diff --git a/modules/aeolus/aeolus_amv.py b/modules/aeolus/aeolus_amv.py
index d947a46ed21a5bc691e8928624df7b72d7d1ea0c..25cd5ba89ddd159a3569ed25cd84a7a0cf13d187 100644
--- a/modules/aeolus/aeolus_amv.py
+++ b/modules/aeolus/aeolus_amv.py
@@ -2118,6 +2118,8 @@ def create_bestfit_file(filename, match_dct, raob_dct, raob_ts, gfs_at_raob_dct,
     dist_to_raob = rootgrp.createVariable('dist_to_raob', 'f4', ['time', 'num_raob_profs', 'max_num_amvs'])
     dist_to_raob.units = 'km'
 
+    amv_source_index = rootgrp.createVariable('amv_source_index', 'f4', ['time', 'num_raob_profs', 'max_num_amvs'])
+
     var_s = rg_exmpl.variables
     for pidx, param in enumerate(amv_params):
         v = var_s[param]
@@ -2225,6 +2227,12 @@ def create_bestfit_file(filename, match_dct, raob_dct, raob_ts, gfs_at_raob_dct,
 
         dist_to_raob[0, idx, 0:num_amvs] = haversine_np(key.lon, key.lat, amvs[:, 0], amvs[:, 1])
 
+        param_s = match_dct.get(key)
+        idx_idx = param_s.shape[0] - 1
+        amv_idxs = param_s[idx_idx, ]
+
+        amv_source_index[0, idx, 0:num_amvs] = amv_idxs[:]
+
     rg_exmpl.close()
     rootgrp.close()