Narrative:

Prior to departing sac for las, I secured a very extensive WX briefing in the auxiliary FSS at sac. My initial and primary concern was about the potential turbulence en route over the mountains. As it turned out, that phase of the flight was silky smooth. Las was reporting 2000 E50 overcast with 35, light rain showers. This forecast to improve prior to my arrival to 3000 scattered, ceiling 6000 broken, occasional ceiling 3000 broken light rainshowers, and after xaz 6000 scattered, ceiling 1000 broken occasional ceiling 6000 broken, and after xcz VFR. En route I had encountered some scattered clouds and at times breaks below my altitude of 11500. As I approached beatty I observed some clouds ahead at my altitude and requested WX from center. It was reported to be 2000 scattered, 3000 broken, 5000 occasional. Since it had not improved as expected, I still anticipated primarily broken to scattered conditions until reaching lower altitudes below the freezing level so I requested and obtained an IFR clearance at 12000. Soon after entering the clouds I encountered some light mixed icing so immediately requested 130 expecting to climb above the clouds. At that time, I intended to see if further flight would be possible since I would need to get back down to 12000 right away. When I did break out of the clouds I requested an immediate 180. As soon as I was clear of the clouds I cancelled IFR and proceeded to a lower altitude to get rid of the ice and proceeded VFR to reno and landed there. The lesson I learned from this experience is do not let forecast WX influence my opinion of current conditions. I learned later as I secured a number of WX updates, that the las WX was up and down all day, but never improved as expected until much later. We remained in reno overnight, (glad to be on the ground) and enjoyed a beautiful cavu smooth flight to las the following morning.

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Original NASA ASRS Text

Title: SMA ENCOUNTERS WX, FILES IFR, DIVERTS TO LAND.

Narrative: PRIOR TO DEPARTING SAC FOR LAS, I SECURED A VERY EXTENSIVE WX BRIEFING IN THE AUX FSS AT SAC. MY INITIAL AND PRIMARY CONCERN WAS ABOUT THE POTENTIAL TURB ENRTE OVER THE MOUNTAINS. AS IT TURNED OUT, THAT PHASE OF THE FLT WAS SILKY SMOOTH. LAS WAS RPTING 2000 E50 OVCST WITH 35, LIGHT RAIN SHOWERS. THIS FORECAST TO IMPROVE PRIOR TO MY ARR TO 3000 SCATTERED, CEILING 6000 BROKEN, OCCASIONAL CEILING 3000 BROKEN LIGHT RAINSHOWERS, AND AFTER XAZ 6000 SCATTERED, CEILING 1000 BROKEN OCCASIONAL CEILING 6000 BROKEN, AND AFTER XCZ VFR. ENRTE I HAD ENCOUNTERED SOME SCATTERED CLOUDS AND AT TIMES BREAKS BELOW MY ALT OF 11500. AS I APCHED BEATTY I OBSERVED SOME CLOUDS AHEAD AT MY ALT AND REQUESTED WX FROM CTR. IT WAS RPTED TO BE 2000 SCATTERED, 3000 BROKEN, 5000 OCCASIONAL. SINCE IT HAD NOT IMPROVED AS EXPECTED, I STILL ANTICIPATED PRIMARILY BROKEN TO SCATTERED CONDITIONS UNTIL REACHING LOWER ALTS BELOW THE FREEZING LEVEL SO I REQUESTED AND OBTAINED AN IFR CLRNC AT 12000. SOON AFTER ENTERING THE CLOUDS I ENCOUNTERED SOME LIGHT MIXED ICING SO IMMEDIATELY REQUESTED 130 EXPECTING TO CLB ABOVE THE CLOUDS. AT THAT TIME, I INTENDED TO SEE IF FURTHER FLT WOULD BE POSSIBLE SINCE I WOULD NEED TO GET BACK DOWN TO 12000 RIGHT AWAY. WHEN I DID BREAK OUT OF THE CLOUDS I REQUESTED AN IMMEDIATE 180. AS SOON AS I WAS CLR OF THE CLOUDS I CANCELLED IFR AND PROCEEDED TO A LOWER ALT TO GET RID OF THE ICE AND PROCEEDED VFR TO RENO AND LANDED THERE. THE LESSON I LEARNED FROM THIS EXPERIENCE IS DO NOT LET FORECAST WX INFLUENCE MY OPINION OF CURRENT CONDITIONS. I LEARNED LATER AS I SECURED A NUMBER OF WX UPDATES, THAT THE LAS WX WAS UP AND DOWN ALL DAY, BUT NEVER IMPROVED AS EXPECTED UNTIL MUCH LATER. WE REMAINED IN RENO OVERNIGHT, (GLAD TO BE ON THE GND) AND ENJOYED A BEAUTIFUL CAVU SMOOTH FLT TO LAS THE FOLLOWING MORNING.

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.