Narrative:

Nexrad and radar showed clear skies at FL250. Encountered WX and extreme turbulence. Declared emergency and deviated left immediately. Approach cleared to VFR conditions. Landed at ZZZ to review WX situation. Trust only your eyes at FL200 and IMC.

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Original NASA ASRS Text

Title: BEECHCRAFT DUKE BE60 PLT ENCOUNTERS SEVERE TURB WHILE AT CRUISE; DECLARES AN EMER AND LANDS.

Narrative: NEXRAD AND RADAR SHOWED CLR SKIES AT FL250. ENCOUNTERED WX AND EXTREME TURB. DECLARED EMER AND DEVIATED L IMMEDIATELY. APCH CLRED TO VFR CONDITIONS. LANDED AT ZZZ TO REVIEW WX SITUATION. TRUST ONLY YOUR EYES AT FL200 AND IMC.

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.