As the eastern half of the U.S. goes into the deep freeze (as outlined in Jeff Masters' blog today, the flip side is the record warmth that California and Alaska have been experiencing (for two straight weeks now). All-time monthly records for warmth have been set at numerous locations in both states, something that cannot yet be said to have occurred during the cold waves this month in the eastern U.S.
The 850 mb height temperature anomaly for North America for the period of January 14-24, 2014, illustrates the amazing contrast between the cold in the East and the warmth in the West. NOAA.
Alaska
UPDATE 1/28: The all-time warmest temperature ever observed in Alaska was tied on January 27 when the temperature peaked at 62 °F (16.7 °C) at Port Alsworth. This ties a similar reading measured at Petersburg on January 16, 1981.
The last half of January has been one of the warmest winter periods in the state’s history with temperatures averaging as much as 40 °F above normal on some days in locations in the central and western portions of the state. All time January monthly heat records have so far been established at Nome: 51 °F (10.6 °C) on January 27 (former record 46 °F/7.8 °C on January 7, 1942, POR since 1906), Denali Park HQ: 52 °F (11.1 °C) on January 27 (former record 51 °F/10.6 °C on January 21, 1961, POR since 1922), Palmer: 58 °F (14.4 °C) on January 26 (former record 52 °F/11.1 °C on January 20, 1961, POR since 1949), Homer: 57 °F (13.9 °C) on January 27 (former record 51 °F/10.6 °C on January 23, 1961, POR since 1932), Alyseka: 57 °F (13.9 °C) on January 26 (former record 50 °F/10.0 °C on January 4, 1995, POR since 1963), Seward: 58 °F (14.4 °C) on January 27 (former record 55 °F/12.8 °C on January 7, 2005, POR since 1949), Talkeetna: 47 °F (8.3 °C) on January 25 (former record 46 °F/7.8 °C on January 21, 2004, POR since 1949).
A pool of shallow cool air has prevented monthly temperature records from having been set at some interior locations such as Fairbanks where the high of 45 °F (7.2 °C) on January 24th was well short of the monthly record of 52 °F (11.1 °C) set on January 16, 2009.
In fact, on Sunday (January 26) the temperature at around the 10,600 ft. level (about the 700 mb level) rose to freezing above Fairbanks, the warmest ever measured for any month from November to March (inclusive). The same also occurred at Ketchikan where at the 850 mb level (around 5,000 ft.) the temperature soared to 53.6 °F (12 °C), a January record for any location anywhere in the state.
However, in spite of the shallow cool air at the surface, some interior locations have reached record territory. Most incredible is an unofficial report from an automated platform at Boli Lake, south of Delta Junction, which reported 60 °F (15.6 °C) on January 26. If accurate, this would be just 2 °F shy of Alaska’s all-time state monthly record of 62 °F (16.7 °C) set at Petersburg on January 16, 1981. Of course, Petersburg is on the southeast Alaskan Peninsula where mild Pacific air sometimes intrudes during the winters. Boli Lake is in the heart the Alaskan interior, normally one of the coldest regions in the state during January.
Extreme January Warmth Elsewhere
The extreme warmth experienced so far this month in Alaska has also been noted in Canada’s Yukon Territory where Carmacks has averaged 22.5 °C (40.5 °F) above average for the past 10 days (-12.1 °C low, 2.2 °C high versus a normal of -33.6 °C low and -23.8 °C high). In Iceland, Reykjavik is so far experiencing its 8th warmest January on record with a POR beginning in 1871. Greenland has also been exceptionally warm with the normally frigid Summit Station (at 10,500 ft.) yet to record a -50 °C (-45.5 °F) reading this month (which is around what the entire monthly daily minimum average should be).
The warmth over Alaska, the Arctic, Greenland, and Iceland, while so cold in the eastern U.S., can be illustrated by this 500 mb anomaly map of the northern hemisphere forecast for February 1st and produced on January 27th. Note how the polar vortex has been split into two lobes. I am not sure how unusual or not this is. Map courtesy of Guy Walton.
Meanwhile, of course, California has seen an unprecedented 14 consecutive days of record-breaking high temperatures including several all-time monthly records such as the 79 °F (26.1 °C) at downtown Sacramento on January 24th which smashed by 5 °F the previous warmest January temperature of 74 °F (23.3 °C) set on January 12, 2009. Records at downtown Sacramento go back to 1877.
I will post a more comprehensive summary of the ‘Great California January Heat Wave’ (the most anomalous temperature event in the U.S. since the March heat wave of 2012) when the warmth has run its course.
KUDOS: Thanks to Rick Thoman at NWS-Fairbanks for much of the Alaskan temperature information and Maximiliano Herrera for the notes on Canada, Greenland, and Iceland.
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