First, the cold: there have been a couple of reports of -50°F in the ongoing cold snap across the eastern interior, according to the NWS. The Birch Creek RAWS to the east of Circle Hot Springs reached the negative half-century mark yesterday evening, and the Robertson River co-op observer near Tanacross also measured -50°F this morning.
Also of note, Northway airport made it to -47°F this morning, colder than anything observed last winter.
Down in south-central Alaska, high winds hammered exposed locations throughout the weekend and were still causing big trouble today. The Palmer airport illustrates the extreme wind episode, with wind speeds gusting over 50mph more or less continuously since midnight on Friday night.
Here's a news article:
The peak gust of 85mph on Saturday morning is the highest credible wind gust reported from Palmer, with data back to 1973. Of course the usual caveats apply about changes in wind measurement instrumentation over the decades, and for the chart below I'm only showing results since 1997, when the ASOS platform was commissioned in Palmer. Also, the anemometer was upgraded to a sonic instrument in September 2006.
Prior to this weekend, the highest wind speed was observed in early January 2022, and that wind storm was also driven by a very strong north-south pressure gradient. Compare Saturday afternoon's MSLP and 500mb maps (below) with those from the 2022 event, as documented in the following blog post:
https://ak-wx.blogspot.com/2022/01/mat-su-wind-storm.html
In Saturday's post, I commented that the MSLP difference between Deadhorse and Seward was approaching an all-time record. According to ECMWF AIFS data (very similar to ERA5 reanalysis), the Deadhorse-Seward difference reached 59mb on Saturday afternoon, and the peak 24-hour average exceeded 56mb. Only one event in the ERA5 history (1950-present) had a higher 24-hour mean pressure difference: February 2-3, 1970.
This really has been an extreme event.
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