ch. 11 hurricanes

eye of a hurricane

circle in the center of a hurricane

typhoon

alternative name for a hurricane

Hurricane

low pressure system that forms over warm ocean waters, between latitude 5° and 20°

Hurricane characteristics

Most powerful of all storms, Sustained winds of 74 mph, always grow from preexisting disturbace

what do hurricanes never do?

Cross the equator

hurricane origin

An easterly wave- a long but weak migratory low-pressure system in the tropics between 5° and 25° of latitude

stage 1

Tropical disturbance

stage 2

tropical depression

stage 3

tropical storm (name given at this stage)

stage 4

Hurricane

Steps in the formation of hurricanes

tropical disturbance, tropical depression, tropical storm, hurricane

Warm ocean water

must be at least 81°F

Hurricane structure

eye, eye wall, cloud/rain bands, circulation pattern

The eye

Region of sinking air, average diameter about 15 mi

The eye wall

strongest region of storm, doubled eye wall- could develop as rain bands contract

Hurricane forcasts and advisories

National Hurricane Center

hurricane intensity scale

Saffir-Simpson Scale (1-5)

hurricane decay

when it reaches land, or when the ocean becomes cold

which side of the hurricane is weaker?(Northern hemisphere)

left

which side of the hurricane is weaker?(southern hemisphere)

right

Hurricane Destruction

wind, heavy rain, tornadoes, storm surge, rise in water level associated with pressure drops

summarize katrina video!

extra credit

deadliest hurricane in the us

galveston, TX 1900, 8000+ deaths

Quantitative Forcast

1 inch of snow

Probability Forcast

30% chance of rain

Qualitative Forcast

cloudy/partly cloudy

Short-range forcast

48hrs

medium-range forcast

3-7 days

long-range forcast

Beyond 7 days, no time limit

nowcasting

shortest forcast range- extends up to 6hrs

Synoptic Map (Traditional surface map)

shows conditions at a specific time