Marine Weather and Tide Forecast for Plymouth, MA
 | Sunrise 5:17 AM Sunset 8:02 PM Moonrise 8:46 AM Moonset 12:00 AM |
Marine Forecasts
NOTE: Zones updated 4/16/2026. Some zones changed. Use Edit if needed.
ANZ231 Cape Cod Bay- 105 Am Edt Wed May 20 2026
Rest of tonight - SW winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave detail: sw 2 ft at 3 seconds and se 1 foot at 9 seconds.
Wed - SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave detail: sw 2 ft at 3 seconds and se 1 foot at 10 seconds.
Wed night - W winds around 10 kt, becoming N after midnight. Seas around 2 ft. Wave detail: nw 2 ft at 3 seconds and S 1 foot at 11 seconds. A chance of showers.
Thu - N winds around 10 kt, becoming ne in the afternoon. Seas around 2 ft. Wave detail: N 2 ft at 4 seconds and S 1 foot at 11 seconds.
Thu night - S winds around 5 kt, becoming nw after midnight. Seas 1 foot or less. Wave detail: N 1 foot at 5 seconds and se 1 foot at 10 seconds.
Fri and Fri night - SW winds 5 to 10 kt. Seas 1 foot or less. Wave detail: N 1 foot at 4 seconds and se 1 foot at 10 seconds.
Sat through Sun night - E winds 5 to 10 kt with gusts up to 20 kt. Seas around 2 ft. A chance of showers.
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.
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.
ANZ200 105 Am Edt Wed May 20 2026
Synopsis for massachusetts and rhode island coastal waters - A strong cold front will cross the waters late Wed and Wed evening. Strong high pres builds over the gt lakes Thu and moves into the waters Fri. The high moves offshore by Sat as a frontal boundary approaches from the s.
7 Day Forecast for Marine Location Near Plymouth, MA
NEW! Add second zone forecast
| Duxbury Click for Map Wed -- 02:30 AM EDT 12.31 feet High Tide Wed -- 05:17 AM EDT Sunrise Wed -- 08:46 AM EDT Moonrise Wed -- 09:17 AM EDT -0.99 feet Low Tide Wed -- 03:10 PM EDT 10.30 feet High Tide Wed -- 08:01 PM EDT Sunset Wed -- 09:32 PM EDT 0.54 feet Low Tide Tide / Current data from XTide NOT FOR NAVIGATION |
Duxbury, Duxbury Harbor, Cape Cod Bay, Massachusetts, Tide feet
| 12 am |
| 7.6 |
| 1 am |
| 10.3 |
| 2 am |
| 12.1 |
| 3 am |
| 12.1 |
| 4 am |
| 10.6 |
| 5 am |
| 8.3 |
| 6 am |
| 5.6 |
| 7 am |
| 2.9 |
| 8 am |
| 0.5 |
| 9 am |
| -0.9 |
| 10 am |
| -0.5 |
| 11 am |
| 1.5 |
| 12 pm |
| 4 |
| 1 pm |
| 6.7 |
| 2 pm |
| 9.1 |
| 3 pm |
| 10.3 |
| 4 pm |
| 9.8 |
| 5 pm |
| 8.3 |
| 6 pm |
| 6.3 |
| 7 pm |
| 4.2 |
| 8 pm |
| 2.3 |
| 9 pm |
| 0.8 |
| 10 pm |
| 0.7 |
| 11 pm |
| 2.4 |
| Cape Cod Canal Click for Map Flood direction 53 true Ebb direction 233 true Wed -- 12:29 AM EDT -0.00 knots Slack Wed -- 03:02 AM EDT -3.76 knots Max Ebb Wed -- 05:17 AM EDT Sunrise Wed -- 06:44 AM EDT 0.00 knots Slack Wed -- 08:46 AM EDT Moonrise Wed -- 09:29 AM EDT 3.75 knots Max Flood Wed -- 01:23 PM EDT -0.00 knots Slack Wed -- 03:45 PM EDT -3.52 knots Max Ebb Wed -- 07:13 PM EDT 0.00 knots Slack Wed -- 08:00 PM EDT Sunset Wed -- 09:35 PM EDT 3.26 knots Max Flood Tide / Current data from XTide NOT FOR NAVIGATION |
Cape Cod Canal, east end (depth 8 ft), Massachusetts Current, knots
| 12 am |
| 0.9 |
| 1 am |
| -1.1 |
| 2 am |
| -3 |
| 3 am |
| -3.8 |
| 4 am |
| -3.4 |
| 5 am |
| -2.6 |
| 6 am |
| -1.5 |
| 7 am |
| 0.6 |
| 8 am |
| 2.6 |
| 9 am |
| 3.7 |
| 10 am |
| 3.7 |
| 11 am |
| 3.3 |
| 12 pm |
| 2.6 |
| 1 pm |
| 0.9 |
| 2 pm |
| -1.5 |
| 3 pm |
| -3.2 |
| 4 pm |
| -3.5 |
| 5 pm |
| -3 |
| 6 pm |
| -2.2 |
| 7 pm |
| -0.5 |
| 8 pm |
| 1.7 |
| 9 pm |
| 3.1 |
| 10 pm |
| 3.2 |
| 11 pm |
| 2.7 |
FXUS61 KBOX 200550 AFDBOX
Area Forecast Discussion National Weather Service Boston/Norton MA 150 AM EDT Wed May 20 2026
WHAT HAS CHANGED
Signs of potentially salvaging at least one dry weekend day, but uncertainty remains high.
