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Most active Atlantic hurricane season of record - 28 tropical/subtropical storms ... Category 5 hurricanes had been observed in a single Atlantic season. ...
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Slide 1:What if Rita had hit here?
and other facets from the historic 2005 hurricane season Bill Read Meteorologist in Charge Houston-Galveston NWS
The 2005 Atlantic Hurricane Season A A G G C C G G B B J J S S D D E E I I F F H H K K L L M M N N O O P P R R T T V V W W A A B B D D Z Z E ESlide 2:Track chart of the storms of the 2005 Atlantic hurricane seasonTrack chart of the storms of the 2005 Atlantic hurricane season
Slide 3:SEASON HIGHLIGHTS
Most active Atlantic hurricane season of record - 28 tropical/subtropical storms* developed, breaking the old record of 21 set in 1933. Sixteen tropical/subtropical storms became hurricanes, breaking the record of 12 set in 1969. Seven of the hurricanes became major hurricanes. This included the first time that four Category 5 hurricanes had been observed in a single Atlantic season. Hurricane Wilma had the lowest minimum central pressure ever observed in an Atlantic hurricane - 882 mb. The central pressure of Wilma fell 88 mb in 12 hours. The Accumulated Cyclone Energy (ACE) for the season was 284% of median the highest value of record for an Atlantic hurricane season. *an additional unnamed subtropical storm was added after the season ended Some of the season highlights include 27 tropical storms of which 15 became hurricanes 7 major hurricanes including three (and perhaps 4) Category 5s - the first time of record this has happened in a single season Wilma had the lowest central pressure ever observed in an Atlantic hurricane 882 mb The Accumulated Cyclone Energy index for the season was 284% of median the highest value of record for an Atlantic hurricane seasonSome of the season highlights include 27 tropical storms of which 15 became hurricanes 7 major hurricanes including three (and perhaps 4) Category 5s - the first time of record this has happened in a single season Wilma had the lowest central pressure ever observed in an Atlantic hurricane 882 mb The Accumulated Cyclone Energy index for the season was 284% of median the highest value of record for an Atlantic hurricane season
Slide 4:SEASON HIGHLIGHTS
Seven landfalls in the United States, including Hurricanes Cindy, Dennis, Katrina, Rita, and Wilma along with Tropical Storms Arlene and Tammy. Hurricane Ophelia also struck the North Carolina coast, although the center stayed just offshore. Death toll near 1400, including around 1200 from Katrina in the United States - the deadliest U. S. hurricane since the Palm Beach-Lake Okeechobee hurricane of 1928. Additionally, a large area of disturbed weather affecting Central America at the time of Hurricane Stan may have caused 1000-2000 deaths. Total damage to property in the United States estimated near $100 billion - the costliest U. S. hurricane season of record. Katrina caused estimated damage of at least $75 billion, making it the costliest single hurricane in U. S. history. Track forecast verification indicates that the average NHC forecast errors at all times were near record low levels. Some of the season highlights include Death of near 1400, including 1200+ from Katrina in the U. S. Some of the season highlights include Death of near 1400, including 1200+ from Katrina in the U. S.
Slide 5:Most Intense Hurricanes
All Time Records This season has seen 3 of the most intense hurricanes on record
Why Was 2005 Such A Busy Hurricane Season? WARMEST SST IN THE TROPICAL ATLANTIC SINCE 1948 LOW-LEVEL CIRCULATION ANOMALIES FAVORED DEVELOPMENT/INTENSIFICATION IN THE WESTERN PART OF THE BASIN WHERE VERTICAL SHEAR WAS WEAK Hurricane Rita 18 - 26 September 2005 175 mph 897 mb Lowest pressure ever recorded in the Gulf of MexicoSlide 9:Track chart of Hurricane RitaTrack chart of Hurricane Rita
Rita Track Forecasts1200 UTC 19 SeptemberSlide 10:Upper left: Track forecast guidance for Rita at 1200 UTC 19 September. Lower right: Five day forecast track and error cone for Rita at 1200 UTC 19 September. Upper left: Track forecast guidance for Rita at 1200 UTC 19 September. Lower right: Five day forecast track and error cone for Rita at 1200 UTC 19 September.
Slide 11:Comment by high level officials: Next time we will give you longer to evacuate
Lesson not learned? Rarely will local officials have a forecast point and intensity at 5 days right on their area. The pressure for longer lead time is demographic rather than meteorologic. We are preparing for the next Rita.
Slide 12:Ernesto Advisory 6
Rita Track Forecasts1800 UTC 21 Sep 2005 Actual Track The models are NOT always correctSlide 13:Track forecast guidance for Rita at 1800 UTC 21 September. Track forecast guidance for Rita at 1800 UTC 21 September.
Slide 14:Lesson: Forecast uncertainty
The longer the lead time needed to take action the less certain the forecast track Growth in the coastal zone has forced decision making out in time as fast or faster than improvements in the skill of track forecasting Most decisions need to be made with less than 50% confidence in occurrence of event for some case less than 20%
Slide 15:Evacuation decisions for Rita
Timeline created Tuesday PM assuming no change in forecast for landfall near upper coast late Friday/early Saturday onset of adverse conditions Friday afternoon at the coast Special Needs leave during day Wednesday Galveston County mandatory begins Wednesday evening after 6 pm for lowest areas Next zones to follow later that night and Thursday
Slide 16:Wake up Advisory Wednesday Morning Cat 3 forecast to Cat 4
Slide 17:Actions on Wednesday
Wake up forecast almost a worse case scenario Most people in evacuation zones started moving during the day on Wednesday up to 12 hours before mandatory kicked in. Texas Gov and many local officials call for evacuation by all people in path of the storm. At this time that meant anywhere from south of Corpus Christi through Beaumont - Port Arthur. And they did!... mass exodus underway by early afternoon. By Thursday night evacuation was mostly over.
Slide 18:Ritas Legacy for Houston Galveston Area
Slide 19:Ad hoc contra flow on I45 near the Woodlands
Slide 20:Lesson on evacuation- Katrina effect?
Recent evacuations from Florida, the East Coast and even LA/MS show 70-80% of people ordered to evacuate do so, and only 10-15% of total evacuees were from outside evacuation zone. 85-90% of people ordered to leave for Rita did so Over half of evacuees were from outside evacuation zone.
Slide 21:What if Rita came further west?Based on Wednesday PM forecast
Slide 22:Possible peak gusts from a cat 4 on worst case track for Rita
Slide 23:Expected Storm Surge
Houston-Galveston Study Area Mean Sea Level HOUSTON Texas City Galveston La Porte League City Alvin Baytown HOUSTON Texas City Galveston La Porte League City Alvin Hurricane Carly 9/11 at 1500 CDT MEOW NW at 8 MPH Surge: 22.4 Feet Baytown Bills old house Bills new house NWSSlide 27:Other Lessons Katrina and Rita
About 4 out of 5 homeowners flooded by surge and/or levee failure did not have nor were they required to have flood insurance Lesson not yet learned almost every big storm surge event yields similar insurance statistics and debates We only prepare for the 100 year event which at best is a low end category 3 Is this wise? MS/LA rebuilding to at best a category 3 level of protection expect a similar disaster sometime in the future
13 5 2 Dr Grey* *Dr Grey update as of 1 Sep 2006 NOAA outlook as of 1 Aug 2006Slide 29:Sea Surface Temperature Anomaly9/2/06
Slide 30:2006 Six Tropical Storms through 9/7 - about normal through Sep 7
48%
Slide 31:Thank You!
bill.read@noaa.gov www.srh.noaa.gov/hgx www.weather.gov