As we approach November we are beginning to see an acceleration of snowfall over North America with particular emphais over the next 10 days over the cold source regions of Eastern and Western Canada. We are also beginning to see the arrival of snow cover over the Northern Rockies. This is all pretty much normal doings for this time of year. The blue area over the Arctic probably provides a good view of the expanding ice sheet as snow falls on it tend to be light but we can see the ice over the Arctic continuing to recover from the near record melt we saw over the summer and into September.
The jet stream pattern continues to evolve into a more dynamic look especially in the west as we continue to see system after system coming inland. The character of the jet stream in the Eastern U.S. continues to be dominated by ridge/trough ridge trough pattern as deep troughs continue to progress to the east. We have yet to see any sort of lock down of the pattern that holds for a longer period of time.
When you watch the jet stream in motion you can see the continuing changes that take place in the flow. Upper Air winds are not a static feature but are constantly evolving and changing. You can also see how ridges and troughs develop strengthen and weaken over time. The ridge wanting to build in the east remains persistant. This is not a good overall pattern for cold and snow. Cold air comes down aswE the troughs move into and through the east but without anything to hold systems in place, the cold air is fleeting as it holds for a day or two and then moves out. Forecasts for more blocking to develop show up on model runs at least once a day however until we see some sort of consistency in model runs, we have to continue to believe that the current set up will be a dominant pattern for awhile longer.
The marching of Pacific systems into the western states at least affords chances for precipitation events to begin putting a dent into the drought pattern. If you look at the system that comes after the one for Wednesday, the trough lifts up and weakens as it moves east because of the strong dominant ridge. We will continue of course to watch and see how this all evolves. Right now it appears the el nino continues to hold the upper hand in driving the overall pattern across the Pacific and North America.
Check the short range forecast and also see Joestradamus’s piece last night on Siberia snow cover and El Nino. And of course if you don’t have the app for my specific forecasts for the local area of NY NJ PA & CT you can download it for free for I Phone or Android.