A hot air balloon was caught above fast forming fog.

Attributes
ACN	283302
Time
Date	199409
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : 2s6
State Reference	OR
Altitude	agl bound lower : 0 agl bound upper : 500
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tower : dus
Operator	general aviation : personal
Make Model Name	Balloon
Operating Under FAR Part	Part 91
Flight Phase	descent : approach landing : go around landing other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial
Experience	flight time last 90 days : 70 flight time total : 700 flight time type : 700
ASRS Report	283302
Events
Anomaly	inflight encounter : weather non adherence : far other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

Flight launched with foggy patches in local area, but clear overload and 1 mi plus visibility. Flight went fine until the final landing was missed and a climb to 2000 ft for steering allowed fog to form under the balloon in an area that had been clear a few mins earlier. I descended through dense fog from 500 ft AGL to visual contact with ground (about 100 ft) landing was made immediately. I would insure this doesn't happen again by keeping a suitable landing size always available, especially when climbing to altitude.

Original NASA ASRS Text

Title: A HOT AIR BALLOON WAS CAUGHT ABOVE FAST FORMING FOG.

Narrative: FLT LAUNCHED WITH FOGGY PATCHES IN LCL AREA, BUT CLR OVERLOAD AND 1 MI PLUS VISIBILITY. FLT WENT FINE UNTIL THE FINAL LNDG WAS MISSED AND A CLB TO 2000 FT FOR STEERING ALLOWED FOG TO FORM UNDER THE BALLOON IN AN AREA THAT HAD BEEN CLR A FEW MINS EARLIER. I DSNDED THROUGH DENSE FOG FROM 500 FT AGL TO VISUAL CONTACT WITH GND (ABOUT 100 FT) LNDG WAS MADE IMMEDIATELY. I WOULD INSURE THIS DOESN'T HAPPEN AGAIN BY KEEPING A SUITABLE LNDG SIZE ALWAYS AVAILABLE, ESPECIALLY WHEN CLBING TO ALT.

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.