textproduct: Boston / Norton

WHAT HAS CHANGED

No significant changes to the forecast.

KEY MESSAGES

- Overcast conditions the rest of today give way to mostly sunny and breezy conditions on Sunday. Temperatures slightly cooler than normal through this weekend.

- Prolonged period of dry and quiet weather, with moderating temperatures next week, yielding mild afternoons and cool nights.

DISCUSSION

KEY MESSAGE 1...Overcast conditions the rest of today give way to mostly sunny and breezy conditions on Sunday. Temperatures slightly cooler than normal through this weekend.

Skies have trended toward mostly cloudy/overcast conditions with modest NW breezes, in response to a rather potent shortwave disturbance aloft seen on satellite imagery circulating near Montreal. While currently dry, there are a number of light but non- trace 1-hourly QPF amts being reported by METARs in northern New England; while dry weather generally prevails, a sprinkle or light shower are possible as this shortwave disturbance moves southward through Southern New England late this afternoon into early tonight. Any additional diurnal warming looks minimal today with the cloud cover and northerly breezes, in the upper 30s to the mid 40s! Early cloud cover and northwest breezes will keep temps from really dropping quickly, but decreasing clouds after midnight should bring lows down to the upper 20s to mid/upper 30s.

We do expect there to be more sunshine on Sunday compared to today, although low-level thermal profiles still are rather cool. This should support better mixing with northwest gusts in the 20 to 25 mph range, which will add a bit of a chill despite sunny conditions. Expect highs in the mid to upper 40s, but it will feel closer to the mid-30s if you're doing any hikes in the higher terrain.

KEY MESSAGE 2...Prolonged period of dry and quiet weather, with moderating temperatures next week, yielding mild afternoons and cool nights.

All guidance, including AI models, have large amplitude central US ridge this weekend slowly advecting to the East Coast next week. Hence, a prolong stretch of dry weather for SNE. Regarding temperatures, chilly to begin the week Monday, but height rises aloft will support warming temps and with surface high setting up across the OH Valley to the Mid Atlantic region, this will place SNE in a warming WNW flow. Given this setup, wouldn't be surprised if forecast highs overachieve into the mid 60s in the Wed-Fri timeframe! Thus, the temp theme next week will be cool highs in the upper 40s and lower 50s Monday, jumping into the 60s mid to late next week. These temps are about 10-15 degs warmer than normal for mid Nov.

Dew pts in the 30s along with light winds, will result in a large diurnal temp spread, with seasonably cool nights, as lows dip into the 30s for most locations. The mild daytime temps likely linger into Fri, before a dry cold front moves across the region Fri/Sat. Ensembles suggest not much of a post frontal airmass change, with highs only cooling back to seasonal levels, with highs in the 50s. Hence, mild days and cool nights will be the theme for much of next week.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

Forecaster Confidence Levels...

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

18z TAF Update:

Through 00z Sunday: High confidence.

BKN/OVC mainly VFR ceilings; although could briefly slip to MVFR at times late this. Isolated unrestricted- visby SHRA possible too, but majority of day ends up dry. NW winds around 10-14 kt with occasional gusts to 20 kt.

Tonight: High confidence.

Other than the Cape and Islands where ceilings could dip to MVFR through 03z, but VFR returns thereafter. NW winds around 8-12 kt.

Sunday...High confidence.

VFR. NW winds increase to around 10-13 kt with gusts in low 20s kt range by 14-16z.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Sunday Night through Thursday/...

Monday through Tuesday: VFR.

Tuesday Night through Wednesday: VFR. Breezy.

Wednesday Night through Thursday: VFR.

MARINE

Forecaster Confidence Levels...

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

Through Sunday Night: High confidence.

SCAs still continue through tonight with the potential for northwest wind gusts to pick up to around 25 kt again this afternoon into early tonight, before a steadier decrease overnight tonight. NW wind gusts could resume at near-SCA criteria (20 kt, brief periods 25 kt possible) on Sunday mid- morning through sundown. Seas should be 4 ft or less all waters, with good visibility.

Outlook /Sunday Night through Thursday/...

Monday: Winds less than 25 kt. Seas locally approaching 5 ft.

Monday Night through Thursday: Winds less than 25 kt.

BOX WATCHES/WARNINGS/ADVISORIES

CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 7 PM EST this evening for ANZ254. Small Craft Advisory until 7 AM EST Sunday for ANZ255-256.