CPC unified (gauge-based) precipitation
X axis: whole world in 720 0.50° steps, first point at 0.25° E, last point at 359.75° E
Y axis: regular grid with 360 0.50° steps, first point at 89.75° S, last point at 89.75° N

1-daily data available from 01Jan1979 to 31Dec2019 ( 15006 times)
Variable prcp (precipitation) in mm/dy
Full metadata.

Get grid points, average area or generate subset

Mask:	no mask mask1.txt mask5.txt   add a mask to the list
Latitude:	°N - °N
Longitude:	°E - °E
Boundaries:	halfway grid points interpolated
Make:	average max min set of grid points subset of the field
Demand at least:	% valid points in this region
Units:	convert to mm/day leave in mm/dy

Create a field with lower time resolution

New time scale:	annual (Jul-Jun) annual (Jan-Dec) biannual seasonal monthly 10-daily 5-daily
New variable:	mean sd sum sum above sum below number min time of min max time of max first time last time of precipitation
Threshold:	no cut less than greater than mm/dy percentile normal 1971-2000
Minimum:	% valid data
First apply:	-day running mean
Missing data:	ignore, climatology, trend, persistence.

Create a field with lower spatial resolution

Average over blocks of longitude and latitude grid cells

Construct a statistical forecast model from this field

Please consider downloading this field from the authoritative site.
If you really want to get it here, CPC daily precipitation is available as a netcdf file (size 3934.91 MB).