PAF 261 Independent Study Terms

girl why this program apparently 8-9 hours long?

synoptic scale

used to describe events where weather patterns affect one or several states

mesoscale

used to describe smaller and shorter-term weather events

tight pressure gradient

used to refer to a rapid pressure change between two areas

front

used to refer to the boundary between different air masses

cold front

leading edge of an advancing cold air mass; often initiate thunderstorms and produce hazardous winter conditions

warm front

the edge of an advancing warm air mass; generally brings steady precipitation

stationary front

occurs when a front stops moving and neither air mass is replacing the other; usually causes long-lasting precipitation

occluded front

a front where one section of the front begins to move as a warm front while the other section moves as a cold front

dryline

a boundary that separates dry and moist air

convergence

a term that describes a situation where winds from different directions or have different speeds meet

thermals

parcels of air that rise like bubbles when the Sun’s energy heats the Earth’s surface

temperature inversion

occurs when a layer of warmer air lies above colder air

direct measurements

include ships and aircraft that have sensors that directly measure temperature, pressure, moisture, and winds

indirect measurements

used to refer to those from satellites, radars, wind profilers and other sensors that measure a quantity used to infer something about another parameter

outlook

intended as an advance notice to heighten awareness and to prompt people to begin taking some kind of action

watch

issued when there is an increased chance of a hazardous event and indicates the need for vigilance on a civilian’s part to stay up-to-date on the weather situation

advisory

issued once a threat has materialized; indicates situations that are hazardous but not necessarily life-threatening

warning

issued once a threat has materialized; used for life-threatening situations

storm surge

an abnormal rise of water generated by a storm’s winds

seiche

caused by winds that push lake water to one end of the lake

snow squall

a period of moderate to heavy snowfall; intense but of limited duration, accompanied by strong, gusty surface winds and possibly lightning

Hawaiian

type of volcanic eruption that produces little volcanic ash

Strombolian

type of volcanic eruption that is short-lived and the ash is not ejected to great heights

Vulcanian

type of volcanic eruption that produces large quantities of ash that can be dispersed for miles downward

Plinian

type of volcanic eruption that produces large quantities of ash that can be ejected high into the stratosphere and circle the globe