Narrative:

Flight was to be from ZZZ to ZZZ2 with fuel stop in ZZZ1. Conditions to the west of ZZZ prior to departure appeared to be high dark clouds. Full briefing obtained from FSS indicated scattered light rain; occasional ts and high ceilings and light winds with conditions deteriorating over central and south state at XG00. Departed at XA00 and 1ST hour of flight showed light rain and 3 to 4000 ft AGL ceilings; calm winds. 2ND hour showed large areas ts circumvented with assistance from ZZZ3. Conditions deteriorated over the valley east of ZZZ1. Mountain obscuration and dropping ceilings developed around my position allowing no VFR escape. Contact with ZZZ3 was lost. FSS was unreachable. ZZZ4 approach was reached but was unable to vector me to improved conditions. Waited for improvement about 45 mins by flying large figure 8's over the valley. Several times I attempted to fly along the highway to the west but was met with very low ceilings over irregular terrain. Conditions did not improve. I made a precautionary landing on the remote and lightly traveled highway without difficulty; before fuel got too low. Was able to take off the following day in much clearer WX with the highway patrol blocking the road from each direction for about 5 mins.

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Original NASA ASRS Text

Title: A VFR C152 PLT ENCOUNTERED UNEXPECTEDLY POOR WX CONDITIONS ON A CROSS COUNTRY FLT AND LANDED ON A HWY.

Narrative: FLT WAS TO BE FROM ZZZ TO ZZZ2 WITH FUEL STOP IN ZZZ1. CONDITIONS TO THE W OF ZZZ PRIOR TO DEP APPEARED TO BE HIGH DARK CLOUDS. FULL BRIEFING OBTAINED FROM FSS INDICATED SCATTERED LIGHT RAIN; OCCASIONAL TS AND HIGH CEILINGS AND LIGHT WINDS WITH CONDITIONS DETERIORATING OVER CENTRAL AND S STATE AT XG00. DEPARTED AT XA00 AND 1ST HR OF FLT SHOWED LIGHT RAIN AND 3 TO 4000 FT AGL CEILINGS; CALM WINDS. 2ND HR SHOWED LARGE AREAS TS CIRCUMVENTED WITH ASSISTANCE FROM ZZZ3. CONDITIONS DETERIORATED OVER THE VALLEY E OF ZZZ1. MOUNTAIN OBSCURATION AND DROPPING CEILINGS DEVELOPED AROUND MY POSITION ALLOWING NO VFR ESCAPE. CONTACT WITH ZZZ3 WAS LOST. FSS WAS UNREACHABLE. ZZZ4 APCH WAS REACHED BUT WAS UNABLE TO VECTOR ME TO IMPROVED CONDITIONS. WAITED FOR IMPROVEMENT ABOUT 45 MINS BY FLYING LARGE FIGURE 8'S OVER THE VALLEY. SEVERAL TIMES I ATTEMPTED TO FLY ALONG THE HIGHWAY TO THE W BUT WAS MET WITH VERY LOW CEILINGS OVER IRREGULAR TERRAIN. CONDITIONS DID NOT IMPROVE. I MADE A PRECAUTIONARY LNDG ON THE REMOTE AND LIGHTLY TRAVELED HIGHWAY WITHOUT DIFFICULTY; BEFORE FUEL GOT TOO LOW. WAS ABLE TO TAKE OFF THE FOLLOWING DAY IN MUCH CLEARER WX WITH THE HWY PATROL BLOCKING THE ROAD FROM EACH DIRECTION FOR ABOUT 5 MINS.

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.