GFS and NAM MOS BUFR Guidance
On or about August 3, 2010, MDL will be making changes to both the short-range and extended-range GFS MOS BUFR
(Binary Universal Form for the Representation of meteorological data) messages. In the short-range GFS MOS BUFR
message, the sky cover guidance will change from total sky cover to opaque sky cover. This change has already been
made in the text messages (see TIN 07-34
for more details). No changes are required to the descriptors in the BUFR file.
In the extended-range GFS MOS BUFR, several changes are being made. The sky cover guidance is changing to opaque
sky cover valid every 3 h on the hour (analogous to what is available in the short-range GFS MOS BUFR messages),
replacing a proposed opaque sky cover guidance system which covered 3-h periods but was never developed or populated.
Similarly, a proposed 5-category precipitation type system which covered 3-h periods but was never developed or
populated is being replaced with a 3-category precipitation type system valid every 3 h on the hour. This is also
analogous to what is available in the short-range GFS MOS BUFR messages. These changes will require modifications
to the descriptors in the BUFR messages. See the documentation below in the References section for more details.
Additionally, guidance for temperature, dewpoint, u- and v-wind components, wind speed, and wind direction will
now be available every 6 h from 198 to 264 h. 12-h PoP will be available every 12 h from 204 to 264. Maximum and
minimum temperature will be available for three additional projections as well. Finally, two more projections will
be available for snowfall guidance.
The BUFR messages contain a more complete set of MOS forecasts than what is found in the MAV, MEX, and MET
alphanumeric bulletins. BUFR messages will include all of the probabilities for precipitation amount, sky cover,
ceiling height, visibility, obstruction to vision, precipitation type, and snowfall, as well as their respective
categorical forecasts. Additionally, the BUFR messages include guidance products not found in the alphanumeric
bulletins, including probability of precipitation occurrence, and conditional precipitation characteristic. The
stations included in these messages are the same as the MAV, MEX, and MET bulletins, and can be found at
The GFS MOS bulletins use these headers:
Short-range (6 - 84 h products):
- JSML30 KWNO - Pacific Region
- JSML31 KWNO - Northeast CONUS
- JSML32 KWNO - Southeast CONUS
- JSML33 KWNO - North-Central CONUS
- JSML34 KWNO - South-Central CONUS
- JSML35 KWNO - Rocky Mountain CONUS
- JSML36 KWNO - West Coast CONUS
- JSML37 KWNO - Alaska
- JSML38 KWNO - Western Pacific Islands
Extended-range (6 - 192 h products):
- JSMT30 KWNO - Pacific Region
- JSMT31 KWNO - Northeast CONUS
- JSMT32 KWNO - Southeast CONUS
- JSMT33 KWNO - North-Central CONUS
- JSMT34 KWNO - South-Central CONUS
- JSMT35 KWNO - Rocky Mountain CONUS
- JSMT36 KWNO - West Coast CONUS
- JSMT37 KWNO - Alaska
The NAM MOS bulletins use these headers:
- JSML10 KWNO - Pacific Region
- JSML11 KWNO - Northeast CONUS
- JSML12 KWNO - Southeast CONUS
- JSML13 KWNO - North-Central CONUS
- JSML14 KWNO - South-Central CONUS
- JSML15 KWNO - Rocky Mountain CONUS
- JSML16 KWNO - West Coast CONUS
- JSML17 KWNO - Alaska
What's changing in the short-range GFS (MAV) BUFR?
- Cloud cover in the BUFR switching from total sky cover to opaque sky cover.
What's changing in the extended-range GFS (MEX) BUFR?
- Sky cover and precipitation type categories have been redefined (see below for more details), and will be
available every 3 hours instead of every 12 hours.
- Temperature, dewpoint, Max/Min temperature, wind, and 12-h PoP now available out to 264 h (270 h for max/min).
- Snowfall now available for two more projections.