Tuesday, January 3, 2023

Excessive warmth is cancelled for rest of this week and some cold rain Wednesday night is expected to turn to some snow Thursday/Friday

The radar and temperature map Tuesday afternoon is a complete debauchery with a huge area of rain covering much of Pennsylvania and New York while a complete torch-fest rages across the Ohio Valley and Mid-Atlantic. It all appears to be headed in Vermont's direction yet the heaviest rain will actually miss the northern part of the state and the warmth will also stay mainly to the south. It all boils down to a temperature forecast in the short term that isn't nearly as mild as once feared while the snow forecast continues to inch in the right direction. The news isn't all good and I will discuss that later but the outlook continues to look a little brighter for us winter weather lovers over at least the next 10 days. 

Much of that aforementioned rain on Tuesday will try and push north but will weaken as it does so and  will amount to a few hours of light rain during the overnight hours in the MRV. Meanwhile temperatures aren't really expected to move anymore and the large area of warmth over the Mid Atlantic will stay where it is. Readings will more or less stay in the 30's under a blanket of cloudiness that is expected to envelop the region for much of the rest of the week. A second surge of moisture is expected to reach us on Wednesday night in the form of a cold rain but as this is happening, a low level push of cold will be taking shape and by Thursday morning will be very close to bringing us a temperature profile capable of supporting snow. From there questions continue regarding how much moisture can we squeeze out of a disorganized low pressure conglomeration gradually indicated to sag southweastward. Some, I think. Light snow should begin falling Thursday morning with temperature hovering at or just below the freezing mark. The snow Thursday is not expected to be heavy and accumulations will likely be in the 1-3 inch range, but there's an enhanced surface feature that has the potential to bring a 2-5 inch category snow for us on Friday. Though we appear to be in a fairly good position for this additional Friday snow, it's also easy to envision a shift so stay tuned. Thursday also begins a stretch of mostly sub-freezing temperatures that should prevail across the high country for most of next week. I say most for a reason because the pattern isn't cold enough to prevent an above freezing hour here or there during the afternoons, but we seemed to have killed the excessive mild weather for at least a little while. 

Though a lot of mild weather covering Canada with a very weakened polar jet in North America, we do have some split flow in the jet stream with the storminess in the Pacific  moving across the country underneath the ridging which is expected to set up shop in western North America next week. This is a big reason why our temperature outlook is just "mild" relative to average and not "total torch". There are a couple of systems to watch in the Saturday, January 7th time frame to Monday, January 9th but moisture appears to be focused on areas south of us. Though we could use some additional snowfall, we might have to settle for some long awaited sunshine which may show up in a limited way on Saturday and appears more likely Sunday into Monday. A little snow cover might allow temperatures to cool into the teens Sunday and Monday mornings with high temperatures approaching 30 across the high country. As we move through next week, the set up looks interesting with a couple of additional features undercutting the +PNA ridge. One of two features could end up blossoming into a substantial east coast precipitation-maker and a snow producer for interior locations across the northeast. I can't say which one or make guarantees regarding either one, but we will be provided with a few chances. 

Now on to the not so great news. 2 days ago I was largely encouraged by both the short term cooling trend and for the potential to see some arctic air return to the forecast picture later in the month. Ensembles have moved in the wrong direction today mainly because they show a Pacific again growing a bit irritated as we move into the middle part of January. Often times I am at odds with the collection of social media wishcasters who have a habit of downplaying trends or data they don't like or want, but there was some understandable confusion and contradictions about what ensembles are showing and MJO forecasts which continue to show a more favorable set up. Taking the data at face value though, there is no indication that much of Canada will chill down and winter weather will have to come as a result of undercutting storminess while cold air will be in limited supply. I am glad we are in the coldest part of our climatology because we can put it to good use in this pattern.

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