Narrative:

We were on a local training flight at addison airport, tx. ATIS information at addison reported 7 mi visibility, few clouds at 2000 ft, broken clouds at FL200. On takeoff during climb out, visibility to deteriorate rapidly to below VFR required minimum. Because of our low altitude (800 ft AGL) I decided to climb up to VFR on top. At that time I informed my student that we were canceling our flight and heading back under IFR. I called regional approach, informed them of our situation, and requested a return to addison under IFR flight plan. After our return, ATIS information was still reporting 3 mi visibility and now 3000 ft, few clouds, which we obviously knew was wrong. The addison ATIS has always been just a bit off in the past, but this time it really caught us off guard.

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Original NASA ASRS Text

Title: PIPER ARCHER TRAINING FLT FLEW INTO IFR CONDITIONS DURING DEP CLB DUE TO DETERIORATING WX LESS THAN RPTED BY ADIZ.

Narrative: WE WERE ON A LCL TRAINING FLT AT ADDISON ARPT, TX. ATIS INFO AT ADDISON RPTED 7 MI VISIBILITY, FEW CLOUDS AT 2000 FT, BROKEN CLOUDS AT FL200. ON TKOF DURING CLBOUT, VISIBILITY TO DETERIORATE RAPIDLY TO BELOW VFR REQUIRED MINIMUM. BECAUSE OF OUR LOW ALT (800 FT AGL) I DECIDED TO CLB UP TO VFR ON TOP. AT THAT TIME I INFORMED MY STUDENT THAT WE WERE CANCELING OUR FLT AND HEADING BACK UNDER IFR. I CALLED REGIONAL APCH, INFORMED THEM OF OUR SIT, AND REQUESTED A RETURN TO ADDISON UNDER IFR FLT PLAN. AFTER OUR RETURN, ATIS INFO WAS STILL RPTING 3 MI VISIBILITY AND NOW 3000 FT, FEW CLOUDS, WHICH WE OBVIOUSLY KNEW WAS WRONG. THE ADDISON ATIS HAS ALWAYS BEEN JUST A BIT OFF IN THE PAST, BUT THIS TIME IT REALLY CAUGHT US OFF GUARD.

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.