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I am trying to run a real simulation with LES in debug mode, after having run ndown and v_interp, in order to ensure there are o problems before running LES. However I get the following error messages after 8 time steps:

Program received signal SIGFPE: Floating-point exception - erroneous arithmetic operation.

Backtrace for this error:
#0 0x2aaaac2e786f in ???
#1 0x2aaaad033b3f in ???
#2 0x2aaaad0380ca in ???
#3 0x1fbc391 in vspow_
at /glade/.../WRF_DEBUG/WRF/frame/libmassv.f90:371
#4 0x1e615f5 in __module_big_step_utilities_em_MOD_calc_p_rho_phi
at /glade/.../WRF_DEBUG/WRF/dyn_em/module_big_step_utilities_em.f90:1061

I used to get CLF errors as well when I increased vertical levels to 180, from 65, and no matter how much I reduced the time step, it didn't help at all. After reducing vertical levels to 148 in namelist.V_interp, I am getting this error with vspow and no CLF. The current time step is 1.5 seconds for horizontal resolution of 450 m.
I was wondering why I'm getting this error and whether it has anything to do with boundary conditions being shocked. I started the LES domains 12 hours after the initial run in order to avoid that problem and had consulted WRF-help before in order to check the wrfbdy file, and apparently, it looks just fine.
Thanks a lot,
Can you build WRF in debug mode (i.e., ./clean -a, then ./configure -D and ./compile em_real). If the model crashed, this option will output the line number in the specific code where the model crashed, from where you can further track down what is wrong.

Thanks for your response. The above error is indeed from WRF in compiled in Debug mode. The error is from vspow from "frame/libmassv.f90", line, 371,

subroutine vspow(z,y,x,n)
real*4 x(*),y(*),z(*)
do 10 j=1,n
10 continue

and later dyn_em/module_big_step_utilities_em.f90 line 1061:

CALL vspow ( p(its,k,j), temp(its), cpovcv_v(its), itf-its+1 )

The "erroneous arithmetic operation" is obviously arising from temp**cpovcv_v. But I don't understand what needs to be done to fix the error.
Please print the values of p(its,k,j), temp(its), cpovcv_v(its), itf-its+1temp and its, k, j in dyn_em/module_big_step_utilities_em.F . I am suspicious that some of them are unreasonable. Once you know which variable at what points goes wrong, you can further track down to the origin of the errors.

Ming Chen