Skip Navigation Links 
NOAA logo-Select to go to the NOAA homepage National Weather Service Forecast Office   Select to go to the NWS homepage
Pacific ENSO Applications Climate Center
banner piece
  banner piece
Local forecast by
"City, St" or Zip Code
Pacific ENSO Update

3rd Quarter, 2012 Vol. 18 No. 3



The TSR (Tropical Storm Risk) consortium1 places the odds of lower, middle and upper terciles for western North Pacific tropical cyclone activity during 2012 at 16-39-45, respectively. This is a forecast biased toward above-normal activity, although the TSR forecasted numbers look to be just slightly above normal in the table below:

NW Pacific ACE Index and System Numbers in 2012


ACE Index

Intense Typhoons

Tropical Typhoons


TSR Forecast (±FE)

324 (±90)

9.2 (±2.4)

16.7 (±3.4)

26.8 (±4.2)

47yr Climate Norm (±SD) 1965-2011

295 (±106)

8.4 (±3.0)

16.3 (±3.8)

26.2 (±4.6)

Forecast Skill at this Lead





In a telling sign of the times, the climate research center at the City University of Hong Kong has declined to issue a forecast of western North Pacific TC activity until the reasons for the recent decadal trend to very low activity can be determined. As of May 2012, experimental forecasts for the annual total of western North Pacific TC activity issued by Paul Stanko (Senior forecaster, Guam WFO) indicated that the most likely category of 2012 TC activity would be “near normal” (among seven groupings ranging from “record high” to “record low”).

Given the available guidance 1, the PEAC anticipates that the tropical cyclone activity for the remainder of 2012 will be slightly above normal in the western North Pacific basin and near normal within Micronesia. The level of threat to individual islands is included in their local variability summaries. Given the recent lack of cyclone activity, a normal distribution of tropical cyclones may seem like quite a busy year for some locations in Micronesia. If El Niño develops quickly and were to become moderate or strong (although a strong El Niño is not anticipated at this time), then the tropical cyclone distribution for Micronesia in the latter half of 2012 could be above normal, with several serious threats to many islands. With a similar frame of mind as the Hong Kong forecasters, it is not clear to us how the recent trend to low activity will temper the typical effects of El Niño to raise the level of tropical cyclone activity within Micronesia. Outlooks for the level of activity in the next Southern Hemisphere cyclone season will appear in next quarter’s ENSO Newsletter.

1 The PEAC tropical cyclone forecasts for 2011 are based on forecasts of the status of ENSO and input from three seasonal outlooks for tropical cyclone activity in the western North Pacific basin: (1) The Guam Weather Forecast Office (WFO), (2) The City University of Hong Kong Laboratory for Atmospheric Research, under the direction of Dr. J. C-L. Chan, and (3) The Benfield Hazard Research Centre, University College London, TSR research group, UK, led by Dr Adam Lea and Professor Mark Saunders.

Pacific ENSO Applications Climate (PEAC) Center
c/o NOAA NWS - Weather Forecast Office Honolulu
2525 Correa Road, suite 250
Honolulu, HI 96822
(808) 956-2324

Web Master's email:
Page Last Modified: December 12 2012 23:18:30 GMT


Privacy Policy
About Us
Career Opportunities