Narrative:

Transited fullerton in VFR conditions eastbound, following 91 freeway, after leaving fullerton traffic area. Maintained radio contact with fullerton while proceeding toward canyon. Visibility looked ok so I proceeded into moderate rain. Visibility dropped to 2-2.5 mi for 1-2 mins. Could not climb due to fog and clouds at higher altitudes. Upon reaching midpoint in canyon, visibility improved to 4 mi, ceiling ragged. Rain stopped at midpoint just prior to reaching prado dam. Eastbound visibility improved to 5-15 mi. Lesson: when I started into the canyon visibility was not too bad. It got worse as I was transiting. Next time I'll go after the WX has cleared to full VFR not just marginal VFR.

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Original NASA ASRS Text

Title: VFR IN IMC CONDITIONS AS SMA PLT PRESSES THE ENRTE WX.

Narrative: TRANSITED FULLERTON IN VFR CONDITIONS EBOUND, FOLLOWING 91 FREEWAY, AFTER LEAVING FULLERTON TFC AREA. MAINTAINED RADIO CONTACT WITH FULLERTON WHILE PROCEEDING TOWARD CANYON. VISIBILITY LOOKED OK SO I PROCEEDED INTO MODERATE RAIN. VISIBILITY DROPPED TO 2-2.5 MI FOR 1-2 MINS. COULD NOT CLB DUE TO FOG AND CLOUDS AT HIGHER ALTS. UPON REACHING MIDPOINT IN CANYON, VISIBILITY IMPROVED TO 4 MI, CEILING RAGGED. RAIN STOPPED AT MIDPOINT JUST PRIOR TO REACHING PRADO DAM. EBOUND VISIBILITY IMPROVED TO 5-15 MI. LESSON: WHEN I STARTED INTO THE CANYON VISIBILITY WAS NOT TOO BAD. IT GOT WORSE AS I WAS TRANSITING. NEXT TIME I'LL GO AFTER THE WX HAS CLRED TO FULL VFR NOT JUST MARGINAL VFR.

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.