210 likes | 476 Views
National Weather Service Central Pacific Hurricane Center/ Weather Forecast Office Honolulu, Hawaii Hurricane Preparedness - 2009. Jim Weyman Director/Meteorologist in Charge. Central Pacific Tropical Cyclone Season. Season: June 1 to November 30 Tropical Cyclones can occur in any month
E N D
National Weather Service Central Pacific Hurricane Center/ Weather Forecast Office Honolulu, Hawaii Hurricane Preparedness - 2009 Jim Weyman Director/Meteorologist in Charge
Central Pacific Tropical Cyclone Season • Season: June 1 to November 30 • Tropical Cyclones can occur in any month • Central Pacific Average per Year • 4-5 Tropical Cyclones • 1971 to 2008: 163 Tropical Cyclones • 36% Hurricanes, 28% Tropical Storms, 36% Tropical Depressions
Terminology • Tropical Cyclone: Generic term. Includes Tropical Depressions, Tropical Storms, and Hurricanes. • Tropical Depression: Winds of 38 mph or less. Assigned a number (e.g., TD-01C) • Tropical Storm: Winds of 39 to 73 mph. Assigned a name. • Hurricane: Winds of 74 mph or higher. Five Categories. Category 5 >155mph
Saffir/Simpson Scale Category Winds One 75-95 mph (65-82 kts) Two 96-110 mph (83-95 kts) Three 111-130 mph (96-113 kts) Four 131-155 mph (114-135 kts) Five 155+ mph (135+ kts)
Central Pacific Hurricane Center Watches and Warnings Hurricane/Tropical Storm Watch • Hurricane/Tropical Storm conditions are possible in the watch area…usually within 48* hours. Hurricane/Tropical Storm Warning • Hurricane/Tropical Storm conditions are expected within the warning area…usually within 36* hours * Change starting with 2009 season in Central Pacific.
Recipe for Tropical Cyclones • Sea Surface Temperatures • 80°F (26.5°C) over a large area • Weak Vertical Wind Shear • Low Level Disturbance • Region of upper level divergence/outflow
Effect of Vertical Wind Shear 40,000 ft/200 mb H H Typical cruising altitude of commercial airplane Heat Heat 5,000 ft/850 mb L L Surface
Tropical Cyclone Impacts • Extreme wind conditions Iniki: wind gusts greater that 150 mph Iwa: wind gusts greater that 120 mph • Flash Flooding Iniki: 8 to 10 inches over short time frame TD 1-C: 14+ inches upslope of Hilo • Storm Surge, High surf Iniki: 30 to 35 ft surf on Kauai, high water marks up to 25 ft, 3 to 4 ft storm surge Estelle: 10 to 20 ft surf even though closest passage was 120 nm south of Big Island.
Tropical Storm Kika 7-12 August 2008 • First and only tropical cyclone in Central Pacific Basin for 2008 • Peaked at minimal Tropical Storm strength • Remained Well South of Hawaiian Islands • No impacts to Hawaiian Islands and no significant impacts to other Pacific Islands
Factors Affecting Tropical Cyclone Forecasts for Central Pacific • El Nino (Warmer) – Possible Impacts • More Active Hurricane Seasons • Greater Chance of Late Season Hurricanes • La Nina (Cooler) and Neutral Conditions • Tendencies of Normal to Less Active Hurricane Seasons
Central Pacific Tropical Cyclones 5 Most Active Seasons for Period 1971-2008 Year TC H TS TD • 1994 11 5 3 3 (El Nino Year) • 1992 11 3 3 5 (El Nino Year) • 1982 10 4 6 0 (El Nino Year) • 1997 9 0 5 4 (El Nino Year) • 1985 8 4 2 2 (La Nina Year)
2009 Hurricane Season Outlook • 80% near to below normal season • Seasonal Forecast 3-5 Tropical Cyclones • 20% chance of above normal season • 6+ Tropical Cyclones if moderate-strong El Nino develops • Based Upon • The ongoing conditions of suppressed activity since 1995 • Near normal ocean temperatures and then development of El Niño or warmer than normal temperatures during the later part of the season. • Have to prepare same way regardless of outlook
Central Pacific Hurricane CenterText Products • Tropical Weather Outlook • Tropical Cyclone Discussion • Tropical Cyclone Forecast/Advisory • Tropical Cyclone Public Advisory • Hurricane Local Statements
Central Pacific Hurricane CenterTropical Weather Outlook • Issued 4 times daily during hurricane season – June 1 through November 30 • 4 AM, 10 AM, 4 PM, 10 PM HST • The Tropical Weather Outlook provides a summary of possible or anticipated tropical cyclone development and other areas of interest • Can give you several days “heads up” before a tropical cyclone actually develops
Preparedness – Now • Know safe evacuation routes and shelter locations • Emergency and evacuation kit • Food and drinking water for 5 to 7 days • Strengthen home • Material to protect windows and doors • Insurance policy • Other – pets, boats, etc.
Emergency Plans • Individuals/Families – 7 days • Continuity of Operations • Businesses • Gather information about hazards • Meet with your Company/family to create/review plans
Questions? National Weather Service 2525 Correa Road Suite 250 Honolulu, HI 96822-2219 973-5280 james.weyman@noaa.gov 271-6238 www.weather.gov/hawaii www.weather.gov/cphc