Narrative:

Deviating for thunderstorms. Over focus on WX -- missed altitude clearance of 12000 ft. ATC called to check altitude at 144200 ft and advised of crossing traffic at 13000 ft. Skywatch advised but did not alert. Crossing traffic observed visually -- no factor; no deviations necessary. Contributing factor was altitude alert (airsport pro) was in shop for repair.

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Original NASA ASRS Text

Title: A C210 PLT CLRED TO 12000 FT FAILED TO LEVEL AND CLBED TO 14200 FT. WX DIVERSIONS AND INOP ALT ALERT WERE FACTORS.

Narrative: DEVIATING FOR TSTMS. OVER FOCUS ON WX -- MISSED ALT CLRNC OF 12000 FT. ATC CALLED TO CHK ALT AT 144200 FT AND ADVISED OF XING TFC AT 13000 FT. SKYWATCH ADVISED BUT DID NOT ALERT. XING TFC OBSERVED VISUALLY -- NO FACTOR; NO DEVS NECESSARY. CONTRIBUTING FACTOR WAS ALT ALERT (AIRSPORT PRO) WAS IN SHOP FOR REPAIR.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.