What is a Mesonet?
A mesonet is a dense network of automated surface observing stations that provides temperature, precipitation, dew point, wind speed, wind direction, etc. data. These sensors are strategically positioned across a region to provide the highest quality of weather data. For instance, some sites are located in valleys while other sites are on ridge tops. The closely spaced observing sites help to measure small scale weather phenomena that larger scale forecast models and observing networks cannot pick up. The data is critical when forecasting severe weather onset, ridge and valley temperature splits, frontal passages, and determining winter precipitation type. Mesonet data is also archived, which provides a large database of extremely important climatological data. Check out the Kentucky Mesonet website.
Why are these data valuable?
A dense network of accurate weather data is invaluable to local climatologists, meteorologists, utility companies, insurance companies, the general public, etc. For instance, these data are critical to NWS meteorologists during severe weather operations because of the ability to measure wind speeds and gusts. These measurements help meteorologists determine how strong a particular thunderstorm might be (Example 1 below). Also, the ability to measure precipitation really helps when monitoring how well the radar is estimating rainfall (Example 2 below). Imagine how helpful the data are when temperatures are hovering around freezing and meteorologists are trying to determine whether rain, freezing rain, sleet, or snow will fall. Climatologists use these data to look at past weather (e.g., "How much rain fell last July compared to this July?" or "What was the coldest day in January last year?"). These are just a few of the hundreds of uses that the mesonet data provide.
The images above from May 2, 2010 depict a strong radar signature passing over the Kentucky Mesonet site located 7 miles west of Campbellsville in Taylor County. The Kentucky Mesonet data displayed a maximum wind of 35 mph, although stronger winds may have been nearby. This information helps meteorologists make critical warning decisions.
The image above shows radar estimated precipitation totals from the May 1-2, 2010 very heavy rain event. The image below shows actual rainfall measurements from the same time frame using several different Kentucky Mesonet sites. This data helps meteorologists determine how well the radar is estimating precipitation, and can be critical in flood/flash flood decisions. To truly display how helpful this information is, look at the Clinton County observation of 8.22". This amount is almost double what the radar was estimating due to its distance from the radar site!
What is the Kentucky Mesonet?
The Kentucky Mesonet is Kentucky's very own network of surface observing stations operated and maintained by Western Kentucky University. There are 65 sites across the Commonwealth, each providing accurate and reliable "ground truth" information that serve hundreds of purposes for many different users.
Supporting and Promoting the Kentucky Mesonet
Pictured below: Meteorologist in Charge of the NWS Louisville, KY office gives a presentation about the benefits of the Kentucky Mesonet, along with Dr. Stu Foster from Western Kentucky University. The talk was in front of the American Association of State Climatologists (AASC) at the Hyatt Regency arch in downtown St. Louis, MO on July 11, 2013.