We have a strange Nor’ Easter set-up that will dominate the weather this week across the region. We first outlined this threat 6 days ago on Twitter (@SWCTWeather), mentioning the likelihood that one of our three main weather models which did not have the storm was wrong, and that the two that did show it were accurate. As we can see now, this was the correct call, as a closer upper level low will move just east of us after stacking with a surface low pressure system offshore and pulling that low pressure system further west and closer to the coast, bringing with it rainy and windy conditions for all of New Haven, Fairfield, and Westchester county. This post will look to just briefly break down the expected impacts that can be felt on a day-by-day basis with this very slow-moving storm.
Tuesday: We already start seeing the first signs of a forming Nor’ Easter across the region. Look for cloudy skies in the morning with scattered showers and drizzle in the afternoon. It will be moderately humid with temperatures generally getting into the mid 60s across the region. We don’t expect any real accumulating rainfall, just generally cloudy skies with scattered showers in the afternoon as the low pressure system starts to begin to get organized. Even into the night nothing more than drizzle or the occasional scattered shower are expected.
Wednesday: Cloudy skies generally in the morning with scattered showers and drizzle again throughout the day. The low pressure center will continue to get more organized offshore throughout this time, but throughout the day should not be producing much rainfall across the area. Through the evening it is unlikely we have accumulated even more than a tenth or maybe a quarter of an inch of rainfall. It will be gloomy, and by the afternoon and especially evening we will see winds begin to pick up a little bit so that gusts are noticeable (maybe 20 mph or so) but still not much significant. It is overnight, though, that the real impacts may begin to be felt across the region. As the low pressure center forms offshore and then retrogrades back to the west closer into us, there will be multiple pockets of very heavy rain (half an inch per hour for multiple hours and the like) that will move across the entire region. Weather modeling guidance has the first move through Wednesday night moving from east to west, so first hitting New Haven county, then Fairfield, and then Westchester, ending early Thursday morning. Temperatures in the mid 50s during the day on Wednesday will drop into the 40s during the rain Wednesday night as northerly winds take over and the Nor’ Easter continues to strengthen, hitting their peak. With the storm not strengthening too rapidly, though, winds should not bring with them many impacts other than occasional gusts in the 20-30 mph range Wednesday night before they die down on Thursday.
Thursday: Impacts will reach their peak overnight Wednesday night into Thursday, with heavy rain remaining around the region during the day on Thursday. At this time, however, most weather model guidance shows that the heaviest, potentially flooding rain all remain to the north of the region in northern Connecticut and up further into New England, meaning we should be spared the worst. Still, we could get stuck in another heavy plume of retrograding moisture (retrograding meaning moving east to west here) during the morning. If current modeling is correct, though, we should see the rain die down in the afternoon so that we are looking at only scattered showers and drizzle later in the afternoon and into the evening as winds almost entirely die down. With any winds and the overall flow coming from the north due to the Nor’ Easter orientation, temperatures across the entire region will struggle to get out of the 40s, maybe hitting 50 in isolated locations. Overnight, temperatures will stay in the upper 40s as the flow subsides and scattered showers and drizzle move on out.
Friday: By Friday morning, the storm system will be pulling away, and any lingering showers will be gone by afternoon. There should be clearing before evening, with a chance of sun and temperatures hitting 60 degrees before the day is over. Overnight, temperatures will then drop back into the mid to upper 40s, but the storm will be on its way out and actually pave the way for a decent weekend with partly cloudy skies and temperatures in the upper 50s to lower 60s across the entire region.
Impact Summary: Rainfall of a little over an inch. We expect around 1-1.5+ (more north, less south) inches in New Haven county, with .75-1.25+ inches in Fairfield County (again, more north and less south and east, with some pockets of heavier rain possible), and as little as .66-1 inch across Westchester County, as the heavier rain is focused further north and east than that part of New York State. Wind gusts up to 30 mph are possible, but again no serious impacts there are expected. Few other impacts are expected than prolonged cold and gloominess and some isolated flash flooding possibilities Wednesday night into early Thursday as the heavier rain pockets move onshore. River flooding will also be a possibility as much heavier rain gets focused even further north.
So that’s a day-by-day overview of the upcoming Nor’ Easter for the region. As confidence is quite high with the storm, there doesn’t seem to be as much need here for a technical discussion. A reminder that on November 1st we will be launching both consistent free blog posts and forecast updates here on the free site alongside a Premium site, where for a low competitive monthly fee you can view additional forecasting content, technical discussions of weather models and the winter climate, and even see some potential investment analysis we provide of temperature anomaly forecasts across the nation impacting commodity pricing. Free blogs like this will continue to be provided through the winter, though maybe not quite as in-depth, but the subscription site will be more hyper-local, breaking the weather down by county, focusing on storms further out, and offering additional sidebar content. We look forward to the roll-out of all of this additional content for those interested, and we also look forward to continuing to offer the high-quality free forecasting that has allowed SWCTWeather to become so well known over the last few years.