Tuesday 29 January 2013

Common Weather Folklore and Proverbs


1 .When sea birds fly to land
there truly is a storm at hand.

Comment: I see no problem in taking seabirds' lead.
 
2. To talk of the weather is nothing but folly; when it rains on the hill, it suns in the valley.
 
 
3. From twelve ‘til two tells what the day will do.
 
4. The more rain, the more rest;  
fair weather’s not always best.
comment: the glass is half full.
 
 
5. Yellow streaks in sunset sky,  wind and day long rain is nigh. 
 
 6. Year of snow , fruit will grow.

 

 Comment: Only if there is

 no flooding.
 

7. The chill is on, near and far,       
in all the months that have an ‘R’.
 
comment: it is true for the residents of Saskatchewan.
 
 

8. Rainbow in the east, sailors at peace. Rainbow in the west sailors in distress.


 
 
    




 Comment:
Yes! The storm has moved on to the East.



 
9. Rainbow in the morning, shepherds take
 warning; rainbow at night, shepherds’ delight.
 
 
 
10.  A sunshiny shower won’t last half an hour.
 

Acknowledgement:

These proverbs are taken from the following website.

http://www.weatherwizkids.com/weather-folklore.htm


 

 
 
 
 
 

Meteorology and Weather Prediction



 
Radar and Satellite Technology:
Radars
The word radar is an acronym from "Radio Detection and Ranging". Radar images are useful for locating precipitation.
A radar sends a pulse of energy into the atmosphere and if any precipitation is intercepted by the energy, part of the energy is scattered back to the radar. These returned signals, called "radar echoes", are assembled to produce radar images.
 
Sending and Receiving Signals  (detecting a target)
                                                              
     
The radar creates an electromagnetic energy pulse which is focused by an antenna and transmitted through the atmosphere. Objects in the path of this electromagnetic pulse, called targets, scatter the electromagnetic energy. Some of that energy is scattered back toward the radar.
 
 

The receiving antenna (which is normally also the transmitting antenna) gathers this back-scattered radiation and feeds it to a device called a receiver.
 






 
 
The location of the colored radar echoes indicate where precipitation is falling and the various colors indicate the intensity of the precipitation through the color code in the lower left corner of the image.
 
 



Satellites:

A satellite is defined as a man-made object put into orbit around a celestial body, like the earth or the moon.

Satellites serve a wide variety of purposes from transmission of television signals via communication satellites to guidance and tracking systems of defense satellites. For meteorologists, satellites provide a comprehensive view of the world's weather. On April 1, 1960, the first weather satellite was launched into orbit from the United States. Since then, weather satellites have been launched into orbit and their capabilities have improved significantly. Satellites carry imager and sounder instruments enabling them  to image clouds, monitor earth's surface temperature and water vapor fields, and sound the atmosphere for its vertical thermal and vapor structures. Today, not only do satellites observe clouds, but measure other non- visible radiation from the earth and atmosphere. This helps us to estimate such aspects as crop and soil conditions.
 
Acknowledgement: The above information is taken from the following website:

 

Environment Canada's Radar and Satellite imagery:

Canadian Weather Radar               

 

 

Satellite Images

 
 
http://www.weatheroffice.gc.ca/satellite/index_e.html

Sunday 27 January 2013

 
 
Weather Fronts/Systems
 

 Warm Front

A front can best be described as the border between two different air masses. A warm front is the leading edge of a milder or warmer air mass. A warm front travels in such a way that it results in warm air replacing colder air. This happens as the warm air rises up and over the cold air below. As the warm air travels upwards, it begins to mix with the cold air aloft and condenses to form clouds. You can usually expect periods of rain or drizzle for many hours as the front approaches.

Cold Front

 
A cold front is the leading edge of colder air. In front of it, you usually have warmer, more humid air. Behind the front lies much cooler or colder and drier air. The cause for cold fronts is colder air masses migrating southward from the polar regions. It is part of the world's natural energy circulation or cycle, this is how the earth "balances" out the warm and cold air masses around the earth.

High Pressure Centre

 
Indicates an area of high pressure. In a high pressure system, air will slowly descend and flow out in a clockwise direction at the ground. Normally a high will bring mainly sunny skies to an area.

 Low Pressure Centre

Indicates an area of low atmospheric pressure. In a low pressure system, air is flowing counterclockwise into the centre of the Low. The air will rise and cool often resulting in clouds and precipitation.

Trough

 

An elongated area of low pressure.

Jet Stream

 

The jet stream is like a current or river of air in the upper atmosphere, 7,000 to 13,000 meters up. It's created when cold and warm air masses come together. In the mid-latitudes of the Northern Hemisphere winds will tend to move from the west to the east. The jet stream, quite simply put, is the apex of these winds in the upper atmosphere. The minimum criterion for jet stream speed is 93 kilometers per hour. The location and orientation of the jet stream changes from day to day. Weather patterns are influenced by the position, strength and orientation of the jet stream.

Acknowledgement: This information is derived from the following website.
 

How to predict the Weather

 
 

Weather Forecasts:

 

Forecast  for Tomorrow for Regina, SK.


 

Weather Website 1,

 
, http://www.weatheroffice.gc.ca/city/pages/sk-32_metric_e.html
 
Monday Jan. 28 2011

·  Cloudy with 40 percent chance of flurries. High minus 7. Wind chill -11

  

Weather Website 2:

Monday Jan. 28  Cloudy with sunny breaks, chance of precipitation 30%
High Temp. -6 , wind 10 km/h, feels like -15, low temp. -12.

 

Weather Website 3:
Monday Jan. 28 2013
 P.O.P. 40%   High -7°    Low -19°



Chance of flurries

 


When we look at tomorrow’s forecast for Regina, SK. We observe that there is a slight difference between those forecasts. I think this is because of using different instruments and people reading   them.


