In the midst of a dry weather pattern, the ocean plays a big role in our daily forecast, from rip currents to daytime temperature. Tropical Storm Arthur has become non-tropical well south of New England but the waves churned by Arthur continue to spread north, with Wednesday morning buoy reports south of New England indicating 8 to 13 foot seas. On our New England waters, seas will be three to six feet in swell, creating rip currents along south facing coasts Wednesday, easing to three to five feet Thursday. Of course, with cool ocean water temperatures either side of 50 degrees, any time the wind blows off the ocean, our coastal communities will be noticeably cooler than inland counterparts, and Wednesday is a great example of this phenomenon with a prevailing light easterly wind – the result being high temperatures near 60 at the coast versus 65 to 70 degrees inland Wednesday afternoon. Clear sky and a light wind will allow temperatures to cool to either side of 40 degrees Wednesday night, but a wind shift to blow from the south Thursday will allow even eastern coastal locales to warm into the 70s, with 80s by Friday – the only exceptions being those communities where a south wind blows across ocean water, particularly near the South Coast. All the while, a very high pollen count – likely peaking for the season over the coming week or so – continues, and the sun angle has increased enough for the UV index to reach very high levels, meaning sunscreen is increasingly important for kids and adults. The dry stretch of weather will continue to nudge the brush fire danger higher, as well, usually lowering this time of year as leaves blossom, but without rain, the ground and brush continue to dry out. There’s a slight chance of showers Saturday – only about 15-20% with the more likely result being just increased clouds for the Southern half of New England – as a piece of energy ejects northeast from the storm that’s been stalled well southwest of us most of this week, creating flooding rain from the Great Lakes to the Appalachian Mountains. Any Saturday showers, if they even materialize, would be fairly light and affecting only Southern New England…gone by Sunday. Again, with wind direction the key, an onshore wind Saturday and Sunday will mean Friday’s 80s take a break through Memorial Day, but 80s return to the forecast for a summery, several day stretch starting Tuesday and lasting through the end of our exclusive First Alert 10-day forecast.
New England is entering an epic spring stretch in one of the best looking 10-day forecasts in recent memory. There are a few major weather features near the Eastern United States: a storm over the Great Lakes responsible for Monday tornadoes in Ohio, Tropical Storm Arthur moving east-northeast after brushing North Carolina’s Outer Banks, and a large high pressure – fair weather – dome over Atlantic Canada. The biggest player of these in New England’s weather forecast is, far and away, the high pressure dome of dry air, firmly anchored just to the northeast of New England and keeping the two nearby storms at bay. Just because we see no direct impact of the nearby storms doesn’t mean we won’t see any impact at all: Tuesday midday through Wednesday, for instance, waves in New England’s coastal waters will build to three to six feet with strong rip currents along the South Coast in swell emanating from the north side of Tropical Storm Arthur as the storm prepares to turn south toward Bermuda. Sandwiched between Arthur and the Canadian fair weather cell, high-altitude, wispy cirrus clouds will mix with sun while our wind will gust up to 30 mph at times Tuesday from the northeast, keeping coastal communities cooler than the interior, owing to ocean water temperatures only around 50 degrees, and most New England communities will only feel like the 50s at the warmest time of Tuesday thanks to the breeze. Tuesday night temperatures will drop into the 30s north and 40s south under partly cloudy skies with a quieting wind as high pressure expands, delivering a lighter onshore wind Wednesday under ample sunshine. Thursday and Friday the wind begins to change direction as the center of high pressure drifts from Atlantic Canada to a position southeast of New England, with the clockwise flow of air around its center delivering a southerly wind for high temperatures in the 70s Thursday and a southwest wind with highs in the 80s Friday! Meanwhile, the second storm mentioned over the Ohio Valley will send a piece of upper atmospheric energy east into New England on Saturday, likely to increase our clouds and possibly touching off a few showers, though right now showers seem unlikely given the abundance of dry air, then Sunday returns to more sunshine with both weekend days featuring highs from 60 at the coast to 70 inland as an onshore wind returns. Memorial Day once again features a shifting wind to blow from the south, bumping temperatures into the 70s under sunshine, and a warm, southwest wind returns through the middle of next week in the last three days of our exclusive First Alert 10-day, with high temperatures expected to soar well into the 80s.
While the weather world turned attention to the development of Tropical Storm Arthur this weekend, developing before the official start of hurricane season and brushing along the Outer Banks of North Carolina on this Monday, here in New England the forecast hasn’t changed with regard to Arthur: no direct impact for most of us. “Most of us” excludes mariners, where swell moving north of Arthur’s path from North Carolina to Bermuda will arrive to our coastal waters Tuesday, building seas three to six feet. Otherwise, the big feature for New England is a large and strengthening dome of high pressure – fair weather – over Atlantic Canada, flexing its muscle and ensuring not only Arthur but also a separate storm over the Great Lakes will stay away from New England. Instead, New England sees a dry stretch of weather after Monday morning sprinkles associated with a passing disturbance aloft come to a close by mid-morning, though clouds will remain stubborn through most of Monday. With the abundance of clouds, black flies – now hatched and biting in most of New England – will be especially aggressive, so bug spray isn’t a bad idea. From Tuesday onward, we’ll swap bug spray for sunscreen – or perhaps combine the two in some spots – as sunshine makes a comeback, dry weather continues, and a continuing onshore wind will mean coolest daytime temperatures near the coast in the 50s while inland spots rise into the 60s each day. The stretch of dry weather will ensure pollen count remains high through the week, with pine pollen ready to burst in the days ahead and join birch, oak and lingering maple that have all been driving allergy sufferers to the tissues, and will lead New England gardeners and those trying to grow grass seen to set up sprinklers to keep the tender plants and sprouts from drying out. As the wind shifts direction later Thursday, temperatures rise a bit, and a continuing shift in wind to blow from the southwest by Friday likely means we’ll end the week around 80 degrees, even in Boston and along the coast, before an onshore wind takes hold again for Saturday and Sunday of Memorial Day weekend, with Memorial Day itself brining a southerly wind to bump temperatures into the 70s Monday, en route to 80 again by the middle of next week. Along the way, our First Alert Team will monitor showers expected to be over Pennsylvania this Friday, with a low chance of about 20% those showers may slide into New England on Saturday or Sunday of the holiday weekend, though right now chances are better those showers dry up on approach, leaving us with variable clouds but mostly dry conditions in our exclusive First Alert 10-day forecast.