Cape Cod Bay Marine Forecast
|Today...Nw Winds 20 To 25 Kt With Gusts Up To 35 Kt, Diminishing To 15 To 20 Kt With Gusts Up To 25 Kt This Afternoon. Seas 4 To 7 Ft.|
|Tonight...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt, Becoming Ne 5 To 10 Kt After Midnight. Seas 2 To 4 Ft.|
|Thu...S Winds 5 To 10 Kt. Gusts Up To 20 Kt In The Afternoon. Seas Around 2 Ft.|
|Thu Night...Sw Winds 5 To 10 Kt. Gusts Up To 20 Kt In The Evening. Seas Around 2 Ft.|
|Fri...W Winds 5 To 10 Kt, Becoming Sw 10 To 15 Kt In The Afternoon. Gusts Up To 25 Kt. Seas 2 To 4 Ft.|
|Fri Night...Nw Winds 15 To 20 Kt, Becoming N 20 To 25 Kt After Midnight. Gusts Up To 35 Kt. Seas 3 To 5 Ft.|
|Sat...N Winds 20 To 25 Kt With Gusts Up To 35 Kt. Seas 5 To 8 Ft.|
|Sat Night And Sun...Ne Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 4 To 6 Ft.|
|Sun Night...Ne Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 3 To 5 Ft. A Chance Of Rain. Seas Are Reported As Significant Wave Height, Which Is The Average Of The Highest Third Of The Waves. Individual Wave Heights May Be More Than Twice The Significant Wave Height.|
Area Forecast Discussion|
National Weather Service Boston/Norton MA
1007am EST Wednesday Nov 13 2019
High pressure building in from the west will become centered over New England tonight. It will bring record cold temperatures today, along with gusty winds this morning. As the high moves off the coast, temperatures begin to moderate on Thursday, but will still be below normal for the middle of November. Even milder weather is forecast for Friday, but then another strong cold front will deliver unseasonably cold temperatures Friday night through Saturday night. An ocean storm may impact the region Sunday night into Monday with rain and wind along the coast and pockets of interior ice.
Near Term - Until 6pm This Evening
Current forecast on track so no major changes. Winds gradually diminish today, with record cold temperatures under sunny skies.
Previous discussion... Strong, large high pressure builds eastward into New England today providing completely sunny skies. Despite the sunshine, we are expecting record cold temperatures. Highs will be hard pressed to break 32 in most areas and will likely remain in the 20s in northwestern MA. If so, this would break long-standing records for the lowest maximum temperature for this date in history. Boston's record low max temperature of 36 degrees has stood for 145 years...since 1874. Please see climate section below.
Northwest winds will be gusty this morning...up to 25-35 mph at times, but the pressure gradient will slacken this afternoon and winds will be correspondingly diminishing.
Short Term - 6pm This Evening Through 6pm Thursday
Tonight... High pressure overhead will mean light wind and cold temperatures. Skies will be clear before midnight, allowing for good radiational cooling. But models show an increase in mid and high level moisture overnight. Any mid cloudiness would probably be enough to prevent temperatures from dropping into the single digits. Am forecasting lows from 10 to 15 most areas, except lower to mid 20s outer Cape Cod and Nantucket.
Thursday... High pressure moves offshore, allowing a return flow of moist southerly air. A low level jet of 25-30 kt develops by afternoon across southern New England, increasing low level warm advection. Highs are forecast to reach the mid and upper 30s in the interior and 40s in RI and southeast MA.
Am believing the 3km NAM model which is the most emphatic at developing a rapid influx of low cloudiness from south to north during the late morning hours. It is very dry aloft, which means that as we saturate the low levels, drizzle or very light rain showers should develop in the afternoon, especially across RI and southeast MA. The air may be initially cool enough in the Merrimack Valley and in Worcester County for light snow to be mixed with any rain and drizzle. For now, have only introduced chance Probability of Precipitation of 30-35 percent for Thursday afternoon. Will have to see how this trends.
