Saturday, April 19, 2014
Another cold night and some more snow on the way. This winter isn't even a third over and some of you have already had enough. If you are not aware, there is the potential for a snowstorm Thursday night and Friday. This storm could end up being a southern Maine or southern New England event, but it does have some potential. I will be updating the forecast throughout the next few days as more information becomes available to me. Here is what I know so far.
Snow or rain?
This is going to be a cold storm, so nearly everyone, even the coast, will see all snow from this system.
Fluffy or sticky?
The snow is going to be super light and fluffy. It will be blown around by the wind and pile up easily because it is so light. This will be a snow you can push away with a broom, but if we get a lot, it will have to be a big broom.
What about coastal flooding?
Throughout each month the height of the high tide changes. You have no doubt noticed in the summer, the seaweed line of the previous day's high tide isn't always the same. Sometimes the high water mark can vary three feet or more over a given month. The high tide Friday at noon is over 12 feet, nearly 3 feet higher than the one today. If the storm did become very intense, flooding would be an issue. I will know more about the intensity Wednesday.
When does the snow start?
There could be a few flurries Tuesday, but those aren't related to the storm. On Thursday I expect some flurries or light snow to break out during the day. This won't amount to very much by dark. The bulk of the accumulating snow falls Thursday overnight and early Friday. I expect the storm to be over sometime Friday morning. Keeping in mind this timetable could be moved forward or back 6 hours.
How much snow?
This is of course the big question. When I look at making snowfall predictions I look at how much moisture the storm is expected to bring. Then I have to think about the weight of the snow coming from the moisture. A storm with say one inch of liquid moisture could leave 10 inches of snow if it's 32 degrees and nearly 20 inches if it's 16 degrees. We are going to be closer to the 16F degree reading so it won't take much moisture to give us over 6 inches of snow.
The track of the storm is critical as the heaviest snow falls on the northwest (upper left) corner of a storm. If the storm is too far away, that corner ends up over the ocean, if it's too close, that corner hits New York or Chicago.
Could this miss us?
It’s unlikely we won't get any snow, but it's not necessarily going to be a foot or more either. Making a definitive prediction days ahead in time isn't possible. There will be a storm, it's the track I just can't tell you yet. One model did have the storm going out to sea while another gives us a blockbuster storm. Still too many unknowns. I am leaning towards this not being a major snowstorm for most of Maine
I have a flight out of the Jetport should I change it?
I have gotten many questions about travel Thursday and Friday. Past experience shows if this is going to be a big storm they will try to not have flights arriving Thursday night so equipment is not stuck here Friday. If the storm ends up big, then Friday would be the day most impacted. Flights will likely be close to normal for the first part of Thursday, with the caveat the airlines hate having planes stuck here. So sometimes they cancel well before the actual storm. If you want to be 100% safe, avoid travel the second part of Thursday and Friday. Again, remember, this is based on a Monday forecast and what ultimately happens could be really different. Airports like Logan and LaGuardia will be impacted more.
What about the roads?
As it looks now, the Thursday morning commute will be fine, the evening commute may see some snow, but not much. The Friday commutes will be more difficult as there would be many inches of snow on the ground.
When will you know more?
There are two major computer runs each day the American models come in first then the European. I get significant new information from each around 10 p.m. and 2 a.m. and again at 10 a.m. and 2 p.m. This means the forecast can dramatically change twice each day. I usually won't update the forecast significantly until I see both models.
How about the next two days?
For New Year's Eve and New Year's Day the weather just looks dry and cold, but not record breaking cold. Winds will be gusty Tuesday evening so be sure to wear the heavy stuff if you are going to be outside for very long.
That's my latest thinking on the storm. An important update tomorrow and I will be tweeting other thoughts about the storm on Twitter @growingwisdomTweet
David Epstein has been a meteorologist for more than 25 years. He spent 16 years in Boston and currently freelances at WGME13 in Portland.
In 2006, David founded GrowingWisdom.com, a business producing educational and marketing videos for the green industry. He currently is a professor at Framingham State College, teaches Jan Plan at Colby College and owns Bloomscapes Inc., a landscape design business.
David authored "Gardens Of New England" and his work has been published in Grolier's Science Annual for 10 years. He lives in South Natick, Mass., and has a summer home in Harpswell.