Tropical CyclonesChapter 11Meteorology 1010Professor BundsUtah Valley University

Tropical Cyclone Naming, Paths and Seasonstyphoonshurricanescyclones

Paths of All Tropical Cyclones 1985 - 2005

Hurricane Air Flow

Upper Level Hurricane Air Flow

Hurricane Rankings

Saffir-Simpson CategoryMaximum sustained wind speedMinimum surface pressureStorm surgemphm/sktsmbftm1 74-95 33-4264-82greater than 9803-51.0-1.7 296-110 43-49 83-95979-9656-81.8-2.6 3111-130 50-58 96-113964-9459-122.7-3.8 4131-155 59-69114-135944-92013-183.9-5.6 5156+ 70+ 136+less than 92019+5.7+

Hurricane FormationPowered largely by warm waterHurricanes are most common late summer to fall hurricane seasonVaries by regionWeaken over landUsually weaken as they approach coastline alsoForm near but not over equator, given proper conditions (next slide)

Ingredients for Hurricane FormationWarm water at least 80oFRelatively cool air at altitudeRelatively moist air at moderate altitude (3 miles up)At least 300 miles from the equatorLittle wind shear between surface and upper air (6 miles up)Divergence aloftA trigger e.g., big thunderstorms

Hurricane HazardsStorm SurgeOn average, the biggest threat to life and propertyWindsFlooding from extreme precipitationCan cause major problems far inland

Galveston Hurricane, 1900> 10,000 fatalities,worst natural disaster in U.S. history

Storm Surge

Tropical Cyclone Winds & Storm Surge

Hurricane Ike Storm SurgeSeptember 2008

Hurricane Ivan10 am FridayLink to visible loop

Hurricane Ivan10 am FridayLink to visible loop

Hurricane Ivan 1:45pm Thursday

Hurricane Ivan 1:45pm Thursdaylink to infrared loop

Hurricane Ivan 9:45pm Fridaylink to infrared loop

Hurricane Ivan 9:45pm Fridaylink to infrared loop

Link to visible loopLink to IR loop

Ivan, 9.15.04 11:15 am EDT

Ivan, 9.15.04 10:45 am EDT

Mississippi Delta

Mississippi River DeltaActive Lobe~ 500 years oldMississippi wants to follow course of Atchafalaya River

Ivan, 9.17.04 4:15 pm EDT

Hurricane Ike Storm SurgeSeptember 2008

Path of hurrican and locations of tidal gauges that recorded storm surge, as shown on following slides

This and following photos are of Galveston, TX, and nearby areas

Houston, TX

High Island, Texas

Gilchrist, Texas

Orange, Texas