
Surf Forecasts:
Grandma's surf forecast from 1 Aug 2026:
- Best quality surf: Saturday 1 Aug, 11AM (local time) - 1.5ft (0.5m), 14s period, SW swell with offshore winds.
- Most powerful swell: Friday 7 Aug, 5PM (local time) - 1.5ft (0.4m), 20s period, SW swell with 99 kJ wave energy.
- Next surfable swell (1★+): Saturday 1 Aug, 11AM (local time) - 1.5ft (0.5m), 14s period with SW swell.
Best Forecast Surf Conditions for Grandma's this week:
The surf forecast for Grandma's over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Saturday (Aug 01) at 11AM. The primary swell is predicted to be 0.5m and 14s period. The wind is predicted to be offshore as the swell arrives.
The most powerful waves expected at Grandma's in the next 16 days are 0.4m 20s and forecast to arrive on Friday (Aug 07) at 5PM. Winds are predicted to be offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 2.3m 7s period and expected on Saturday (Aug 01) at 11AM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 11AM (Sat 1st Aug) | 1.5ft (0.5m) 14s |
| Best Surf | 11AM (Sat 1st Aug) | 1.5ft (0.5m) 14s |
| Most Powerful | 5PM (Fri 7th Aug) | 1.5ft (0.4m) 20s |
Table - best surf conditions forecast for Grandma's over the next 16 days.
The Lowdown
Righto, grab a coffee and settle in, because the next two weeks at Grandma's are a real tale of two halves. The first week is pretty flat and ordinary, but the second week has some serious potential if you're patient.
The water is sitting at 80°F which is 0.9°F warmer than average for this time of year, so it's right about where you'd expect it for a summer dip.
The first week of August is a bit of a write-off. We're looking at surf that's barely ankle to knee high, 1ft to 2ft from the SW, with combined swell energy in the weak to moderate range (49 to 180). The wind is mostly offshore or glassy, which would normally be a good sign, but there's just no swell to work with. It's surfable in the sense you can paddle around, but it's very ordinary. The standouts don't exist here. The afternoon of Saturday the 3rd and Sunday the 4th have some glassy moments, but the wave size is just too small to get excited about.
Then things start to change around the 10th of August. Monday the 10th brings a real shift. The morning kicks off with 2ft from the SSW at 16 seconds, with a combined energy of 367 (moderate), glassy wind and clean conditions. That's a proper groundswell starting to show. The afternoon stays clean with a cross-offshore breeze and 3ft. Tuesday the 11th is glassy again in the morning and the swell is building. The afternoon has a spike – 2ft but from the S with a 20-second period, sending energy up to 606 (strong). This is where it gets interesting.
The real standout is Wednesday the 12th of August. The morning is glassy with 3ft of S swell at 18 seconds, and the combined energy is a cracking 848 (strong to very strong). The afternoon is even better with 4ft at 17 seconds and nearly 900 (888) units of energy, glassy conditions. This is the best of the entire forecast. The long period (over 15 seconds) means these waves will have real shape and power, but at a reef break like Grandma's, that's a dream. It's not a beginner wave – 4ft here with that period will be a solid, punchy wave. It's for the intermediate and above crew. The crowds are likely here, as it's often busy, but for conditions like that, you'll forgive the company.
Thursday the 13th is still good, with 3ft in the morning and a glassy afternoon, but the energy dips a bit. It's a great follow-up day.
So, the call is this: the first week is a patience test. The second week, specifically Wednesday the 12th of August, is the one to circle on the calendar. It's the standout. The swell direction is right on the optimum (SW), the wind is perfect, and the energy is pumping. Don't sleep on the 11th afternoon either.
Stay frothy.
