Air Masses and Fronts What is an Air
- Slides: 47
Air Masses and Fronts
What is an Air Mass? • Air masses are large bodies of air which have similar temperature and moisture characteristics. • Air masses form when air stays over a region (called the source region) for several days. • Air masses that form over water will be moist. • Air masses that form over land will be dry.
Latitude determines temperature Moisture determined by whether it forms over oceans or continents
c continental = dry A= Arctic P= Polar T= tropic m marine = moist
Continental Polar does not move west
Fronts – boundary that separates 2 air masses with different temperatures
Cold Front a. short-lived thunderstorms b. move faster than warm fronts
Warm Front – longer, steady precipitation
Stationary Front • A stationary front occurs when the air masses on either side of the front are not moving toward each other.
Counter clockwise rotation into Low Storm moves northeast due to prevailing winds
How Mid. Latitudes Lows (occluded fronts) Form Counter. Clockwise rotation
OCCLUDED FRONT Warm air mass gets caught between 2 colder air masses and is forced aloft
Occluded Front
Winds spiral clockwise out of the High and counterclockwise into the Low Fronts are low pressure – lousy weather After the front passes – happy weather
Weather Changes after Fronts Pass • 2 TOTALLY different air masses so a change in weather • Temperature changes • Wind direction changes • Wind velocity changes • Dew Point changes • Barometer falls when front approaches and rises after it passes
BRRR!
WINDS FLOW COUNTERCLOCKWISE IN TO THE LOW PRESSURE SYSTEM – RISING AIR WINDS FLOW CLOCKWISE OUT OF THE HIGH PRESSURE SYSTEM – SINKING AIR
Hurricanes – counterclockwise low pressure systems (lousy weather)
Weather in a High • Clockwise Rotation • Bright, Clear • Happy Weather
LAKE EFFECT - SNOW Box 9. 2
Thunderstorm Facts • At any given time there an estimated 2000 thunderstorms in progress, mostly in tropical and subtropical latitudes. - About 45, 000 thunderstorms take place each day • Annually, The U. S. experiences about 100, 000 thunderstorms. • About 16 million thunderstorms occur annually around the world! • The lightning from these storms strikes Earth about 100 times each second
Lightning • Within the thunderstorm clouds, rising and falling air causes turbulence which results in a build up of a static charge. The negative charges concentrate in the base of the cloud. • This first, invisible stroke is called a stepped leader. • As soon as the negative and positive parts of the stepped leader connect there is a conductive path from the cloud to the ground and the negative charges rush down it causing the visible stroke.
Tornadoes • Area of quickly rotating air associated with a thunderstorm • Some contain winds of over 300 miles per hour • They can be as small as a hundred yards wide or larger than a mile wide
Development of a Funnel
Damage
Severe Weather Warnings • Tornado, Severe Thunderstorm, and Flash Flood Warnings • Severe weather is occurring • If it is for your area, take shelter right away • Don’t leave shelter until warning has expired
Severe Thunderstorm Warnings • A thunderstorm with winds of 58 mph or greater • Penny sized hail or larger • Also contain lots of lightning • Stay inside • Keep off the phone • Don’t take a shower or bath • Stay away from windows
Tornado Warnings • • A tornado or funnel cloud has been detected Take shelter RIGHT AWAY!!! Get under something sturdy in your basement No basement? Go to a room that has no windows like a closet or bathroom • In mobile homes, leave them and go to a storm shelter if available or lie flat in a ditch
Where we get data • Weather Stations • Radar • Satellites
Doppler Radar
Next Generation Radar (Nexrad)
- What are middle-latitude cyclones?
- Air mass notes
- Air masses in north america
- Air mass source regions
- Two cold air masses converge on a warm air mass
- Whats an air mass
- Air masses & frontswhat is an air mass?
- Air masses & frontswhat is an air mass?
- A swirling center of low air pressure is called
- Air masses & frontswhat is an air mass?
- Air masses & frontswhat is an air mass?
- Air masses & frontswhat is an air mass?
- Fronts in geography
- Air fronts
- Characteristics of fronts
- Area of low pressure where air masses meet and rise
- Air masses form in the tropics and have low pressure
- Modern earth science
- Source regions for air masses
- How to draw warm and cold fronts
- Circulation of air masses
- Importance of air masses
- Characteristics of air masses
- Cyclogenesis occurs along the________.
- Continental polar symbol
- Air mass map
- Characteristics of air masses
- Weather depression
- What are the five types of air masses?
- What happens when 2 air masses meet
- Air masses
- Air masses
- Occluded front
- Warm front diagram
- Air masses
- Continental polar canadian air masses generally move
- Fronts and pressure systems
- Harvard university weather
- Hubungan air tanah dan tanaman
- Warm front animation
- Weather fronts symbols
- Types of drawer fronts
- Occluded front animation
- Four types of fronts
- Warm fronts
- Fronts ph school
- Fronts
- Warm front