Dec 17, 2015 12:23 AM
NH1 Weather Insider with Joe Joyce: December 17, 2015
NH1 Chief Meteorologist
Thursday morning will start off a bit interesting. Drizzle developed overnight in parts of New Hampshire. Low level cold air is parked across the North country extending down through Carroll, Strafford, and Rockingham counties. A freezing rain advisory in place for Thursday morning where ares of drizzle will be falling on cold surfaces near 32 degrees or below. It is something to watch out for during the early morning hours in these areas with a slow improvement as the morning progresses as warmer air will mix down with SE wind flow at the surface.
Thursday will be a damp day. Drizzle will remain for the morning hours with rain spreading into New Hampshire for the afternoon and evening hours. I expect the heaviest rain from 3 PM until 9 PM. About .25"-.50" of rain should fall. A cold front will be the trigger for the rain which has been directed from the Gulf states right into the Northeast. The rain ends after midnight, but some patchy drizzle could remain overnight. The cold front pushes off shore Friday with drying winds, partly sunny skies and highs in the 40's nearing 50. A wave of low pressure will ride up along this cold front, but the front will be far enough off the coast that I do not think we will see any weather complications from it.
A deep upper level trough will shift into the northeast for the weekend supplying seasonally cooler temperatures for once with highs in the 30's Saturday with chilly blustery NW winds. A mix of sun and building clouds during the afternoon. Enough low level moisture will be in place for clouds to build with heating of the day, as well as the risk of passing flurries and even snow showers in the mountains. This will be a big weekend for ski areas to get the snow making going as obviously mother nature is not delivering the snow quite yet. The colder air will begin to lift out Sunday into Monday with lighter winds under a developing upper level ridge. This will keep dry conditions in place with sunshine Sunday with highs in the Lwr 40's and highs in the 40's near 50 Monday with more of a SW wind developing as high pressure pulls away.
Upper level ridging returns to the east coast for next week with unseasonal warmth building and shifting towards the Northeast. While temperatures are warming, cooler air will be driven down into the Plains which will collide into the Unseasonal warmth. This cold front will be a trigger for more showers and thunderstorms. This along with a steady SW flow aloft tapping into some moisture from the Gulf, we will have to track a few periods of rain into next week, which look most likely in the Wednesday & Thursday time frame.
There are questions regarding the Christmas forecast this far out. It will be warm ahead of Christmas, and there will be times of rain as well. The question is will the mild air hold into Christmas day? Or does the cold front push through and bring in cool drier weather with gusty NW winds instead? Timing issues remain. We are going to have to wait to find a little more model agreement before we start giving out the Christmas day forecast. Too many cooks in the kitchen this far out!
December is running 10 degrees above normal! That is incredible. This could end up being our warmest December on record if this keeps going like this. There are signs of a more typical wintry pattern returning sometime in mid-late January as a ridge builds in western Canada and a more persistent trough settles in across the eastern US. To be continued...