I’ll start with a disclaimer – I have zero beef with the forecast this week. It’s cool out, we’re back and forth with the clouds and sun, a few showers. Sounds fine. Worse things in the world than walking out the door with a jacket on in May, and of course we typically see a night or two going subfreezing in May. Plus, we know it could be a lot wilder this time of year! One of the most infamous storms in the New England history books is the May 9-10th snowstorm of 1977, exactly 40 years ago. It dumped almost 2 feet of snow on central Massachusetts and the higher elevations of Connecticut, and still stands as the latest measurable snow on record in the city of Boston. Truth be told, this week’s pattern isn’t *that* much different. But to get such an extreme event, you really need every single card to fall in place. Thankfully, that’s not going to happen.
There’s no doubting it though – it’s a cool stretch of weather. Reminds me a lot of Seattle for a good portion of the year. More clouds than sun, temperate air, and a few showers here and there. A caveat is that Seattle has had unusually horrid weather since October. Every single state across the Lower 48 has seen a warmer than average start to the year, except Washington. Cold, soaking, and miserable. For the sake of comparison, let’s toss out recent weather though and go with the usual climatology!
All in all, not a ton to sink your teeth into. We’ll get a few showers on Tuesday, Wednesday looks like the pick of the week, Thursday and Friday feature onshore winds. No record chill in play, no major rainfall. Each day slightly different but none with very impactful weather outside of a couple frost chances (especially Tuesday night). A pocket of cold air aloft means our weather will be very ‘diurnal’ – governed by the rising and setting of the sun. The time of day with maximum sunshine will be the morning hours, the cloudiest times will be midday and afternoon hours.
Since each day of the week is looking to be 5-10º below average, we’ll be running with a May well below average through early next week. And that’s pretty notable, because Boston hasn’t had a May with below average temperatures in almost a decade. Every single one since 2008 has featured above average temperatures, which also probably means this one will feel extra chilly.
Before the pattern can attempt to break down, there’s one more potential soaker looming. Saturday into Sunday, a coastal low is likely going to take shape off the Mid-Atlantic. There are still some questions as to whether this storm will be weak and graze us on its way out to sea, soak us, or be pushed out by northern stream energy yielding just some showers on Sunday. Kind of a snowstorm type of scenario involving phasing. It’s probably going to take a day or two more to see how these players will come together, but there’s a pretty decent signal that it’s going to get us. We’ll be updating the forecast this week as we get closer…and trust me I don’t want the ire of all the mothers out there looking for nice weather on their day!
Once into roughly the middle of next week, it looks like some ridging will be able to build in out ahead of a deep western trough. That will finally kick the cold out and help us warm a bit. I’m not sure I’m sold on it lasting for too long, but this time of year is notoriously fickle for a very long range outlook. We’ll keep our fingers crossed that we can get some well-timed warming by Memorial Day Weekend to pay us back for the chilly stretch!