As seasons change, months end, and years come to a close, we often hear about how that particular period’s weather compares to normal. You may wonder, what is “normal”?
“Normal” refers to the 30-year average of a particular meteorolgical variable, such as temperature or precipitation, in a specific location. This average is a statistical number that gives us an idea of what to expect as well as a point of reference for historical comparisons. These figures are useful to scientists who study climate change and to industries, such as power and construction, who utilize the data for planning purposes.
The “normals” are calculated every decade for the previous 30-year period by the National Climatic Data Center (NCDC), a division of the National Oceanic and Atmospheric Administration. They have a mandate from Congress dating back to 1890 to “… to establish and record the climatic conditions of the United States.” In addition, the United States is a member of the U.N.’s World Meteorological Organization (WMO). As a member nation, we follow their guidelines for computing 30-year averages.
The NCDC recently released their new “normals” based on the years 1981 to 2010.
Many aspects of the economy are dependent on the weather. The agricultural sector is especially vulnerable to extreme conditions. Crops need just the right amount of water. Either too much or too little is bad news.
This summer and early fall we had excessive rain and serious flooding in the North East. This extreme weather has affected many crops with pumpkins being a high profile seasonal example.
Depending on their location, some crops washed away in floods or rotted from a moisture loving fungus. As a result, there will be less pumpkins in the patches this year in certain areas. So, go early for a good selection. It should also be noted that according the laws of supply and demand, we can most likely expect to pay a little more for our Halloween pumpkins this year.
It was both warmer and wetter than normal in New York City this September. We received 9.39 inches of rain in Central Park. That is over twice our average amount of precipitation for the month. We also measured in at 2 degrees Fahrenheit above average.
The first few days of October have continued the wet weather pattern. As the month progresses, however, we should look forward to crisper air and changing leaves.