Thursday, March 16, 2023

Lingering Cold

Temperatures have been volatile in Alaska over the past month or so, but overall the past 5-6 weeks have produced more cold than warm weather, and this week is certainly on the cold side for much of the state.

Last night dropped into the -20s and -30s Fahrenheit in many of the colder locations: click to enlarge the map below.


This kind of cold is a bit unusual for the middle of March, although nowhere near record territory.  For instance, today's record low at Bettles is -49°F, and just two years ago Bettles saw a remarkable -39°F on April 9.  Read more here on the great April 2021 cold snap.

It's interesting to note that the northern interior has had an unusual number of days with much colder conditions than in, say, Fairbanks this winter.  For example, Bettles typically sees half a dozen days with a low temperature 25°F colder than Fairbanks, but there have been 13 such days this winter.  This is the fourth straight winter with 10 or more such days.

Here's this morning's mid-atmosphere (500mb) map, courtesy of Environment Canada.  A deep trough extending south from the Arctic means a cold air mass, a weak pressure gradient means light winds, and with the main jet stream activity far to the south, clear skies provided the final ingredient for sharp overnight cooling.

Views from the FAA webcams this afternoon are simply glorious; here's Bettles and the Chandalar Shelf DOT site:

No comments:

Post a Comment