Weather Instruments:

thermometer - measures temperature of the air in farhenheit or celsius or kelvin.

hygrometer - measures humidity and dewpoint readings (moisture content in the air)

anomometer - measures wind speed in miles per hour or kilometers per hour or meters per second

rain gauge - measures amount of precipitation that falls over a period of time in the area

Barometer - measures air pressure in inches of mercury or millibars. it's an indication of a storm is coming if it is dropping.

Weather map symbols:

Cold Front - associated with precipitation (rain, thunderstorms, snow, sleet) followed by colder air

Warm Front - associated with spotty precipitation (usually drizzle or flurries/sleet/freezing drizzle) followed by warmer air

and clearing skies

Stationary Front - associated with slow moving rain/snow often lasts for days, many cloudy days.

Occluded Front - brings cloudy skies, cooler temperatures, and precipitation

High Pressure - anticyclone, air sinks away clockwise from high pressure and brings fair, nice dry weather.

Low Pressure - cyclone, air flows clockwise where air rises and creates bad weather, clouds, precipitation.

The Water Cycle, as dipicted by the US Geological Survey

dew point - temperature at which the air must cool to be 100% saturated with water molecules and vapor

humidity - amount of water vapor in the air

evaporation - Liquid water Turning from a liquid into a gas (vapor)

condensation - process by which water vapor turns into a liquid

front - an area where two different types of air masses collide

Atmosphere - The entire layer of air that surrounds the earth, made up of 78% Nitrogen, 21% oxygen, and 1% other gases.

Precipitation - any water or ice molecules that travel from a cloud in the atmosphere to the ground.

Types of precipitation:

Rain - water droplets that fall from a cloud and reach the ground in the form of liquid droplets.

Snow - Ice crystals that fall out of a cloud and fall through cold air molecules less than 32 degrees to the ground surface

Sleet - also called ice pellets, are ice crystals that fall out of a cloud with a cold layer, then enter a warmer layer and become

water droplets, then refreeze through a thick cold layer below 32 degrees well above the ground and form small

round ice pellets in the form of sleet.

Freezing Rain - water droplets that fall out of a cloud through a very thick warm layer above 32 degrees farhenheit, then freeze

on contact on surfaces such as the ground, metal objects, wood, bridges, trees, powerlines, anything that is below

32 degrees farhenheit at the grounds surface.

Hail - water droplets that usually form in a thunderstorm, that are carried back up inside the cloud many times, sometimes as much

as 6 or 7 times before it falls down to earth often forming layers of ice at its carried higher and higher into colder layers

of the atmosphere. By the time it reaches the ground surface, it can fall as small as 1/8 of an inch around pea sized hail,

all the way up to softball and baseball sized hail. The largest hail ever recorded was the size of grapefruits.

graupel - small, ice particle that falls as precipitation similiar to sleet and ice pellets, only it breaks apart easily when it hits the grounds

surface. Also known as a snow pellet or soft hail.

Virga - Precipitation that is falling, but does not reach the ground, due to very dry air at the surface of the earth.

Types of Clouds & how high in the Atmosphere they reside:

Weather Clouds:

altocumulus cloud - a mid level puffy looking cloud during fair weather

cumulus cloud - low-level puffy looking cloud during fair weather

cirrocumulus cloud - a high-level puffy looking cloud during fair weather

Cumulonimbus cloud - Turbulent cloud associated with a thunderstorm and/or heavy precipitation.

Stratus cloud - low hanging clouds usually associated with drizzle, fog, and dreary weather.

Cirrus - thin whispy clouds in the highest levels of the atmosphere, during fair weather but usually mean a front in 12

to 24 hours.

75% of all tornadoes occur in Tornado alley in the Central Part of the US from Texas to the Dakotas

Tornado warning is issued, go to the basement immediately or an interior room on the lower level of your home.

isobars - connect areas of equal barometric pressure and show meteorlogists where a storm will move.

lightning is the electric discharge between an area that is positively charged area also a negatively charged one.

Weather radar often called Doppler Radar helps meteorologists track the intensity, direction, speed, and movement of the precipiation.

psychrometer - a device that consists of two thermometers that is used to determine the wet bulb temperature (dew point), temperature

at which dew and condensation form.

Tornado - storm with winds swirling in a small area of extremely intense low pressure, often characterized by a funnel shaped cloud that

causes damage along its path. Tornado damage is measure by the revised Fajita scale (EF0 through EF5)

Hurricane - a cyclone associated with winds greater than 74mph. often form in the Alantic Ocean or Caribbean Sea ; eastern

Pacific Ocean. They often move north, northwest, or northeast from where it develops and usually creates extremely heavy rains,

mudslides, tornadoes, storm surge. When moving inland, hurricanes weaken into tropical storms and tropical depressions which

can lead to extensive flooding, similiar to what happend in the southern tier of New York when the remains of tropical storm Lee

on September 7, 2011 moved and stalled in the southern tier.