Intermediate File Format: SI

Record 1:  IFV
Record 2:  HDATE, XFCST, MAP_SOURCE, FIELD, UNITS, DESC, XLVL, NX, NY, IPROJ
  if (IPROJ == 0) (Cylindrical equidistant projection)
        Record 3:  STARTLOC, STARTLAT, STARTLON, DELTALAT, DELTALON
  else if (IPROJ == 1) (Mercator projection)
        Record 3:  STARTLOC, STARTLAT,STARTLON, DX, DY, TRUELAT1
  else if (IPROJ == 3) (Lambert conformal projection)
        Record 3:  STARTLOC, STARTLAT, STARTLON, DX, DY, XLONC, TRUELAT1, TRUELAT2
  else if (IPROJ == 5) (Polar-stereographic projection)
        Record 3:  STARTLOC, STARTLAT, STARTLON, DX, DY, XLONC, TRUELAT1
  endif
Record 4:  SLAB

Where:

    IFV

    integer

    intermediate-format version number for WRFSI is 4

    HDATE

    character (LEN=24)

    The time, in format "YYYY-MM-DD_HH:mm:ss    
    " (only the first 19 characters are used)

    XFCST

    real

    Forecast time (in hours) of the data in the slab

    MAP_SOURCE

    character (LEN=32)

    Source of data

    FIELD

    character (LEN=9)

    A field name.  Names with special meaning are described below.

    UNITS

    character (LEN=25)

    Units describing the field in the slab.

    DESC

    character (LEN=46)

    Text description of the field in the slab.

    XLVL

    real

    Pressure-level (Pa) of the data.  200100 Pa indicates surface data; 201300 Pa indicates sea-level pressure

    NX

    integer

    Slab dimension in the X direction

    NY

    integer

    Slab dimension in the Y direction

    IPROJ

    integer

    Flag denoting the projection.  Recognized values are:
         0:  Cylindrical Equidistant (Lat/lon) projection.
         1:  Mercator projection.
         3:  Lambert-conformal projection.
         5:  Polar-stereographic projection.

    STARTLOC

    character (LEN=8)

    Start location of data. Could be "CENTER" or "SWCORNER". "SWCORNER" is typical.

    STARTLAT

    real

    Starting latitude (degrees north)

    STARTLON

    real

    Starting longitude (degrees east)

    DELTALAT

    real

    Latitude increment (degrees) for lat/lon grid

    DELTALON

    real

    Longitude increment (degrees) for lat/lon grid

    DX

    real

    Grid-spacing in x (km at TRUELAT1 (and TRUELAT2 as appropriate))

    DY

    real

    Grid-spacing in y (km at TRUELAT1 (and TRUELAT2 as appropriate))

    XLONC

    real

    Center longitude of the projection

    TRUELAT1

    real

    Extra latitude (degrees north) used for defining Mercator, Polar Stereographic, and Lambert conformal projections

    TRUELAT2

    real

    A second extra latitude (degrees north) used for defining Lambert conformal projection

    SLAB

    real, dimension(NX,NY)

    Two-dimensional array of data.