KEY MESSAGES
- Final day of record warmth today with highs in the 90s away from the immediate coast. Chance for strong to severe thunderstorms by the afternoon with a risk for damaging winds and some hail.
- Cooler temperatures through Memorial Day Weekend. Unsettled weather returns for the weekend with periods of rain possible, but confidence is low.
DISCUSSION
KEY MESSAGE 1...Final day of record warmth today with highs in the 90s away from the immediate coast. Chance for strong to severe thunderstorms by the afternoon with a risk for damaging winds and some hail.
One more day with near record temperatures on tap before a drastic return to your regularly scheduled May weather. The Heat Advisory remains in effect as we see an anomolously warm airmass remaining overhead, even as the upper level ridge begins to break down.
Expecting a mix of sun and diurnal clouds, with westerly downslope flow once again contributing to temp maxima in the CT and Merrimack valleys. Again, will have to go to the immediate south coast to escape the heat but a slight shift in wind direction may bring those hot temps closer to the shore than on Tuesday. Relief then arrives behind a cold front which is dragged through the region from west to east between late morning and this evening.
This warm and moist airmass (dewpoints climb into the mid 60s)
produces a decent amount of instability, albeit a bit less than Tuesday, around 1,000 J/kg while model soundings show very steep low level lapse rates (8.5 C/km). Convergence ahead of the cold front will act on this airmass to produce a broken line of relatively shallow thunderstorms, limited in depth and organization by poor ML lapse rates and marginal 0-6 km bulk shear respectively. Unlike Tuesday's more northward severe risk, the best instability and resultant t-storm chance looks to be south of the MA pike where some damage wind gusts would be the main risk.
KEY MESSAGE 2...Cooler temperatures through Memorial Day Weekend.
Unsettled weather returns for the weekend with periods of rain possible, but confidence is low.
High pressure slowly builds in on Thursday into Friday suppressing any rainfall to the south; some guidance wants to keep rain close enough to the southern periphery to brush the south coast with rain showers the first half of Thursday. Ensemble guidance is a bit more bullish on measurable rainfall Thursday morning than the current forecast, so that may end up needing to be bumped up in the future.
Looking to the holiday weekend, as discussed last night the AI guidance continues to be dry, with a stronger high suppressing unsettled weather just to the south over the mid Atlantic while the traditional models are wetter and colder. That being said, the GFS continues to also suppress the rain south until Monday while the ECMWF has at least slowed the arrival, to perhaps salvage Saturday.
That being said, ensemble guidance doesn't seem to have caught on to any drying ideas, still bullish on rain both days (both the GEFS and EPS). The main idea is, there remains a great deal of uncertainty with regard to the holiday weekend, but still leaning the forecast on a wetter and cooler (50s and low 60s) solution. Temperature-wise, after a seasonable Thu/Fri in the upper 60s/low 70s the weekend is looking like it may be colder than normal for late May.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06Z TAF Update:
Through 12Z...High confidence. Low to moderate confidence for ACK CIGS
VFR overnight for most of the terminals. Possible IFR at ACK with areas of fog (lower confidence). SW winds 8-15 kts. LLWS possible for east and southeast terminals overnight.
Wednesday...Moderate confidence (TSRA chances).
