Daily Global Ionosphere Maps GIM-WTEC of the ionosphere weather W-index 
produced from GIM-TEC IONEX MAP:
Geographic coordinates:                       
   87.5 -87.5  2.5    LAT1/ LAT2/ DLAT	     
 -180.0 180.0  5.0    LON1/ LON2/ DLON	     
(1) YRMNDDw.zip : JPL <jplr> GIM-TEC based       
    W-index values in i.u. (index units). 
    0, 1, ... , 23 Hours, UT.    
(2) YRMNDDw_15m.zip : UPC <uqrg> GIM-TEC based
    W-index values in i.u. (index units). 
    00:00, 00:15, 00:30, 00:45, 01:00, ... , 23:45 Hours-15min, UT.