Agenda:

Comments on hw1 and hw2

Text editors (e.g. gedit) vs. word processors (e.g. MS Word)

Directory locations for GEMPAK data files

Most frequently-used directories housing weather data in GEMPAK format on our servers:

Current (1-7 day old typically) Data:

/data1: Raw (typically plain-text, aka ASCII) data

/data1/gempak : Observational data: Surface (.sf), Ship/Buoy (.sb), Synoptic (.sy), RAOB (.ua) files in daily or hourly files

/data1/gempak/hds ($MODEL): Gridded Numerical Weather Prediction (NWP) model data (NAM, GFS, ECMWF, RUC, all generally low-resolution/coarse data

/data7/nmc2: Gridded NWP model data (GFS, NAM, GFS Ensemble) including higher-resolution data:

/data7/nsat, or $SAT: Satellilte Imagery

/data7/nsat/radar/noaaport ($RAD): Level 3 Radar Imagery

Archived (7-365 day old) Data:

/nasdata0/unidata/data1: archive of data found in /data1

/nasdata1/unidata/nmc2: archive of GFS data found in /data7/nmc2

/gfs1/1deganl: archive of 1-degree GFS 0-hr forecast (i.e., analysis) grids, dating back to Feb. 2004

We will access many of the these directories as we explore GEMPAK, NMAP2, NSHARP, and the IDV during the remainder of the semester.

What Is GEMPAK?

GEMPAK: command-line based GEneralized Meteorological Analysis and Display PacKage

Developed at the National Centers for Environmental Prediction's “NOAA Science Center” in Camp Springs, Maryland; refined for the educational community by the Unidata Program Center in Boulder, Colorado

N-AWIPS: National Centers (NCEP) Advanced Weather Interactive Processing System: Graphical (GUI) front-end for GEMPAK

Here are some of the GEMPAK programs that operate on observational data:

sflist: output surface (i.e. METAR, Ship/Buoy, Synop) data in text format

sfl604: similar to sflist, but for a fixed set of parameters

sfmap: Plots surface data for a set of stations on a map.

sfgram: Plots a set of time series of surface data

snlist: output RAOB data in text formnat

snmap: Plots RAOB data at a single level on a map

snprof: Draws a vertical profile of RAOB data, such as a Skew-T

Here are some of the GEMPAK programs that operate on gridded data:

gdinfo: list date/times, levels, vertical coordinate, and parameters in a grid file

gdlist: output numerical values of a gridded field in text format

gdplot3: Plot, contour, and/or fill a variety of scalar and vector fields on a map

gpmap: Draw a map and (optionally) display satellite, radar data, or an NMAP2-drawn product (e.g. a surface analysis) on it

gdprof: Draw a vertical profile of gridded data at a point

gdtser: Plot a time series of gridded data

gdcross: Plot gridded data on a cross-section

gdthgt: Plot a time-height cross section of data