Index: wflow-py/wflow/wf_netcdfio.py
===================================================================
diff -u -rf48b5321292915b892132463b750dbda2998e3cb -r059f8f8f9f823ea6bdd45447a640c989b3b85b5d
--- wflow-py/wflow/wf_netcdfio.py	(.../wf_netcdfio.py)	(revision f48b5321292915b892132463b750dbda2998e3cb)
+++ wflow-py/wflow/wf_netcdfio.py	(.../wf_netcdfio.py)	(revision 059f8f8f9f823ea6bdd45447a640c989b3b85b5d)
@@ -332,12 +332,14 @@
         timeList = date_range(starttime, end, timestepsecs)
         self.timestepbuffer = zeros((self.maxbuf, len(y), len(x)))
         self.bufflst = {}
+        self.buffdirty = False
 
         globmetadata.update(metadata)
 
         prepare_nc(self.ncfile, timeList, x, y, globmetadata, logger, Format=self.Format, EPSG=EPSG,zlib=self.zlib,
                    least_significant_digit=self.least_significant_digit)
 
+
     def savetimestep(self, timestep, pcrdata, unit="mm", var='P', name="Precipitation"):
         """
         save a single timestep for a variable
@@ -386,9 +388,11 @@
 
         if self.bufflst.has_key(var):
             self.bufflst[var][bufpos, :, :] = data
+            self.buffdirty = True
         else:
             self.bufflst[var] = self.timestepbuffer.copy()
             self.bufflst[var][bufpos, :, :] = data
+            self.buffdirty = True
 
         # Write out timestep buffer.....
 
@@ -398,6 +402,7 @@
                 "Writing buffer for " + var + " to file at: " + str(spos) + " " + str(int(bufpos) + 1) + " timesteps")
             nc_var[spos:idx + 1, :, :] = self.bufflst[var][0:bufpos + 1, :, :]
             self.nc_trg.sync()
+            self.buffdirty = False
 
     def finish(self):
         """
@@ -408,6 +413,8 @@
         if hasattr(self, "nc_trg"):
             self.nc_trg.sync()
             self.nc_trg.close()
+            if self.buffdirty:
+                self.logger.error('Finishing with dirty netcdf write buffer...!')
 
 
 class netcdfinput():