Starting with the 2005 Tropical Cyclone season, the Central Pacific Hurricane Center will be producing experimental graphics products.

We welcome any and all feedback on these products. Please e-mail your comments to W-GUM.Webmaster@noaa.gov.

Background

• Collaborative effort between Central Pacific Hurricane Center (CPHC) and National Hurricane Center (NHC)
• Created when each tropical cyclone warning is issued by JTWC and is available on WFO Guam's website  http://www.prh.noaa.gov/guam/cyclone.php
• Supplement to the current deterministic products to communicate risk to users/partners
• Solicit feedback this typhoon season via the WFO Guam's webpage

Purpose

• Improved means of conveying forecast uncertainty using probability of wind speed exceeding particular thresholds
• Accounts for uncertainty in track, intensity and size of the tropical cyclone
• Focus on the size of the storm rather than only the center location and track forecast
• Provides users with information that enhances their ability to make preparedness decisions specific to their own situations

Forecast Components

• Incremental probabilities in 12 hour ranges (i.e., 0-12, 12-24, 24-36 etc) through 120 hours, or 5 days
• Indicates the chance that winds at the specified level will start during or before the particular period
• Specific sustained wind speed thresholds used:
• 34 kts (39 mph) - Tropical Storm strength
• 50 kts (58 mph)
• 64 kts (74 mph) - Typhoon strength