Generally speaking the leftover E’ly flow in the South Pacific looks weaker and less persistent and thus residual E’ly swell will likely fade in the mix faster than Wed’s notes suggested.
After a very slow moving synoptic pattern in the Xmas-New Years week we are finally seeing some movement as the tropical low which hived off the monsoon trough now journeys into the Southern Tasman, leading to easing swells across the region, where it will merge with a surface trough currently working it’s way north along the NSW Coast.
A tropical low which hived off the monsoon trough and which has been providing days of chunky E swell to sub-tropical regions is now, finally, on the move. Compared to model runs the system has been much more slow moving than f/cast- which is maintaining plenty of strong E swell across our sub-tropical region.
No change to the weekend f/cast. E/NE swell across our region continues as the main body of the fetch remains aimed at sub-tropical targets. The high in the Tasman is maintaining a moderate onshore SE flow which is favouring the protected Points.
A dual-centred high straddles New Zealand with an elongated monsoonal low pressure trough located in the Coral Sea and extending into the near South Pacific. This is creating a long and broad E’ly fetch which is slowly extending southwards. As we near the end of the week, a more discrete surface low hives off the end of the monsoonal low pressure trough and retrogrades back into the Tasman Sea as it intensifies, generating large E’ly swells over the last days of 2022 and first days of 2023.
We’re now on the cusp of a dynamic, tropical induced blocking pattern with low pressure hiving off an active monsoon trough in the Coral Sea and meandering in Coral Sea before drifting down into the Northern Tasman. The high pressure belt holds good support for this low pressure area with reinforcing cells stacking onto a slow moving system located at South Island latitudes. This will see an extended E’ly swell event, with days of pumping E swell ahead.
The broad pattern will be setting up by Boxing Day with a dominant, slow moving high in the Tasman and low pressure expected to form along the monsoon trough line in the Coral Sea and in the South Pacific near the North Island. That will see at least dual swell producing fetches aimed at the Eastern Seaboard, favouring our subtropical region for most size.
Models are now firming on a trough of low pressure forming near the North Island early next week and retrograding in a SW direction back towards the Eastern seaboard
The combination of a Tasman low and strong high moving through the Bight has supplied a stack of S swell to the f/cast region since late last week, with an intensification and N’ward movement of the low upping the size and local winds through today on the MNC, and across the rest of the region through tomorrow. Pressure gradients will now slowly ease as the low starts to dissipate and the strong high weakens as it moves South of Tasmania through tomorrow.
There's no evidence to suggests any deviation away from the current regional trend for the east swell.