A frontal zone slid across the Northeast Tuesday afternoon and evening (accompanied by some heavy rain and strong to severe thunderstorms over a good portion of the Mid-Atlantic and into parts of Southern New England) and slipped offshore overnight. Here on the Cape we saw a period of downpours and some thunder and lightning Tuesday evening…with most of the Cape seeing on the order of 1/10 to 1/3 of an inch of rain, with higher amounts over 1/2 inch recorded on parts of the Outer Cape. Precipitation tapered off during the mid to late evening hours as the complex of showers and storms pushed eastward and out to sea.Unfortunately, the surface boundary responsible for the wet weather didn’t make it too far to the south before it slowed its forward progress and it is now positioned a short distance south of Southern New England. Consequently, its shield of clouds and precipitation is lurking very close to the region and will result in a less than stellar day today (in fact, this general set-up will linger right into the weekend).
While we may see some breaks in the overcast this morning – maybe an hour or two of sunshine if we’re lucky – clouds to our south are expected to return northward today and that, combined with a northeast wind off the water, will hold temperatures under 60F for most of the day…with even some lower and middle 50s anticipated on the Outer Cape.
As for our wet weather chances: regional radar imagery shows showers over the Mid-Atlantic advancing north and eastward this morning and this activity will try to make a run at our area later today and into this evening. Most of our available model guidance shows at least some of this rainfall making it onto the extreme south coast of New England for a time this afternoon and tonight. However, the coverage and intensity of this activity is a bit of question mark as the brunt of the moisture is tracking eastward as opposed to northward and some dry air is trying to build southward into the area.
So whether we end up with nuisance sprinkles and pockets of light showers or a steadier light rain is the big forecast challenge for today and tonight. It does appear as though we will be right on the northern edge of the precipitation shield so the best chance of missing out on the wet weather would be on the far Outer Cape near Truro and Provincetown. It’s a good idea to monitor the radar through the afternoon.