
Rhode Island Sound Marine Forecast
This Afternoon...W Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 2 To 4 Ft. Wave Detail: W 4 Ft At 5 Seconds And S 1 Foot At 9 Seconds. Light Freezing Spray. |
Tonight...Nw Winds 10 To 15 Kt. Gusts Up To 20 Kt In The Evening. Seas 2 To 3 Ft. Wave Detail: W 3 Ft At 5 Seconds And S 1 Foot At 8 Seconds. |
Thu...N Winds 10 To 15 Kt. Gusts Up To 20 Kt In The Afternoon. Seas Around 2 Ft. Wave Detail: N 1 Foot At 4 Seconds And S 1 Foot At 8 Seconds. A Chance Of Snow In The Afternoon With Vsby 1 To 3 Nm. |
Thu Night...Nw Winds 10 To 15 Kt, Increasing To 15 To 20 Kt After Midnight. Gusts Up To 25 Kt. Seas 2 To 4 Ft. Wave Detail: N 3 Ft At 4 Seconds And S 2 Ft At 10 Seconds. A Chance Of Snow In The Evening. Light Freezing Spray After Midnight. Vsby 1 Nm Or Less In The Evening. |
Fri...Nw Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 3 To 4 Ft. Wave Detail: N 4 Ft At 5 Seconds And S 3 Ft At 9 Seconds. Light Freezing Spray In The Morning. |
Fri Night...Nw Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 2 To 4 Ft. Wave Detail: N 4 Ft At 5 Seconds And Se 2 Ft At 9 Seconds. A Chance Of Light Freezing Spray In The Evening. |
Sat Through Sun Night...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas 2 To 3 Ft. 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 949am EST Wednesday Feb 19 2025 Synopsis Partly sunny and still cold today...but with much less wind than the past two days. A distant ocean storm will brush the far southeast New England coast with some accumulating snow Thursday into Thursday night. Breezy and cold for Friday with the departure of a coastal low and the building high pressure system to the west. Drier conditions as well continues into this weekend with near normal temperatures. Early next week signs of some unsettled conditions and slightly above normal temperatures. Near Term - Through Tonight 10 am As expected winds are much less than the last few days, gusting 20-30 mph at this hour. Forecast remains on track. Key Messages... * Partly Sunny & still cold today but with less wind * Highs today mainly in the upper 20s/near 30 * Dry but cold tonight with lows mainly in the single digits & teens Details... Today... The pressure gradient relaxes today as a ridge of high pressure noses in from the west. There still will be a breeze from the northwest at speeds of 20-25 mph...but quite a bit less wind compared to the last two days. 925T are still quite cold in the -10C to -12C range...so highs will just be a few degrees higher than yesterday. Under partly sunny skies...highs should mainly be in the upper 20s to near 30...but with much less wind than the last two days it will feel more comfortable. Tonight... A ridge of high pressure continuing to nose in from the west will result in light/calm winds and a good night of radiational cooling tonight. Overnight low temps will mainly be in the single digits to the lower to middle teens in the urban centers. We may even see a few below zero readings in the typical coldest low-lying locations in western MA. Short Term - Thursday and Thursday Night Key Messages... * Snow grazes the far southeast New England coast Thu/Thu night * Most likely snow accums...1-3" for the Cape/MVY & 2-5" for ACK * Northwest extent of snow shield and accums may need to be refined Details... Thursday and Thursday night... The main forecast challenge Thu into Thu night revolves around the northwest extent of a snow shield from a distant ocean storm. This low pressure system will be passing well southeast of the Benchmark. Shortwave energy to the west coupled with subtle hints of an inverted trough will attempt to push the snow shield towards the far southeast New England coast. The question becomes just how far northwest does this snow shield reach? The guidance remains split with the NAM continuing to be the most robust and the UKMET/HRRR (High-Resolution Rapid Refresh) indicating very little snow even for the Cape and Islands. In a nutshell...do not think the main snow shield makes it much further northwest than the Cape Cod Canal outside of very immediate south coast and portions of Plymouth county. The main threat of accumulating snow appears to be across the Cape and Islands...especially Nantucket. The one thing that may be a bit of a bonus for them is the cold/moist northerly flow as a result of the distant ocean storm. This will result in the potential of ocean enhancement with a delta T close to 15C from the top of the mixed layer to the SST. We expect snow to develop during the daylight hours of Thu and continue at times through Thu night. Our best snowfall estimate at this time is for 1-3" across the Cape/Marthas Vineyard and 2-5" across Nantucket. We went ahead and issued a Winter Weather Advisory for Nantucket. If the