The B-91 Form is the monthly summary form used by NWS Coop Observers to record their observations. Begin a new form on the first of every month by filling in the heading and bottom of the form completely.
Most entries are self-evident.
Enter your name, station index number, and supervising office on the bottom of the form. This sample form shows how entries should be made at stations taking river, precipitation, and temperature observations. Take your observations at the same hour each day, if at all possible. Prior approval is needed to change the scheduled time of observation. The times of observation should be entered in the third line of the heading and at the top of the river stage column.