VFR. Scattered TSRA along and ahead of a cold front in the afternoon and evening. Given widely scattered nature and uncertainty in location of TSRA, have included PROB30 groups for terminals PVD south. WSW winds 8-12 kts with gusts 20-25 kts turning NW behind the cold front between 16-00Z. Brief strong gusts possible in any thunderstorms.
Wednesday night...Moderate confidence.
VFR. Some SHRA may linger/expand over southern terminals overnight into Thursday morning. Light NW winds becoming N.
Thursday...High confidence.
VFR. Light winds.
KBOS...High confidence in TAF.
KBDL...High confidence in TAF.
Outlook /Thursday through Sunday/...
Thursday through Friday: VFR.
Friday Night through Saturday Night: VFR. Chance SHRA.
Sunday: VFR. Breezy. Chance SHRA, slight chance TSRA.
MARINE
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Wednesday: High confidence.
Small craft advisories remain in effect through 06z Thurs. SW winds of 15-25 kt continues this afternoon and overnight Seas will also be building to around 4-6 ft, with some 7 footers possible tonight over the southern waters.
Mainly dry weather prevails through tonight with a few showers or thunderstorms possible for the northern waters., Some fog may persist and expand across the southern waters tonight on increasing southwest winds.
Outlook /Thursday Night through Sunday/...
Wednesday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Local rough seas. Slight chance of rain showers.
Wednesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers.
Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.
Thursday Night through Friday: Winds less than 25 kt.
Friday Night: Winds less than 25 kt. Chance of rain showers.
Saturday through Saturday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Chance of rain showers.
Sunday: Winds less than 25 kt. Local rough seas. Chance of rain showers.
CLIMATE
Record Highs for Wed May 20...
BOS 91/1996 BDL 99/1996 PVD 95/1996 ORH 91/1903
BOX WATCHES/WARNINGS/ADVISORIES
CT...Heat Advisory until 8 PM EDT this evening for CTZ002>004.
MA...Heat Advisory until 8 PM EDT this evening for MAZ003>007- 010>019-026.
RI...Heat Advisory until 8 PM EDT this evening for RIZ001>004.
MARINE...Small Craft Advisory until 2 AM EDT Thursday for ANZ254>256.
Area Forecast Discussion National Weather Service Boston/Norton MA 150 AM EDT Wed May 20 2026
WHAT HAS CHANGED
Signs of potentially salvaging at least one dry weekend day, but uncertainty remains high.
KEY MESSAGES
- Final day of record warmth today with highs in the 90s away from the immediate coast. Chance for strong to severe thunderstorms by the afternoon with a risk for damaging winds and some hail.
- Cooler temperatures through Memorial Day Weekend. Unsettled weather returns for the weekend with periods of rain possible, but confidence is low.
DISCUSSION
KEY MESSAGE 1...Final day of record warmth today with highs in the 90s away from the immediate coast. Chance for strong to severe thunderstorms by the afternoon with a risk for damaging winds and some hail.
One more day with near record temperatures on tap before a drastic return to your regularly scheduled May weather. The Heat Advisory remains in effect as we see an anomolously warm airmass remaining overhead, even as the upper level ridge begins to break down.
Expecting a mix of sun and diurnal clouds, with westerly downslope flow once again contributing to temp maxima in the CT and Merrimack valleys. Again, will have to go to the immediate south coast to escape the heat but a slight shift in wind direction may bring those hot temps closer to the shore than on Tuesday. Relief then arrives behind a cold front which is dragged through the region from west to east between late morning and this evening.
This warm and moist airmass (dewpoints climb into the mid 60s)
produces a decent amount of instability, albeit a bit less than Tuesday, around 1,000 J/kg while model soundings show very steep low level lapse rates (8.5 C/km). Convergence ahead of the cold front will act on this airmass to produce a broken line of relatively shallow thunderstorms, limited in depth and organization by poor ML lapse rates and marginal 0-6 km bulk shear respectively. Unlike Tuesday's more northward severe risk, the best instability and resultant t-storm chance looks to be south of the MA pike where some damage wind gusts would be the main risk.
KEY MESSAGE 2...Cooler temperatures through Memorial Day Weekend.
Unsettled weather returns for the weekend with periods of rain possible, but confidence is low.
High pressure slowly builds in on Thursday into Friday suppressing any rainfall to the south; some guidance wants to keep rain close enough to the southern periphery to brush the south coast with rain showers the first half of Thursday. Ensemble guidance is a bit more bullish on measurable rainfall Thursday morning than the current forecast, so that may end up needing to be bumped up in the future.
