Tokyo 2020 Early Forecast
A bleak, grey landscape, drained of saturation and accentuated by tetrapods. Dark, dull sands, concrete and a fishing port to boot. This is the site of surfings entrance into the Olympics, Tsurigasaki Surfing Beach, Chiba.
With the Paris 2024 Olympics using Teahupoo as their location for the surfing competition, there is no requirement for the surfing to be close to Tokyo (as seems to be the reasoning for using Tsurigasaki), there are much more picturesque locations to the north and south of Tokyo, with the south more likely to receive swell at this time of year.
Yet it's Tsurigasaki they've chosen, so Tsurigasaki it is.
The coastal alignment at Tsurigasaki is generally south to north, with exposure to incoming swells from the south-east to the north, as well as a degree of southerly wind protection due to the port and headland to the south.
At this time of year, any significant swell is likely to be sourced from typhoons and tropical activity to the south of Japan, with lower level background swells from easterly trade-swell energy. We're currently in the middle of the North Pacific typhoon season, but right now things are fairly subdued across the tropics.
What we usually see through typhoon season are tropical depressions forming north of Papua New Guinea, tracking to the west while deepening, then being steered north, up and into the Phillipines or Japan, bringing large, though generally short-lived swell events. The typhoons are then swept off to the north-east by upper level westerly winds.
This pattern can be seen in the 2021 typhoon season to date [see image below].
Looking out into the far end of the forecast, to the start date of the Olympic surfing event (25th of July), there's nothing substantial on the cards for the region.
Without typhoons the region has to rely on the background, easterly trade-swell energy, which there will be small levels of, though it rarely amounts to much size.
Long-range forecasts identify a couple of weak depressions in the trade-flow which could provide the catalyst for a typhoon, though it will require more monitoring which we'll do over the coming weeks.
In the meantime the competitors will be warming up in peaky, 2ft to occasionally 3ft, mid-period easterly swell. It's not hard to guess which country will dominate in those conditions.
Keep an eye on the 16-day Chiba regional forecast and WAMS below.