough to break that pattern,” he said Tuesday. “That’s why we’ve seen so many days of nice, warm weather here.”

That weather has accelerated all things spring.

Early arrivals have birders chatting about their sightings, including American woodcocks, red-winged blackbirds, pine warblers and Eastern phoebes, said Mike Windsor, staff naturalist at Maine Audubon’s Gilsland Farm in Falmouth.

Windsor spotted an Eastern phoebe there on March 13. Its average arrival date in Maine is April 7.

“This is kind of a time of anticipation for us nerder-birders,” he said. “There’s a listserv for all these kinds of sightings through the state of Maine. People have been expressing surprise.”

Gardeners also have been spotted earlier than usual.

Shoppers last weekend snapped up the rest of the first crop of pansies grown by Skillins Greenhouses. Last year, the first crop lasted through April, said Mike Skillin, a co-owner of the business, which has locations in Falmouth, Cumberland and Brunswick.

He estimates that business is up 10 percent to 20 percent from where it normally would be at the start of spring.

“We’ll take that. We haven’t seen those kinds of increases for a while,” he said.

At Cumberland County Choppers and Cycles in Portland, customers are buying and taking their motorcycles out of winter storage earlier than usual. Scooter sales also have been active, because of the combination of warm weather and high gas prices.

“It’s pretty busy throughout the day – service and sales,” said Peter Gordon, the owner.

At Gorham Bike and Ski in Portland, the warm weather has been good for the bike part of the business but not so good for the ski portion, said Cody Harris, a saleswoman.

She said the shop started getting busy about three weeks earlier than normal. That includes a group that’s unusual for this time of year: men, who usually don’t show up much until April, Harris said.

Maple sugar producers are also running ahead of their normal schedules.

Jocelia Hartwell of Jo’s Sugar House in Gorham said many in the business pulled their taps from trees last weekend because the sap isn’t running as it normally would. Hartwell’s taps are still in, but only because she hasn’t had time to remove and clean them, a two-day process for her operation.

A rule of thumb says 20 degrees at night and 40 degrees during the day make for a good run of sap. That hasn’t been happening lately, and Hartwell has noticed that the sap is cloudy.

“One place where I have a few tubes coming into a collection point, it was almost milky. I just dumped it,” she said.

It may not help with maple syrup production, but Legro of the weather service said a cold front is expected to come through the area Friday. Even so, he said, temperatures will remain above normal.

Staff Writer Ann S. Kim can be contacted at 791-6383 or at: [email protected]

Twitter: AnnKimPPH