Windy and Wet

A strong pressure gradient across western and northern Alaska has been producing strong southerly winds today, leading to high surf and elevated water levels along the west coast.  The immediate cause of the stormy weather is a low pressure system moving from far eastern Russia into the Chukchi Sea, but equally culpable is the strong high pressure still hanging out to the south of Alaska (as highlighted in recent posts).

Here's a weather map from early this morning:

Webcam photos from Nome and Shaktoolik show agitated seas this afternoon:

Peak wind gusts today were generally in the 40-50mph range on the west coast, but higher in exposed and elevated locations:

The southerly flow has imported large quantities of atmospheric moisture; this process is often termed an "atmospheric river".  Model data suggest that today's precipitable water (i.e. total column water vapor) anomaly is well over 3 standard deviations above normal for the time of year in some areas:

It's no surprise, then, to see that a lot of rain has fallen in the western Brooks Range in the past 2-3 days, and especially today.  Here's a map of 72-hour totals (inches).

The Wulik River gauge near Kivalina shows the impact on water levels just since last night:

Looking southeast toward Fairbanks, the wet weather pattern is now pushing the Upper Chena River to elevated levels, and the forecast shows the river approaching the minor flooding threshold in the next couple of days:

Fairbanks airport has recorded 1.6 inches of rain so far this month, making it the second wettest start to September on record (first 10 days), but of course far more has fallen in the hills (e.g. 5.0" at the Munson Ridge SNOTEL so far this month, and over 8" since mid-August).

The wet pattern is also reflected in the amount of cloud cover Fairbanks has seen so far this month: the greatest on record for the ASOS instrument era (1998-present) for the first 10 days of September.

To round out the statistical summary for September 1-10, daily high temperatures in Fairbanks have been the lowest since 2004, and the difference between daily high and low temperatures has been the smallest since 1990.  All in all, miserably cloudy and damp weather at a time of year that is traditionally thought of as fine and settled after the conclusion of August rains (check out this classic Rick Thoman post from 2013: https://ak-wx.blogspot.com/2013/01/one-more-round-of-interior-alaska.html)

As for the forecast, it looks like there's more of the same until the middle of next week; but then a significant change to drier and cooler weather seems likely as the North Pacific ridge finally weakens.  The latest forecast even suggests a chance of a cold trough dropping down over the state in the fourth week of the month - check out the bottom right panel below, from Google's leading WeatherNext2 AI model (which is substantially better than any other model for forecasts beyond 7-10 days).