Saturday, January 7, 2023

Hoping for a little MLK weekend magic but overall pattern remains pretty unfavorable until around January 20th when some signs of a change have emerged

Over the next several days, and hopefully through MLK weekend if we can find some more magic, northern Vermont and the MRV will be able to squeeze some winter out of a lousy early January weather pattern over eastern North America. I can't say I am surprised about a multi-week lousy batting slump given what some of the pre season indicators were suggesting, particularly the La Nina/-PDO combination that continues to prevail over the Pacific Ocean from the equatorial regions to the Bering Sea. I am surprised with the specific evolution of weather events however which included a beautifully blocked setup in December that produced a massive arctic outbreak across the central and southern U.S. right before Christmas and the even faster retreat of arctic air afterwords. That we managed to scour the entire North American continent of arctic air so quickly in the days after Christmas was startling in a La Nina year. Though the Pacific has gotten quite angry as evidence by the freight train of storms pounding California, La Nina winters often feature mild surges of air across the southeast and Mid-Atlantic states with at least some arctic cold remaining in close proximity across Canada. So far this January, Canada has been excessively warm and this is not indicated to change until at least January 20th which has been particularly problematic for us and might prove to be a thorn in our side next weekend when a big east coast storm comes calling. We still have some hope on that sucker however lets not forget about the magic pixie dust MLK weekend can manage to provide. Its been a much friendlier holiday to us than Christmas! 

Some very welcome sunshine, a full day of it on Sunday should feel pretty nice after the succession of cloudy days we've had. Temperatures in the high 20's or low 30's in the valley locations and light winds is pretty tolerable for January as well. Some blue sky should return for Monday though winds will increase some and may push temperatures above the freezing mark in low lying areas during the afternoon. The forecast then looks cooler for Tuesday with the opportunity for some snow showers and then sunshine should return for a good part of Wednesday along with seasonable and sub-freezing temperatures. The airmass restoring some respectability to our current January is more Canadian than arctic and will hold a tenuous grip on New England later in the week as a storm plows eastward toward the Ohio Valley. The track of this storm appears less of a problem than maintaining a supply of cold air throughout the event. Still, interior New England is positioned decently for a front end thump of snow late on Thursday or Friday. There have been consistent indications that this storm undergoes an aggressive maturation along the Mid-Atlantic which would be great if more arctic air was present but the lack thereof leaves even interior sections of New England vulnerable to westward surge of warmth from the Atlantic on the north flank of the storm. It would be wise to expect changes however and important to also note that medium range models do have a propensity to over amplify storms that are more than a week away. A flatter wave does have the potential to yield a mostly wintry weather situation at our latitude. Additionally the flow is split enough that the whole event could simply remain south of Vermont. My biggest fear is the lack of cold air over Canada as the event unfolds and this does keep the door open for a change to rain, even with this seemingly optimal storm trajectory. 

There's some light on the horizon out around January 20-22 with abating conditions in the Pacific and a mildly negative arctic oscillation that should allow colder arctic air to push southward across North America. Until that time however we have to contend with another temper tantrum in the Pacific in the week of January 16th to the 20th with mild weather appearing very likely across all of New England, perhaps strong enough to produce another multi-day thaw, rain and even 50-degree temperatures. We still have some time to avoid that outcome but ensembles have locked on to this signal for several days and above to much above normal temperatures have appeared more and more likely in that time frame. The weather in California in this weather pattern has been relentless and the old adage "when it rains it pours" must somehow stem from California climatology or perhaps the monsoon in India. On this upcoming Tuesday, January 10th, the golden state is expected to get absolutely slammed by jet stream energy capable of producing flooding rains, mudslides and upwards of another 3 feet of snow in Tahoe. Even towns along the lakeshore there have reported a 3-foot snowpack which is unusual below 7000 feet. I might add that in several recent storms it has rained at the lake level yet they still have 3 feet of snow on the ground simply because of the amount of water this weather pattern has unleashed on that region. The destructive aspect of all this is obviously not good but the region has needed the water along with many other states out west.

 


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