The flashcards below were created by user
on FreezingBlue Flashcards.
What are thunderstorms?
Thunder and lightning during a rain event. Heavy wind and rain and hail. Cloud type- cumulonimbus Warm humid air gets uplifted. Occur in midwest 60 days out of the year and south east 100 days.
What are the topologic feature that effect Thunderstorms?
Gulf of mexico-provide warm moist air.
Rockie Mountain-Block warm humid air from moving west.
Air Mass Thunderstorms
- Most common
- Front pulls up mT air
- Instability creates uplift
- Seasonal-Land warmer>water summer and spring
Stages of a Air Mass Thunderstorm
1-Cumulus Clouds-Air rising (warm and humid air) Updraft-heated at surface due to land being warmer than waters where it originated.
- 2-Mature Stage-Updraft, precipitation forms and begins to fall creating downdrafts.
- *Entrainment-creates void and surrounding air moves into cloud and with down drafts
- *Once rain starts updrafts cut off, force down drafts to get stronger.
3-Dissipating Stage (End) Downdrafts
What is a sever thunderstorms?
- 58 mph wind
- Hail-3/4 inches
- Posisibility of tornados
- Rapid Cooling
1) Air is not rising straight up: instead of sideways
2) Not all rain (downdrafts) cut off updrafts due to the angle of the updrafts.
3)Gust Fronts-downdrafts moving to the front of the storm front; build it outward; cold and windy
4)Forces updrafts to rise sooner and creates a developing cell.
5) Downdrafts lead to further development
What is a Squall Line?
Dry lines where strong thunderstorms occur 100-200 miles infront of the cold fronts.
What is supercell thunderstorm?
multiple storms combined; with air joining in, in different directions.
What is lightning?
First ice pellets
Second updrafts occur and downdrafts
Third movement of break ice pellets up and chargers moves to the top and a negitive charge to the bottom.
Fourth mini charge gets sent to charged grounds and then electricity travels downward.
What is thunder?
Lighning super heats air in a short period of time, creates thunder by creation of a sound wave.
What is a surface flow?
warm humid air
What is upper layer air?
Colder heavier air
What is unstable air?
Traps warm moist air on the surface.
What is a cold front?
Destroys capping layer, warm air burst up?
What is a tornado?
- Uncertainty regarding development
- Rotating column of air extending down from a cumulonimbus cloud.
- Funnel vs. Tornado
- Funnel-doesnt touch the ground
- Tornado-Touches the ground
- Rapid drop in pressure
- Condensation and dark clouds
- Invisible vs. dust and debris
- Avg Diameter-500-2000ft
- Avg Speed-30mph
- Avg Wind Speed-72-300+mph
- NE track
Can occur anytime of the year-more frequent during the spring and early summer.
Further north later in the seasons tornados occur
The Fujita Scale-Japanese scientist based on damage assement.
Heavy colder air that becomes part of the down drafts
Tornado related deaths
- Decreasing in tornado related deaths
- Increase in tornados being reported
- This occurs because the increase in technology and warning systems.
Where is Tornado alley?
Texas, Oklahoma and Nebraska
Highest Wind Speeds ever recorded
- 318 mph highest wind speed-instraments was destroyed after recording.
- Oklahoma City- only 3-5 people died
- 695 people killed
- On the ground 219 miles
- Occured at night
What is a Tropical Cyclones?
- Develop near equator(center of low pressure)
- Power source warm water
- 80 F prime temp
- Seasonality-late summer to fall
- Most destructive natural disaster
- Storm surge
- High winds
- Need warm water
- Do not form right on equator 5-20 N or S
- Do not cross equator
- No hurricanes on west coast
- 1-Tropical distrubances
- Little pressure gradience
- no rotation
- 2- Tropical or Easterly Wave
- Ripple in the tradewinds
- Piling up off warm, moist air-->low pressure
- Pressure applied -->curved air flow
- 3-Low Wind Shear
- Low level atmospheric winds or it will get destroyed
- 4-Divergence at the top
- Allows pressure to lower
- 5-Many tropical disturbances: few develop further
- Tropical depression 37>
Characteristics of a Hurricane
- 74< winds
- Towering cumulonimbus clouds
- Matual Hurricane= 350 miles in diameter
- Significant pressure drop
- Convergence at the surface and divergence at top
- Strongest wind speeds on the right side
What is a steering wind?
- Trade winds that determine where the hurricane goes
- Right side- Hurricane winds and steering winds are in the same direction/combine, strongest winds and storm surge.
- Left side- opposite direction
What is the anatomy of a hurricane?
- Eye center- air is decending- cloud free, calm area
- Eye wall- most intense rain, wind and most sever weather
- Spiral Bands- radiate outwards
Impacts of a Hurricane
- Storm surge- caused by winds pushing water
- Wind Damage-increase with altitude
- Inland flooding- 100s of miles
Life span- avg of a week