The past 12 days or so have been significantly cooler than normal statewide, and southwestern and south-central Alaska have been very chilly and wet, as unusual low pressure has prevailed in the eastern Bering Sea. The 500mb height anomaly over western Alaska in the last two weeks looks remarkably similar to the pattern in May:
Model-derived 850mb temperatures (about 5000 feet above sea level) recently hovered not far above record low levels for the time of year over Bristol Bay; the chart below is taken from the vicinity of Dillingham.
Rainfall has been abundant and locally excessive in southwestern and south-central Alaska:
Remarkably, Anchorage is currently tied in first place for the wettest July on record (data back to 1952), and this is the 4th year out of the last 5 to see more than 4 inches of rain in July - with a long-term median of only about 1.7 inches. In 75 years of data, 4 of the 8 Julys with over 4" of rain have occurred since 2022.
McGrath is close to a record wet July as well, with 5.78" so far versus the 2024 record of 6.16". Bethel's 4.49" so far this month is the highest since before 1930.
The Yentna and Talkeetna rivers are both in flood:
With all the rain and cloud recently, temperatures have trended down rather than up since early June in Anchorage:
Looking ahead, a ridge is now building over eastern Siberia, and that means cold air is dropping south over the state and will be reinforced early next week. The latest ensemble-mean ECMWF forecast for Monday shows very unusual cold over the Brooks Range, perhaps threatening records for the month of July. There will certainly be more snow; the Toolik Lake webcam is already showing patchy snow accumulation this morning.
Here's a lower-atmosphere temperature chart for a central Brooks Range location, with the forecast portion on the right.
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