Western/central US cold and accumulating snow
Record-breaking cold invaded the western US early in the week and has since spread into the central part of the nation. Many spots in the western and central US have experienced daily record low temperatures over the past few days and, in some cases, the all-time low temperature for October was recorded (e.g., Merced, CA, Garden City, KS, San Luis Obispo, CA, Rock Springs, WY, Jackson Hole, WY and Vernal, UT).
Perhaps the most amazing temperature recorded in this unusual cold spell for the western US took place earlier today in the remote observing station of Peter Sinks, Utah. Peter Sinks is a natural sinkhole in the northern part of Utah at an elevation of around 8000 feet and is known for its highly localized effects. Nonetheless, the unofficial overnight low temperature there of -43.6 ºF is pretty amazing for this time of year and perhaps the lowest temperature ever recorded in the Lower 48 during the month of October. Nearby Salt Lake City, Utah provided some supporting evidence of the extreme cold as it set a low temperature record of 14 ºF for the date and records there go all the way back to 1874.
Accumulating snow has accompanied the extreme cold in the western and central states with in such hard-hit areas as the Rocky Mountain States and central/northern Plains. Denver, Colorado has now been hit by two snowstorms this month and is on pace for one of the snowiest Octobers there in around 50 years. The low temperature in Denver this morning was 3 ºF which came within five degrees of the all-time October low of -2 ºF set in 1917. Temperatures tomorrow morning could come even closer to the all-time October low with lows near zero quite likely.