Update to GFS Precipitation

Dave Casson, modified 10 Months ago.

Update to GFS Precipitation

Keen Forecaster Posts: 4 Join Date: 6/19/19 Recent Posts

GFS forecast precipitation, as accessed by OpenDAP, now is accumulative over the entire forecast. Previously it was accumulation per timestep.

The GFS variable ( apcpsfc , surface total precipitation [kg/m^2]) exists with the same identifier, but now is in this different structure.


The fix is to add         <externUnit parameterId="PC.nwp" unit="mm" cumulativeSum="true"/> to the precipitation data import. Please note that this fix will work for 2018.02. For 2017.02 a new patch is required.


This change was intentional but not very advertised. A notice can be found here effective June 12:

II) New total precipitation and convective precipitation, with continuous accumulation, will be added to the output. Examples of the new variables: APCP:surface:0-10 day acc fcst ACPCP:surface:0-10 day acc fcst.  It is confusing that the same variable query from the NAM forecast returns the accumulation per timestep.




Martijn Kwant, modified 9 Months ago.

RE: Update to GFS Precipitation

Keen Forecaster Posts: 8 Join Date: 6/13/19 Recent Posts
Thanks for the update Dave.