A Full Plate
Yesterday was a study of contrast from one part of New England to another. Accumulating wet snow north and west of Boston early in the day gave way to heavy rain at times while it snowed all day near and north of a Brattleboro,VT/Concord, NH/Kennebunk, ME line. Meantime, the warm front stalled out across southern CT, northern RI across central Bristol County and central Plymouth County. South of that axis, it warmed up to 47-54 degrees with southerly gales up to 65 mph in gusts! North of the axis, there was practically little wind from the northeast to north and the temperatures failed to rise above the middle 30s to lower 40s with the all-snow region holding near 30-33 degrees. Then the snow line retreated and collapsed southward across the Boston area and all the way down to the South Coast and the Cape later in the day. The all-snow zone received 7-14 inches which included almost all of the northern ski resorts. Today's weather was more uniform across New England as more and more clouds at various levels showed up through the day. With the exception of northern VT, northern NH and central and northern ME, most of the high temperatures were in the 30s with southern New England in the 34-39 range which is slightly below the average for late February. Boston's max of 37 degrees occurred at 3:50pm. I guess that's about enough time spent on hindcasting. I like it because the accuracy is usually close to 100%. LOL. Anyway, let us move on to the nitty-gritty of forecasting.
That cold front way up north is settling slowly south and will provide a focusing boundary for extra convergence later tonight into tomorrow morning as a weak clipper arrives from the Great Lakes. Its center will scoot along the boundary across northern CT, RI and southeastern MA. I anticipate the swath of heaviest snow to set up in a ribbon north of the Mass Pike and probably closer to Rt.2 extending up into southern VT, southern NH and southern ME. In this belt, more than 3" is likely with some totals perhaps closer to 4-5 inches in that colder air where the snow is fluffier. I predict near or just under 2" along the Mass Pike including Boston with closer to an inch near the boundary and less than an inch south of the frontal boundary. From the Lakes Region northward, 3 inches or less is the expectation. The ETA of the snowfall is around 9pm in the Berkshires to just after 11pm in northern Worcester County with an expansion across the region after midnight. The bulk of the accumulation will be completed by 10am. Thereafter, lingering low level moisture trapped in the region will produce occasional to periodic light snow or snizzle or drizzle through the afternoon into tomorrow night. There will be a light northeasterly breeze with highs in the upper 20s well north to middle 30s elsewhere. As all of this is happening, a storm over the southwestern U.S. will reorganize in the Plains States in the next 36 hours. Feeding on warm air over the Southern States and tapping some moisture from the Gulf of Mexico, the storm and its available atmospheric dynamics will track into the Midwest and head toward the Northeast. Its projected inland path ensures a rain event penetrating much farther north this time. An early arrival of precipitation Monday morning could mean a brief period of wet snow and rain north and west of Boston but little or no accumulation should occur south of Manchester, NH. It is possible that it may only mix with rain or stay all snow from Sugarbush to Bretton Woods to Sunday River. The warm frontal boundary will trek up to at least northern MA so this will be a warmer storm for the Boston area north and west with highs in the middle 40s to near 50. The warm sector southerly wind will not match the magnitude of yesterday's gales on the South Coast and Cape. One wave of low pressure will pass north of Boston and cross the Gulf of Maine Monday afternoon. A second wave should pass south of the region late in the afternoon or evening with its parcel of rainfall passing over southeastern MA only. I do not expect a switch back to snow everywhere on the back end of this storm. The rainfall will also not match yesterday's amounts of 1.4-2.4 inches. It will be more showery and nature and could include some spotty lightning and thunder in southern New England.
Looking ahead, a zone of high pressure will push into the Northeast on Tuesday so expect gusty winds in the morning with plentiful sunshine all day and highs near 40 degrees. The ridge will shift offshore enabling an increasing southwesterly wind on Wednesday ahead of an approaching strong cold front. With some morning sunshine, it should easily warm up to at least 45 before clouds rush in leading to perhaps a squall line of rain and snow and possible lightning. There is a potent upper level short wave which will trigger this action associated with the large temperature change. With the frontal passage early in the evening, any squalls to flurries will end and a chunk of chilly air will rush out of eastern Canada dropping the temperatures to the teens to lower 20s Wednesday night. Thursday will be bright and sunny, windy and much colder with highs near 32. A sprawling high pressure system will exit south central Canada and pass over New England late Thursday night through Friday resulting in light wind. As the high shifts offshore, milder air will move in later Friday into next weekend with spotty showers possible. Long-range guidance indicates a deepening trough of low pressure approaching the eastern seaboard late next weekend. It will become supersaturated and capable of releasing a swath of heavy rain. It is way too premature to accurately extrapolate this action into New England. For what it's worth right now, the more reliable Euro model delays its arrival until after next weekend.
For the alpine and nordic skiers, boarders and snowmobilers, yesterday's fresh snowfall up north has added some extra depth to the established base. Most trails are in great shape being tracked and groomed. Tomorrow morning's new 3 up to 5 inches will be fluffier so plan to get out there early for some fresh tracks. It should be sweet! The NH school vacation week is starting so the rain may put a damper on activities Monday but with waterproof gear, you can have a grand time on the slopes with less people if it isn't torrential rain. Keep your fingers crossed that the far northern mountains stay in the snow zone. Stay in control, be safe and please be courteous on the trails.
Joe Joyce delivers his latest AccuWeather Forecast in tomorrow morning's episode and I shall return later in the day.
Enjoy the rest of the weekend.