Rusty
Short Range ForecastMostly dry. Warm (max 29°C on Sat afternoon, min 24°C on Sat night). Wind will be generally light. | Days 4-6 Weather SummaryLight rain (total 5mm), mostly falling on Wed afternoon. Warm (max 28°C on Wed afternoon, min 25°C on Tue morning). Wind will be generally light. | ||||||||||||||||||||
Saturday 1 | Sunday 2 | Monday 3 | Tuesday 4 | Wednesday 5 | Thursday 6 | Friday 7 | |||||||||||||||
AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map | |||||||||||||||||||||
Wave Height (m) Direction Period (s) | SW 14 | SW 14 | SW 14 | SW 14 | SW 13 | SSW 13 | SSW 13 | SSW 12 | SSW 12 | SSW 12 | SSW 11 | SW 15 | SW 15 | SW 15 | SW 14 | SW 14 | SW 14 | SSW 14 | SW 14 | SW 20 | SW 19 |
Wave Graph | |||||||||||||||||||||
93 | 91 | 97 | 50 | 40 | 58 | 53 | 49 | 48 | 45 | 43 | 57 | 39 | 60 | 53 | 51 | 53 | 81 | 49 | 99 | 95 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | off | off | off | off | off | off | cross-off | cross-off | off | glassy | off | glassy | glassy | cross-off | glassy | glassy | glassy | cross-off | cross-off | off | off |
High Tide | 5:59PM0.65m | 6:57AM0.45m | 6:30PM0.58m | 7:54AM0.50m | 7:05PM0.50m | 8:59AM0.56m | 7:47PM0.42m | 10:07AM0.62m | 8:49PM0.34m | 11:13AM0.69m | 10:23PM0.29m | 12:14PM0.76m | 11:54PM0.27m | ||||||||
Low Tide | 11:18AM0.11m | 00:34AM0.05m | 12:12PM0.16m | 1:06AM0.04m | 1:17PM0.22m | 1:42AM0.03m | 2:38PM0.26m | 2:24AM0.02m | 4:22PM0.27m | 3:14AM0.02m | 6:20PM0.24m | 4:12AM0.01m | 7:41PM0.19m | ||||||||
6:00 | — | — | 6:00 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | — | |
— | 7:04 | — | — | 7:02 | — | — | 7:02 | — | — | 7:01 | — | — | 7:01 | — | — | 7:00 | — | — | 7:00 | — | |
mm | — | — | — | — | — | — | — | — | — | — | 1 | — | — | 3 | 1 | — | — | — | — | — | — |
Temp °C | 28 | 29 | 26 | 28 | 28 | 25 | 27 | 27 | 26 | 27 | 27 | 26 | 27 | 28 | 27 | 28 | 27 | 27 | 28 | 30 | 26 |
Feels °C | 30 | 30 | 26 | 28 | 29 | 25 | 29 | 28 | 27 | 31 | 30 | 29 | 31 | 31 | 31 | 31 | 31 | 30 | 31 | 32 | 27 |
Swell 1 Height (m) Direction Period (s) | SW 14 | SW 14 | SW 14 | SW 14 | SW 13 | SSW 13 | SSW 13 | SSW 12 | SSW 12 | SSW 12 | SSW 11 | SSW 11 | SSW 11 | SSW 11 | SSW 10 | SW 14 | SW 14 | SSW 14 | SW 14 | SW 14 | ESE 6 |
93 | 91 | 97 | 50 | 40 | 58 | 53 | 49 | 48 | 45 | 43 | 40 | 39 | 39 | 22 | 51 | 53 | 81 | 49 | 46 | 16 | |
Swell 2 Height (m) Direction Period (s) | ESE 7 | SE 6 | NNE 7 | NNE 7 | NNE 7 | SW 12 | SW 13 | NNE 6 | N 6 | N 6 | SSW 16 | SW 15 | S 13 | SW 15 | SW 14 | SE 5 | SSW 10 | ESE 6 | ESE 6 | SW 20 | SW 13 |
19 | 13 | 9 | 9 | 9 | 40 | 26 | 11 | 6 | 2 | 26 | 57 | 29 | 60 | 53 | 4 | 18 | 3 | 3 | 99 | 45 | |
Swell 3 Height (m) Direction Period (s) | S 12 | S 11 | SE 6 | SSW 14 | S 11 | NNE 6 | NNE 6 | SSW 13 | SSE 5 | SSW 16 | S 14 | S 13 | SW 15 | S 12 | S 12 | S 11 | S 11 | S 11 | SSW 21 | S 11 | SW 19 |
42 | 22 | 5 | 39 | 9 | 8 | 8 | 16 | 2 | 27 | 14 | 31 | 36 | 26 | 25 | 23 | 10 | 21 | 44 | 20 | 95 | |
Wind waves Height (m) Direction Period (s) | E 7 | E 7 | ENE 2 | E 8 | E 8 | E 5 | — | — | E 11 | E 11 | NNE 3 | E 4 | E 4 | E 9 | E 4 | E 5 | WNW 3 | E 5 | E 6 | E 6 | E 6 |
524 | 328 | 1 | 320 | 368 | 56 | — | — | 483 | 332 | 2 | 24 | 26 | 78 | 35 | 79 | 1 | 65 | 116 | 138 | 173 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 4 | 12 | 12 | 12 | 12 | 12 | 15 | 12 | 12 | 12 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
Best forecast wave conditions in Maui | |||||||||||||||||||||
Best forecast wave conditions in United States | |||||||||||||||||||||
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Information about the Grandma's Surf forecast
The above surf forecast table for Grandma's provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Grandma's can be found by selecting the local surf guide option on the grey menu. Our Grandma's surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Grandma's) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).
Further information to help with frequently asked questions about our surf forecast for Grandma's may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.
Are you planning a vacation in Maui? If you are looking for accommodation near Grandma's, camping, hotels and condos and appartments in Maui, consider staying in Kihei which is 10 km (6 miles) away. Other places in and around Maui where you can find information about places to rent, and car hire include Wailuku which is 12 km (7 miles) away, Kahului, Lanai - Lanai and Kaunakakai - Molokai.