Looking to the holiday weekend, as discussed last night the AI guidance continues to be dry, with a stronger high suppressing unsettled weather just to the south over the mid Atlantic while the traditional models are wetter and colder. That being said, the GFS continues to also suppress the rain south until Monday while the ECMWF has at least slowed the arrival, to perhaps salvage Saturday.
That being said, ensemble guidance doesn't seem to have caught on to any drying ideas, still bullish on rain both days (both the GEFS and EPS). The main idea is, there remains a great deal of uncertainty with regard to the holiday weekend, but still leaning the forecast on a wetter and cooler (50s and low 60s) solution. Temperature-wise, after a seasonable Thu/Fri in the upper 60s/low 70s the weekend is looking like it may be colder than normal for late May.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06Z TAF Update:
Through 12Z...High confidence. Low to moderate confidence for ACK CIGS
VFR overnight for most of the terminals. Possible IFR at ACK with areas of fog (lower confidence). SW winds 8-15 kts. LLWS possible for east and southeast terminals overnight.
Wednesday...Moderate confidence (TSRA chances).
VFR. Scattered TSRA along and ahead of a cold front in the afternoon and evening. Given widely scattered nature and uncertainty in location of TSRA, have included PROB30 groups for terminals PVD south. WSW winds 8-12 kts with gusts 20-25 kts turning NW behind the cold front between 16-00Z. Brief strong gusts possible in any thunderstorms.
Wednesday night...Moderate confidence.
VFR. Some SHRA may linger/expand over southern terminals overnight into Thursday morning. Light NW winds becoming N.
Thursday...High confidence.
VFR. Light winds.
KBOS...High confidence in TAF.
KBDL...High confidence in TAF.
Outlook /Thursday through Sunday/...
Thursday through Friday: VFR.
Friday Night through Saturday Night: VFR. Chance SHRA.
Sunday: VFR. Breezy. Chance SHRA, slight chance TSRA.
MARINE
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Wednesday: High confidence.
Small craft advisories remain in effect through 06z Thurs. SW winds of 15-25 kt continues this afternoon and overnight Seas will also be building to around 4-6 ft, with some 7 footers possible tonight over the southern waters.
Mainly dry weather prevails through tonight with a few showers or thunderstorms possible for the northern waters., Some fog may persist and expand across the southern waters tonight on increasing southwest winds.
Outlook /Thursday Night through Sunday/...
Wednesday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Local rough seas. Slight chance of rain showers.
Wednesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers.
Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.
Thursday Night through Friday: Winds less than 25 kt.
Friday Night: Winds less than 25 kt. Chance of rain showers.
Saturday through Saturday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Chance of rain showers.
Sunday: Winds less than 25 kt. Local rough seas. Chance of rain showers.
CLIMATE
Record Highs for Wed May 20...
BOS 91/1996 BDL 99/1996 PVD 95/1996 ORH 91/1903
BOX WATCHES/WARNINGS/ADVISORIES
CT...Heat Advisory until 8 PM EDT this evening for CTZ002>004.
MA...Heat Advisory until 8 PM EDT this evening for MAZ003>007- 010>019-026.
RI...Heat Advisory until 8 PM EDT this evening for RIZ001>004.
MARINE...Small Craft Advisory until 2 AM EDT Thursday for ANZ254>256.
Wind History for Borden Flats Light at Fall River, MA
toggle option: (graph/table)
| Airport | Dist | Age | Wind kt | Vis | Sky | Weather | Air | DewPt | RH | inHg |
| KGHG Marshfield Municipal George Harlow Field US | 10 sm | 24 min | WSW 06G11 | 10 sm | Partly Cloudy | 68°F | 63°F | 83% | 29.88 | |
| KPYM Plymouth Municipal Airport US | 12 sm | 47 min | SSW 03 | 10 sm | Clear | 63°F | 59°F | 88% | 29.91 | |
| KPVC Provincetown Municipal Airport US | 18 sm | 43 min | SSW 10 | 8 sm | Clear | 57°F | 29.91 | |||
| KFMH Cape Cod Coast Guard Air Station US | 24 sm | 43 min | WSW 10 | 10 sm | Clear | 61°F | 57°F | 88% | 29.95 |
Link to 1 hour of 5 minute data for KPYM
Terminal Aerodrome Forecast (TAF) for KPYM
Wind History Graph: PYM
(wind in knots)
GEOS Local Image of Northeast
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