Monday, March 25, 2024

More snow is "possible" Thursday night into Friday as cooler weather pattern expected to prevail through our solar eclipse day of April 8

Deep snow now covers all of the northern Vermont high country and I had anticipated a relatively tranquil more spring-like week including some warm afternoons and not more than one day with some light precipitation. Some of what was described continues to be a part of the current weather picture, but I would describe the outlook as a whole as being cooler and more unsettled and this includes additional chances for snowfall across the mountains. 

The deep snow cover has brought some chilly nights to Vermont. Readings fell to the single numbers Monday morning and are expected to fall into the teens once again early on Tuesday morning before southerly winds power readings back into the 40's in spite of more cloudiness during the ski day.  These clouds will keep readings warmer Tuesday night and also prevent temperatures from rising beyond the 40's on Wednesday as our next storm system begins to take shape. Moisture from this initially disorganized storm will stream northward and bring some occasional light rain to Vermont during the day, before moving eastward toward the coastline Wednesday night. This general outcome has been the consensus expectation for a few days now, but recent models are suggesting that the coastal low pressure center will strengthen more dramatically, attain a negative tilt  and position itself near Cape Cod Thursday night. If this trend continues we will see more rain on Thursday with that rain changing to snowfall Thursday night into Friday. I've yet to see enough conclusive confirmation of this change in the outlook to suggest another significant snowfall is likely, but it certainly has my attention and another elevation sensitive snowfall is certainly a slight possibility before the last full weekend of March. 

The aforementioned last full weekend in March looks cool with sub-freezing nights and only slightly above freezing days on the mountain and this general theme is expected to continue through much of the first full week in April.  The week also appears unsettled with at least one opportunity for mixed precipitation or snow (likely Monday or Tuesday). I see no opportunity through April 5th where readings will climb above 50 on the mountain and several are likely to stay below 40. 

 The time has also come for some early April 8th prognostications. It will be around that time when the focal point for cool, unsettled weather is expected to shift offshore yet there remains some lingering ridging in the Davis Strait region and forcing in the Pacific continues to favor cooler weather in mid-latitude weather more generally. I am pretty convinced that the ski season will be alive and well in the MRV with deep snow pack prevailing above 2,000 feet and more patchy snow cover enduring below that. If we can achieve some northwest flow at jet stream level, a real possibility if we can push the unsettled weather off the coast, we really improve our prospects for a clearer sky.



Thursday, March 21, 2024

Storm to deliver 1-2 feet of powder during the ski day on Saturday

What an incredible week it's been already at Mad River Glen. It's been both productive in the snowfall department and entertaining one to experience as a weather enthusiast. It's a been a warm year and a warm month with temperatures across the state averaging at least 7 above the climatologal average. Snowfall has been especially elevation sensitive throughout the entire year and that trend only amplified both this month and week. Snow showers and squalls continue to dust valley locations with an inch or two and then repeatedly the sun would come out and melt everything down to the bare ground. The mountains have gotten a lot more than a few inches from these snow bursts and very little has melted and the powder pretty deep over a solid base of existing snow. The wintry scenes over the mountains parlay nicely with the anticipation of a big grand finale this Saturday, a storm that appears locked in for the entirety of northern Vermont. Even valley areas will find a hard time avoiding accumulating snow out of this one.

The big ingredient Saturday's storm has which many other events have lacked is cold air. The polar vortex lives in late March and has spent the week chilling in the vicinity of the Hudson Bay. A big southern streamer, still fueled by the weakening El Nino, will be pushing eastward Friday through the lower Mississippi and Tennessee valleys. To the naked eye, it doesn't appear as if the polar and southern branch of the jet stream can come into phase and produce a storm of any significance, yet Vermont will get big snow anyway. Rather then suppress moisture, a polar jet impulse will have the effect of pulling moisture from this storm northward into the cold air and  creating a large area of heavy overrunning snowfall for northern New England and rainfall for southern New England. It all begins in the predawn hours Saturday as steady snow quickly becomes heavy snow and persists throughout the ski day. There's enough warm air above us for some sleet to mix in with the snow from time to time, but enough cold air at the surface to keep the snow consistency powdery on the mountain. Snow should taper off rather abruptly just as it gets dark on Saturday with accumulations of 1-2 feet. I am glad I didn't overthink this one else, I might have written it off a few days ago. Weather can always defy conventional wisdom if given enough opportunities and this one appears to be one of those instances. 

