The much anticipated nor’easter has developed over the waters south of New England and will continue strengthening over the next 24 hours. This storm center is fueled by all the classic ingredients for storm development: atmospheric energy provided by the jet stream winds aloft, cool air surging south from Canada and warmth over the Gulf Stream waters of the Western Atlantic. The clash of temperature, combined with the available energy, nis allowing the developing storm center to our south to gain footing and we’ve seen both the cloud structure and wind pattern becoming more organized through the day on Thursday. The cool air pushing south out of Canada means business, however, and is also dry by nature, pushing back effectively against the southern surge of moisture and making any northward progress of rain very slow Thursday. In fact, while our First Alert Weather Team expects showers to trudge north to the New Hampshire border by evening, anywhere farther north than Manchester, NH, will stay much drier – and for some, entirely dry – over the coming days. While a dry forecast for the North Country bodes wonderfully for the all-important foliage-oriented tourism weekend of Columbus Day, with only a gusty breeze to dislodge some of the peak color foliage but no leaf-stripping rain, it’s a different story for Southern New England. After a slow ramp-up in rain and wind Wednesday, late Wednesday evening through the overnight expect northeast gusts to exceed 40 mph on Cape Cod, and isolated power outages are possible by daybreak. The impactful wind – and heaviest rain – are expected throughout the day Thursday into Friday. Thursday’s wind gusts should exceed 60 mph on the Outer Cape and exceed 50 mph along the Eastern MA coast, with 40 mph gusts reaching very far inland across Southern New England, all contributing to scattered power outages. Additionally, heavy rain to the tune of two to four inches with localized amounts over half a foot possible not only will cause pockets of flooding, particularly when combined with falling leaves clogging storm drains, but also will soften the ground enough so uprooted trees are a possibility in strong wind gusts. While the most intense rain and wind is expected Thursday, Friday surely will deliver a wind-whipped rain again, and some new power outages will be possible. At the coast, the persistent onshore wind will build seas to 20 feet, meaning beach erosion will be a concern and coastal flooding is a possibility at the roughly midday high tide Thursday, Friday and perhaps Saturday. While the storm will be much weaker Saturday, the onshore wind will continue and likely will deliver areas of steady drizzle and light rain. The wind finally shifts Sunday, affording sunshine for the final two days of the holiday weekend and temperatures returning to the 60s in our exclusive First Alert 10-day forecast.
There’s no question we’ve entered a weather pattern more typical of October in New England: dramatic swings in temperature, plenty of wind moving the air changes and an increased chance of clouds and showers. Monday’s gusty wind from the south and southwest will exceed 40 mph in a few spots, proving to be just strong enough for isolated power outages in Central and Southern New England but for most of us the biggest impact of the wind will be to keep warmth in place: highs in the 70s Monday. Sprinkles off and on Monday will mean a mostly dry day in Southern New England, though Northern and Central New England see rain ahead of an approaching cold front that eventually delivers rain, perhaps a rumble of thunder and patchy fog for all of New England overnight Monday night. An early morning shower departs Tuesday for a dry day, though clouds will slowly thin so sun should certainly be mixed with clouds, particularly in Southern New England. From Wednesday onward, our attention turns to a large storm center stalling south of New England, over the coastal waters off the Mid-Atlantic. The swirling storm south of us is important because the counter-clockwise flow of air around its center ensures an onshore, easterly wind direction for the middle and end of the week here at home, and this guarantees cool and breezy conditions. Of course, the storm will be producing rain and showers, as well, and here in New England we believe the Southern half of our six-state region has the highest chance of seeing showers cropping up Wednesday through week’s end…and quite possibly into the weekend, depending upon the exact position and strength of that storm to our south. By late weekend and certainly early next week, we’ll see some drier weather nudging in for some improvement in our exclusive First Alert 10-day forecast.
For winter sports enthusiasts, in particular, the first snow of the season is always exciting. Thursday brought snowflakes to the summit of Vermont’s Stowe Mountain Resort, and those flakes migrated east overnight into Friday morning, dropping the first wet, sloppy accumulation of the season at the summits of Sugarloaf and Sunday River Resort. This snow fell on the northern fringe of a storm center rippling along a slowly southward settling cold front that delivered rain showers to the rest of New England, along with a wind shift to open northerly winds from Canada, funneling colder air southward. The new, chilly air is also dry air, so after some big, bubbling, puffy clouds develop with the arrival of the new air this afternoon and create some sprinkles and light showers in Eastern New England during the early and middle afternoon, we’ll find clearing sky Friday evening for a clear overnight. With a clear sky and such cool air, even a light breeze from the north will likely not be sufficient to stop frost from developing in valleys, where the wind will quiet a bit after midnight and temperatures will land between 30 and 35 degrees. Saturday morning frost will melt away but a chill will remain in the air with highs not reaching 60 degrees in most New England communities, though full sunshine and a very light wind at least will mean we make the most out of every degree with the warmth of the sun and lack of wind chill. Milder air makes a return Sunday, though the colliding air will create lots of clouds after early morning sun and the strengthening wind will also add a chill, meaning while the thermometer will add about 5-10 degrees over Saturday, the air may actually feel pretty similar. Showers will likely crop up from northwest to southeast across New England late Sunday into Monday, respectively, with some showers lasting all the way into Tuesday morning before another shot of cool and dry fall air settles in for midweek. The end of our exclusive First Alert 10-day forecast suggests some showers are possible next weekend with highs around 60.