Overview of the 2006 Atlantic Hurricane Season

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Overview of the 2006 Atlantic Hurricane Season
Richard D. Knabb, Daniel P. Brown, and James L.
Franklin
National Hurricane Center
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2006 ATLANTIC HURRICANE SEASON STATISTICS 2006 ATLANTIC HURRICANE SEASON STATISTICS 2006 ATLANTIC HURRICANE SEASON STATISTICS 2006 ATLANTIC HURRICANE SEASON STATISTICS 2006 ATLANTIC HURRICANE SEASON STATISTICS 2006 ATLANTIC HURRICANE SEASON STATISTICS
NAME DATES MIN. PRESS (MB) MAX. WINDS (MPH, SSHS) DIRECT DEATHS U.S. DAMAGE ( million)
TS ALBERTO 10-14 JUN 995 70 0 minor
TS UNNAMED 17-18 JUL 998 50 0 0
TS BERYL 18-21 JUL 1000 60 0 minor
TS CHRIS 1-4 AUG 1001 65 0 0
TS DEBBY 21-26 AUG 999 50 0 0
H ERNESTO 24 AUG1 SEP 985 75 (1) 5 500
H FLORENCE 3-12 SEP 974 90 (1) 0 0
H GORDON 10-20 SEP 955 120 (3) 0 0
H HELENE 12-24 SEP 955 120 (3) 0 0
H ISAAC 27 SEP2 OCT 985 85 (1) 0 0
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2006 Season Summary

• Ten tropical storms formed, five of which became
  hurricanes, including two major hurricanes
• Close to the long-term averages of 11, 6, and 2
• Fewest tropical storms since 1997 (8)
• Fewest hurricanes and major hurricanes since 2002
  (4 and 2)
• The Accumulated Cyclone Energy (ACE) index for
  the season was about 90 of the long-term median
• Lowest ACE value since 2002, and third lowest in
  last ten years (ahead of 1997 and 2002)
• Four hurricanes formed in September, which is
  above the long-term average of 2.5
• Demise of Isaac as a tropical cyclone on 2
  October ties 2006 (with 1982) for the
  third-earliest end of season in the satellite era
  (behind 1993 and 1983)

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2006 U. S. Impacts

• Three tropical storms made landfall in the United
  States
• TS Alberto made landfall along the Florida Gulf
  Coast big bend area in June impacts were limited
• TS Beryl passed over Nantucket, Massachusetts
  with minimal impacts
• Ernesto made three separate U.S. landfalls as a
  tropical storm middle Florida Keys, southern tip
  of the Florida peninsula, and southeastern North
  Carolina
• Approx. 500M U. S. property damage, mostly due
  to floods
• Two fatalities in Virginia, but not directly due
  to Ernesto as a tropical cyclone
• No landfalling U.S. hurricanes for first time
  since 2001

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2006 International Impacts

• Ernesto caused floods and mud slides in Haiti and
  the Dominican Republic, causing 5 fatalities in
  Haiti impacts in Cuba were very limited.
• Hurricane Florence passed just west of Bermuda,
  causing hurricane-force winds there. After
  becoming extratropical, Florence brought
  hurricane-force winds to portions of Newfoundland
  that produced considerable damage.
• Gordon was the first hurricane to affect the
  Azores since 1991.
• Isaac brushed Newfoundland, producing winds of
  tropical storm force over the southeastern
  portion of the Avalon Peninsula.

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70 mph
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Alberto Rainfall
Figure courtesy NOAA/HPC
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Storm Surge from Alberto
Steinhatchee, FL
7 ft surge at Crystal River Power Plant
Photos Courtesy of NWS WFO Tallahassee
Horseshoe Beach, FL
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Images of Alberto
June 11 MODIS
June 12 MODIS
June 13 MODIS
June 12 - 91 GHz Composite Near Peak Intensity
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Impacts of Alberto
Venice, Florida Joe Raedle, Getty Images
Lote Seco, Cuba Jorge Rey, AP
Sarasota, Florida Joe Raedle, Getty Images
Crystal River Chris OMeara, AP
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Flooding inNorth Carolina and Virginia
Raleigh, NC
Raleigh, NC
Courtesy of NWS WFO Raleigh
Courtesy of NWS WFO Raleigh
Raleigh, NC
Courtesy of NWS WFO Raleigh
Stephen M. Katz, The Virginian-Pilot
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50 mph
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60 mph
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65 mph
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50 mph
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985 mb
75 mph
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August 27 MODIS
August 30 MODIS
August 29 MODIS
September 1 MODIS
September 1 MODIS
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Ernesto Rainfall
Figure courtesy NOAA/HPC
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Impacts of Ernesto
Wilmington, NC AP
3 ft surge at Wrightsville Beach, NC, Indirect
surge in Chesapeake Bay.
AP
David Bently Wilmington, NC Star News
Goldsboro, NC Mitch Loeber, AP
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Ernesto Florida Landfall
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Ernesto North Carolina Landfall
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OBSERVED 5-DAY POSITION
OBSERVED 3-DAY POSITION
TRACK GUIDANCE OUT TO 5 DAYS TROPICAL STORM
ERNESTO, 8/26/06 1200 UTC
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974 mb
90 mph
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Images of Florence
September 13 MODIS
September 11 MODIS
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Impacts of Florence
Bermuda AP
Bermuda AP
Francois, Newfoundland CBC News
Hamilton, Bermuda Carleton Hall, Reuters
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120 mph
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120 mph
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Images of Helene and Gordon
September 17 MODIS
September 18 MODIS
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85 mph
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Vertical wind shear generally weaker than average
Stronger
Weaker
Tropical storm genesis points during
August-October 2006
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ASO Sea-Surface Temperature Anomalies in the
green box were the second warmest since 1930.
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Rapid El Niño warming after early August forecast

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Rising
Sinking
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Instability over the tropical Atlantic Ocean and
Caribbean Sea was less than average during the
hurricane season (figures courtesy CIRA)
Troposphere over Tropical Atlantic Ocean and
Caribbean Sea was more stable than average
(figures courtesy CIRA)
Unstable
Unstable
Stable
Stable
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Middle to upper troposphere over the Tropical
Atlantic Ocean and Caribbean Sea was drier than
average (figures courtesy CIRA)
Dry
Dry
Moist
Moist
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500 mb Height Anomalies September 2005 vs.
September 2006
H
L