A deep mid-latitude low with high pressure support in the Bight and multiple cold fronts has now moved E of Tasmania with W to SW gales pushing out of Bass Strait and a deeper SSW fetch pushing up from the Southern Ocean into the Tasman Sea. It’s a wintry looking system and it has a nice sting in the tail as a small troughy intensification slingshots up into the Tasman Sea through tomorrow, giving another longer period pulse S swell to add onto the main body of the swell.

The troughy pattern will see multiple wind changes through to the end of the week with some flukey swells on offer before the inland low enters the Tasman this weekend and supplies a slightly larger S swell.

The fetch out of Cook Strait, extending up past Taranaki Peninsula and into the Tasman sea looked good on ASCAT (satellite windspeed) passes through Wed/Thurs, with areas of storm force winds embedded in a long fetch of severe gales to low end gales. With the buoys and observations already confirming the swell it’s only local winds we’ll be concerned with this weekend.

A low pressure system developing north of New Zealand’s North Island drifts south to be over the North Island Wed, and while that blocks most of the fetch from generating swell for the East Coast, it does shoot out a fetch through Cook Strait Wed/Thurs which looks like a tidy source of ESE swell for the region Fri/Sat.