Climate Watch

Autumn kicks into high gear in September, with rapidly increasing darkness being the most obvious sign of the decreasing heating from the sun at our latitude. Falling temperatures in western Alaska are tempered compared to more inland regions by the moderating effects of the still mild ocean water.

NOAA’s outlook for September favors neither above or below normal overall temperatures. This does not mean that “near normal” is expected. Rather, on balance there’s no reason to change the odds from what we expect just based on the past 30 years. It’s the ultimate “could be warm, could be cool” outlook.

Over the past 114 years temperatures in September have ranged from a high of 71°F in 1979 to 9°F above in 1992 in Nome.

The outlook for rainfall is a different story. After the soggy summer of 2021 (more on that next week), you may be okay with the precipitation outlook, which calls for a slightly increased chance for a drier than normal September. Normal rainfall in September is 2.20 inches, and since 1907 there have only been a handful of Septembers that have received less than half an inch of rain. Most recently that occurred in 2008, when there was only 0.06 inches of rain, by far the driest September on record.

Accumulating snow in Nome in September historically has occurred about one year in three, though more than an inch of snow is much more unusual and last occurred in 2013. Accumulating snow of course is more common in the mountains, especially in the second half of the month. The snowiest September in Nome were the back-to-back years of 1919 and 1920, when there was four inches accumulation.