Damp and Dull

Reader Gary commented on the damp and cloudy conditions in Fairbanks this autumn, with frequent light precipitation.  The data bears this out, and in fact the number of wet days has been considerably higher than normal back to July:

With abundant cloud cover and above-normal humidity, the range between daily maximum and minimum temperatures has been smaller than usual:

The reason for this unusual state of affairs is that the upper-level circulation has involved stronger westerly and southwesterly flow than normal, extending from the Aleutians to western and northern Alaska.  And that in turn can likely be traced to the exceptional warmth in the North Pacific, which has developed in connection with a mid-latitude ridge of high pressure that itself fosters stronger westerly flow to the north.

Here are "departure from normal" maps of the 250mb wind vector and the 500mb height (pressure) since July 1st:

On another note, Fairbanks at last reached 32°F yesterday during steady snowfall, and that ties the record for latest first freeze, which was set only last year.

It's quite interesting that the first freeze occurred not on a clear, calm night but with overcast skies and snow.  When I have a chance, I'll look back to see if/when that has happened before; it's certainly very unusual.