Narrative:

While returning from a long cross country flight at night in good VFR (clear below 12000 ft, 10 mi visibility), I noticed in the landing lights a small amount of wispy cloud. I never lost easy sight of ground while in this layer, nor did I lose sight of sky above. I also had 3 mi of horizontal visibility throughout. I am instrument rated and current, though I was not in an IFR equipped aircraft nor on an IFR flight plan. I put on the carburetor heat and began watching the struts for airframe icing as I reported to the approach controller, who was providing me with flight following, that I had entered a wispy cloud and due to reduced visibility, I was 'out of 3000 ft for 3500 ft.' finding some visible moisture still present slightly below the aircraft, I reported I was 'out of 3500 ft for 4000 ft' and climbed to that altitude. I began to look for an area not covered by this layer and quickly found one 2 mi to my right. I told the controller that I was going to 'make a 90 degree right turn, to an area of clear sky. The controller asked if I wanted to continue on to my destination as it was 'only 10 mi away.' I advised that I did not feel comfortable doing this and that I was going to fly to the area of clear sky and descend to 2000 ft to put myself well below the layer and continue home. This was approved and this is what I did, returning home in a few mins without further trouble. 1/2 hour before departing for this flight, I obtained a standard VFR WX briefing and WX was forecast to be clear below 12000 ft and visibility greater than 10 mi throughout the night. As I was still a few mins from my destination, I had not yet checked my home airport's ATIS and as I had encountered no unforecast conditions en route, I had no reason to expect this thin cloud layer at my altitude. Despite the clarity of the night, it was impossible to see the cloud layer, as it blended completely into a benign line of haze that had been slightly above the horizon for the entire flight, so my entry into this layer was very surprising, though uneventful and quickly remedied.

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Original NASA ASRS Text

Title: PLT OF C152 ENCOUNTERED CLOUD DECK WHILE ON NIGHT VFR FLT. EXITED CONDITION AND RETURNED TO DEP ARPT.

Narrative: WHILE RETURNING FROM A LONG XCOUNTRY FLT AT NIGHT IN GOOD VFR (CLR BELOW 12000 FT, 10 MI VISIBILITY), I NOTICED IN THE LNDG LIGHTS A SMALL AMOUNT OF WISPY CLOUD. I NEVER LOST EASY SIGHT OF GND WHILE IN THIS LAYER, NOR DID I LOSE SIGHT OF SKY ABOVE. I ALSO HAD 3 MI OF HORIZ VISIBILITY THROUGHOUT. I AM INST RATED AND CURRENT, THOUGH I WAS NOT IN AN IFR EQUIPPED ACFT NOR ON AN IFR FLT PLAN. I PUT ON THE CARB HEAT AND BEGAN WATCHING THE STRUTS FOR AIRFRAME ICING AS I RPTED TO THE APCH CTLR, WHO WAS PROVIDING ME WITH FLT FOLLOWING, THAT I HAD ENTERED A WISPY CLOUD AND DUE TO REDUCED VISIBILITY, I WAS 'OUT OF 3000 FT FOR 3500 FT.' FINDING SOME VISIBLE MOISTURE STILL PRESENT SLIGHTLY BELOW THE ACFT, I RPTED I WAS 'OUT OF 3500 FT FOR 4000 FT' AND CLBED TO THAT ALT. I BEGAN TO LOOK FOR AN AREA NOT COVERED BY THIS LAYER AND QUICKLY FOUND ONE 2 MI TO MY R. I TOLD THE CTLR THAT I WAS GOING TO 'MAKE A 90 DEG R TURN, TO AN AREA OF CLR SKY. THE CTLR ASKED IF I WANTED TO CONTINUE ON TO MY DEST AS IT WAS 'ONLY 10 MI AWAY.' I ADVISED THAT I DID NOT FEEL COMFORTABLE DOING THIS AND THAT I WAS GOING TO FLY TO THE AREA OF CLR SKY AND DSND TO 2000 FT TO PUT MYSELF WELL BELOW THE LAYER AND CONTINUE HOME. THIS WAS APPROVED AND THIS IS WHAT I DID, RETURNING HOME IN A FEW MINS WITHOUT FURTHER TROUBLE. 1/2 HR BEFORE DEPARTING FOR THIS FLT, I OBTAINED A STANDARD VFR WX BRIEFING AND WX WAS FORECAST TO BE CLR BELOW 12000 FT AND VISIBILITY GREATER THAN 10 MI THROUGHOUT THE NIGHT. AS I WAS STILL A FEW MINS FROM MY DEST, I HAD NOT YET CHKED MY HOME ARPT'S ATIS AND AS I HAD ENCOUNTERED NO UNFORECAST CONDITIONS ENRTE, I HAD NO REASON TO EXPECT THIS THIN CLOUD LAYER AT MY ALT. DESPITE THE CLARITY OF THE NIGHT, IT WAS IMPOSSIBLE TO SEE THE CLOUD LAYER, AS IT BLENDED COMPLETELY INTO A BENIGN LINE OF HAZE THAT HAD BEEN SLIGHTLY ABOVE THE HORIZON FOR THE ENTIRE FLT, SO MY ENTRY INTO THIS LAYER WAS VERY SURPRISING, THOUGH UNEVENTFUL AND QUICKLY REMEDIED.

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.