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Changes in NAM hybrid sigma-pressure Alaska, Hawaii, and CONUSnest files

Posted: March 24th, 2017, 10:28 am
by barbara.stunder
Effective with model output valid 20170321, coinciding with the NAM upgrade at NCEP, there are changes to some of the ARL NAM hybrid-sigma-pressure-level archive and forecast files:

Archives ftp://arlftp.arlhq.noaa.gov/archives/nams/ (see http://ready.arl.noaa.gov/archives.php)

(1) Alaska "nams" archive files have different horizontal domain and filesize than previously. The map projection for Alaska is different but the horizontal grid size is approximately the same. Example filename 20170321_hysplit.t00z.namsa.AK

(2) Hawaii "nams" archive files have different horizontal domain and filesize than previously. Horizontal grid size is 2.5 km instead of 2.0 km. Example filename 20170321_hysplit.t00z.namsa.HI

Forecst files in day subdirectory to ftp://arlftp.arlhq.noaa.gov/forecast/
(see http://ready.arl.noaa.gov/READYmetdata.php)

(1) Alaska "nams" files as above, except example filename hysplit.t00z.namsf.AK

(2) Hawaii "nams" files as above, except example filename hysplit.t00z.namsf.HI

(3) CONUS nest "nams" forecast files are much larger because the grid resolution is 3 km instead of 4 km. Example filename for 48-h file hysplit.t00z.namsf.CONUS. Time-extracted files with 6 hours of model output example filename hysplit.t00z.namsf00.CONUS

Any questions should be addressed on one of the HYSPLIT Meteorologial Data Forums. Thank you.

HYSPLIT Development Team