X axis: whole world in 720 0.50° steps, first point at 179.75° W, last point at 179.75° E
Y axis: regular grid with 160 0.50° steps, first point at 39.75° S, last point at 39.75° N

Monthly data available from Dec1997 to Apr2013 ( 185 months)
Variable prcp (SURFACERAIN) in mm/hrmm/hr

Get grid points, average area or generate subset

Latitude:	°N - °N
Longitude:	°E - °E
Boundaries:	halfway grid points interpolated
Make:	average set of grid points subset of the field
Demand at least:	% valid points in this region
Units:	convert to mm/day leave in mm/hrmm/hr

Create a field with lower time resolution

New time scale:	annual (Jul-Jun) annual (Jan-Dec) seasonal monthly 10-daily 5-daily 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/hrmm/hr percentile normal 1971-2000
Minimum:	% valid data

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, TRMM precipitation is available as a netcdf file (size 81.3092 MB).