April rollercoaster begins with elevation snowstorm that came close becoming historic for the season

The last regular update of the winter season includes a classic roller coaster ride of April weather in Vermont. A bit of everything as they say with big swings in temperature and a variety of precipitation types which at times could be falling pretty hard atop both the Vermont high country and the low lying valleys.

I haven't updated in several days but our late week storm that was teased as a potential snow producer is poised to deliver some of those goods. The storm has the capability of becoming that elusive April 2-footer but will fall short of that status but not by much. The chess pieces are well positioned with a nice block in the jet stream over the Northwest Passages (small body of water NE of Hudson Bay) and a closed low  in the jet stream over the Canadian Maritimes often referred to as the 50-50 low. A very strong jet stream impulse will attempt to plunge into this set up and is poised to become a big New England precipitation and snow producer. The maturation of this storm is close to perfection for northern New England as a whole but will belly flop just enough so that the heaviest snow is confined to areas north and east of Vermont (northern Maine mostly). Still, Vermont, especially the high country of Vermont will get several inches of snow.

Precipitation will be mostly rain as it commences Thursday morning but areas above 2500 feet could see a period of heavy wet snow with any intense areas of precipitation. The chances for this should actually increase as the day progresses and the threshold elevation for snow will also drop as we move into the afternoon and evening. The axis of low pressure will pass directly over the state of Vermont and continue to strengthen while pushing east. Much of the state will attain access to the colder conveyor of moisture Thursday evening into early Friday and this means snow pretty much everywhere, even in the low lying valleys. Accumulations by midday Friday could be as much as 10 inches above 2500 feet but will likely be confined to a few gloppy inches or less below 1500 feet (which is where most of us live).  Snow consistency will also be very sensitive to elevation with the possibility of a few powdery inches across the high country as temperatures drop into the 20's early Friday. In low lying areas temperatures are likely to hover near or above the freezing mark Thursday night and much of Friday. This storm reminds me a bit of our late February storm, an event where we overperformed and saw over 15 inches. We are dealing with late season challenges that will make that event difficult to replicate but it would have been a nice way to close out the season hypothetically speaking.

Conditions will be blustery through Friday into Saturday even as the snow tapers off. Temperatures are likely to top out only in the low 40's Saturday but Sunday should be a little tamer with calmer winds and readings up near 50. With a little help from some sunshine Sunday, we could actually do several degrees better than 50 but I am not so sure about such help right now.

It will get interesting early next week and worth watching but not because of snow. The big ridge over Alaska is working its magic and will result in an onslaught of cold and wintry weather across the front range late this weekend. The storm responsible is a big one and will gather a lot of Gulf of Mexico moisture as it travels north and east. A LOT of moisture capitalized. Both heavy rain and wind are possible on Monday across the northeast along with relatively mild though not excessively mild temperatures. In recent years we've had some big spring storms result in power outages and some minor flooding across the state and this appears to be a candidate for both though some changes are still possible. When the rain ends late Monday we could also see a one day surge of in temperatures into the 60's Tuesday. After that, some relative chill returns although the bulk of this will impact the central United States and this airmass will modify somewhat before reaching New England.

The pattern though through April 20th continues to look cold and capable of producing more winter weather. That said, regular blogging activities will come to an end with the next post consisting of a seasonal summary. If some interesting weather comes around, I'll certainly talk about it on twitter some, especially since I can't complain about Mets baseball right now.

Winter could be stirred up from the ashes in a potentially interesting setup late next week

Sunshine late on Tuesday and early on Wednesday was a nice needed break from the succession of cloudy days in northern Vermont. The clouds came back as of late Wednesday and unfortunately they will be with us through at least early Friday. In the short term, I wouldn't describe our upcoming weather as especially exciting or anything I would necessarily wish for but it is unique. There is a terrific weather enthusiast in southern Vermont (@vermonsterWx) who posted a atmospheric sounding, a method of looking at the vertical column of air at a specific location. That sounding illustrated a unique situation where in spite of a northwest wind at the surface, much of the air above us is getting warmer over time. This is happening thanks to a wound up storm system (the one that missed us) that is spinning ferociously offshore while occluding and pumping in some relative warmth from its northern flank. The warm air isn't the only thing being shoved in our direction from this storm, there's moisture that is also expected to impact much of northern New England and will do so via the back door. Most of Thursday will be cloudy and the radar will show rain and snow approaching Vermont from the northeast, the opposite of what we typically see when it comes to approaching weather in New England. This precipitation could fall as some snow for a period during the late afternoon but this will change to rain by nightfall as that aforementioned column of air continues to get warmer. The rain will be sporadic in nature but should continue in that fashion through early Friday.

I am sincerely hoping that we can optimize the stretch of weather between late Friday and Monday. It is all a question on the extent of cloudiness. We are expecting a weak area of high pressure to build over the state beginning late on Friday and an innocuous cold front on Sunday isn't likely to bring any significant rainfall to the state. It would certainly nice if that weak area of high pressure was strong enough to remove most of the clouds. If that were to happen we could see temperatures reach the high 50's Saturday and near 60 on Sunday. I'll hedge a little for now and just suggest some partial sunshine and low to mid 50's for the weekend with little wind.

The early part of next week looks like a continuation of the weather from the weekend. Some limited sunshine, a tolerable amount of wind and temperatures mostly in the 50's during the day. And then it gets interesting. I mean where was this pattern back in January !! The pattern that supported a bottling up of cold across Alaska has vanished and there's some evidence of a blocking ridge (depending on what set of ensembles you are inclined to believe), the EPO looks decidedly negative (relaxed Pacific pattern) and the AO appears neutralized. There are a few different scenarios that could play out given these circumstances but one way or another, a large section of the contiguous U.S. is likely to see a southward push of early spring cold weather. It will assuredly be temporary but it will not lack for excitement. The European operational and ensemble members (and to some degree the GFS ensemble member) showed northern New England taking the brunt of this with a phased storm system impacting us in the middle to later part of next week. It would be a rain to heavy snow scenario that would not be insignificant. Other simulations also indicate the ridging over Alaska but confine most of the excitement to areas out west. From a weather perspective this will be an interesting one to watch. At the very least, we are likely to see a volatile stretch of spring weather starting in the middle of next week that will likely include cold, possibly some snow, a few mild days followed perhaps by more cold.

It's probably worth one or two more blog posts at least.