 History Behind Predicting Weather

 

Man has always tried to predict weather as his survival has depended on weather and other natural conditions. The Babylonians in around 650 BC and Chinese Astronomers  in 300 BC used observation and calenders to predict weather.
 
Around 340 B.C., the Greek philosopher Aristotle wrote Meteorologica, he made some remarkably observations concerning the weather.  Throughout the centuries, people have attempted to make forecasts based on weather lore and personal observations. Galileo Galilei (1564-1642, Italian) invented an early thermometer in 1592. The following article sheds more light on this subject.


 

 

Thursday 24 January 2013

Wacky Weather

Heat, Flood or Icy Cold, Extreme Weather Rages Worldwide

http://www.nytimes.com/2013/01/11/science/earth/extreme-weather-grows-in-frequency-and-intensity-around-world.html?pagewanted=all&_r=0




 

Violence in the Sky




Posted by: Glen Boulier // January 16, 2013

Calgary, Alberta // Shot: August 18, 2011

Would finally build into a tornado...near Strathmore.

Wall Cloud: A wall cloud is an abrupt lowering of a rain-free cumulonimbus base into a low-hanging accessory cloud. A wall cloud is usually situated in the southwest portion of the storm. A rotating wall cloud usually develops before tornadoes or funnel clouds.

Funnel Cloud: A funnel cloud is a rotating cone-shaped column of air extending downward from the base of a thunderstorm, but not touching the ground. When it reaches the ground it is called a tornado.




Snow Flakes

Posted by: Dorothea Dawson // January 16, 2013

London, Ontario // Shot: January 14, 2013


Snowflakes on the hood of my car - I couldn't help but run inside and grab my camera and take some pictures - these are zoomed in of course! They are so beautiful! http://www.theweathernetwork.com/your_weather/web/imagepopup.php?imgname=http://rstorage.filemobile.com/storage/9534290/1085&title=Snowflakes&lang=en


Snowflakes are made of ice crystals. Each snowflake is six-sided and made of as many as 200 ice crystals. Snowflakes form in clouds where the temperature is below freezing. The ice crystals form around tiny bits of dirt that has been carried up into the atmosphere by the wind. As the snow crystals grow, they become heavier and fall toward the ground.
Snowflake

http://www.weatherwizkids.com/weather-winter-storms.htm

Tuesday 22 January 2013

Weather Related Events


 

Some of the weather related events are as follows:
 
Rain and flood

Air contains water vapors. When warm air moves up in the sky, water vapors in it gather to form clouds. If the clouds are big enough and have abundant water droplets, these droplets bang together and form bigger drops. When the drops get heavy, they fall because of gravity, and we have a rainfall.
 
If rain is heavy and it falls for days or there is a lot of snow and there is a meltdown, it can cause rivers to overflow causing a flood.



 
 
 
 
Thunderstorm
A thunderstorm is a storm with lightning and thunder along with the gusty winds, heavy rain and sometimes hail. A thunderstorm is formed when there is abundant moisture in the air which causes clouds and precipitation to form and when there is an uplift of the air. The uplift must be very strong to produce cumulonimbus cloud that reaches high above in the atmosphere.
 An unstable or active air circulation system comes into being because of a big temperature difference between the cold air of the high altitude and the warm air on the ground.

 
Hail 


Hail is created when small water droplets are caught in the updraft of a thunderstorm. These water droplets are lifted higher and higher into the sky until they freeze into ice. Once they become heavy, they will start to fall. If the smaller hailstones get caught in the updraft again, they will get more water on them and get lifted higher in the sky and get bigger. Once they get lifted again, they freeze and fall. This happens over and over again until the hailstone is too heavy and then falls to the ground.



 
 Tornadoes

A tornado is a very active rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes can cause tremendous destruction with wind speeds of up to 500 km/h. They can destroy large buildings, uproot trees and hurl vehicles A tornado’s damage path can exceed one kilometer wide to 30 kilometers long.
Most tornadoes form from thunderstorms.  In North America when warm, moist air from the Gulf of Mexico and cool, dry air from Canada meet, they create instability in the atmosphere. A change in wind direction and an increase in wind speed with increasing altitude create an invisible, horizontal spinning effect in the lower atmosphere. Rising air within the updraft tilts the rotating air from horizontal to vertical. An area of rotation, 4-10 kilometers wide, now extends through much of the storm. Most strong and destructive tornadoes form within this area of strong rotation.
 

 
Winter Storms

 

Winter storms get energized when two air masses of different temperatures and moisture levels clash. In North America winter storms usually form when an air mass of cold, dry, Canadian air moves southward and collides with a warm, moist air mass moving north from the Gulf of Mexico. The point where these two air masses meet is called a front. If cold air advances and pushes away the warm air, it forms a cold front. When warm air advances, it rides up over the denser, cold air mass to form a warm front. If neither air mass advances, it forms a stationary front.




Classification of some severe weather events according
 
to Environment Canada’s website:
 
 

Blizzard: A Blizzard warning is issued when winds of 40 km/hr or greater are expected to cause reduced visibility of 400 meters or less, due to blowing snow, or blowing snow in addition to falling snow, for at least 4 hours.

Blowing Snow: When blowing snow is caused by winds of at least 30 km/h, is expected to reduce visibility  to 800 meters or less for at least 3 hours then a blowing snow warning is issued.


Freezing Rain/ Drizzle: When rain or drizzle falls onto below zero ground
and freezes on contact forming a layer of ice causing slippery roads then a freezing rain warning is issued.

Severe Thunderstorm: A severe thunderstorm warning is issued when wind gusts of 90 km/h or greater, there is heavy rainfall along with hail of 2 centimeters in diameter or larger.