TSR Extended Range Forecast for Northwest Pacific Typhoon Activity in 2018
TSR predicts the 2018 Northwest Pacific typhoon season will see activity slightly above the 1965-2017 norm. However, forecast uncertainties remain large.
The TSR (Tropical Storm Risk) extended range forecast for Northwest Pacific typhoon activity in 2018 anticipates a season with activity around 5% above norm. The forecast spans the period from 1st January to 31st December 2018 (95% of typhoons occur historically after 1st May) and employs data through to the end of April 2018. The forecast includes deterministic and probabilistic projections for overall basin activity, and deterministic projections for the ACE index and numbers of intense typhoons, typhoons and tropical storms. TSR’s main predictor for overall activity is the forecast anomaly in August-September Niño 3.75 (region 5˚S-5˚N, 140˚W-180˚W) sea surface temperature (SST) which we anticipate being 0.11±0.5°C warmer than normal (1965-2017 climatology). A warm Niño 3.75 SST would have an enhancing effect on typhoon activity. However, sizeable uncertainties remain in the ENSO forecast for August-September 2018. Updated forecasts for Northwest Pacific seasonal typhoon activity will be issued in early July and early August.
Source: The above comes from the TSR report issued on May 11th, 2018 Here is a link to the complete report:
http://www.tropicalstormrisk.com/docs/TSRNWPForecastMay2018.pdf