St. Louis, Missouri, Essay Example

Situational

On a winter day in St. Louis, Missouri, a fluctuating pattern of rain, sleet and snow occurs. The day began with snow in the early morning before the warmth of the afternoon turned the precipitation to rain. As the sun began its descent and the warmth dissipated, the rain turned to icy sleet again in the evening. This weather pattern is not uncommon in the Midwestern United States. The following essay will explain the causes of precipitation fluctuations as seen on this hypothetical day.

Meteorological Explanation

The rise of the sun causes a natural change in the atmospheric temperature. Snow requires temperatures of 32°F or lower, which is the freezing temperature of water. In the morning the temperature was likely in the twenties, causing snow to accumulate. Once the sun rose, a natural heat overcame the atmospheric chill and the precipitation became rain in the higher temperature. As the sun set, the temperature lowered to one hovering around 32 degrees Fahrenheit. This caused the rain to mix with sleet and the cold air of the evening formed ice along the bridges.

Weather fronts are transitions between air masses of cold and warm air. The frontal zone is the slice of cold air that leads into an area of warmer air. In this situational, this is a cold front. If the warm air moves to an area that is primarily cold, then the front is considered a warm one.

References

“Weather Fronts”. (2005). Retrieved on November 2, 2010 from MesoNet.org: http://okfirst.mesonet.org/train/meteorology/Fronts.html

“Occluded Fronts”. (2010). Retrieved on November 2, 2010 from UIUC.edu: http://ww2010.atmos.uiuc.edu/%28Gh%29/guides/mtr/fcst/sfc/ofrnt.rxml

“Weather Fronts”. (2010). Retrieved on November 2, 2010 from BBC.co.uk: http://www.bbc.co.uk/weather/features/understanding/fronts.shtml