diff --git a/modules/aeolus/aeolus_amv.py b/modules/aeolus/aeolus_amv.py
index 535060fe7db0aa881cc57d1062c88b89d05f3243..6e7da8a8e89f23406078088d55c2ca4259a89509 100644
--- a/modules/aeolus/aeolus_amv.py
+++ b/modules/aeolus/aeolus_amv.py
@@ -942,7 +942,7 @@ def analyze2(amvs_list, bf_list, raob_match_list, bf_gfs_list, amv_prod_list):
                       np.average(np.abs(bin_spd[i])), np.average(bin_spd[i]), np.average(np.abs(bin_dir[i])), np.average(bin_dir[i])))
 
 
-def compare_amvs_bestfit(amvs, bfs):
+def compare_amvs_bestfit(amvs, bfs, bin_size=200):
     didx = 4
     sidx = 3
     pidx = 2
@@ -950,7 +950,6 @@ def compare_amvs_bestfit(amvs, bfs):
     vld_bf = bfs[:, 3] == 0
     keep_idxs = vld_bf
 
-    bin_size = 200.0
     bin_ranges = get_press_bin_ranges(50, 1050, bin_size=bin_size)
 
     amv_p = amvs[keep_idxs, pidx]