textproduct: Boston / Norton

WHAT HAS CHANGED

Heavy snow has ended and light snow showers will continue through the day on Monday.

KEY MESSAGES

- Periods of light to moderate snow continue behind low pressure as it pulls offshore Monday.

- Abnormally cold and mostly dry with yet another storm possible off the coast next weekend.

DISCUSSION

Key Message 1...Periods of light to moderate snow continue behind low pressure as it pulls offshore Monday.

The surface low is well into the north Atlantic by noon today and the expected dry slot has moved overhead shutting off efficient snow making. So, while lingering wrap around moisture will continue to produce light snow across the region today, lack of moisture and the strong forcing that we saw on Sunday will mean much less in the way of additional snowfall today. Overall, expecting 1-2 inches in inland SNE with 2-5 inches more likely as you get closer to the extreme eastern and northeastern MA coastline. This is where NE wind trajectory off the water together with convergence ahead of a front late in the day will lead to a pickup in snow coverage by the afternoon/evening.

Key Message 2...Abnormally cold and mostly dry with yet another storm possible off the coast next weekend.

Quiet weather then follows our active start to the week as dry, abnormally cold NW flow lingers overhead most of the week. snowstorm. Temperatures remain well below normal each day. Normal highs/lows for late January are in the mid 30s and low 20s respectively; we are forecasting highs in the teens and 20s with lows in the single digits thanks to an anomalously cold airmass overhead. A few shortwaves rounding the broader trough could bring some flurries off and on but on the whole things look dry. We continue to monitor a potential storm off the coast toward next weekend. Can we make it 3 sunday coastal storms in a row? We'll see!

AVIATION /12Z MONDAY THROUGH FRIDAY/

Forecaster Confidence Levels...

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

12z Update

Monday: High Confidence in trends. Moderate Confidence in timing.

Light snow continues this morning and through the evening. Prolonged northeasterly flow brings ocean enhanced snow to the northeastern coastal plain, including Boston, through evening.

Monday Night: High Confidence.

MVFR, becoming VFR. Sky cover becoming clear. NW wind 10 knots with gusts 20 knots.

Tuesday: High Confidence.

VFR. Mid-level clouds increase through the day with winds decreasing and shifting WSW.

KBOS Terminal...High Confidence in TAF.

KBDL Terminal...High Confidence in TAF.

Outlook /Tuesday Night through Friday/...

Tuesday Night through Wednesday: VFR. Breezy.

Wednesday Night: VFR.

Thursday through Friday: VFR. Breezy.

MARINE

Forecaster Confidence Levels...

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

Through Tuesday: High confidence.

Gale-foce wind from the northeast gusting 30-40 knots this morning over the eastern waters as the low exits. Seas 10-12 ft. Wind shifts northwest Monday afternoon with gusts less than 20 knots. With the shift in wind, snow showers are possible Monday afternoon, followed by drying conditions Monday night. Monday night into Tuesday winds gust 25-40 kts with seas 7-10 ft.

Outlook /Tuesday Night through Friday/...

Tuesday Night: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Areas of rough seas. Slight chance of snow.

Wednesday: Winds less than 25 kt. Local rough seas.

Wednesday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of snow.

Thursday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of seas approaching 5 ft. Chance of freezing spray, slight chance of snow.

Thursday Night: Strong winds with gusts up to 30 kt. Seas up to 5 ft. Chance of freezing spray, slight chance of snow.

Friday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Chance of freezing spray.

BOX WATCHES/WARNINGS/ADVISORIES

CT...Winter Storm Warning until 8 PM EST this evening for CTZ002>004. MA...Winter Storm Warning until 8 PM EST this evening for MAZ002>022-026. RI...Winter Storm Warning until 8 PM EST this evening for RIZ001>007. MARINE...Small Craft Advisory until 7 AM EST Tuesday for ANZ230-231-250- 251-254. Small Craft Advisory until 1 AM EST Tuesday for ANZ232>235-237- 255-256.