NASA LaRC GOES Satellite Imagery File Naming Convention:

GOES East Imagery: 

G13.YYYYDDD.HHMM.##KM.C##.GIF

where,
G13       =             GOES-13 Satellite
YYYY      =             Year
DDD       =             Julian Day
HH        =             Hours (UTC)
MM        =             Minutes (UTC)
##KM      =             Pixel Size (kilometers)
C##       =             Channel Number:
                              C01 = Ch. 1, 0.63 um band
                              C03 = Ch. 3, 6.5 um band
                              C04 = Ch. 4, 10.7 um band
                              C2-4 = Difference between 3.9 and 10.7 um bands (Ch.2-4)
                              C4C = Ch. 4, 10.7 um band in color
                              C4RC =  Ch. 4, 10.7 um band in RGB color
GIF       =             Graphics Interchange Format file extension (or alternatively .KML for Google Earth)

GOES-13 Cloud Products:

G13.NAAMES.YYYYDDD.HHMM.##KM.VALUE.GIF

where,
G13       =             GOES-13 Satellite
YYYY      =             Year
DDD       =             Julian Day
HH        =             Hours (UTC)
MM        =             Minutes (UTC)
##KM      =             Pixel Size (kilometers)
VALUE     =             Cloud Product Name:
                              DEFF = Effective Ice Diameter
                              IWP = Ice Water Path
                              LWP = Liquid Water Path
                              PHAS = Cloud Phase
                              REFF = Effective Water Radius
                              RGB = False Color Image (see image caption)
                              TAU = Optical Depth
                              TEFF = Effective Cloud Temperature
                              ZBOT = Cloud-Base Height
                              ZEFF = Effective Cloud Height
                              ZTOP = Cloud-Top Height
GIF       =             Graphics Interchange Format file extension (or alternatively .KML for Google Earth)


Satellite images courtesy of P. Minnis:  http://satcorps.larc.nasa.gov/