Narrative:

We approached tvf, field elevation 1116 ft, from the northwest in VMC. Clouds were few at 2100 ft MSL. An earlier PIREP reported cloud layer scattered at 2500 ft MSL. ASOS current field conditions were not checked until entering the downwind leg for runway 31 at tvf. The cloud layer above the pattern was broken at 2100 ft. Flight visibility at the field was 5 NM. ASOS reported a ceiling of 500 ft (1600 ft MSL) broken, IMC, at the time we entered the pattern and the ZMP class east controled airspace. While listening to the ASOS, an unidented person informed us the field was under IMC. We made 1 landing and departed the field on the upwind leg of runway 31. After departing the airport we re-entered the VMC (described earlier) to the northwest of the field. We proceeded VFR in VMC back to ZZZ1. Although it was unclr, we had made a VFR landing in controled airspace at tvf while the field was under a reported IMC ceiling. Contributing factors: PIC's over reliance on a PIREP for cloud ht, and PIC's failure to check the ASOS prior to entering the airport vicinity.

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Original NASA ASRS Text

Title: A VFR PA28-161 WITH AN INSTRUCTOR AND STUDENT MADE A LNDG AND TKOF AT AN ARPT THAT WAS BELOW VFR MINIMUMS. AN UNIDENTED PERSON INFORMED THAT THE ARPT WAS IMC.

Narrative: WE APCHED TVF, FIELD ELEVATION 1116 FT, FROM THE NW IN VMC. CLOUDS WERE FEW AT 2100 FT MSL. AN EARLIER PIREP RPTED CLOUD LAYER SCATTERED AT 2500 FT MSL. ASOS CURRENT FIELD CONDITIONS WERE NOT CHKED UNTIL ENTERING THE DOWNWIND LEG FOR RWY 31 AT TVF. THE CLOUD LAYER ABOVE THE PATTERN WAS BROKEN AT 2100 FT. FLT VISIBILITY AT THE FIELD WAS 5 NM. ASOS RPTED A CEILING OF 500 FT (1600 FT MSL) BROKEN, IMC, AT THE TIME WE ENTERED THE PATTERN AND THE ZMP CLASS E CTLED AIRSPACE. WHILE LISTENING TO THE ASOS, AN UNIDENTED PERSON INFORMED US THE FIELD WAS UNDER IMC. WE MADE 1 LNDG AND DEPARTED THE FIELD ON THE UPWIND LEG OF RWY 31. AFTER DEPARTING THE ARPT WE RE-ENTERED THE VMC (DESCRIBED EARLIER) TO THE NW OF THE FIELD. WE PROCEEDED VFR IN VMC BACK TO ZZZ1. ALTHOUGH IT WAS UNCLR, WE HAD MADE A VFR LNDG IN CTLED AIRSPACE AT TVF WHILE THE FIELD WAS UNDER A RPTED IMC CEILING. CONTRIBUTING FACTORS: PIC'S OVER RELIANCE ON A PIREP FOR CLOUD HT, AND PIC'S FAILURE TO CHK THE ASOS PRIOR TO ENTERING THE ARPT VICINITY.

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.