Narrative:

This was a part 121 scheduled flight from dtw to cak. WX conditions at both airports were IFR. An alternate airport was dtw. After pushback, but before taxi, I realized that, per the regulations, the second alternate was needed. Cle was added as a second alternate with an amendment made to the dispatch release. The forecast for cle was 800 ft overcast and temporarily 400 ft overcast. Landing was made in cak as scheduled. Upon review of the cle airport, I realized that a 500 ft ceiling in the forecast was necessary to make it a usable alternate airport.

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Original NASA ASRS Text

Title: SF34 CREW REALIZED THE NAMED WX ALTERNATE ARPT WAS BELOW ALTERNATE MINIMUMS. HE THEN NAMED A DIFFERENT ILLEGAL ALTERNATE.

Narrative: THIS WAS A PART 121 SCHEDULED FLT FROM DTW TO CAK. WX CONDITIONS AT BOTH ARPTS WERE IFR. AN ALTERNATE ARPT WAS DTW. AFTER PUSHBACK, BUT BEFORE TAXI, I REALIZED THAT, PER THE REGS, THE SECOND ALTERNATE WAS NEEDED. CLE WAS ADDED AS A SECOND ALTERNATE WITH AN AMENDMENT MADE TO THE DISPATCH RELEASE. THE FORECAST FOR CLE WAS 800 FT OVCST AND TEMPORARILY 400 FT OVCST. LNDG WAS MADE IN CAK AS SCHEDULED. UPON REVIEW OF THE CLE ARPT, I REALIZED THAT A 500 FT CEILING IN THE FORECAST WAS NECESSARY TO MAKE IT A USABLE ALTERNATE ARPT.

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.