Chapter 25

Weather

Weather is largely controlled by the AIR MASSES that are prevalent

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1. The air masses are named after the source region of the air mass.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation.

2. The air masses are also named after the latitudes they come from.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation.

2.The air masses are also named after the latitudes they come from.a. Polar means from the poles, and it is cold.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation.

2.The air masses are also named after the latitudes they come from.a. Polar means from the poles, and it is cold.b. Tropical means it is from the tropics, and it is warm

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation.

2.The air masses are also named after the latitudes they come from.a. Polar means from the poles, and it is cold.b. Tropical means it is from the tropics, and it is warm.c. This is the capital letter in the abbreviation.

Weather is largely controlled by the AIR MASSES that are prevalent. In the Northern American continent, there are seven major air masses.1.The air masses are named after the source region of the air mass.

a. Continental means it formed over a continent, and is dry.b. Maritime means it formed over a sea or ocean, and it is wet.c. These are small letters in the air mass abbreviation.

2.The air masses are also named after the latitudes they come from.a. Polar means from the poles, and it is cold.b. Tropical means it is from the tropics, and it is warm.c. This is the capital letter in the abbreviation.

3. There can be a third (optional defining) part of the mass name.

Try these for your practice!!!!

cT means Continental Tropical and it would be dry and warm

mP __________________ ___________________

mT __________________ ___________________

cP __________________ ___________________

mPAtlantic__________________ ___________________ from _____________

mTGulf __________________ ___________________ from _____________

mPPacific __________________ ___________________ from _____________

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.1. Cold Front ~ this is when cold air overtakes warmer air and pushes it up.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.1. Cold Front ~ this is when cold air overtakes warmer air and pushes it up.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.1. Cold Front ~ this is when cold air overtakes warmer air and pushes it up.

The rising air cools quickly as it forms violent storms and tornadoes.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.1. Cold Front ~ this is when cold air overtakes warmer air and pushes it up.

The rising air cools quickly as it forms violent storms and tornadoes.

This line of heavy thunderstorm activity is called a squall line. This can often actually be seen on large lakes or open fields.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.2. Warm Front~ is when a mass of warm air overtakes a cold air region.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.2. Warm Front~ is when a mass of warm air overtakes a cold air region.

The air rises gently over the course of a couple of days, and produces long periods of light to moderate precipitation. This is what is known as a warm summer rain.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.2. Warm Front~ is when a mass of warm air overtakes a cold air region.

The air rises gently over the course of a couple of days, and produces long periods of light to moderate precipitation. This is what is known as a warm summer rain.

The clouds are layered, without “fluffy” stuff

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.3. Stationary front ~ is when two fronts “bump up” against each other, and neither one will budge. The weather is really similar to warm front, with days of clouds and mild rains.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.4. Occluded Fronts ~ are when a fast moving cold front meets another cool front, and lifts the warm air mass completely off of the ground.

Fronts are when one air mass overtakes another.There are five (5) types of fronts that we will examine.5. Polar Fronts ~ are huge cold air fronts that sit between 40º and 60º. This is often called the “jet stream” front.

Air that is moving in a counter-clock direction is called “cyclonic”, and if it is moving in a clockwise direction it is called “anti-cyclonic”.

Severe weather1. Hurricanes (typhoons in Pacific)

Severe weather1. Hurricanes (typhoons in Pacific)

A self feeding process. Warm water is the primary source for the energy in a hurricane.

Severe weather2. Thunderstorms

First stage (Cumulus Stage) is when the storm is building, and clouds are growing. Almost all air is going “up”.

Severe weather2. Thunderstorms

When mature, the amount of “up” air equals the “downward” air. Heavy rain and hail.

Severe weather2. Thunderstorms

In the dissipating stage, the downward movement of air is dominant, and the storm dies. A dissipating storm will, however, often help a new cumulus stage form.

Tornadoes are the most violent of storms (but not the most destructive).1.There is a “tornado alley” in the U.S.A. where cP and mT air mix.

Tornadoes are the most violent of storms (but not the most destructive).1.There is a “tornado alley” in the U.S.A. where cP and mT air mix.2.Tornadoes over water are called water spouts

Tornadoes are the most violent of storms (but not the most destructive).1.There is a “tornado alley” in the U.S.A. where cP and mT air mix.2.Tornadoes over water are called water spouts3.Very rare winter tornados (of which Mr. Monroe has seen one) are called white tornadoes because they pick up snow.

Weather Instruments

Thermometers1. Liquid Thermometer ~ which acts because liquids expand when heated

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates3.Electrical thermometers ~ which act because electricity flows at different rates through metals at different temperatures.

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates3.Electrical thermometers ~ which act because electricity flows at different rates through metals at different temperatures.Aneometers1. Wind speed is measured with a simple cone assembly

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates3.Electrical thermometers ~ which act because electricity flows at different rates through metals at different temperatures.Aneometers1.Wind speed is measured with a simple cone assembly2.Wind direction is measured with …….

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates3.Electrical thermometers ~ which act because electricity flows at different rates through metals at different temperatures.Aneometers1.Wind speed is measured with a simple cone assembly2.Wind direction is measured with …….Upper Air Conditions1. RADAR is used (must be particles in air to measure speed of)

Weather Instruments

Thermometers1.Liquid Thermometer ~ which acts because liquids expand when heated2.Bimetal thermometer ~ which acts because different metals expand at different rates3.Electrical thermometers ~ which act because electricity flows at different rates through metals at different temperatures.Aneometers1.Wind speed is measured with a simple cone assembly2.Wind direction is measured with …….Upper Air Conditions1.RADAR is used (must be particles in air to measure speed of)2.Radiosonde may be used, but they are old, cumbersome and usually not used by weathermen. It is a balloon filled with helium that carries instruments.

Weather can be forcasted.Days 1-3 are usually pretty accurate

Weather can be forcasted.Days 1-3 are usually pretty accurate

Days 3-7 are usually following the daily trend. After that, the weather forecast is going to follow the seasonal trend.

Controlling the weather

The only people to control the weather was a gang of evil people on the soap opera “General Hospital”.

It has never worked, even though people have seeded clouds, shot cannons of rice, and other things. Weather cannot be controlled by man.

Controlling the weather

The only people to control the weather was a gang of evil people on the soap opera “General Hospital”.

It has never worked, even though people have seeded clouds, shot cannons of rice, and other things. Weather cannot be controlled by man.

Climate can be controlled by man.