Daily Observations Lead to Yearly Records
Weather records are witnessed nearly everyday in the United States. New records replace or tie old records thanks to daily weather observations that are tracked in thousands of communities across the country. These daily weather observations are logged for decades—some even more than a century. Over time, these observations are averaged together to give us an idea of the climate of a particular area. Climatology is primarily concerned with the collective average of weather conditions whereas meteorology is the science dealing with actual weather conditions, the atmosphere and its phenomena. For example, a meteorologist might tell you that a chance of rain is in the forecast for May 25, 2018. A climatologist will tell you that May 25th averages 0.35 inches of rain every year.
Speaking of rain, one city in Montana did not receive their average (also called “normal”) amount of yearly precipitation. Glasgow, in northeastern Montana, had their driest year on record in 2017. Daily weather observations in that city date back to 1893. Climatology tells us that Glasgow should typically receive 11.66 inches of precipitation per year. In 2017, however, only 6.64 inches of precipitation fell….the lowest amount on record. Interestingly enough, Glasgow had their 2nd-wettest year on record in 2016 with 20.84 inches of rain. Conditions can vary greatly from year to year, that’s why it’s important to rely on climatology for overall trends and patterns.
Another city setting a yearly record in 2017 was Tampa, Florida. It was the hottest year on record in that city. The average temperature (the average of the high and low temperature for all 365 days) was 76.3 degrees. This beat the previous hottest year on record (2015) by 0.1 degrees. Daily weather observations date back to 1939 in Tampa. The “normal” yearly temperature in this Gulf Coast city is 73.4 degrees. The city of Melbourne, Florida also observed their hottest year on record during 2017 with an average temperature of 75.6 degrees.
As you might guess, there are several different time frames for tracking weather and climate records. The three examples above are yearly records, which can only be calculated after December 31st each year. There are also seasonal, monthly, and daily records. In the eastern two-thirds of the United States, dozens of daily record cold temperatures were observed during the last few days of 2017. This trend will continue for several more days and may very well have an impact on 2018’s yearly climate statistics.