Final- Thunderstorms

Dust Whirl Stage

From the surface, short funnel extends and swirls upward from a thunderstorm.

Mature Stage (Tornado)

Most severe stage of a tornado; funnel reaches greatest width and is most vertical.

Shrinking Stage (Tornado)

Funnel shrinks and tilts; damaged area narrows.

Decay Stage (Tornado)

Rope-shaped, very distorted tornado stage.

Thunderstorm Needs

Rising air, moisture, and instability.

Cumulus Stage (Thunderstorm)

Updrafts are present.

Mature Stage (Thunderstorm)

Starts to precipitate and is the most intense stage.

Dissipating Stage (Thunderstorm)

Downdrafts are present.

Severe Storm

Hail, surface winds exceeding 50 knots, and/or tornadoes.

Ordinary Cell/Airmass T-storms

Forms away from fronts, predictable, less than an hour, less severe, and where steep winds converge.

Multicell

Multiple convection cells all in different stages with possible gust front, microbursts, overshooting top, mammatus clouds, mesohigh, shelf cloud, and roll clouds.

Squall Lines

Active line of storms on or ahead of a cold front.

Rear inflow jet

Strong straight winds, also known as "derecho".

Mesoscale Convective Vortex

Circular T-Storms, HUGE, Long-lived, summer.

Supercell

One updraft, strong wind shear, outflow never cuts, can spin, huge hail possible.

Tropical Disturbance

Forms over North Atlantic or Pacific. Sfc winds converge, warm water, high humidity, no high wind shear.

Tropical Depression

Surface winds between 22-34 knots.

Tropical Storm

Surface winds between 35-64 knots.

Hurricane

Surface winds equal to or greater than 65 knots.

Hurricane (Northeast Movement)

Eastern side is strongest; experiences storm surge on the north.

Eye (Hurricane)

Has low pressure, smaller, and strong winds.

Initial Stage (Mid-Latitude Cyclone)

Cyclonic windshear with cold air and warm air.

Frontal Wave (Mid-Latitude Cyclone)

Forms the cold front pushes south and the warm front pushes north.

Open Wave (Mid-Latitude Cyclone)

Developed more, lower pressure, strong cyclonic flow.

Mature Stage (Mid-Latitude Cyclone)

Cold front catching up to warm front, warm sector squeezed; system becomes occluded, very intense.

Advance Occlusion (Mid-Latitude Cyclone)

Cold air on both sides; storm begins to die.

Low Pressure

Unstable; showery.

High pressure

Stable; steady.

Bergeron Process

Raindrop to ice crystal; a mix of liquid and ice particles.

Frost Point

Temperature at which saturation occurs, but straight to ice.

Dew Point

Temperature at which saturation occurs.

Polar Low vs Hurricane

Both form over water; polar lows produce snowstorms, and hurricanes produce rainstorms.

Stable Conditions

Stable condition that resists vertical motions, produces nice weather and inversions.

Unstable Conditions

Unstable condition that produces bad weather and rising air.

Troposphere

Weather occurs here. Gets colder as you go up.

Stratosphere

Ozone layer is here; gets warmer as you go up (inversion).

Radiation Inversions

Calm, cool, clear nights.

Squall Line

Row of thunderstorms with gusty winds; forms with cold fronts, generally ahead of them.

Lightning

Lightning forms in thunderstorms; a discharge of electricity.

Mountain Breeze

Cool air sinking down mountains (night).

Valley Breeze

Warm air rising up mountains (day).

Land Breeze

High overland.

Sea Breeze

High over sea.

Advection

West to East flow.

Accumulation

Supercooleddrops colliding to make nail.

Conduction

Helpful for heat transfer, where heat is transferred by touch/molecule to molecule.

Convection

Heat transfer by vertical air.

Advection

Heat transfer by horizontal air.

Shelf Cloud

Warm, moist air that rises along a thunderstorm gust front.