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Nantasket Beach surf break

Nantasket Beach surfForecast / Massachusetts / USA

information circle48hr Weather and Surf, issued 1 am Monday 20 Apr 2026 EDT
Forecast update in hr  min  s Forecast update imminent
Nantasket Beach surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Nantasket Beach sea temperature is
7.7° C
(Which is 1.7°C warmer than normal for this time of year)

How big are the waves at Nantasket Beach today?

The current surf forecast for Nantasket Beach at 6AM is: 0.5m 7s primary swell from a East direction and 0.2m 5s secondary swell from a North-northeast direction (forecast issued at 01:00am April 20). An open ocean swell of 0.3m 3s is not directed at the surf break. The wind direction is predicted to be offshore.

Time (EDT) & DateWave HeightWave Period
Morning (20 Apr)1.5ft (0.4m)7s
Afternoon (20 Apr)1.5ft (0.4m)7s
Evening (20 Apr)1.5ft (0.4m)7s

Table - waves today at Nantasket Beach. (Swell directed towards the surf break)


Updates in  hr  min  s Forecast update imminent
Monday
20
Tuesday
21
Wednesday
22
11PM2AM5AM8AM11AM2PM5PM8PM11PM2AM5AM8AM11AM2PM5PM8PM11PM2AM5AM8AM11AM2PM5PM8PM
Rating
(10 max)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Swell
Height Map
Wave Height (m) & direction (?)
0.6
E
0.6
E
0.5
E
0.4
E
0.4
E
0.4
E
0.4
E
0.4
E
0.4
E
0.4
E
0.4
E
0.7
NE
0.6
NNE
0.6
ENE
0.5
NE
0.5
ENE
0.3
E
0.3
E
0.3
E
0.3
E
0.3
E
0.3
E
0.7
SSE
0.4
SE
Period(s) (?)777777778885455577777755
Wave
Graph
(?)Metric surfscale
Energy kJ (?)37352315151515161818202212171113999988196
Wind
(km/h)
20
WNW
20
W
15
W
15
W
15
W
15
W
10
W
25
N
20
NNE
15
NNE
15
N
15
N
10
NE
10
E
20
SE
25
SSE
20
SSW
20
SSW
20
SSW
20
S
25
SSW
15
SSW
10
SW
5
SW
Wind State (?)
onshore
cross-onshore
cross-shore
cross-offshore
offshore
glassy
offoffoffoffoffoffoffcrosscrosscrosscrosscrosscross-
on
oncross-
on
crosscross-
off
cross-
off
cross-
off
crosscross-
off
cross-
off
cross-
off
glass
High Tide
/ height (m)
1:35AM
3.42
2:16PM
2.97
2:27AM
3.35
3:11PM
2.85
3:22AM
3.21
4:10PM
2.73
Low Tide
/ height (m)
8:01AM
-0.41
8:13PM
0.01
8:55AM
-0.30
9:07PM
0.13
9:53AM
-0.15
Monday
20
Tuesday
21
Wednesday
22
Sunrise---5:54-------5:54-------5:52----
Sunset------7:30-------7:30-------7:31-
clear
clear
clear
clear
cloud
cloud
cloud
part cloud
cloud
part cloud
clear
clear
clear
clear
clear
clear
cloud
cloud
cloud
light rain
light rain
cloud
cloud
cloud
Rain (mm)
-------------------11---
Temp. °C5434791064423465544224677
Feels °C (?)-1-2-2-1135-1-2-2-4-2-11-2-2-3-3-4-4-2245
  • Map Icons:
  • Break
  • Live Wave Height (m)
  • Live Wind Speed (km/h)
  • Surf Rating (10 Max)
  • Ocean Swells (m)
  • Wind Speed (km/h)
Map placeholder

FREE! Surf-Forecast.com widget for your website

The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Nantasket Beach surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.


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