Looking back on a great run of surf
Talking to surfers along the East Coast, the feeling is unanimous that it's been one the best starts to winter in years, and if we were to include May then the last six weeks has been the best run of surf in a very long while.
It hasn't been overly sizable, though a large swell in early May rearranged the banks across most of the NSW coast, and with sand flowing northward since February, filling up many of the northern pointbreaks, it's been a stellar run.
Morning offshores, weak afternoon sea breezes - if any at all - and hardly a day under 2ft.
On the other hand, Western Australia has been smashed by persistent mid-latitude storms with widespread erosion and limited clean surf days around the Margaret River region. Perth and Mandurah have pumped in between cold fronts while the southern states have seen smaller swells though generally favourable conditions.
Looking at the Mean Sea Level Pressure and Wind anomalies for the months of May and June, the reason for our great run of surf becomes obvious.
During May, northern NSW and south-east QLD saw persistent long-range swell energy from the east. This pattern is clear on the charts below.
A strong high pressure anomaly (8hPa above average) is evident immediately east of New Zealand and the resultant winds were stronger than the long-term average by 7m/s. That being 25km/h or 13kts. The beauty of having this setup at arms length from the Australian continent is that we also saw favourable offshore breezes.
On the other side of the country though we can see the interaction of a low in the Southern Ocean and high across the Indian Ocean bringing onshore winds to WA's South West while generating westerly swells for South Australia and Victoria.
Into June, the high pressure anomaly east of New Zealand persisted and while it appears weaker than May, that's just the shift in colour scale and we saw an even stronger positive anomaly. The difference was a significant 13hPa above the long-term average (clearly visible on the higher-resolution Bureau of Meteorology charts), while what's interesting to point out is the low just west of New Zealand's North Island.
This setup allowed for more distant easterly trade-swell to filter in through most of June, while also generating swells from the east to south-east, originating from the eastern Tasman Sea, directly off New Zealand's western coasts.
A slight low pressure anomaly is observed south-west of Western Australia but there's no major trend in the wind anomalies as this is the time when we see weather and wind patterns shift more onshore.
The coming month looks to remain active for the East Coast with a week and a half of southerly swell possibly followed by easterly energy. While over in WA there'll be less consistent days of larger, onshore surf.
In between there's nothing too significant shaping up for the southern states (away from a possible sizey west swell in South Australia mid-month), though conditions will remain favourable. These finer details will be discussed in the Forecaster Notes over the coming weeks.