Understanding Fronts

Draw this table in your notes: Name of FrontSymbol (need red, blue, & purple) Associated Weather/Clouds Cold Warm Stationary Occluded

What is a Front? Front - the boundary between two masses of air of different temperatures Front - the boundary between two masses of air of different temperatures

Cold Front Marked on a map with a blue line and blue triangles pointing towards the warm air. (in the direction the cold air is going.) Marked on a map with a blue line and blue triangles pointing towards the warm air. (in the direction the cold air is going.) Associated with cumulus & cumulonimbus clouds ahead of the front in the warm air, producing showers and thunderstorms. AFTER the cold front, the sky is clear. Associated with cumulus & cumulonimbus clouds ahead of the front in the warm air, producing showers and thunderstorms. AFTER the cold front, the sky is clear.

Cold Front Simple 3-D idea: Simple 3-D idea:

Cold Front

Cold Front and Warm Fronts

Warm Front Marked on a map by a red line with red semi-circles pointed towards the cool air (in the direction the warm air is going.) Marked on a map by a red line with red semi-circles pointed towards the cool air (in the direction the warm air is going.) Generally associated with stratus type clouds, overcast skies, fog, and general rain or snow. Generally associated with stratus type clouds, overcast skies, fog, and general rain or snow.

Warm Front Simple 3-D idea: Simple 3-D idea:

Warm Front

Cold Front and Warm Fronts

Stationary Front Marked by alternating blue lines & blue triangles (pointed in the direction of the warmer air) and red lines & red semi- circles (pointed in the direction of the cooler air) Marked by alternating blue lines & blue triangles (pointed in the direction of the warmer air) and red lines & red semi- circles (pointed in the direction of the cooler air) Usually associated with multiple days of clouds and precipitation Usually associated with multiple days of clouds and precipitation

Occluded Front Marked by a purple line with alternating purple triangles and purple semi-circles, all pointing in the direction of the frontal movement. Marked by a purple line with alternating purple triangles and purple semi-circles, all pointing in the direction of the frontal movement. Type of weather = sometimes thunderstorms, but often weather clears Type of weather = sometimes thunderstorms, but often weather clears

Occluded Front Simple 3-D idea: Simple 3-D idea:

Occluded Front

Clouds A brief guide on clouds types, cloud observing, and time.

Have you ever looked at clouds and wondered if they had names? Luke Howard did over 200 years ago. Luke Howard did over 200 years ago. He decided that clouds could be classified into three main categories. He decided that clouds could be classified into three main categories. He used Latin to name the clouds. He used Latin to name the clouds.

Cirrus StratusCumulus **Draw this on the other side of your sheet

Three main cloud types Cirrus (Latin for Curl) Cirrus (Latin for Curl) –means hair and describes wispy looking clouds. This term is also used to describe high level clouds Cumulus (Latin for heap) Cumulus (Latin for heap) –means pile and describes heaped, lumpy clouds Stratus (Latin for layer) Stratus (Latin for layer) –means layer and describes clouds that form in sheets and do not have any unique features

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball)

You’ve learned the basic types of clouds…let’s get go on to deluxe clouds. Nimbus (Latin for Rain) Nimbus (Latin for Rain) –use this term only when a cloud actually produces precipitation Alto Alto – describes mid-level clouds Pictures from

Let’s combine names. Cirrocumulus Cirrocumulus –Can best be described as a high cloud that resembles fish scales

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale)

Stratocumulus Stratocumulus –Best described as a cloud accident or puffy bottoms Let’s combine names.

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale) Stratocumulus (Puffy bottoms, cloud accident)

Nimbostratus Nimbostratus –Looks like a stratus cloud but it is producing precipitation Let’s combine names.

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale) Stratocumulus (Puffy bottoms, cloud accident) Nimbostratus (low blanket with lots of rain)

Altocumulus Altocumulus – Mid-level cloud –Described as flocks of sheep or streets of clouds Let’s combine names. Altostratus Altostratus –Mid-level cloud –Light gray layer –Light behind the clouds Pictures from

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale) Stratocumulus (Puffy bottoms, cloud accident) Nimbostratus (low blanket with lots of rain) Altocumulus (Streets of clouds, flock of sheep) flock of sheep) Altostratus (Light grey, light behind clouds)

Let’s combine names. Cirrostratus Cirrostratus –High-level cloud –Thin veil of clouds –Produces a sun or moon halo

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale) Stratocumulus (Puffy bottoms, cloud accident) Nimbostratus (low blanket with lots of rain) Altocumulus (Streets of clouds, flock of sheep) Altostratus (Light grey, light behind clouds) Cirrostratus (Thin, veil,sun/moon halo)

Let’s combine names. Cumulonimbus Cumulonimbus Thunderclouds Storm makers Produce lightening and thunder

(Wispy, Horse tail) Cirrus Stratus (Layered, Flat) Cumulus (Cotton Ball) Cirrocumulus (Fish Scale) Stratocumulus (Puffy bottoms, cloud accident) Nimbostratus (low blanket with lots of rain) Altocumulus (Streets of clouds, flock of sheep) Altostratus (Light grey, light behind clouds) Cirrostratus (Thin, veil,sun/moon halo) Cumulonimbus (Thunderstorm clouds)

LET’S OBSERVE! - What cloud types are present? - What’s the percentage of cloud cover? - How much light penetrates the clouds?