C172 PLT REPORTS THAT AWOS REPORTED WINDS AT YOLO COUNTY ARPT; 2Q3; ARE OFTEN ERRONEOUS DUE TO THE LOCATION OF THE WIND SENSORS.

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THE AWOS WAS REPORTING; 'WINDS CALM.' THE WINDSOCK AT (ACROSS THE ROAD) THE START END OF RWY 34 SHOWED ABOUT 10 PLUS KTS. THE SKYDIVING OPERATION WAS ESTIMATING 15 KTS FOR THEIR JUMPERS. THE PLT OF BARON CONFIRMED THE AWOS 'CALM' REPORT. DURING FLT; THE GARMIN 1000 SHOWED WINDS GENERALLY 300 DEGS +/- AT 9-13 USUALLY. THE SAFETY ITEM INVOLVED IN THIS TYPE OF SITUATIONS IS 'OBJECT FIXATION.' SOMETIMES THIS FACTOR IS CALLED 'SINGLE INPUT DECISION MAKING' OR LACK OF 'TRIANGLES OF AGREEMENT.' IMAGINE A PLT ON FIRST SOLO XCOUNTRY TO 2Q3 AND THE AWOS REPORTING 'WINDS CALM.' THE AFD STATES RWY 34 IS THE CALM WIND RWY. WITH JUST THESE TWO FACTORS AS AN INPUT; CAN YOU IMAGINE A PLT LNDG RWY 34 WITH A TAILWIND OF SOME UNACCEPTABLE VALUE? I CAN. TO ADD TO THIS PROBLEM; THE ONLY COUNTY SUPPLIED ON ARPT WINDSOCK IS AT THE MIDFIELD TETRAHEDRON AND IS DIFFICULT TO SEE FROM THE START END OF RWY 34 OR RWY 16 -- THE PLT WHO KNOWS OF THE WINDSOCK ON THE FLYING HORSE RANCH OR THE DROP ZONE WINDSOCK HAS MORE INFO. OF COURSE; TREES AND PONDS NEARBY OFFER MORE INFO. SUGGESTIVE CORRECTIVE ACTION: PLACE A WINDSOCK (FRANGIBLE IF REQUIRED) AT THE START END OF RWYS 34 AND 16. THESE SMALLER WINDSOCKS ARE CHEAP AND PROVIDE A LAST FEW SECONDS OF DECISION MAKING INPUT TO A LNDG PLT. PLEASE NOTE ALSO THAT THE AIM SAY NOT TO TRUST TETRAHEDRONS.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THAT THE WINDSOCK AT SOUTH END OF THE RWY RARELY AGREES WITH THE AWOS REPORTED WIND. RPTR STATED THAT THE SENSORS FOR AWOS WIND REPORTS ARE LOCATED BETWEEN LARGE HANGARS; AND THE AWOS REPORTED WINDS ARE OFTEN INACCURATE; AFFECTED BY THOSE STRUCTURES.