Thursday, June 20, 2013

An Alaskan Sized Blowtorch

It's been warm the last several days in Alaska. In terms of heat, getting into the 80's and even lower 90's isn't incredibly uncommon in mid June in the middle of Alaska...the benefit of being several hundred miles from cold ocean water plus 20 hours of sunlight. It is uncommon to see this level of warmth working down towards coastal towns like Valdez, where a record high of 89 smashed the old all-time record.

It's also rare to see towns like Nome, on Alaska's west coast, get into the 80's, ever.  They had a record high yesterday of 86, which also tied a record for warmest day ever.

It also is uncommon to see the interior of Alaska deal with this level of heat for as long as they have. Fairbanks will likely hit 80 today for the seventh consecutive day.  In fact, over the last seven days, Fairbanks has averaged out to be warmer for daily high temperatures than we have!

What's the cause of this unusual warmth?  A blocking high situated over the North Slope of Alaska (marked by the red shading on the 500 mb map below).  The high pressure ridge has been situated over Alaska for a number of days and has allowed for clear skies, sinking air, and warming temperatures for much of the state.  The sunshine and warmth has come with a cost in the form of wildfires that have broken out across the Alaskan wilderness.  It's also a rather stark contrast to what Alaskans were dealing with for most of the Spring (cold, record cold, and snow even as recently as  May 18th in Fairbanks and Anchorage.

This ridge of high pressure will break down a bit in the coming days, with temperatures trending closer to normal as a trough deepens across the West. The Bermuda High in turn props up a bit in the East and helps produce a string of low 90's for us early next week while Alaskan temperatures trend much, much closer to normal.