Narrative:

I was instructing in a VFR aircraft at an uncontrolled airport and called the aircraft while just took off to ask for ceiling. Aircraft reported 1000'. I took off and determined the ceiling was 1000' MSL, a true ceiling of 300' AGL. I had to declare an emergency because of low ceiling and rapidly declining visibility.

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Original NASA ASRS Text

Title: GA SMA TOOK OFF ON A TRAINING FLT IN WX BELOW VFR MINIMUMS. NON TWR ARPT WITH PLT USING PLT REPORTED WX FOR CEILING.

Narrative: I WAS INSTRUCTING IN A VFR ACFT AT AN UNCONTROLLED ARPT AND CALLED THE ACFT WHILE JUST TOOK OFF TO ASK FOR CEILING. ACFT RPTED 1000'. I TOOK OFF AND DETERMINED THE CEILING WAS 1000' MSL, A TRUE CEILING OF 300' AGL. I HAD TO DECLARE AN EMER BECAUSE OF LOW CEILING AND RAPIDLY DECLINING VISIBILITY.

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.