MCIP/WRF Precipitation

Dear all:
I ran several WRF cases and set the restart=’true’. After processing the data with MCIP, I encountered an issue when extracting the ‘RC’ variable. Specifically, there was a significant difference between the value at the last time step of the previous simulation and the value at the first time step of the next simulation (at the same time). The values may be same to be correct.


However, other variables such as ‘TEMP2’ and ‘PBL’ did not exhibit a similar issue; their values were consistent. I don’t know why? Thank you for your reply.


The problem is the way WRF writes out precipitation: it writes total accumulation since the start of the run, instead of an interpolatable, purely-MKS unit such as Kg/(M^2 Sec) [roughly equivalent to “vertical millimeters per second”]

That means you need to re-compute the precip (adjusting the subsequent run for the accumulation during the previous run) when you try to string more than one run together. Or else direc

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Your values for RC might be correct from MCIP. As mentioned by @cjcoats, WRF writes the precipitation components (RAINC and RAINNC) as running sums from the beginning of the simulation. The corresponding fields from MCIP (RC and RN) are computed into the increments for the output time interval (typically over an hour). If I interpreted your post correctly, rain occurred in the first hour after the restart, and that is what is reflected in the total that you showed.

If I did not interpret your post correctly, please write back and clarify what you are seeing.