Data Analysis

A few diagrams from our first exercise:

 The map above shows the positions and directions of movement of air masses that effect North America. When there are troughs in the jet stream, we're likely getting air from the continental polar or continental arctic air masses. When there is a ridge in the jetstream in our area, we are getting air from the martime tropical to the southwest or continental air masses over central America.

 The image above is one I put together depicting the surface conditions for  February 7. The arrows depict wind, the longer the arrow, the higher the wind speed. From this, you can see that there was a low moving through at the time.

The current surface map above describes the fronts - what kind of air is in front and behind each front.



Diagram from exercise 3:

As the title of the diagram states, this map shows surface wind speeds and direction for March 5, 2013. One can pick up weather patterns by looking at wind data alone. With this data there seems to be a low pressure system over the western parts of the Dakotas and stronger winds coming from the southwest running through the middle of the US. A little can be told about the jetstream as well. There may be a low pressure system down in the northwestern part of Texas. Many of the low pressure systems that have come through this winter have generally started in the west-central US (around Colorado, Nebraska). It also looks like there could be a trough in the jet stream over Montana and North Dakota which has also been common this winter with those troughs traveling to the east toward the east coast.





Microclimate diagrams:

Diagrams from exercise 6:

 This graph above shows the average monthly temperature for the month of March beginning in 1895 to the
present. Looking at the general trend, the graph seems to vary the normal amount hovering around the average 41 F. Starting in 1960 through present day, the average temperature begins to rise.  This year’s average, 40.76 F, is nearly 10 F lower than the average for March, 2012 at 50.4 F. Even though the temperature for March, 2013 is much lower than 2012, it is closer to the 1901-2000 average of 41.63 F, off by 0.87 F.

Like the contiguous U.S. temperature graph, this temperature graph, above, for the month of March in Wisconsin shows a trend that does not change much from 1895 to around 1950. Starting in 1950, an increasing trend in the average temperature begins to emerge. The average temperature for Wisconsin from 1901 to 2000 is 28.9 F, 12.73 F lower than the Contiguous U.S. average. The average for 2013 is 23.8 F, 5.1 F below the 1901-2000 average. The average for 2012 is 45.4 F, 16.5 F higher than the 1901-2000 average. It makes sense that Wisconsin’s average temperatures in March would be lower than those of the Contiguous U.S. due to its geographic location.

This graph shows the average precipitation For the contiguous U.S. for March from 1895 to present. Overall, there does not seem to be a noticeable trend from 1895 to present. The average precipitation for March is 2.4 inches. This year’s precipitation for March is 1.68 inches, 0.72 inches below the average. This year’s preicp. is also less than last year’s, which was 2.7 inches.

Here are the averages for the precipitation during March for Wisconsin. Again, there does not seem to be any trends through the last century in regards to the years becoming wetter or drier. Both this year and last year were wetter than average. 2012 only saw 0.4 inches more of precipitation than this year, which received 1.95 inches. What should be noted in the above four graphs is most of the large peaks above average in precipitation or temperature are followed by large peaks below average.  

This graph to the left shows the average temperatures of Madison, WI and Milwaukee, WI for each month of the year.  As typical of the Midwest, temperatures peak in July and the coldest months are January and February. The coldest month for Madison is January with a temperature of 16 F, while the warmest month, July, has a temperature of 71 F. Milwaukee’s coldest month is also January with a temperature of 18.9 F, while the warmest month is July with a temperature of 70.9 F.

The following graphs are climographs of the larger cities of Wisconsin and of Minneapolis, MN. They show the monthly average temperatures and precipitations in relation to each other. These climographs show that the warmer months are also the most precipitous, as the cooler months receive the least amount of precipitation.

In regards to the above climographs, all of these cities are located in the upper Midwest and should therefore have similar weather. Topography and geographic location could play a role in temperatures and precipitation. Eau Claire and Minneapolis receive a lot of the same weather, although parts of Eau Claire are in a valley, which can affect the weather. Other cities such as Milwaukee, which is located next to Lake Michigan may receive more precipitation due to lake effect or lake enhancement.

However, the data collected for all of the cities is not all from the same source. Also, some years may be missing for some cities while for other cities those years are available, even though the data is from the same source. This would have an effect on the averages with some cities having used more years to calculate the average temp. and precip. than other cities.

The following graphs represent the daily averages of temperature, precipitation, and wind directions for the months January through April.

A general trend that can be seen throughout January, February, and March are that the greatest precipitation occurred during the warmer times of those months. The average monthly temperatures for these months were still below 32 F, so this makes sense. Slightly warmer temperatures are associated with low pressure systems coming through. This trend does not occur in April, when the average temperature seems to be over 32 F. April also has the greatest amount of total precipitation, 29.3 inches, twice as much precipitation than January, February, and March combined.

When comparing the daily pressure diagram for April with the climograph of Eau Claire, April seems to have exceeded the monthly average 10 times over. The precipitation for January through March was also above average. January and February were warmer than average, where March and April were cooler than average.

Overall, it appears that this winter, and so far this spring, was more precipitous than average. Winter was warmer than average and spring is looking to be cooler than average. So, all of the mid-latitude cyclones that contributed to the precipitation we received this winter/spring is not normal, but well above average. 

From exercise 7: