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First frame spike

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New member
Hi WRF people,

So, I am running wrf. Everything runs fine and I don't get any errors.
My problem is that the first frame of my run is all crazy high (for one variable). Then the following two are low.
I am not sure why this happens, any ideas on what could cause this?

All the best
I added screen shots for the JAN 2000 case on the WRF website.
As you can see, frame 1 I get a huge spike, then frames 2 and 3 go down (4 and 5 are also down, I didn't add those).

Any ideas what can cause this?


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At the first several hours of simulation, we expect to see large variation of pressure due to possible inconsistency in the initial field, especially noises caused by imbalances between wind and mass fields.
But in the WRF tutorial case that this is based on (JAN 2000), there isn't one. The P field doesn't have a high variation.
Why do we expect it but it's not in the test case?
The noise may occur if large inconsistency exists between initial wind and mass fields. In some cases with better initial field, the noise may not be that significant.