Severe Weather in Bolivia

Tornadoes are able to form in regions where there is strong vertical wind shear. The wind speeds for a tornado range from 70 to 300 mph and the pressure can be as low as 900 mb.  They usually are formed in big thunder storms.  Some requirements that a tornado needs to form is cold outflow of air from downdrafts that does not undercut the updraft.  The strong vertical wind shear is what helps to create the horizontal spin, and then when the air is lifted, it begins to rotate.  Tornadoes become mesocyclones when the rotating air column exceeds 5 to 10 km diameter.  This just shows that the scale of the tornado is large enough to fit in the mesoscale criteria.

      In the Unites States tornadoes usually travel to the northeast.   The reason this is because the majority of tornadoes are formed east of the Rocky Mountains also the predominant winds in the Northern Hemisphere are Westerlies which drives the tornadoes east. Tornadoes do not happen in Bolivia because it is very mountainous in Bolivia.  There are 1,200 tornadoes in the US on average. < http://www.noaa.gov/features/protecting/tornados101.html  >  The average number of tornadoes in Bolivia is zero.  This website lists all the tornadoes to happen in South America and Bolivia was not on it.  <http://en.wikipedia.org/wiki/List_of_Southern_Hemisphere_tornadoes_and_tornado_outbreaks#South_America >

http://en.wikipedia.org/wiki/Tornado_climatology#mediaviewer/File:Pasillo_de_los_tornads_de_Am%C3%A9rica_del_Sur.jpg

The picture above shows the zone of tornadoes in South America.  The gray zone is high risk and the red zone is medium risk areas.  Bolivia is in the top right of this picture and is not affected by the tornadoes. 

Based on this graph it seems like tornadoes have been increasing over time.  This could be inaccurate because the first dates on this graph date all the way back to the 1950’s.  Back then they didn’t have the same advanced tools and technology to measure tornadoes as we do now, which could be one reason why it seems to be increasing over time.

The three main requirements for hurricane to form are usually over tropical waters where the winds are light and water temperature is warm typically over 80 degrees F, and the humidity is high extending up through the troposphere.  Bolivia does not meet these requirements.  The continent is hardly ever struck with hurricanes. The reason for this is that there are many fronts and air masses that push the hurricanes more north.  Also the conditions in the South Atlantic Ocean are too hostile for hurricanes to form.  There are three main hurricane formation regions, and the word for a hurricane differs from what region in the world we are referring to. In the Atlantic and east pacific it is called hurricane. In the Indian Ocean and near Australia it is called cyclones, and off the coast of China and Indonesia it is called typhoons.

In the US hurricanes usually form in the Caribbean Sea and then travel to the northwest until they hit a large land mass.  Also the Westerlies push the storms back to the east which causes them to travel to northern Europe.  The few that make it onto US landmasses typically break up because of the friction with land and those that turn early and go back out to the Atlantic Ocean and break down because of cooler ocean temperatures.  There are no hurricanes that happen in Bolivia.  There are about 5 to 6 hurricanes that hit yearly. <http://www.aoml.noaa.gov/hrd/tcfaq/E19.html>  I couldn't find a website that said that there were no hurricanes, but this picture below shows that there has been no hurricanes that hit anywhere neat Bolivia.

http://www.bing.com/images/search?q=Hurricane%20History%20Map%20south%20america&qs=n&form=QBIR&pq=hurricane%20history%20map%20south%20america&sc=0-28&sp=-1&sk=#view=detail&id=D8DFF8AEEAA5EB091AD9F282DD8F5C977ABB4353&selectedIndex=2

Daily Weather in Bolivia

       The capital city of Bolivia, is Sucre. My three day forecast will cover Thursday October 30th, Friday October 31st, and Saturday November 1st.  The forecast for Thursday, October 30th is the high being 75 degrees Fahrenheit, and the low at 53 degrees Fahrenheit.  The chance of precipitation percentage is 50 percent.  For Friday, October 31st, the forecast showed the high being 77 degrees Fahrenheit, and the lows being 52 degrees Fahrenheit.  The percent for precipitation is 20 percent.  Lastly, on Saturday, November 1st, the forecast showed the highs being at 72 degrees Fahrenheit and the lows at 51 degrees Fahrenheit.  There is a 50 percent chance of it raining on this day.  The pressure over these three days stayed the same.  The average wind speed was 11 miles per hour.  The wind speed decreased over the three day period.

Current Satellite Image of Sucre, Bolivia

       There are many visible clouds.  There are some, but only a few low and warm clouds.  Most of the clouds are high and cold clouds.  This means that they are far away from the surface.  When looking at the radar map, you can see light precipitation in some areas Sucre.  There is no heavy precipitation anywhere.   There are lakes around Sucre.  There is no green coloration, which means that there is no forests or parks.   The surface is all gray and rough which represents  mountains and cities. 

     This map shows a zoomed in perspective of my country.  The isobar pressures on this map range from 1008 mb all the way to 1021 mb.  There are no low pressures shown on this zoomed in map.  There is a big low pressure right around the middle, and it is equal to 1008 mb.

     This is a more broad view, which gives a wider look of my country and its surroundings.  On this map there are isobars ranging from 1012 mb to 1032mb.  There are many high and low pressures all around this map, three of each.  There are a few fronts on this map as well.  There are both cold fronts, and warm fronts.  Most are located southeast of my country, but some are also located southwest of Bolivia.