Figure 3.4-2a Bluefield Individual Sensor Element Comparisons
Bluefield, WV
The average comparability of the individual sensors for Bluefield was 91%. The comparability for visibility, temperature and wind direction was less than expected. This assessment was subject to multiple uncontrolled variables such as observer estimates and interpolations of visibility, sky cover, etc. IFR and MVFR conditions occurred at Bluefield during 51 hours out of a total of about 386 hours. Analysis showed that visibility comparability was less than expected during these conditions. For the range of zero to two miles, the ASOS agreed with the human observer within the specified limits, 54% of the time; in the range above two miles through four miles the agreement was 50%; while at five miles the ASOS agreed with the human observer 59% of the time.