Temperatures should remain in the 20's on the mountain through Saturday and winds are expected to be a modest 10-20 mph. A east to southeast direction has had a history of being a little problematic and this is expected during the morning before winds shift and become northeast then north during the afternoon. This is certainly not a historically strong storm, but we appear to be in a great spot for heavy snowfall. 

Sunshine is expected to return for Sunday and continue into Monday. Sub-freezing temperatures most of Sunday should keep the snow drier across high elevations before milder temperatures Monday afternoon bring on another round of spring conditions. This weather pattern continues to be capable of producing some cold though the focus will shift westward over the middle of the continent and milder temperatures are thus expected to prevail over Vermont for the duration of the week. This means 40's on the mountain every day and the possibility of rain in the middle of the week. Ensembles suggest some colder weather and snowfall could return early in April. 

The upcoming week promises to be the best of the season for us and I hope everyone can enjoy it !


 



Monday, March 18, 2024

Very wintry week with snowfall expected almost every day through Thursday

Winter-like temps and snow showers have returned to the northern Vermont country and I am expecting a very interesting next 3-4 days of weather. It begins rather immediately as a deep layer of instability, not atypical of early Spring, but impressive regardless, establishes itself over the state. The vertical cross section of the lowest 9,000 feet of the Mad River Glen atmosphere is rather magnificent looking  and is inidcating the potential for very heavy snow showers Monday evening and night. We are lacking just a tad on the flow. Mad River Glen snow squall fans such as myself prefer a northwest flow off Lake Champlain the prevailing west to northwest flow favors Smuggs and Stowe, but I expect this deep layer of instablity to work some magic anyway. Intermittent heavy snow Monday evening and night will bring 3-6 inches to the mountains, 1-3 inches to valley areas and potentially more than 6 to the mountains north of Waterbury.

The ski day on Tuesday appears drier and chilly with temperatures hovering in the 20's on the mountain. An approaching clipper system will help stabilize the lower troposphere and also help lower wind speeds from what was a blustery Monday. Snow from this aforementioned clipper will arrive Tuesday evening and fall sporadically and not too heavily through Wednesday morning. We are not on the right side of this clipper system and this will keep snow accumulations in the 1-3 inch range Tuesday night and during the ski day on Wednesday. Once we turn the flow northwesterly later Wednesday, heavier snow showers are again likely and should persist into early Thursday. The depth of the instability doesn't appear quite as impressive as Monday night but the flow is better aligned for MRG and snow totals are certainly capable of exceeding an additional 4 inches (on top of what falls Tuesday night and Wednesday). The incoming airmass late on Wednesday is also quite cold for late March and will bring temperatures into the 15-25 degree range for most of Thursday. It will be dry by Friday morning with more sunshine and with temperatures as low as 5 degrees in few spots. 

Where have you been arctic pattern ? It's here for this week with cold air in place for the upcoming weekend as southern stream moisture tries to converge with a polar impulse. Models are still at odds with whether this can successfully manifest into a big snow producing event though I think a light accumulation of snow Friday night or Saturday is likely while a bigger event remains possible. 

Jet stream configuration and trough axis along with the cold air is expected to shift west after this weekend lowering our prospects for the continuation of winter weather though not eliminating the chances for snowfall entirely. More spring-like temperatures or at least spring-like days have become more likely beginning Monday the 25th and I expect at least two of those in the week beginning that day.

Thursday, March 14, 2024

A two-dose shot of wet snowfall over the next few days across northern Vermont high country

 It has been an especially warm winter in the Great Lakes region. After recording the warmest February on record, the first 14 days of March in Chicago has been warmer than the same period in the historically warm March of 2012. The state of Vermont has also been very mild during this 6-week period, but has not featured that mid-spring warmth that has persistently impacted locations farther west. It's been pretty close however with excessive temperatures often impacting Burlington and locations in the Champlain Valley while failing to make it passed the Long Trail. All of these regions are poised to have a very different outcome than March of 2012 as a different weather pattern will dominate the eastern two thirds of the country for the back half of the month. A mild day or two appears possible during the last 5 days of the month but both colder weather and snowfall should remain a more prevailing part of the outlook until April with the dominating jet stream feature consisting of a omega-like block near the Yukon/AK border.

There are a few chances for some wet snowfall over the next few days. A wave of low pressure passing to our south will spread an area of rainfall over northern Vermont Thursday night. This rain will turn to snow beginning at higher elevations first, but ultimately everyone in the valley will be seeing snowfall by morning. This appears to be a 2-5 inch wet snowfall for the high country ending by late morning with the near freezing temperatures rising to the high 30's during the afternoon. 

