Surf forecast for the weekend of Friday to Sunday 22-24 March 2024
By Spike, Friday morning
Summary
We're definitely into a transitional time between summer and winter as the ocean comes alive with storms and winds and swell all over the show, and on all sides of the SA coast - a giant storm in the far deep, a close feisty storm parking off SSW of Klapstad spewing a swell (that is yet to arrive) towards the SW Cape, and a big belt of east wind around the Indian Ocean High smashing a big washy east swell towards the East Coast.
Looking at the top weather Chart 1, we can see a mega storm in the deep south with a central pressure down to almost 940 mini-bars. That's a beast of a storm with some intense winds around it, and it is very far away (about 2,400 naughty miles away, which translates to two days travel time - ie late Sunday).
However, if you look in front of the storm, cutting right across the path of the swell, you will see a GINAORMOUSE SE facing fetch of wind, which might mangle the resulting 20 second long range swell that is due to arrive on Sunday night. With a lot of swell headed our way this weekend, the lower height of the huge period will be subsumed by the readings of bigger, shorter period swell. It's also downgraded a bit. Either way, we're in for lank swell, and lasting for up to a week too.
If you look at Chart 2 and the close up view of the storm off Slaapstad, you can see that it peaks this evening at 996mb and packs peak winds of 72kts. This swell has not arrived yet as of writing (and a quick check at the coast of Kommetjie, which is almost totally flat), but expect a raunchy blast of swell filling in tomorrow Saturday.
The first signs of the swell will be barely showing at dawn, so don't wake up too early on account of dawnie options. It gets bigger gradually all day, but very windswellish - a shotgun spray of high frequency lumpy 4-7ft storm swell that goes 8ft+ into the evening, spreading east overnight, with Sunday swell everywhere.
And then the third source of swell for the SA coast comes from that huge High pressure to the SE of the country. More precisely the source is more from the large band of wind over the top of the High and down the East Coast as the cooling descending air of the High rushes towards the vacuum created by the ascending air around the low pressure system, frothing up a big mangled easterly windswell this weekend almost all the way down the East Coat.
You can see all three sources of swell in the swell Chart 3 depicted as the orange, red and white blobs. The white blob in the deep south corresponds with the strongest core of the wind you can see in Chart 1 (25ft+ swell), while the orange and red colours in the blobs represents smaller swells.
More detailed details in the details below this broader detail below.
Day by Day
fri 22 mar 2pm - wind
Stiff onshores blow down the East Coast, which is messy and mangled. Quite solid 4-6ft+ east windswell that side, with a calm patch around JBay into the S Cape. The SW storm lurks SW of your picture. Weskus flat. Kapstad flat, but you can see the wodge of stormsea approaching SW Cape.
fri 22 mar 2pm - swell
sat 23 mar 7am - wind
The storm moves closer to Slaapstad, but no real sign of swell yet, barring perhaps some disorganised bumps filling in gradually. The High rules the East Coast, with lots of east swell and NE onshores. A weak low over the S and E Cape brings fresh NW and / or general offshore winds.
sat 23 mar 7am - swell
sat 23 mar 5pm - wind
By late arvi, KZN and a big part of E Cape caned by NE onshores while the rest of the Cape has variable light to moderate S to SW breezes and a biggish lumpy storm sea is filling in along the SW Cape and Weskus, but its a close range, messy looking swell due to storm proximity.
sat 23 mar 5pm - swell
sun 24 mar 7am - wind
The NE is searing down the East Coast with a vengeance, and its nasty and blown out, but again, a tale of two halves with the western side mild W breezes as storm influences the weather, with solid mixed direction 4-8ft chunks of ocean. Open breaks exposed and messy and chunky.
sun 24 mar 8am - swell
sun 24 mar 5pm - wind
Horrid NE to yeast windswell to the East is wild and messy and miff, while the W storm starts to bring moderate to fresh NW to the SW Cape and lank swell all over the show. A SW buster is mustering in the S Cape in the arvi. The stiff NW winds from the storm only really bite Klapstad by late arvi.