Narrative:

I was on a VFR flight in my C180. Checked WX and looked at the latest radar plot before leaving. Although marginal it seemed reasonable. Ceilings of 1500 ft and visibility 7-8 mi. I monitored the ZZZ; ZZZ1 and ZZZ2 AWOS xmissions when I was able to receive them. All were reporting ceiling of 3500 ft and visibility of 10 mi. The WX between my position and ZZZ2 degraded and I diverted to ZZZ3. I was approximately 15 mi from ZZZ when the next AWOS report from there reported 3/4 mi visibility and light snow. At this point I turned around and headed back to ZZZ4; behind me. This also went to less than 1 mi and light snow. I was down to approximately 900 ft AGL at this point. I then decided to call ZZZ approach for a WX update. Same visibility was reported. I elected to continue into the class D airspace after declaring an emergency. I had the ground in sight but as it was becoming dark I thought a landing at the ZZZ4 airport was preferable to landing on a road/field. That was a viable option as I know the area intimately and had a GPS moving map; the ILS and VOR tuned and idented; etc. I was unable to climb to the MEA's for that area as moderate icing was reported in the clouds above 10000 ft. I believe the MEA's on that section of the en route area are 9000-10000 ft. Looking back on this event I realize the WX was not good enough to attempt the flight. If I were in the same situation again I would call approach and ask for a contact approach. The event ended well considering how I had boxed myself into a corner. I landed in snow with the runway in sight at approximately 1 mi. In the future I will not fly in such marginal conditions.

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Original NASA ASRS Text

Title: TRAPPED BY CLOSING IN WX AND LOWERING FREEZING LEVELS; C180 PLT DECLARES EMER TO LAND SAFELY.

Narrative: I WAS ON A VFR FLT IN MY C180. CHKED WX AND LOOKED AT THE LATEST RADAR PLOT BEFORE LEAVING. ALTHOUGH MARGINAL IT SEEMED REASONABLE. CEILINGS OF 1500 FT AND VISIBILITY 7-8 MI. I MONITORED THE ZZZ; ZZZ1 AND ZZZ2 AWOS XMISSIONS WHEN I WAS ABLE TO RECEIVE THEM. ALL WERE RPTING CEILING OF 3500 FT AND VISIBILITY OF 10 MI. THE WX BTWN MY POS AND ZZZ2 DEGRADED AND I DIVERTED TO ZZZ3. I WAS APPROX 15 MI FROM ZZZ WHEN THE NEXT AWOS RPT FROM THERE RPTED 3/4 MI VISIBILITY AND LIGHT SNOW. AT THIS POINT I TURNED AROUND AND HEADED BACK TO ZZZ4; BEHIND ME. THIS ALSO WENT TO LESS THAN 1 MI AND LIGHT SNOW. I WAS DOWN TO APPROX 900 FT AGL AT THIS POINT. I THEN DECIDED TO CALL ZZZ APCH FOR A WX UPDATE. SAME VISIBILITY WAS RPTED. I ELECTED TO CONTINUE INTO THE CLASS D AIRSPACE AFTER DECLARING AN EMER. I HAD THE GND IN SIGHT BUT AS IT WAS BECOMING DARK I THOUGHT A LNDG AT THE ZZZ4 ARPT WAS PREFERABLE TO LNDG ON A ROAD/FIELD. THAT WAS A VIABLE OPTION AS I KNOW THE AREA INTIMATELY AND HAD A GPS MOVING MAP; THE ILS AND VOR TUNED AND IDENTED; ETC. I WAS UNABLE TO CLB TO THE MEA'S FOR THAT AREA AS MODERATE ICING WAS RPTED IN THE CLOUDS ABOVE 10000 FT. I BELIEVE THE MEA'S ON THAT SECTION OF THE ENRTE AREA ARE 9000-10000 FT. LOOKING BACK ON THIS EVENT I REALIZE THE WX WAS NOT GOOD ENOUGH TO ATTEMPT THE FLT. IF I WERE IN THE SAME SITUATION AGAIN I WOULD CALL APCH AND ASK FOR A CONTACT APCH. THE EVENT ENDED WELL CONSIDERING HOW I HAD BOXED MYSELF INTO A CORNER. I LANDED IN SNOW WITH THE RWY IN SIGHT AT APPROX 1 MI. IN THE FUTURE I WILL NOT FLY IN SUCH MARGINAL CONDITIONS.

Data retrieved from NASA's ASRS site as of January 2009 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.