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  2. IEM Computed Hourly Precipitation Totals

The IEM attempts to take the METAR reports of precipitation and then provide just the hourly precipitation totals. These totals are not for the true hour (00 to 59 after), but for the hour between the standard METAR reporting time, typically :53 or :54 after. The timestamps displayed are in Central Daylight/Standard Time and for the hour the precipitation fell. So a value for 5 PM would roughly represent the period between 4:53 and 5:53 PM. Backend documentation exists for those that wish to script against the backend service.

Data prior to 2010 only contains the non-zero values, whereas all hours are accounted for after 2010. This may be fixed in upcoming work on the database. For now, assume zeros for any data prior to 2010 for missing hours.

Select network to download from:

1) Select Station(s):

2) Select period:

YearMonthDay
Start:
End:

3) Metadata


4) Timezone of Observation Times:

The following options are available for how the observation time is presented.

Download Fields

station
Common identifier for the station.
network
Network identifier for the station.
valid
Hour on which the precip fell.
precip_in
Hourly Precipitation [inch]. A value of 0.0001 denotes a Trace.
lat
Station Latitude (deg N), when selected.
lon
Station Longitude (deg E), when selected.
st
Station State Indentifier, when selected.