To elaborate – The temps will be warming for the Eastern third of the US through the next week or more as we have changes in the pattern. This winter went from a rainy weekends with several Gulf lows to changes starting around December 5th. The cold air in that storm turned the area to snow for many and that was the first of the year. We then oscillated a bit with a rain event and then the big snow on the 18th. After this there were indications that a much colder pattern may arrive around the new year. I was a bit hesitant to be on board completely, but then was convinced we would get cold. The pattern seemed ideal for another snow storm, but ideal atmospheric conditions do not always lead to a storm. So we never had another big snow but a few minor events and the cold came and was reinforced.
Why were we cold? A few factors.
1. The North Atlantic Oscillation (NAO) which features a "Blocking" pattern over Greenland. This block stops cold air from advancing eastward in Canada and instead helps send it into the United states when it is in what is known as its Negative phase (-NAO).
2. What is known as a 50/50 low or similar to it. This is a Low over about 50 degree north Latitude ad 50 degree west longitude.This low at one point was a Polar Vortex (the cause of the big snow) broke down a bit and then was re established with the New England blizzard New Years weekend.
3. The western Ridge or what is known as the Pacific North American (PNA) pattern. This features a High in the western US which sends colder air into the east.
All in all, the above are great for cold air and potential snow patterns.
Another factor with this winter is the moderate El Nino pattern. This has aided in southern storms that were very abundant in moisture. This is what aided in such a wet fall and also the big snow event.
With the breakdown of items 1, 2, and 3 above a change is in the offing and this will mean a much milder pattern for the East. The southern storms will still be forming and thus the pattern returns to where we were before the above colder elements sent us into the chill.
We will likely see a return in a few weeks back to a colder pattern and thus more chances of snow. Until items 1,2, or 3 reappear though, we are likely to see rain, maybe even icing in certain conditions, but not the best chances of snow.
That being said, other factors can make it snow along the East coast (like December 5th which did not really have any of the three above) but it is also less likely they would be pure snow storms.
So warming means a rainy Sunday and a milder next week with temperatures likely to be above normal for some days. Some may even reach the 60s!
All for now!