The Weather Forecasting Forum

I tried importing some data under the GRIB directory of the NDFD (http://www.nws.noaa.gov/ndfd/), but have trouble getting it loaded. It gives the error message:

This GRIB data needs bitmap mask table 21 provided by the forecast center.

Any clues what this means?

It means a non-zero value was seen in code table 6.0: Bitmap flags:
http://www.nws.noaa.gov/tdl/iwt/grib2/doc.htm#code6.0

"A bit map pre-determined by the originating/generating Centre applies to this product and is not specified in this Section."

If you can tell me the URL where you're getting the data I might be able to take a closer look and see if anything can be done.

Tim