Decouple

Lebanon was down to 7 degrees as of 11pm. Gotta love that fresh snow cover, along with a clear, calm night. The inversion has already set up, with single numbers down at the CT valley and mid teens around 800-1000 feet. The forecast was for a low of 12, but common sense and experience with a clear, calm night would point to a colder than expected forecast. I wouldn't be surprised if the airport dips below zero.

Very complex forecast on the way. And don't be shocked if there is a little glaze late Monday night or first thing Tuesday morning. Not much is being said about it, so those are the ones that always bite us in the ass.

But there is a bit of a squeeze play. We're out ahead of a warm front, and temperatures will warm up a lot tomorrow, with a southerly flow. Since Lebanon is in a north-south valley, the warm air can really work in on a south wind, and that will probably happen. Sunshine will be hard to come by, especially in the afternoon, but since its March, low 40s are not out of the question. The high temps are important for tomorrow night, because if we get warm enough, it will help to cut back the risk of freezing drizzle when precipitation moves in. Since winds should be south or southwest, I don't expect much of a problem for freezing rain, but because ground temperatures are very cold (we had -24 night last week, and near 0 tonight), there is a possibility that untreated surfaces could be slick Monday night and first thing Tuesday morning. A couple weeks ago (can't remember the day, we had freezing rain at a temperature of 36 degrees because the ground was subfreezing, so it can happen. Anything untreated was a skating rink, until temperatures rose to the low 40s, when the icing was alleviated. Ice mainly formed on sidewalks, roads, and the lower part of tree trunks...point being, anything closest to the surface, where the temperature was coldest.

Out ahead of the cold front Tuesday, we should rise into the upper 30s to near 40, along with some rain, but then the front will move through and temps will drop. And that sets the stage for the next storm...Tuesday night into Wednesday.

Lots of details to iron out, looking at a couple of different computer models face value...the warm one has us getting a lot of sleet, then some freezing rain and then rain. The colder storm has us getting a pretty serious sleet and freezing rain (glaze) storm. Ice storms are very difficult to figure out around here, but both models give elevated areas above 1000 feet a serious ice storm, with a possible borderline nasty ice storm in the CT valley. The wildcard appears to be a SE wind that will take over, and almost certainly warm up our temperatures toward Wednesday morning. It also means shadowing, so less precipitation locally...another thing to look at.

Again, we're in a north-south valley, so warm air will have no problem getting in here on a south or southeast wind. It all depends on how well the cold air settles down into the valley during the day Tuesday. Lots to figure out. But the potential is there. Some things that appear to be likely...somewhere in the northeast....

1) Heavy precipitation
2) Potential serious ice storm where it stays freezing rain, probably elevated areas above 1000 ft
3) Another decent hit of snow for the Green and White Mtns, and Longfellow Mtns of ME The rich keep getting richer. Backcountry weather conditions show up to 85 inches of snow at the stake in the White Mtns.

NWS thinks the storm will be colder, because of the cold air locked to the north. I don't necessarily agree for a few reasons...

1)Its March. Tougher and tougher to get cold storms, unless they're classic nor'easters.
2) Seasonal trend. Almost every storm was been warmer, and further north than forecast. Plus, most storms have developed late, and Lebanon has missed out on the heavy precipitation.
3) Climatology. Southeast wind in Lebanon is a kiss of death. We get shadowed and a north south valley warm air pumps in.

Hopefully I'll have a better idea tomorrow.

Edit, down to 3 in Lebanon. We'll be below zero tonight, thats almost a given.