The vortex has returned to the polar region where it belongs. This week has a January thaw-like feel – a warming trend that typically occurs during the third or fourth week in January. We’ll have temperatures approaching 60 for Tuesday and possibly higher temperatures on Friday before a cold front moves through later Friday. Rain late Wednesday through Thursday and possibly into Friday before the frontal boundary passes.
Colder temperatures return for the weekend. Still no snow in sight although the climate models predict a trend towards colder than average temperatures here by mid February into the first week in March. The predicted storm track remains to our west, giving us rain or a mix.
Tuesday 2/5 Followup- The extended range models are beginning to show an active pattern developing next Tuesday and continuing into the President’s Day weekend and beyond.
A cold front will move through this Friday…the front will likely stall and remain to our south, acting as a conduit for southern jet stream moisture to over-run our area early next week. A set up for mixed precipitation – rain, sleet, freezing rain and snow as several separate impulses develop and affect our region.
No large snowstorms showing yet, but things will definitely get more interesting. Stay tuned.
A strong cold front moves through Thursday and cold, high pressure builds in for the weekend. While high pressure usually brings fair, sunny skies, this high pressure system will have embedded vorticities (disturbances, or eddy currents) that may bring periods of clouds with the sun.
There’s even a chance of an occasional snow flurry, especially north of the Philadelphia area. Timing of these fast moving vorticities and cloudy periods is too difficult days in advance.
Temperatures will be cold, with highs Saturday near 30 and highs on Sunday nearer 40.
Another strong cold front moves through Tuesday into Wednesday. Light rain possibly changing to snow is possible. Models don’t show low pressure development at this time, but it’s a possibility.
The unseasonably mild weather pattern we’ve been experiencing appears to be breaking down over the next few days. Monday will be seasonably cold.
With the exception of this Tuesday, temperatures will be colder and closer to average, with even some below average temperatures towards the end of this week. We may even see some light snow Saturday if a storm passing to our south moves further north.
By the end of next week (around the 20th), a large outbreak of cold air is expected to move into the continental US.
The graphic below shows predicted global temperatures (NAVGEM model) now and in 11 days. Notice the colder temperatures at the poles, Siberia and Greenland.
Current Global Temperatures
Predicted Global Temperatures January 16th
This colder air has to go somewhere. Current forecasts show it descending into the US but current predicted configurations will block storms, keeping them to our south. No snowstorms are in the long range forecast.
Two more rain storms forecast for this week –one Thursday (possibly missing us, staying to the south) and on Saturday. The Saturday storm may be a nor’easter, but the lack of cold air makes this an atypical nor’easter for January. It looks like rain!
The current weather pattern is quite anomalous for January. There’s little evidence of deep intrusions of cold air into the continental US for the first two to three weeks of January!
There will be short duration cold air intrusions into the Northeastern US which will alternate with mild air and wet flows from the southwest.
The current climate model forecast captures this nicely:
What we need for winter to return is for the height contours (shown in black) to take the following configuration, (shown in blue.)
Obviously, there would have to be giant changes in the current weather pattern to support my early December climate forecast of significant cold weather and significant precipitation. I’m not very confident about that forecast at this time.
So enjoy the relatively mild weather!
The current long range climate models show colder intrusions around the third to fourth week in January, a time when we usually get the “January Thaw”.