If you've checked the current temperature map recently, you might have noticed that Hearne gets considerably hotter than many of the other local airports during the day. There are two possible explanations: either Hearne is in a unique micro-climate that warms more rapidly than the rest of Central Texas, or the temperature sensor in use at Hearne is broken. The general consensus in the Doppler 10 Forecast Center is that the thermometer is out to lunch.

This begs two questions:

1) What's wrong with the sensor?
Unfortunately, there's no way to know for sure until the broken sensor is taken out of commission and examined. We can make some guesses based on the data the temperature sensor is outputting. We know the temperature seems to skyrocket during daylight hours, then returns to near-normal at night. We also know that the problem is most pronounced in summer, and less noticeable in winter. That leads me to believe that the temperature sensor is not being properly shielded from the sun. When a thermometer is exposed to direct sunlight, the temperature reads much higher than it otherwise should. Another possibility is that the temperature sensor has been located over concrete, asphalt, or another location otherwise unsuitable for placing a thermometer.

2) Why doesn't somebody fix it?
That's a good question! The sensor is part of an instrumentation system known as an AWOS, or Automated Weather Observing System. It's located at Hearne's Municipal Airport, a little ways west of the city of Hearne. Although the National Weather Service uses the data collected at the site, it usually isn't the National Weather Service's job to maintain the equipment or to replace it if it's faulty. The FAA certifies the equipment being used at the site, but isn't in charge of installing it or overseeing its operation. TxDOT may have funded the installation of the weather system, but I'm not sure if they're responsible for maintaining it. That just leaves the City of Hearne, which owns the airport and may have to foot the bill for any repairs to the system. The bottom line is that I'm unsure who's in charge of fixing the problem, and until someone does, Hearne's temperature will continue to read a little on the warm side.