Narrative:

Received flight following along route from prineville, or (S39), towards private strip near hugo VOR, co (hgo). At burley, identification, received WX update from boise radio of VFR not recommended along route. Diverted at that time to casper, wy, which was reporting VFR well beyond my ETA. Approximately 40 mi west of cpr, received ATIS for airport reported 10 mi visibility with a 6000 ft ceiling. At 25 mi west I contacted cpr approach for radar assistance and confirmation of ATIS report. WX appeared marginal, however, cpr approach assured me it was patching to the west and continued to be VFR. I proceeded, requesting continued radar assistance. 18 mi west of airport, I was entering marginal to IMC conditions at 7700 ft MSL indicated. At 5 mi from airport, I became VFR and continued to landing. At no time was I in an emergency situation nor was the aircraft in an unusual attitude. 2 souls were on board. Approximately 30 mins after landing cpr became IFR with blowing snow and low ceilings. Possible solution: expand ATIS to summarize surrounding area (10-25 mi) conditions for en route traffic.

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Original NASA ASRS Text

Title: PVT PLT IN C210 GETS INTO LOW CLOUDS PRIOR TO REACHING CPR, WY. HE WAS DIVERTING DUE TO WX ALONG HIS PLANNED RTE TO HUGO, CO. COMPLAINS OF ATIS NOT GIVING ACTUAL WX CONDITIONS 25 MI FROM ARPTS.

Narrative: RECEIVED FLT FOLLOWING ALONG RTE FROM PRINEVILLE, OR (S39), TOWARDS PVT STRIP NEAR HUGO VOR, CO (HGO). AT BURLEY, ID, RECEIVED WX UPDATE FROM BOISE RADIO OF VFR NOT RECOMMENDED ALONG RTE. DIVERTED AT THAT TIME TO CASPER, WY, WHICH WAS RPTING VFR WELL BEYOND MY ETA. APPROX 40 MI W OF CPR, RECEIVED ATIS FOR ARPT RPTED 10 MI VISIBILITY WITH A 6000 FT CEILING. AT 25 MI W I CONTACTED CPR APCH FOR RADAR ASSISTANCE AND CONFIRMATION OF ATIS RPT. WX APPEARED MARGINAL, HOWEVER, CPR APCH ASSURED ME IT WAS PATCHING TO THE W AND CONTINUED TO BE VFR. I PROCEEDED, REQUESTING CONTINUED RADAR ASSISTANCE. 18 MI W OF ARPT, I WAS ENTERING MARGINAL TO IMC CONDITIONS AT 7700 FT MSL INDICATED. AT 5 MI FROM ARPT, I BECAME VFR AND CONTINUED TO LNDG. AT NO TIME WAS I IN AN EMER SIT NOR WAS THE ACFT IN AN UNUSUAL ATTITUDE. 2 SOULS WERE ON BOARD. APPROX 30 MINS AFTER LNDG CPR BECAME IFR WITH BLOWING SNOW AND LOW CEILINGS. POSSIBLE SOLUTION: EXPAND ATIS TO SUMMARIZE SURROUNDING AREA (10-25 MI) CONDITIONS FOR ENRTE TFC.

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.