During a family outing the other day, I spotted something that reckons back to the How not to measure temperature series at WUWT. A weather observation station is installed at the Philosopher’s Walk at Trinity College of the University of Toronto, which appears to be the one code named CXTO in the international databases, which has apparently been in operation for almost two hundred years.
What got my attention was the wind. There was a 20+gust knot northwest wind most of the day. But the anemometer installed at the station was a wee indecisive. It pointed in every direction induced by the random turbulence from the adjacent tall buildings. In this picture, they point in opposite directions (compare the flag and the anemometer propeller nose).
To their credit, the proprietors of CXTO do not broadcast the wind measurements along with the regular METAR, so the nonsense data from the useless sensor does not travel widely. OTOH, the temperature readings are published, and being a few dozen feet from a highly-radiative high-thermal-mass stone wall almost certainly distorts the readings. Likewise, one might suspect that the sun irradiance sensors won’t work quite right with tall buildings and trees casting shadows. At least weather measurements aren’t used for anything too important.