DAYS 1-5 (JULY 4-8)
Happy Independence Day! I’ve been eyeing a frontal boundary set to pass through the region today, weakening / washing out as it does so, but it holds just enough impact to produce a few showers this morning, mainly north of I-90, and, with the help of a South Coast sea breeze boundary, potentially initiate a few more this afternoon, mainly south of I-90. A little disturbance coming along tonight can bring a very late evening or overnight shower or thunderstorm to some areas, but that activity will be fairly low coverage. Other than those few showers and maybe a spot storm around today, and some fog patches which may form this evening near the South Coast, I don’t see much in the way of weather-related interruption for daytime 4th of July activities and evening fireworks displays. As always, keep an eye on the sky, and the radar if you can, and stay safe. As we move through the extended holiday weekend, and you can include Monday in this if you are lucky enough to have done so, we’ll see some unsettled weather around for a while Friday and Saturday, and more settled weather Sunday and Monday. The frontal boundary that comes by today, even though it’s not showing much contrast from one side to another, sits around Friday just to the south when a few showers can form over it with the help of an approaching disturbance from the west. As a trough moves into the Great Lakes this weekend, a stronger push of moisture will occur into the Northeast Saturday, upping the potential for a couple rounds of showers and thunderstorms at any point during that day. While I wouldn’t cancel plans, keep in mind that this is the day that has the highest chance of outdoor plans being interrupted by weather. The passage of a warm front early in the day will open the door to oppressive humidity, but this should drop off again during Sunday as a cold front settles through. Clouds may hang on for a while on Sunday before sun reappears, and it will be quite warm even behind the front, including Monday, which will feature fair weather.
TODAY (INDEPENDENCE DAY): Mostly cloudy morning with passing showers possible. Partly sunny afternoon with an additional shower or thunderstorm possible, mainly south of I-90. Highs 75-82 Cape Cod / South Coast, 82-89 elsewhere. Dew point rises into 60s. Wind SW 5-15 MPH.
TONIGHT: Mostly cloudy. A passing shower is possible, especially late evening and overnight. Patchy fog South Coast. Lows 63-70, warmest urban areas. Dew point 60+. Wind SW up to 10 MPH.
FRIDAY: Variably cloudy. A passing shower or thunderstorm possible. Highs 76-83, coolest coast. Wind S to SE up to 10 MPH.
FRIDAY NIGHT: Mostly cloudy. Increasing chance of showers and possibly a thunderstorm overnight. Patchy fog. Lows 63-70. Dew point 60+. Wind SE to S up to 10 MPH.
SATURDAY: More clouds than sun. Showers and thunderstorms possible at any time, but greatest chance early morning and mid afternoon. Highs 78-85, coolest South Coast. Dew point rises to 70+. Wind S to SW 5-15 MPH.
SATURDAY NIGHT: Variably cloudy. A passing shower or thunderstorm possible. Patchy fog. Lows 63-70. Dew point lowers to lower 60s. Wind SW up to 10 MPH shifting to W.
SUNDAY: Clouds dominate the morning, sun dominates the afternoon. Highs 83-90 except a little cooler in some coastal areas. Dew point 60+. Wind W up to 10 MPH but some coastal sea breezes possible.
SUNDAY NIGHT: Mostly clear. Fog patches in lower elevations. Lows 61-68. Dew point near 60. Wind W under 10 MPH.
MONDAY: Mostly sunny to partly cloudy. Highs 84-91 except a little cooler in coastal areas. Dew point near 60. Wind variable up to 10 MPH with coastal sea breezes developing.
DAYS 6-10 (JULY 9-13)
The large scale weather pattern features high pressure off the US East Coast, a low pressure trough Great Lakes and Midwest, which creates a humid southwesterly air flow here, with warm weather and several opportunities for showers and thunderstorms. It sounds worse than it is, as I don’t expect persistent major heat. There will also be more rain-free time than raining time. Day-to-day details have to be worked out closer to each time frame.
DAYS 11-15 (JULY 14-18)
No major changes from the previous outlook. Indications of a generally westerly flow aloft with a mean trough position in the Great Lakes and Midwest and weaker high pressure off the East Coast. This is a typical summertime pattern for here, warm, a hot day or two, on the humid side, a few shower/thunderstorm chances from time to time but fair weather more often than unsettled weather.