Only a few intervals of blue sky can be expected for the weekend, mostly on Saturday. More elevation sensitive snowfall can be expected for Sunday. This time we are on the wrong and warmer side of the impacting low pressure area and though its cold enough to snow above 2000 feet, precipitation will be fairly disorganized and the moderate, accumulating snow will be intermittent across the mountains or falling as mixed precipitation and/or graupel over valley locations. Another 2-4 inches is my first guess with this 2nd event, though to reiterate, this applies only to the mountains and little accumulation can be expected on the valley floor. 

The same section of high country that is expecting some wet snowfall over the coming few days, can expect a 5 day period of below freezing temperatures beginning on Monday. Instability snow showers will accompany the chill late on Monday through most of Tuesday. By Wednesday there are indications that a more significant clipper type feature capable of bringing more substantial and powdery snow to MRG. The snow could be followed by our coldest weather of the month on the mountain with readings potentially staying below 25 both Thursday and Friday and struggling to bet above freezing over the mountains. The reinforcing area of cold late next week should bring the return of some sunshine for at least a day or two. If the strong southern branch storm stays south of New England for the weekend of March 23 and 24th, sunshine will continue and temperatures will moderate. If the storm comes north, that will be a situation certainly worth discussing.

Tuesday, March 12, 2024

Colder weather pattern supports additional snowfall for the VT high country with some spring-like days sprinkled in

The duration of March will feature some sprint-like days, especially over low lying valley areas. That said, winter 2023-2024 isn't done and the weather pattern for the foreseeable future favors several opportunities for additional snowfall and a few multi-day periods of colder weather capable of keeping temperatures below the freezing mark across the mountains. 

Temperatures will drop into the 20's Wednesday morning before one such spring-like period begins with readings climbing into the 40's during the afternoon followed by near 50-degree temperatures Thursday near base areas. Clouds will be more prevalent Thursday as low pressure approaches from the southwest. It will pretty mild when precipitation from this feature arrives from this feature, mild enough for rain or mixed precipitation in valley locations. We are on the colder side of this system however and this means some additional wet snowfall for the high country early Friday. I wouldn't expect a lot, 2-5 inches of pretty gloppy snow, but it does replace my wetter expectations from a few days ago.

It appears as if we are in between weather systems for Saturday, another more spring-like day in valley areas with temperatures in the 40's though it should remain a bit closer to freezing over the high country. A widespread area of colder air will then be pushing south into the Great Lakes region by early Sunday, bringing with it, along with the colder air, an area of precipitation that should impact northern Vermont Sunday. Again, temperatures might not be cold enough to support snowfall in valley areas, but they should be over the mountains and this means more accumulating wet snow. By Monday, colder air will support more powdery snowfall, probably in the form of snow showers. 

This is probably the most favorable upstream environment we've had for sustained wintry weather in Vermont with favorable conditions both in the Pacific and in the Alaska/Yukon area. Most of the week beginning Monday the 18th through Friday, March 22n appears wintry and I think there's some storm potential for late in the week. The favorable weather pattern has to overwhelm an obscene warm weather feedback stemming from a warm Great Lakes aggregate thanks to the sustained torch impacting that region through much of last month. Another big storm late in March is thus certainly not a guarantee but the weather patterns certainly supports this possibility both late next week and beyond the 22nd when more colder late March weather appears likely.

Sunday, March 10, 2024

Over a foot of mostly powdery additional snow expected over the mountains late Sunday into Monday

Heavy wet snow pummeled much the northern Vermont high country Saturday night and early Sunday and with it came the power outages. The wet snow always brings this risk, but it appears especially bad thanks to the fact that snow fell over largely unfrozen ground, leaving many large trees susceptible to an uprooting. Thirteen thousand customers just in Washington County alone according to power outage US.  Hopefully folks impacted by this get electricity back soon including the ski areas which appear to have been affected Sunday morning. With the surface low pressure center tracking west of Boston and over interior New Hampshire and Maine, much of Vermont experienced the expected lull in the storm early Sunday. A deep layer of northwest flow is poised to establish itself over the entire state Sunday afternoon allowing the wrap-around moist conveyor of the storm to bring snow back to the mountains. Snow should be falling lightly late Sunday afternoon and evening and intensify over the mountains even as it remains more intermittent in valley areas. Most importantly, temperatures above 1500 feet will cool into the 20's changing the consistency of the snow to a drier, more powdery variety. Aside from being nicer to ski in, the drier is also a little easier on power lines. Northwest winds are expected to increase Sunday night into Monday even as the snowfall continues. Expect blustery conditions Monday with 20-40 mph winds, temperatures in the 20's and the additional snowfall which should taper off to flurries Monday afternoon or evening. I expect we receive another 2-4 inches Sunday, 6-12 inches of powdery snow Sunday night and an additional 3-6 during the day Monday. This would bring us to a storm total ranging from 20 to 34 inches.