Long Term - Thursday Night Through Tuesday
Highlights... * Mainly dry with seasonable temps Fri * Turning much colder again Fri night into Sat night * An ocean storm may impact SNE Sunday night/Monday with rain and coastal wind along with pockets of ice possible in the interior
Thursday night... High pressure moves to the east with warm advection pattern developing. Low level moisture moves in by evening across SE New Eng and deepens a bit overnight as modest low level jet develops. Models are hinting at a weak inverted trough setting up across SE New Eng which may bring a few showers during the night, mainly across RI and SE MA. Low temps will drop into the 20s in the interior, but mid/upper 30s along the coast as southerly flow develops.
Friday into Saturday... Robust northern stream shortwave dives SE across northern New Eng which will deliver another strong cold front which drops S across SNE Fri night. Ahead of the front, expect dry conditions Fri with seasonable temps, then turning much colder Fri night into Sat behind the front as strong high pressure builds to the north on Sat. Temps well below normal although not quite as cold as current arctic airmass. Gusty N winds will result in wind chills in the single numbers and teens late Fri night and Sat morning. Expect a mainly dry frontal passage Fri night with mostly sunny skies Sat.
Sunday into Tuesday... It appears dry weather will hang on through Sunday as high pressure keeps moisture to the south. However, ocean storm will be approaching from the south and may impact the region Sunday night into Mon. Still lots of uncertainty with the track of the storm and how close it gets to New Eng with large spread among deterministic guidance as well as ECMWF (European Centre for Medium-Range Weather Forecasts) ensembles for track and Quantitative Precipitation Forecast. Also, uncertainty on a potential second storm approaching from the south on Tue. Will continue chance Probability of Precipitation as ECMWF ensembles show decent Quantitative Precipitation Forecast probs. Temps aloft are warming so rain will be favored, but high pressure to the north may provide enough low level cold air for some interior ice Sunday night/early Mon. It may also become windy along the coast depending on how close storm tracks to New Eng.
Short Term /through Thursday/...High confidence.
Gale Warnings were allowed to expire. Small Craft Advisories now posted for all coastal waters. As high pressure builds in from the west, the pressure gradient will weaken. Rough seas from 5 to 10 ft this morning over the outer waters will be subsiding this afternoon.
Tonight...seas of 5 feet linger on the outer waters this evening, but will then be subsiding to 2 to 4 ft. N winds 10-20 kt become light NE.
Thursday...Winds become S and increase to 15 to 20 kt in the afternoon. Chance of showers in the afternoon.
Outlook /Thursday Night through Sunday/... Thursday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers.
Friday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers.
Friday Night: Low risk for gale force winds with gusts up to 40 kt. Areas of rough seas.
Saturday: Moderate risk for gale force winds with gusts up to 40 kt. Rough seas up to 12 ft.
Saturday Night: Low risk for gale force winds with gusts up to 35 kt. Rough seas up to 10 ft.
Sunday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Rough seas up to 10 ft. Slight chance of rain showers.
Record Low Min Temps for Wednesday Nov 13
Boston 14/1883 Hartford 18/2001 Providence 19/2019 - previously 20/2001 Worcester 13/2019 - previously 15/1986
Record Low Max Temps for Wednesday Nov 13
Boston 36/1874 Hartford 33/1911 Providence 37/1911 Worcester 32/1962,2013
Record Low Min Temps for Thursday Nov 14
Boston 16/1905 Hartford 15/1986 Providence 16/1905 Worcester 10/1986
NOAA Boston MA Office: Watches - Warnings - Advisories
CT...None. MA...None. RI...None.
Small Craft Advisory until 1pm EST this afternoon for ANZ232>237. Small Craft Advisory until 6pm EST this evening for ANZ230- 231-251. Small Craft Advisory until midnight EST tonight for ANZ250-254- 255. Small Craft Advisory until 4pm EST this afternoon for ANZ256.