Feb 10, 2016 11:57 PM
NH1 Weather Insider with Joe Joyce: Thursday February 11, 2016
NH1 Chief Meteorologist
Today will feature another round of scattered snow showers, but this time we even may see a few snow squalls. There is a big difference between the two. The snow showers come and go, no big deal. A snow squall can come in and reduce the visibility down to a quarter of a mile, dump a quick inch or two of snow on the ground, and roads can become snow covered with numerous accidents possible. That is a concern for Thursday. What we have to watch is an impressive band of lake effect snow which is coming off of Lake Ontario. The band of snow is moving across the whole state into southern Vermont. Some of this energy may start to push into Southern New Hampshire Thursday, possible during the morning hours. It looks like the best chance of a few of these morning squalls will be in southern New Hampshire. It is not guaranteed to happen, but it is something to watch out for. These squalls could have an impact on the roads between 8 AM and noon time.
A cold front will be pushing off the coast of New England Thursday with breezy WNW winds developing during the afternoon. An upper low will cross through the region which may trigger a few scattered snow showers during the afternoon as well with abundant cloud cover. Highs will be in the 20's. As the upper low pulls away, a more significant shot of cold air will arrive in New Hampshire Thursday night with lows dropping into the single digits. Friday will see a weak ridge of high pressure in place for some morning sunshine. The sun will fade behind increasing afternoon clouds along with the Arctic Front which will push through Friday Night and early Saturday morning. This may come with a few more scattered snow showers.
Once the front pushes through, the door will be open for the coldest air of the winter this weekend. Strong NNW winds will direct in the Arctic Blast with a deep trough in place across the east coast enabling the cold from Canada to spill right into the Northeast, especially New England. Highs on Saturday will be in the teens, and single digits in the mountains and NW valleys. Wind chills will start become quite intense as the winds pick up during the afternoon. I expect wind chills to feel -10 to -20 Saturday afternoon. By Saturday night, most areas will see there temperatures dropping below zero. The NW valleys will see their temperatures dropping to -10 to -15 overnight through the predawn hours of Sunday. Wind chills Sunday morning will feel about -20 to -30 below zero. Mountain summits will be so cold it is not even worth venturing outside in this. On top of Mt Washing ton wind chills will range from -80 to -100. Sunday will see more sunshine, but highs will only be in the single digits and Lwr teens. Record cold will be possible Sunday. Winds will begin to diminish Sunday, so the wind chill will not be a s much of a factor by the afternoon.
Obviously, this cold will be extreme. It is important to watch your pets and limit prolonged exposure outside in these kind of elements. It will be critical to be dressed from head to toe with warm clothing and multiple layers if planning to be outside. It is easy to get frostbite in this kind of Arctic air. Prepared with winter weather gear if you plan on travelling, since you never know what can happen on the roads. This will be a battery killing cold, so don't be surprised if your car does not start this weekend.
But just as quickly as it moves in, the Arctic cold will be lifting out. High pressure builds in for Monday with more sunshine. It will still be cold in the 20's but not as intense as the potential record cold over the weekend with less wind. We will be watching the potential for a coastal storm next Tuesday. The heavy cold air sometimes is slow to retreat so any approaching moisture will be starting as a wintry mix. There are still questions if this will be a cold storm or a milder storm. Some models are taking the storm south of New England for a chance of snow, while one of the better models has the low tracking inland towards the Mid-Atlantic and west of New England. This will mean a better chance of rain. Chance are it will be somewhere in between the two, with a combo if snow, sleet, Ice,and rain at the coast...but it is too early right now for specifics. We will keep an eye on it and keep you informed of any developments as we get closer to the event.