Narrative:

I left pwc for fcm to pick up a passenger. I checked the WX in fcm before I left to monitor the track of a rain storm. I was told that flying southwest would be worse WX than flying west and a little north. This would keep me out of the rain, for the most part. I revised my planned route to allow for a little deviation north around the worst WX. No thunderstorms reported, just rain, fog and some low ceilings. 100 NM from fcm the WX seemed to be closing in. I diverted north more as originally advised, but the sky got darker and it started raining. There were 2 or more layers of clouds and as I passed 1g2 a lower layer came in view, potentially creating a situation where we were trapped between layers. Against my passenger's pleas to continue, I turned around about 5 mi past 1g2 and landed there without incident.

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Original NASA ASRS Text

Title: C172 PLT DIVERTS TO AN ALTERNATE ARPT DUE TO WX.

Narrative: I LEFT PWC FOR FCM TO PICK UP A PAX. I CHKED THE WX IN FCM BEFORE I LEFT TO MONITOR THE TRACK OF A RAIN STORM. I WAS TOLD THAT FLYING SW WOULD BE WORSE WX THAN FLYING W AND A LITTLE N. THIS WOULD KEEP ME OUT OF THE RAIN, FOR THE MOST PART. I REVISED MY PLANNED RTE TO ALLOW FOR A LITTLE DEV N AROUND THE WORST WX. NO TSTMS RPTED, JUST RAIN, FOG AND SOME LOW CEILINGS. 100 NM FROM FCM THE WX SEEMED TO BE CLOSING IN. I DIVERTED N MORE AS ORIGINALLY ADVISED, BUT THE SKY GOT DARKER AND IT STARTED RAINING. THERE WERE 2 OR MORE LAYERS OF CLOUDS AND AS I PASSED 1G2 A LOWER LAYER CAME IN VIEW, POTENTIALLY CREATING A SIT WHERE WE WERE TRAPPED BTWN LAYERS. AGAINST MY PAX'S PLEAS TO CONTINUE, I TURNED AROUND ABOUT 5 MI PAST 1G2 AND LANDED THERE WITHOUT INCIDENT.

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.