storm system trends further northwest...later shifts may have to consider expanding the advisory onto the Cape/Marthas Vineyard and even a marginal warning scenario would arise for Nantucket. However...if the storm were to shift further southeast...snowfall accumulations would be limited to a coating to 2" across the Cape/Nantucket. Later shifts may certainly need to refine the forecast based on later model runs. Meanwhile...across the rest of the region expect generally dry weather to persist with just increasing clouds during the day Thu and persisting into Thu night. High temps should mainly be in the upper 20s to near 30. Lows Thu night will mainly be in the teens to the middle 20s. Long Term - Friday Through Tuesday Key Messages: * A lingering snow shower through Friday morning across far eastern Massachusetts, otherwise dry, cold, and breezy. * Fairly quiet weather this weekend and early next week. Will watch a weaker shortwave slides through late Saturday night into early Sunday, and then a potential clipper system for early next week. * Temperatures moderate this weekend into early next week. Friday: The low pressure system exits east of New England with high pressure, 1035+ mb, building over the central CONUS, resulting in a gusty period of weather due to the increased pressure gradient. At this time, gusts remain below advisory criteria, though it is breezy with gusts 20 to 30 MPH. Earlier in the morning, wind direction is from the north, this may lead to a few ocean enhanced snow showers across eastern coastal Massachusetts. As the wind direction becomes more northwest to west/northwest these snow showers should subside. Still a fairly cold day, considering average highs are between the mid-30s and 40F. With 925mb temperatures between -8C and -10C, this yields highs from the upper 20s to mid-30s. Dry conditions continue into the overnight as the column dries out with surface high moving east. Another chilly night ahead with lows in the single digits and teens, compared to the average low of the low and middle 20s. If the winds were to subside quicker, the forecast temperatures could be too "warm", resulting in better radiational cooling, thus would need to trend temperatures colder. Saturday and Sunday: High pressure breakdown over the course of the weekend, though should have fairly quiet weather during this period. A subtle mid-level trough and associated weak shortwave crosses the region sometime overnight Saturday into Sunday morning. Feel this results in added cloud cover with a low chance for an isolated snow shower. Temperatures trend slightly "warmer" with highs between the middle and upper 30s, and overnight lows from the mid teens to the mid-20s. Monday through Wednesday: Mid-level features a few subtle troughs and progressive shortwaves for the first-half of next week. While it isn't an overly active week, there could be a few nuisance features to keep us on our toes. Looking at ensemble guidance, there is some agreement that a clipper system may sweep across New England late on Monday night, perhaps early Tuesday, timing will be important if you were to want one PType. Daytime highs are trending slightly above normal Monday, Tuesday, and Wednesday with highs in the lower to middle 40s. Nightly lows are near normal in the mid-20s. Marine Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Today through Thursday...High Confidence. The pressure gradient will continue to gradually relax today...but still expect northwest small craft wind gusts into the afternoon for most of our waters. Winds and seas should lower later this afternoon and drop below small craft thresholds across all our waters by early evening. High pressure then noses in from the west keeping winds below small craft thresholds tonight into Thu. Thursday night...High Confidence. A distant ocean storm will intensify and allow the pressure gradient to increase. This will allow NW wind gusts of 20-30 knots to develop and small craft headlines will likely be needed for most of our waters. Outlook /Friday through Sunday/... Friday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Seas up to 5 ft. Chance of freezing spray. Friday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Chance of freezing spray. Saturday through Sunday: Winds less than 25 kt. Seas locally approaching 5 ft. NOAA Boston MA Office: Watches - Warnings - Advisories CT...None. MA...Winter Weather Advisory from 9am Thursday to 7am EST Friday for MAZ024. RI...None. Marine Small Craft Advisory until 1pm EST this afternoon for ANZ230- 232>237. Freezing Spray Advisory until 10am EST this morning for ANZ230>237-250-251-254>256. Small Craft Advisory until 4pm EST this afternoon for ANZ231- 250-251-254. Small Craft Advisory until 7pm EST this evening for ANZ255- 256. |