Narrative:

Our flight was assigned 8000 ft MSL by departure on a vector to pie. First officer (PF) was hand flying aircraft and exceeded assigned altitude by 400 ft. Happened while captain was attempting to contact departure for deviations around WX. Numerous thunderstorms in area may have caused 'heads out of cockpit' to avoid turbulent WX. Immediately returned to 8000 ft uneventfully. Exceeded altitude no more than 30 seconds duration.

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Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT -- ACR CLBS ABOVE ITS ASSIGNED ALT WHILE CIRCUMNAVING TSTMS.

Narrative: OUR FLT WAS ASSIGNED 8000 FT MSL BY DEP ON A VECTOR TO PIE. FO (PF) WAS HAND FLYING ACFT AND EXCEEDED ASSIGNED ALT BY 400 FT. HAPPENED WHILE CAPT WAS ATTEMPTING TO CONTACT DEP FOR DEVS AROUND WX. NUMEROUS TSTMS IN AREA MAY HAVE CAUSED 'HEADS OUT OF COCKPIT' TO AVOID TURBULENT WX. IMMEDIATELY RETURNED TO 8000 FT UNEVENTFULLY. EXCEEDED ALT NO MORE THAN 30 SECONDS DURATION.

Data retrieved from NASA's ASRS site as of July 2007 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.