October Temperature Contrast

There will be much more to say about this once all the October numbers are in, but there's no doubt that Arctic Alaska and the wider Arctic region have seen extraordinary and record-breaking warmth this month.  The chart below shows the updated season-to-date accumulation of freezing degree days in Barrow: the total is now up to a meager 78 FDDs.  The previous record lowest through this date was 128 FDDs in 2012 (data from 1930-present).

The mean temperature so far this month in Barrow stands at 30.2°F, and with a chance of rain (plain, not freezing) in the forecast, that number isn't going to drop much by the end of the month.  Sea ice is nowhere near Barrow, and the Arctic-wide ice extent is at record low levels.

In contrast, clear skies and light winds in Fairbanks have produced strong inversion conditions as surface temperatures have turned rapidly cooler - we might say winter had a sudden onset this year.  Season-to-date FDDs are now higher than the past 3 years at this date and are close to the long-term normal.