textproduct: Boston / Norton

WHAT HAS CHANGED

No significant changes to the forecast. Extended Small Craft Advisory through Tuesday night.

KEY MESSAGES

- Cloudy and unsettled start to this workweek as multiple weak disturbances pass by.

- Cloudy through midweek with more seasonable temperatures.

- Unsettled weather may return late this week.

DISCUSSION

KEY MESSAGE 1...Cloudy and unsettled start to this workweek as multiple weak disturbances pass by.

We remain under WNW flow with another upper level trough clearing the region later tonight, and with it cooler temperatures prevail aloft. Add in a passing mid level shortwave as well, and there is a risk for isolated to scattered light showers today, especially from late morning in to this afternoon. The risk for showers diminishes towards sunset. The greatest risk will be towards the higher terrain of western MA.

Breezy west to northwest winds into Tuesday as colder air moves into southern New England.

Drier weather should prevail tonight and Tuesday. Temperatures expected to be closer to normal as well.

KEY MESSAGE 2...Cloudy through midweek with more seasonable temperatures.

Another trough passes over the region Tuesday night into Wednesday morning, along with an associated surface low to our northeast, continuing the WNW to NW flow expected for the start of the week. 850 mb temperatures return to just below 0C for most of the region as well before improving slightly once more Thursday ahead an approaching strong closed low. 925 mb temperatures generally remain around 4-6C during this midweek period. These conditions will continue supporting more seasonable temperatures with highs in the 50s and lows in the 30s and 40s.

KEY MESSAGE 3...Unsettled weather may return late this week.

Towards the second half of next week, guidance has continued to indicate possible development of another low pressure originating from just to the south of the region along/just off the mid- Atlantic coast. This looks to be driven by a multitude of factors, starting with a trough developing off the Rockies by sometime Tuesday night/evening that will track eastward. As it does, ridging amplifies over the western CONUS and sets up over the Rockies by sometime Wednesday. The trough from the Rockies then may end up phasing with trough energy from the Canadian Prairies, which then tracks southeast, deepening into the Ohio Valley. This solution has started to become the main consensus even among the deterministic global guidance. Surface low pressure develops over the mid- Atlantic, then tracks northeast. Past this point midweek though and closer to the surface, details become more uncertain.

A lot of spread remains this far out regarding its track and what the potential impacts to southern New England could look like. 00Z GFS and GEFS guidance continues to favor a warmer, wetter solution as the low would track moreso directly over the region, with the colder air aloft not coming in until sometime Saturday morning. This would keep precip over much of the region as mostly rain, with a changeover to gloppy, wet snow possible towards the eastern slopes of the Berkshires and over the higher elevations of the Worcester Hills. At this time, this is not expected to be greatly impactful if this scenario is what pans out. Other guidance (ECMWF, Canadian suites) indicates a decent bit of colder air aloft, notably 850 mb temperatures below 0C, approaching the region a bit earlier, but the center of the low tracks closer to the 40N/70W benchmark, which would keep the region drier. Given the multiple facets associated with this potential system, more should become clearer as the details developing earlier this week come into focus.

Once this potential system pulls away, we're left with cyclonic flow aloft, leading to cloudy skies and cooler temperatures (especially as 850 mb temperatures look to fall to around -4C). Breezy NW winds look to take hold as well as more northerly to NW flow sets up over the region.

AVIATION /06Z MONDAY THROUGH FRIDAY/

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Through Tuesday...High confidence.

VFR for most. Local MVFR possible across the higher terrain of central and western MA. Mainly dry, but perhaps a few showers towards western MA. Dry weather prevails tonight and Tuesday.

Breezy once more starting in the late morning hours for most, gusting to 20-25 kt, especially for the higher elevations. Winds W becoming more NW through this afternoon. Gusts briefly diminish tonight, before increasing once more Tuesday morning.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Tuesday Night through Friday/...

Tuesday Night: VFR. Breezy.

Veterans Day through Wednesday Night: VFR.

Thursday: VFR. Breezy.

Thursday Night: Mainly VFR, with local MVFR possible. Windy with local gusts up to 30 kt. RA likely.

Friday: Mainly VFR, with local MVFR possible. Windy with gusts up to 35 kt. RA likely.

MARINE

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Through Tuesday...High confidence.

Lingering rough seas, mainly across the southern outer coastal waters. The rough seas across those waters are likely to persist through at least Tuesday, and perhaps longer. Small Craft Advisories continue for these areas.

Outlook /Tuesday Night through Friday/...

Tuesday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Local rough seas.

Veterans Day: Winds less than 25 kt. Seas up to 5 ft.

Wednesday Night: Winds less than 25 kt.

Thursday: Winds less than 25 kt. Slight chance of rain.

Thursday Night: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Areas of rough seas. Rain likely.

Friday: Strong winds with gusts up to 35 kt. Rough seas up to 11 ft. Rain likely.

BOX WATCHES/WARNINGS/ADVISORIES

CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 7 AM EST Wednesday for ANZ254>256.