As many of you have probably heard by now, a major shot of cold air is on the way for this weekend, with the potential for a storm system to bring the first snowflakes of the season for some areas. For more information on that threat, check out our article we published earlier this afternoon. This article will focus on what’s to come after that blast of cold air.
October is just about complete, and it was a very warm month both nationally and regionally.
It has been much warmer than average for most of the country this month (ACIS).
In predicting the future weather patterns, we often like to take a look at what has happened in the recent past, and roll forward with any expected changes to the pattern, or lack-there-of. Here is the 500mb pattern that has occurred in the Northern Hemisphere this month:
The 500mb pattern this October featured a large trough in the NE Pacific, which largely prevented Arctic intrusions.
The two big features that stand out are the large amount of blocking near the North Pole — particularly the Eurasian side of the Pole, and the large trough in the NE Pacific. The blocking supported a large amount of snow in Eurasia, as the snow cover this year in those regions is among the highest it’s ever been in October. This doesn’t affect our current weather pattern this month so much, but it does lead to the higher probability of a snowy winter.
Read more