What does Observation Time Mean?
Much of the data at the Midwestern Regional Climate Center comes from National Weather Service cooperative observing stations where an observer records the temperature and precipitation at the same time every day. A common observation time is 7:00 a.m. Precipitation measured at that time would be the total amount for the 24-hour period from 7:00 a.m. the day before to 7:00 a.m. the day of the observation. However, not all stations have a 7:00 a.m. observation time. Some record from midnight to midnight, producing a true daily record, while others may record in the evening. Cooperative station data from the Midwestern Regional Climate Center will be stamped with an observation time of “AM”, “PM”, or “MID” to indicate the time of day when the observation was recorded. Whenever possible, the actual time of observation will be noted on the data.
