Welcome to the weather blog - a regular Monday through Friday discussion of the weather! While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants. I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible. You'll find a quick weather synopsis linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net. This blog is for you, so I hope you enjoy it! -Matt Noyes
General Weather Summary:
Reminder: The podcast and written discussion are now being posted separately, for those of you who subscribe to either or both of the feeds to easily decipher between podcasts, issued relatively early in the morning, and the written discussion, which comes around late-morning most days.
A milder spring pattern is ready to take hold of New England, as the deep Canadian cold that's been repetitively diving southward across the Northeast will retreat into Canada, allowing milder air brewing across the Central United States to spill northward, little by little.
For now, our Wednesday is cold but pleasant with the center of a cool and dry area of high pressure drifting directly overhead. High pressure cells typically bring sinking air - unfavorable for cloud production - and light wind near their centers, so with the center of the fair weather cell moving right over us, winds will be near calm for much of Wednesday. This lack of wind also means temperatures will be slow to rise, because very little "mixing" will take place. Normally, even a light wind can help to mix air from aloft with air near the ground, resulting in a warming of the airmass that takes place due to increased atmospheric pressure on parcels of air that sink toward the ground - that is, as an air parcel sinks, it's compacted due to higher pressure near the ground, and by the laws of physics, this increase in pressure is also directly related to an increase in temperature. But with little or no mixing, that means little or no sinking air to warm, and therefore sunshine is the only method to warm the air, which is less effective than one may think! Nonetheless, the virtual lack of wind and abundance of strengthening March sunshine will mean a pleasant day, albeit on the cool side.
Wednesday satellite imagery (linked to at the left of this page) shows a well defined disturbance moving across the Central Great Lakes, and clouds preceding this disturbance across Ontario. The first of these clouds will spread over Northern New England late Wednesday afternoon, and for the remainder of New England Wednesday evening. Radar imagery indicates a mix of rain, sleet and freezing rain falling beneath the heart of this energetic upper level disturbance, and this precipitation will spread across New England from west to east after midnight Wednesday night. Although Wednesday night temperatures will have dropped below freezing during the first half of the night, a steady southwest wind will drive these temperatures upward again, propelling many areas above the freezing mark by the time precipitation arrives. The exception to this will be in Northwestern Worcester County and Eastern Franklin County, MA, through the Monadnock Region and across most of Northern New England. In these locales, enough cold air will hang on at the surface to hold subfreezing temperatures, while warm air aloft will mean raindrops - the recipe for freezing rain. Not much is expected, but even amounts of a few hundreths to between .10 and .20 inches of ice is enough to result in slippery conditions on roadways and walkways Thursday morning.
This disturbance will be fed by warmth and moisture streaming into New England, and even as it passes by and warm air moves in aloft, a battle will continue closer to the ground, where cold air will hang tough and a battle between incoming warmth and stubborn cold will ensue. The result will likely be lots of clouds and areas of fog lingering with a few showers leftover Thursday morning. The biggest question for Thursday is whether we could break through the clouds to bring out sunshine, and the stakes are high because with such a mild airmass in place, just a little bit of sunshine would go a long way. It appears as though lots of clouds will hang tough through most of the day, but a few breaks of sun are probable in Southern New England as dry air moves in aloft - especially from the Massachusetts Turnpike points south - and where the sun comes out, winds will mix down in altitude with gusts to 35 mph from the southwest, further promoting breaks in the overcast. Where the sun does break through, temperatures will warm into the 60s, though most areas from Northern Massachusetts to the Canadian border will see the cloudy results of a presence of snow, retarding the progression of warm air.
Meanwhile, the disturbance that pushed into the West Coast midweek will have broken into two pieces, with one chunk of significant energy diving south across the Southwestern United States - dipping so far south it separates from the storm-steering winds of the jet stream for a time - and the northern chunk of energy racing east across the Northern Tier of the nation, steered by those fast moving jet stream winds. In fact, the trend with this system has been to speed it up, bringing showers back into New England later Thursday and Thursday night, but swinging the front south of even Southern New England for most of Friday, allowing cooler and drier air to drain southward to end our workweek. Though this air would battle back against the spring warmth that will be in place Thursday and Thursday night, it won't be a sudden onslaught of cold, and instead we'd still be likely to find temperatures running above normal regionwide Friday afternoon.
Behind the cold front, shallow cool air - though still probably above normal for this time of the year - will settle south out of Canada for the start of next weekend, and likely stick around through Sunday, though a strong northern stream disturbance will have us on guard for showers, especially later Saturday and Saturday night. Thereafter, the last week of March looks as though it will end on a mild note, as a broad ridge of high pressure crests over the Eastern half of the nation, bringing moderating temperatures that will land above normal to finish the month.
Have a good hump day!
Technical Discussion: None today.
Matt
