I have a professional weather station here at my house in Denham Springs. I hit 98.4 degrees today. The airport got to 93. I generally run a few degrees warmer than the airport. Can my weather station be wrong? Also, I bought a $25 mercury thermometer from a local hardware store and it is placed under my patio and it was reading around "96ish". Please tell me if I should find a new spot for my temperature sensor.
In short, it would be MUCH easier to TALK this through because the details about instrument placement can be extensive!
#1: "Under" patio temperatures are NOT reliable/representative for regional purposes .. there could be 2 or 3 issues that come into play here.
#2: Instrument placement is AT LEAST as important as calibration. Most good weather systems provide quality sensors - where you PUT the sensors makes the MOST different.
#3: In truth, what is it you are trying to measure? If you really want to know the temperature on your patio, you're doing fine. But if you are trying to collect a regionally-representative number, then you need an open-air exposure as far away from buildings, trees, and concrete as possible. Most "small" backyards have trouble meeting these objectives.
#4: Although we use the airport as the "regional index" ... hmmm ... WHY do we use the airport? Who lives at the airport? Well, we often use airports becuase they generally have wide-open exposures.
However at some airports, the weather stations are too close to the runways, and concrete surfaces compromise the data quality.