Narrative:

I obtained a WX briefing through duat. VFR was forecast all day. I listened to ATIS. It reported 10000 broken visibility 10 mi. After we preflted the airplane, conditions had changed to 5000 broken visibility 2 1/2 mi. As we were going to be conducting touch-and-goes in the traffic pattern, I asked for a special VFR clearance, which I received. In my judgement 2 1/2 mi and 5000 broken would be sufficient. After we took off, I could see clouds ahead so we turned crosswind. I could see clouds beneath me so I turned downwind to try to return for landing (I could see the approach end of the runway we had just departed). I turned base but I could not see the end of the runway as there was a cloud bank between us. I stayed on top and tried another runway but it too became obscured by the time I was on final. I circled and climbed until I was well above the clouds and tower assisted me to a nearby airport (uncontrolled) where I was able to make a VFR landing. The cause for this situation was the unforecast low ceiling which were drastically different to what had been reported by ATIS. There is a WX reporting station at the airport and I did not expect such a discrepancy.

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Original NASA ASRS Text

Title: INSTRUCTOR PLT TRIES SVFR FOR PATTERN WORK. WX MOVES IN SO FAST FLT ASSIST NEEDED TO NEARBY ARPT.

Narrative: I OBTAINED A WX BRIEFING THROUGH DUAT. VFR WAS FORECAST ALL DAY. I LISTENED TO ATIS. IT RPTED 10000 BROKEN VISIBILITY 10 MI. AFTER WE PREFLTED THE AIRPLANE, CONDITIONS HAD CHANGED TO 5000 BROKEN VISIBILITY 2 1/2 MI. AS WE WERE GOING TO BE CONDUCTING TOUCH-AND-GOES IN THE TFC PATTERN, I ASKED FOR A SPECIAL VFR CLRNC, WHICH I RECEIVED. IN MY JUDGEMENT 2 1/2 MI AND 5000 BROKEN WOULD BE SUFFICIENT. AFTER WE TOOK OFF, I COULD SEE CLOUDS AHEAD SO WE TURNED XWIND. I COULD SEE CLOUDS BENEATH ME SO I TURNED DOWNWIND TO TRY TO RETURN FOR LNDG (I COULD SEE THE APCH END OF THE RWY WE HAD JUST DEPARTED). I TURNED BASE BUT I COULD NOT SEE THE END OF THE RWY AS THERE WAS A CLOUD BANK BTWN US. I STAYED ON TOP AND TRIED ANOTHER RWY BUT IT TOO BECAME OBSCURED BY THE TIME I WAS ON FINAL. I CIRCLED AND CLBED UNTIL I WAS WELL ABOVE THE CLOUDS AND TWR ASSISTED ME TO A NEARBY ARPT (UNCTLED) WHERE I WAS ABLE TO MAKE A VFR LNDG. THE CAUSE FOR THIS SITUATION WAS THE UNFORECAST LOW CEILING WHICH WERE DRASTICALLY DIFFERENT TO WHAT HAD BEEN RPTED BY ATIS. THERE IS A WX RPTING STATION AT THE ARPT AND I DID NOT EXPECT SUCH A DISCREPANCY.

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.