Correction: An earlier version of this article misstated in a headline that December was warm and rainy. It should have said warm and dry.
New Year’s Day was the warmest on record for Juneau, following on the heels of a December that was unseasonably warm and dry, according to the National Weather Service.
The temperature reached 46 degrees at the Juneau International Airport on Tuesday, breaking the previous record (set in 1962) by one degree. It was also the rainiest New Year’s Day on record, according to NWS. It rained 1.73 inches at the airport, breaking the previous record of 1.38 inches, set in 2015.
The warm, rainy holiday was a continuation of a warm, rainy stretch at the end of December. Most of December was drier than usual, according to NWS numbers. A total of 5.63 inches of precipitation fell, which was a departure from the average rainfall of 5.84 inches that Juneau usually experiences in December.
December had an average temperature of 33.3 degrees, according to NWS data. Though it was warmer than the usual December, it still didn’t crack the top 10 Decembers on record. The highest average temperature for a month of December came in 1943, when it was an average of 37 degrees.
The Arctic jet stream didn’t bring cold air from up north this December, NWS Juneau Forecaster Kimberly Vaughan said Wednesday.
“We just never got the colder air from the north to come in,” Vaughan said. “A lot of our weather came in from the southwest and the south, so we didn’t get the colder air that we need to be able to bring in colder temperatures and snow.”
At the end of the month, the rain finally came to close out 2018. Forecasters referred to the stretch of warm, rainy weather as a Pineapple Express in their writeup. They weren’t referring to the 2008 movie of the same name, as a Pineapple Express in weather parlance refers to a strong flow of moisture that comes up from the south and runs along the Pacific coast. It’s also referred to as an “atmospheric river.”
Vaughan said the national NWS forecast for January calls for a warm, wet month in Southeast.
Monthly averages across Southeast were about 3.8 degrees above normal. Yakutat was 5.8 degrees above normal, and also set a record for its warmest Jan. 1 ever (beating a record set on Jan. 1, 2018). Ketchikan had the coolest December, experiencing temperatures just 2.3 degrees above its usual December temperatures.
• Contact reporter Alex McCarthy at 523-2271 or amccarthy@juneauempire.com. Follow him on Twitter at @akmccarthy.