Trearddur Bay (Holy Island) Surf Forecast and Surf Report

Right then, let’s have a look at the 16-day picture for Trearddur Bay (Holy Island). Honestly, it’s a bit of a tough watch. The data shows a whole lot of small, weak swell and tricky wind for the first couple of weeks. There’s a real gap of poor conditions before we get a couple of more interesting days right at the end of the window. Let’s break it down.

The water temp is sitting at 62°F, which is a touch warmer than normal for this time of year, so your wetsuit might be a bit more comfortable than usual.

Monday, the 10th of August, kicks off with a tiny 1.0ft SW swell at 6 seconds. Combined energy is only 5, so it’s barely a ripple. The wind is a cross-off from the N at 9 mph, which keeps the surface clean, but there’s just no power to work with. Tuesday and Wednesday are even smaller, with onshore and cross-onshore breezes making it messy. The period on Wednesday morning is a long 12 seconds, but the swell height is only 0.3ft, so it’s just a tease.

We get a bit of a pulse on the 14th and 15th. Friday the 14th morning sees a 2ft NW swell, energy of 27, but it’s a cross-shore wind at 12 mph, so it’s choppy. Saturday the 15th morning is a bit better: a 3ft NW swell, energy of 30, with a cross-off breeze from the NW at 16 mph. That’s clean, but the swell is still short period at 4 seconds, so it’s a bit weak and lacking shape. Not a standout.

The next week stays pretty flat and poor. There’s a day on the 19th of August with a very long period, 16 seconds, from the SW, but it’s only 0.3ft. The wind is glassy in the morning, which is lovely, but there’s nothing to ride.

The real interest comes on the 21st and 22nd of August. Friday the 21st afternoon brings a 6ft SSW swell, energy of 266, so it’s got some moderate power. The problem is the wind is a strong cross-on from the SSW at 25 mph, which is going to tear it to pieces. That’s more of a kite day than a paddle day for most.

The standout of the whole outlook is Saturday, the 22nd of August. This is the one to have your eye on. The morning shows a 8ft WNW swell, with a combined energy of 461 – that’s *strong*. The period is 6 seconds, so it’s a wind swell, not a groundswell, but it’s got plenty of push. The wind is a cross-shore from the NW at 16 mph, which will be a bit bumpy. The afternoon gets even better: an 8ft WNW swell, energy of 620, and the wind drops to a light 6 mph cross-shore from the NW. That’s a whole lot of wave energy and clean conditions. At 8ft, this is firmly in the "experts only" zone – it’s going to be big and powerful. If you’re experienced and you’re looking for a proper session, this is your window. The swell direction is from the WNW, which is a bit off the optimum SW, but with that much energy, it’ll still wrap in.

After that, it fades quickly. The 23rd and 24th are back to tiny, long-period leftovers that won’t break properly. The 25th of August shows a little 3ft SSW swell, energy of 51, with clean cross-off winds, but it’s a small, short-period wave.

So, bottom line: the first two weeks are a write-off. The only real chance for a decent wave is Saturday the 22nd of August. That afternoon session is your best bet, but it’s for the experienced crew.

Rusty.

Read more