DAYS 1-5 (SEPTEMBER 17-21)
The cold front that crawled across our region late Wednesday and Thursday is washing out near the South Coast today, never really having delivered much dry air, and now we have an established onshore air flow for today and tonight as low pressure organizes off the US Mid Atlantic Coast and heads north then northeastward. A combination of moisture from this low and the old frontal boundary keeps the chance of showers near the South Coast, especially Cape Cod and the Islands, for a while today, but the bulk of the moisture from this low will be passing southeast of New England through early Saturday. The low itself is acquiring tropical characteristics and will likely become a tropical depression and eventually a tropical storm as it makes its trek over the water off the coast. This has some indirect impact on our weekend, sending higher swells and rough surf back to the coast, increasing rip current risk for late-season beach visits. Use caution if planning to be in the water, especially Sunday. As for our weekend weather, drier air will start to move in as that low moves away during Saturday, but a weakening cold front will also be moving across the region from the northeast Saturday evening. It looks like most of the shower activity with this front will stay to the north of our area. High pressure then builds in during Sunday through early next week, the center of it probably staying just north to east of the region, with fair weather being the result.
TODAY: Mostly cloudy. Scattered showers Cape Cod and Islands region mainly this morning. Patchy drizzle possible eastern coastal locations. Highs 67-74. Wind E 5-15 MPH.
TONIGHT: Mostly cloudy. Foggy areas. Lows 60-67. Wind NE under 10 MPH.
SATURDAY: Mostly cloudy start with areas of fog, then increasing sun especially away from the coast. Highs 68-75. Wind N 5-15 MPH.
SATURDAY NIGHT: Variably cloudy. A passing shower possible mid to late evening. Lows 55-62. Wind NW up to 10 MPH.
SUNDAY: Mostly sunny. Highs 70-77. Wind NW 5-15 MPH.
SUNDAY NIGHT: Clear. Areas of ground fog in lower elevations. Lows 53-60. Wind calm.
MONDAY: Sunny. Highs 72-79, coolest coast. Wind variable to E 10 MPH.
MONDAY NIGHT: Clear. Areas of ground fog in lower elevations. Lows 53-60. Wind calm.
TUESDAY: Sunny. Highs 73-80, coolest coast. Wind SE up to 10 MPH.
DAYS 6-10 (SEPTEMBER 22-26)
High pressure shifts offshore by the beginning of this period with a warm start to the period. The next weather questions to answer will be the timing of a trough / cold front from the west, which I think comes through sometime September 23 with an opportunity for showers, before drier and cooler air comes in behind that for September 24 before it warms up September 25. Will watch for the approach of the next weather system with wet weather chances for the very end of the period, though it may be slow enough to allow our region to get through the September 25-26 weekend rain-free.
DAYS 11-15 (SEPTEMBER 27 – OCTOBER 1)
Wet weather may start this period before a shot of dry and cooler air, a quick warm-up, more unsettled weather, then another shot of cool air to end September and start October. While timing is lower confidence the confidence is higher for an overall west-to-east pattern being the cause of the changeable weather.