Narrative:

Departing jyo approximately XA00, skies were clear less than 12000 ft. I climbed to 10500 ft and headed wsw. I wanted almost direct southwest for touchdown at pdk, but I knew the WX would be bad and I probably wouldn't make it. However, it appeared I could go west over the mountains, get past the front, then go south or southeast toward pdk as far as possible depending on the ceilings. As I went west, the cumulus started to build under me (tops approximately 8000 ft, higher in isolated spots). However, with lots of holes, I didn't worry too much (and figured I was getting towards the end anyway). However, as I passed over the mountains, the clouds got thicker, rather than thinner. I kept altering course further nnw, where I could see blue skies. However, I ultimately reached the point where I only had 1/2 hour of fuel, and no end in sight of the clouds. I used the GPS/nearest feature and managed to find 1 airport with 1) relatively flat surrounding landscape and 2) 1400 ft ceilings (highest reported in a 50 mi radius). I used the autoplt to descend to 1400 ft (while circling with the heading bug) and did a visual approach at 2AO. (Where I sat for another day waiting for an IFR-rated pilot to get me home.) although all WX predictions (several sources) I consulted indicated a definite western edge to the front, it obviously built in a way not predicted by the models. I should have put down (after doing a 180 degree turn) as soon as the cloud cover below me got even close to marginal and not trusted predictions.

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Original NASA ASRS Text

Title: LOW TIME GA PLT ENCOUNTERS ENRTE WX.

Narrative: DEPARTING JYO APPROX XA00, SKIES WERE CLR LESS THAN 12000 FT. I CLBED TO 10500 FT AND HEADED WSW. I WANTED ALMOST DIRECT SW FOR TOUCHDOWN AT PDK, BUT I KNEW THE WX WOULD BE BAD AND I PROBABLY WOULDN'T MAKE IT. HOWEVER, IT APPEARED I COULD GO W OVER THE MOUNTAINS, GET PAST THE FRONT, THEN GO S OR SE TOWARD PDK AS FAR AS POSSIBLE DEPENDING ON THE CEILINGS. AS I WENT W, THE CUMULUS STARTED TO BUILD UNDER ME (TOPS APPROX 8000 FT, HIGHER IN ISOLATED SPOTS). HOWEVER, WITH LOTS OF HOLES, I DIDN'T WORRY TOO MUCH (AND FIGURED I WAS GETTING TOWARDS THE END ANYWAY). HOWEVER, AS I PASSED OVER THE MOUNTAINS, THE CLOUDS GOT THICKER, RATHER THAN THINNER. I KEPT ALTERING COURSE FURTHER NNW, WHERE I COULD SEE BLUE SKIES. HOWEVER, I ULTIMATELY REACHED THE POINT WHERE I ONLY HAD 1/2 HR OF FUEL, AND NO END IN SIGHT OF THE CLOUDS. I USED THE GPS/NEAREST FEATURE AND MANAGED TO FIND 1 ARPT WITH 1) RELATIVELY FLAT SURROUNDING LANDSCAPE AND 2) 1400 FT CEILINGS (HIGHEST RPTED IN A 50 MI RADIUS). I USED THE AUTOPLT TO DSND TO 1400 FT (WHILE CIRCLING WITH THE HEADING BUG) AND DID A VISUAL APCH AT 2AO. (WHERE I SAT FOR ANOTHER DAY WAITING FOR AN IFR-RATED PLT TO GET ME HOME.) ALTHOUGH ALL WX PREDICTIONS (SEVERAL SOURCES) I CONSULTED INDICATED A DEFINITE WESTERN EDGE TO THE FRONT, IT OBVIOUSLY BUILT IN A WAY NOT PREDICTED BY THE MODELS. I SHOULD HAVE PUT DOWN (AFTER DOING A 180 DEG TURN) AS SOON AS THE CLOUD COVER BELOW ME GOT EVEN CLOSE TO MARGINAL AND NOT TRUSTED PREDICTIONS.

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.