Narrative:

We were descending for approach. My initial operator experience (IOE) captain upgrade student picked up ATIS. Visibility 10 SM and a few clouds at 2;100 ft.; which was what had been forecast. I briefed a visual approach to runway 30 backed up with the RNAV GPS Z runway 30. (ILS 30 OTS). As we checked in with the final approach controller we were told [a new] ATIS was current. [First officer] picked up [new ATIS] and briefed me that the ceiling had gone down to 500 feet broken. I quickly briefed the full RNAV approach and [we] were given a vector to the south. We were eventually given a descent to 3;000 feet and cleared for the approach. As we approached; the snowflake began to descend from the top of the pfd and it was at this point I lost situational awareness and was thinking I would be cleared to descend to 1;600 feet. On the snowflake. I began a descent and didn't realize we were not yet at [the descent point] until descending thru 2;000 feet. I then began a climb back to 3;000 ft. And shortly thereafter were informed by the approach controller that he had an altitude alert and told us to confirm [we would cross a waypoint] at 3;000 feet. We acknowledged we were returning to 3;000 feet. And continued the approach.we ultimately failed to break out at minimums and executed the missed approach. We took vectors back around and on our second attempt; broke out at minimums; and landed.I can only say that fatigue may have been a factor in doing something so stupid. It was the final leg of a 4-leg day. We had been delayed on maintenance the night before and were reduced to a 10-hour layover with a late show the following day. I only got about 6 hours sleep and had been doing IOE with a different student until [this] flight. Additionally; on the preceding leg; we got a wind shear warning accompanied by moderate to severe turbulence shortly after takeoff; which may have contributed to still being somewhat distracted.

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Original NASA ASRS Text

Title: CRJ-900 flight crew reported ATC issued a low altitude alert when they descended below charted altitude on the approach.

Narrative: We were descending for approach. My Initial Operator Experience (IOE) Captain upgrade student picked up ATIS. Visibility 10 SM and a few clouds at 2;100 ft.; which was what had been forecast. I briefed a visual approach to Runway 30 backed up with the RNAV GPS Z Runway 30. (ILS 30 OTS). As we checked in with the final Approach Controller we were told [a new] ATIS was current. [First Officer] picked up [new ATIS] and briefed me that the ceiling had gone down to 500 feet BKN. I quickly briefed the full RNAV approach and [we] were given a vector to the south. We were eventually given a descent to 3;000 feet and cleared for the approach. As we approached; the snowflake began to descend from the top of the PFD and it was at this point I lost situational awareness and was thinking I would be cleared to descend to 1;600 feet. on the snowflake. I began a descent and didn't realize we were not yet at [the descent point] until descending thru 2;000 feet. I then began a climb back to 3;000 ft. and shortly thereafter were informed by the Approach Controller that he had an altitude alert and told us to confirm [we would cross a waypoint] at 3;000 feet. We acknowledged we were returning to 3;000 feet. and continued the approach.We ultimately failed to break out at minimums and executed the missed approach. We took vectors back around and on our second attempt; broke out at minimums; and landed.I can only say that fatigue may have been a factor in doing something so stupid. It was the final leg of a 4-leg day. We had been delayed on maintenance the night before and were reduced to a 10-hour layover with a late show the following day. I only got about 6 hours sleep and had been doing IOE with a different student until [this] flight. Additionally; on the preceding leg; we got a wind shear warning accompanied by moderate to severe turbulence shortly after takeoff; which may have contributed to still being somewhat distracted.

Data retrieved from NASA's ASRS site 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.