Scattered PM Storms Will Break 7 Day Heat Wave
Ugh! What a way to end a 7 day heat wave. Dewpoints are off the charts today with many areas in SNE in the mid-70's. Mix this in with another day of high heat with highs climbing to near 90-95...well, you know the story. Heat Advisory in effect until 7 PM with a Heat Index, otherwise called Humiture, feeling close to 100-104 this afternoon in the haze.
We are tracking two batches of scattered showers and storms today. One with a pre-frontal trough well ahead of the cold front, and then the cold itself. SW winds will be picking up today ahead of these boundaries to make for a good sailing day for our coastal waters. Most beaches will remain dry for most of the day. The pre-frontal trough, with scattered showers and storms in advance of the cold front, will push into Northern and western New England for the early afternoon hours. We may see some locally strong to severe weather. The SPC has us in a slight risk for these areas. At this point, it does not appear to be very unstable. Clouds, along with plenty of warm air aloft are helping to suppress storm development in this first phase. We will monitor. Any strong storm that does develop will come with heavy rain and the potential for damaging winds.
The second batch of scattered showers and storms is scheduled to push into SNE later today and tonight along with a cold front. This will be running into a more unstable and buoyant environment with a greater risk for scattered severe weather to develop. Again, it is not all coming together perfecting, with weak to moderate shear aloft, but these storms could come with some gusty winds, lightning and heavy rain between 5-9 PM, especially along and south of the Pike. Cape Cod and the islands will be dry all day, even into the evening...so no worries for you. In fact, many of us may not see much of anything with this frontal passage...because of the scattered nature, pulse type variety storms they will be. Still, we will monitor the storms for you and keep a close eye on your radars as the skies begin to darken if you have any outdoor plans.
Once the front is off the coast, Sunday will turn gorgeous with sunshine, lower humidity. The heat wave will finally be gone. Inland temps will still remain warm in the mi 80's with light NE winds providing cooling sea breezes at the coast keeping temps in the 70's and lwr 80's. What a relief.
We will hold onto the pleasant comfortable air right into Monday with light onshore winds and weak high pressure overhead.
The weak trough which is supplying the cooler drier air from Canada to break the heat, will start to dig in more along the east coast for the week ahead. SW winds aloft will keep a moist humid flow up the east coast which will mean periodic showers from Tuesday through Friday. Clouds, showers, with cooler onshore winds will help to keep temps in 70's and lwr 80's...more seasonal, a welcome return for sure...even the showers will be appreciated...but rainfall could start to add up, and may even wear out it's welcome by the weekend where the pattern should begin to break slightly.
This trough in the Northeast is going nowhere for the rest of the month of July, this will ensure cooler than normal temps and precip averaging slightly above normal up the east coast. We have likely seen the worst heat of the summer. It has been a hot stretch. Time to take the fuel off the fire.