HEAT CRANKS UP TO END THE WEEK...MEMORIAL DAY WEEKEND TO BRING PLENTY OF ENJOYABLE OUTDOOR WEATHER DESPITE PERIODIC SHOWERS LATER IN THE HOLIDAY WEEKEND
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 firstname.lastname@example.org. This blog is for you, so I hope you enjoy it! -Matt Noyes
General Weather Summary:
Hump Day, and focus shifts more squarely on the upcoming weekend as many New Englanders look forward to the first unofficial weekend of summer! The weather in the northeast is always a bit tenuous during the Memorial Day holiday as we're still in the battlezone between lingering Canadian cool and building summer warmth. That same battle will be the focus of the forecast this weekend.
For now, we continue to enjoy relatively dry air, though each passing day brings a bit warmer conditions. After scattered frost across the valleys of Northern and Central New England - and a few patches in the especially sheltered locales of Southern New England - on Tuesday night, Wednesday temperatures once again rebounded quickly with the help of sunshine. Morning clouds were rather stubborn around the Pioneer and Lower Connecticut River Valley, and near Portland, ME, largely a result of cooling air during the overnight, but enough dry air has been present to burn these clouds off. Aloft, middle and high altitude clouds have been spilling south out of Canada and across New England into Wednesday afternoon, the result of warmer air trying to move in aloft and colliding with a lingering cool pool. These clouds will mix with the sunshine Wednesday afternoon, at times providing a milky appearance to the sky, but with cloud bases at 10,000 to 20,000 feet depending on the type of cloud, there will be no chance of precipitation from these clouds. Meanwhile, the center of high pressure here at ground-level that has been responsible for delivering our shot of dry and pleasant air is gradually shifting east. In the process of moving sluggishly off the coastline, the high pressure cell has split into two centers - one just south of Nova Scotia and another south of Georges Bank, southeast of New England. The northern lobe of the expansive fair weather cell is feeding cool air south, then west toward New England, while the southern lobe is pumping warmth northward. Where these two airmasses collide, a swath of fog and low clouds developed east of Georges Bank and has been moving west across the Bank, but is not expected to move onshore or into the near-coastal waters east of Cape Cod. You can monitor this fog and cloud bank through the visible satellite imagery, linked under the Satellite imagery section to the left of this discussion. Elsewhere, an onshore wind will continue to penetrate through most of Maine, keeping our temperatures in the 50s at the coast and 60s inland, while the remainder of New England finds weak sea breezes and a light inland south breeze that will team with sunshine to boost temperatures into the 70s away from cooling coastal breezes.
Expect another quiet night Wednesday night, though with milder air moving in beneath partly cloudy skies, temperatures will hold in the 50s for many areas and drop into the 40s for cooler spots, with frost much less of a concern than its been over the past couple of nights. The exception to the rule will be found from the New Hampshire/Maine coastal border, northeast along the Maine coast and inland for about 30-40 miles, where a light onshore flow will mean cooled, moist air streaming in from the Gulf of Maine, and the result will be plenty of low altitude clouds and fog for these areas early Thursday morning. Though I expect these communities to face a slow start Thursday morning, the remainder of New England will see quickly rebounding temperatures. After a few hours, the coastal plain of Maine will join the ranks of the remainder of New England, burning off clouds and fog in most spots except perhaps far Downeast, and temperatures will soar for one and all. Winds will still be fairly light, but will blow from the southwest around the north side of our fair weather cell - the high pressure center drifting south along the Eastern Seaboard. Though immediate coastal locales are still likely to see a weak sea breeze kicking during Thursday afternoon, the remainder of New England will find pronounced warming as warm summer air that's been building across the Ohio Valley points west, and into the Great Lakes, wraps east into New England. With a westerly component to the wind, downsloping winds will be at work, as well - remember that downsloping occurs when wind flows down the faces of the hilly and mountainous terrain, warming and drying upon its descent.
Perhaps an interesting part of this late-week warmup is that it doesn't occur uniformally through the atmosphere. In fact, with an upper level storm lingering over the Western Atlantic, a pool of cool air will be slow to depart, and a winding, "amplified" jet stream will be slow to push this cool pool away from New England. The result will be a conflict of airmasses several thousand feet above our heads over Maine, where cool air will be hesitant to let go and warmth will be itching to move in, resulting in a band of stubborn clouds Thursday night into Friday for much of the Pine Tree State with periodic showers. Elsewhere, a blend of sun and clouds will begin our Friday, and those areas that start with clouds will quickly come online. Though it's not tremendously common, the position of the high pressure cell over the Southern Mid-Atlantic will encourage a northwest wind, even as deep summer warmth spills across New England. A northwest wind will slope down from the White Mountains and Mountains of Maine, likely making Southern New Hampshire through the coastal plain of Maine the hottest spots in New England, with temperatures surpassing 90 degrees in some of these spots. Elsewhere, temperatures will still soar through the 80s to around 90 degrees, and the drying nature of the northwest wind will mean that while the air feels somewhat humid thanks to the nature of the incoming summer air, it won't will an exceptionally muggy day by any stretch.
By late Friday, a strong jet stream disturbance that's been responsible for repeated thunderstorms across the Plains and Midwest will move east toward New England, towing a weakening cold front at the surface. For the past few days, I've been expecting a round of thunder and perhaps strong thunder with this front for the Northeastern United States, and though that still appears to be the case for Upstate New York, far fewer thunderstorms will develop in New England, as the speed of the front now appears slow enough to delay its arrival until overnight Friday night. Overall, this will mean scattered storms in New York, but only isolated thunder late in the day Friday for New England (mostly in Western areas) with a mainly dry Friday for most of us. Friday evening, some of the strong storms are likely to cross the state lines into Western New England from New York, then scattered showers will mark the passage of the cold front for most of us overnight Friday night.
Behind this front, the air will be cooler, but not cool by any stretch of the imagination. In fact, the new airmass should be dry enough, but mild enough, to bring a fantastic summer-like day to New England on Saturday for the kickoff of our Memorial Day weekend. Though the air will be mild, more moist air will have been thrust southward for the start of the weekend, but will try to return northeast on Sunday. Though there won't be much of a temperature clash with this incoming airmass and the one already in place, the increase in moisture will result in increasing clouds. Eventually, this increase in moisture will breed showers, though my hope is that these showers won't move in until later in the day and will come in scattered form, the timing of this airmass change will determine the exact timing and intensity of any showers later Sunday. By Memorial Day Monday, a following cold front will approach and move through New England, sparking new showers and a chance of thunder, though once again, timing will be critical. At this point, my thinking is that this front will sweep enough moisture through New England Sunday night to allow drier air to bring emerging sunshine after early clouds on Memorial Day.
Technical Discussion: Today has evolved much differently than expected behind the scenes. Not able to get one out today.
Enjoy your Hump Day!