Page 1 of 1

LBC for cycled runs

PostPosted: Thu Mar 29, 2018 3:07 pm
by Minghua Zheng
Hi WRFDA users,

I am doing a 6-hr cycled run using GFS operational forecast as initial and lateral boundary conditions.
One question is: how to compute boundary conditions after the first run?
Let's assume my initial run starts from 0000 UTC Jan 1st 2018;
IC at 0000 UTC: GFS operational analysis (run1)
LBC at 0000 UTC: GFS 6-h forecast

2nd run: at 0600 UTC Jan 1st
Background: 6-h forecast from run1;
IC: updated BACKGROUND after WRFDA;
LBC: ????updated LBC for next cycle??

For the 2nd run, I can use boundary condition from initial downscaled GFS forecast, and update it using WRFDA utility.
However, this LBC will be quite inaccurate as the GFS forecast lead time will increase with more cycled runs.
Also, GFS will only have two weeks's forecast.
What should I do after 2weeks? What is the correct way to set up LBC for different cycles?

Any comments/discussions will be super helpful to me.