Rhode Island Sound Marine Forecast
|Tonight...Ne Winds Around 15 Kt With Gusts Up To 20 Kt. Seas 4 To 5 Ft. Rain. Vsby 1 To 3 Nm.|
|Sat...Ne Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 4 To 6 Ft. Rain. Vsby 1 To 3 Nm.|
|Sat Night...N Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 4 To 6 Ft. A Chance Of Showers.|
|Sun...N Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 3 To 5 Ft.|
|Sun Night Through Mon Night...N Winds 15 To 20 Kt. Seas 2 To 4 Ft.|
|Tue Through Wed Night...E Winds 5 To 10 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
341pm EDT Fri September 29 2023
Low pressure south of New England will bring continued rain to southern New England into Saturday. High pressure builds into the region Sunday through much of the upcoming week, resulting in dry weather with a warming trend.
Near Term - Until 6am Saturday Morning
Axis of moderate to heavy rainfall continues to impact much of western MA/CT. Peak rainfall rates thus far are averaging 0.25- 0.50"/hr. Radar rainfall rates ha ve been overdone in western MA due to bright banding. We've had reports of 2-3 inches of rain in western half of Hartford county and an area flood warning was issued due to a few fast rising streams which have risen above flood stage, including North Branch Park River and the Bunnell Brook. Low level easterly flow is enhancing rates along the east slopes of the terrain in far western Hartford county near the Litchfield county line where localized 3-4 inch reports have been recieved.
The heaviest rainfall will remain focused in western MA/CT into this evening as not much change in the orientation and location of the low level jet and surface boundary. Additional rainfall of 1-2 inches is possible through tonight, especially from western Hartford county northward into the east slopes of the Berkshires. Rainfall rates will average up to 0.10-0.25"/hr but up to 0.50"/hr in the heaviest rain. Minor street flooding and minor small stream flooding is likely, especially in Hartford county and portions of western MA. Will also have to watch the Farmington river for possible flooding.
As the upper low moves approaches the mid Atlantic coast late tonight, the surface shifts south of the benchmark while the low level jet becomes more easterly and focused south of the Cape/Islands. This will shift the axis of heavier rainfall south of the Mass Pike and particularly across SE New England late tonight. Rain will remain light across NE MA further removed from the low level jet and deep moisture plume.
Short Term - 6am Saturday Morning Through Saturday Night
Saturday... The mid/upper low sets up south of New England with the comma head/trowal bringing periods of rain to SNE in the morning, especially across RI and SE MA where the rain may be heavy at times near the axis of the low level jet. Still some uncertainty on the strength and location of the low level jet which will determine the extent of heavy rainfall and whether it remains to the south or gets into SE New Eng. Rain will be ending in the interior and northern MA late morning and especially afternoon as pronounced mid level drying moves in from the N. However, the rain will continue for much of the day closer to the south coast. Gusty NE winds expected over Cape/Islands. Highs mostly 60-65, perhaps some upper 60s CT valley in northern MA if some sun can develop in the afternoon.
Saturday night... Mid level low slowly moves offshore as it drifts SE with gradual improving conditions. Clearing will develop in western New England and gradually push to the SE. However, showers could linger in SE New Eng for the first half of the night, especially Cape/Islands. Lows mid/upper 40s interior to low to mid 50s SE New Eng.
Long Term - Sunday Through Friday
* Prolonged stretch of dry weather with a warming trend.
Confidence continues to increase on having several days of dry weather next week along with a warming trend. Ensembles are in very good agreement that upper trough moves offshore Sunday and allows ridging to build across eastern third of country much of next week.
From there, although there are timing differences, ensembles agree in digging trough into northern Plains or Tennessee Valley by the end of the week. This will bring increasing chances for showers Friday as cold front approaches from Great Lakes, but if trough ends up slowing down, dry weather could last through Friday.
Forecaster Confidence Levels:
Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent.
Persistent NE winds through Sat night. Low level jet will bring increasing winds late tonight into Sat night as low pressure sets up south of the 40N/70W benchmark. Gusts 25-30 kt over the southern waters, but gusts to 20 kt over NE MA waters. SCA (Small Craft Advisory) will continue.
Outlook /Sunday through Wednesday/... Sunday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of rough seas. Slight chance of rain showers.
Sunday Night through Monday: Winds less than 25 kt. Seas up to 5 ft.
Monday Night through Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Tuesday Night through Wednesday: Winds less than 25 kt. Seas locally approaching 5 ft.
NOAA Boston MA Office: Watches - Warnings - Advisories
CT...None. MA...None. RI...None.
Small Craft Advisory from 2am Saturday to 8am EDT Sunday for ANZ232>234-250. Small Craft Advisory until 8am EDT Sunday for ANZ235-237- 254>256.