Juneau to toy with high-temp mark for year Monday; heat advisories issued for parts of Southeast Alaska

Forecast high at airport of 74 degrees just shy of current 2025 peak of 76 set a month ago.

Young entrepreneurs Elias and Keller Bjork, ages 9 and 6, with their mother Joy watching, sell glasses of chilled lemonade for $1 to Juneau residents William and Artemis Anders on Sunday afternoon. The family set up the refreshment stand at the corner of Mendenhall Loop Road and Glacier Spur Road to offer drinks to Mendenhall Glacier visitors awaiting the Capital Transit bus downtown. (Laurie Craig / Juneau Independent)

Monday has a chance at being the warmest day of the year so far in Juneau, although temperatures aren’t likely to top the 80-degree mark that is forecast — along with official heat advisories — in other parts of Southeast Alaska, according to the National Weather Service.

A high of 74 degrees is forecast at Juneau International Airport, just below this year’s current high of 76 degrees set on June 22, Brian Bezenek, a lead meteorologist for the National Weather Service Juneau, said Sunday evening. He noted temperatures are expected to vary at locations around town — although none are expected to reach the 80-degree mark — and a slight change could result in the airport topping last month’s peak for the year.

"We could be off a couple of degrees," he said. "This is what we have right now."

The heat will likely increase the fill rate of Suicide Basin somewhat, but not enough to significantly alter the current prediction of the ice dam being full by Aug. 8, Bezenek said.

"The increased warmth will increase a little bit of melt so it will increase it probably slightly, probably not an extreme amount," he said.

Heat advisories are in effect from 1 to 8 p.m. Monday for several communities in southern Southeast Alaska.

"Warmer conditions will persist through the next few days, with high temperatures for land areas in the inner channels looking to exceed 70°F until Wednesday," a forecast published at about 2 p.m. on the weather service’s Facebook page notes. "Several areas have a high likelihood (greater than 80%) of exceeding 75°F, and temperatures up to 80°F are possible for parts of the southern panhandle on Monday."

"Several Heat Advisories have been issued for areas including Hyder, Ketchikan, and Prince of Wales Island. The highest likelihood of exceeding 80 degrees is expected to be inland areas, such as near Ward Lake in Ketchikan or along Hollis Rd. on Prince of Wales Island, as they are less susceptible to sea breezes."

A heat advisory issued for parts of southern Southeast Alaska on Monday. (National Weather Service Juneau)

The 80-degree mark for heat advisories in Southeast Alaska is a new policy announced in June by the weather service, based on newly available data about people’s susceptibility to heat in the state compared to other parts of the United States. Juneau’s record-high temperature of 90 degrees set in 1975 would not be a heat alert under historical Lower 48 standards — but the city will get its first-ever such declaration the next time 80 degrees is reached.

“The sun angle in Alaska plays a role in 80°F feeling hotter than if you experienced that in Hawaii or elsewhere down south,” the weather service announcement notes. “Closer to the equator, the sun is beating down directly over your head and a wide brim hat can really help. Meanwhile, at this latitude the sun angle is hitting the body more broadly.”

The current warm spell that resulted in temperatures in the 70s in parts of Juneau on Sunday is expected to continue through Tuesday, with a high of about 70 that day before rain arrives Wednesday, according to the weather service’s extended forecast.

• Contact Mark Sabbatini at editor@juneauindependent.com or (907) 957-2306.