More sunshine, diminishing winds and milder 35-40 degree temperatures can be expected for Tuesday with readings climbing into the 40's across valley locations. Clouds are expected to return for Wednesday but temperatures are expected to climb well into the 40's 

More weather is expected late in the week as low pressure is expected to emerge in the plains and track eastward and eventually somewhere south of Vermont. Cold air is in short supply but a minimal push of cooler temperatures is expected to push south just ahead of any precipitation which keeps us in play for some wet snowfall. The prospects for snow appear better as we get closer to St Patrick's Day thanks to colder air which as I've mentioned in prior posts, appears to want to stick around for the ensuing week. More on that in the next update.

Friday, March 8, 2024

Biggest storm of the season set to hammer MRG with 21-42 inches Saturday night through Monday

Got a real solid update on our powerful winter storm storm incoming. Just a beautiful elevation event for the northern Green Mountains and it really just comes down to sorting through all the particulars which we will try to do in this update. 

Meanwhile, sunshine finally made an appearance and another round of sub-freezing temperatures Friday night should give us a short break from the mud. We've managed to eradicate the excessive warmth for the time being but temperatures are still running above normal and are more typical of the back half of March than the first half. All that said, even the limited amounts of cold appears to be enough to keep this upcoming event snow above 2,000 feet and mostly snow between 1000 - 2000 feet. Clouds from this approaching weather system should arrive just after sunrise Saturday and continue to thicken throughout the ski day. 

I was really encouraged to see data from higher resolution Euro and NAM indicate very robust strengthening of low pressure near the Jersey coast Saturday night. This feature will quickly become the dominant component of this system, consolidating the storm as it tracks just west of Boston on Sunday. With temperatures rising into the 40's across valley areas Saturday and near 40 across the high country, precipitation is likely to start as a mix or rain depending on elevation Saturday evening. Wet bulb readings suggests a quick turn to snow above 2000 feet and a gradual turn to snow above 1000 feet. Very heavy snowfall is indicated on a few simulations early Sunday morning before a potential lull in the storm during the middle part of the day.

Snow consistency appears pretty wet below 3000 feet during the first part of this event. There is a substantial column of boundary level air indicated to be in the 28-33 degree range on model cross sections through midday Sunday. Keep in mind that heavy wet thump snow can both make travel conditions very treacherous and cause power outages, especially when combined with wind.  Conditions begin to change late Sunday as colder air begins to settle across the high country as the flow becomes northwesterly. This is ultimately what will separate this storm from the pack this year as the setup appears outstanding for a continuation of colder snow across the mountains Sunday evening, night and Monday. The flow looks great and the storm will be slow enough to depart to allow lingering moisture to just hammer the northern Greens with continuous cold snow. Here are my expectations on snow totals period by period. Please keep in mind that this is a very elevation sensitive event and if you're reading from the Champlain Valley, your outcome will be very different and considerably less snowy than the one forecasted for the mountains. 

Saturday Night: Mixed precip changing to snow - thump potential toward dawn. 6-12 inches mostly wet snow 

Sunday Day: Heavy snow early, possible lull midday or afternoon. 3-6 inches mostly wet snow 

Sunday Night: Snow occasionally heavy. 6-12 inches of powder 

Monday: Snow or snow showers. Another 6-12 inches ! 

Total storm accumulations by Monday evening: 21-42 inches 

Snow will be out the door by Tuesday and temperatures will moderate approaching 40 degrees at base areas with the help of some sunshine. Stronger doses of sun on Wednesday will boost readings even further. Clouds are expected to return later in the week and there is a risk of light rain or mixed precipitation before cooler conditions return for St Patrick's Day weekend. 

I still like the idea of a colder regime settling that could begin with some snow on St Patrick's Day. More generally however, it looks like we have a return of more wintry conditions by Monday and that should bring the potential for additional snowfall in some form during the week beginning Monday March 18.