They were probably using Rwy 13 because of low visibility.
Winds aloft from National Weather Service Radiosonde at 1200Z at Upton Long Island(about 40 nautical miles east of LGA) were reported from 020 degrees at 10 knots true at the surface, from 350 degrees at 16 knots true at 414 feet msl and from 350 degrees at 22 knots true at 1000 feet msl .
According to FlightAware Delta 1086, a MD-88, from ATL arrived LGA at 1556Z
METARs
KLGA 051751Z COR 30015G21KT 1/4SM R04/2200V2800FT +SN FZFG VV007 M05/M07 A3017 RMK AO2 TWR VIS 1/4 SLP217 931040 4/007 933015 SNINCR 1/7 P0004 60028 T10501067 10006 21050 53010 $
KLGA 051716Z 33013KT 1/4SM R04/2000V2400FT +SN FZFG VV009 M04/M06 A3016 RMK AO2 TWR VIS 1/4 P0002 $
KLGA 051651Z 32016KT 1/4SM R04/2800V4000FT SN FZFG FEW006 OVC012 M03/M05 A3015 RMK AO2 SLP210 P0005 T10331050 $
KLGA 051640Z 32014KT 1/4SM R04/2400V4000FT SN FZFG SCT007 OVC012 M03/M05 A3015 RMK AO2 SFC VIS 1/2 PRESRR P0005
KLGA 051631Z 36009KT 1/4SM R04/3500VP6000FT SN FZFG VV012 M03/M05 A3012 RMK AO2 SFC VIS 1/2 P0004
KLGA 051622Z 01008KT 1/4SM R04/3000VP6000FT SN FZFG VV011 M03/M05 A3012 RMK AO2 SFC VIS 1/2 P0003
KLGA 051551Z 01008KT 1/4SM R04/2800V3500FT SN FZFG VV009 M03/M05 A3012 RMK AO2 SLP199 P0006 T10331050
KLGA 051524Z 04007KT 1/4SM R04/2600V2800FT SN FZFG VV009 M03/M04 A3013 RMK AO2 P0004
KLGA 051451Z 03010KT 1/4SM R04/3000V4500FT SN FZFG VV012 M03/M04 A3014 RMK AO2 TWR VIS 3/4 SLP207 P0003 60013 T10281044 53040
KLGA 051417Z 03012KT 1/4SM R04/2800V4000FT SN FZFG SCT006 OVC012 M02/M03 A3011 RMK AO2 TWR VIS 3/4 P0002
KLGA 051351Z 01014G18KT 1/2SM R04/5000VP6000FT SN FZFG FEW006 OVC014 M02/M03 A3011 RMK AO2 TWR VIS 3/4 SLP195 SNINCR 1/5 P0005 T10171033
KLGA 051338Z 01013KT 1/2SM R04/3000V5000FT SN FZFG SCT006 OVC010 M02/M03 A3010 RMK AO2 TWR VIS 3/4 P0005
KLGA 051333Z 36011KT 1/4SM R04/3000V5000FT SN FZFG VV007 M01/M03 A3010 RMK AO2 TWR VIS 3/4 PRESRR P0004
KLGA 051251Z COR 34006KT 1/4SM R04/3000V4000FT SN FG OVC009 00/M01 A3006 RMK AO2 TWR VIS 3/4 SLP178 SNINCR 1/4 P0005 T00001011
KLGA 051218Z 33007KT 1/4SM R04/3500V4500FT SN FG BKN009 OVC014 00/M01 A3004 RMK AO2 TWR VIS 3/4 P0002
KLGA 051208Z 33007KT 1/2SM R04/4000V5500FT SN FG FEW006 OVC011 00/M02 A3004 RMK AO2 TWR VIS 3/4 P0001
KLGA 051157Z 33007KT 1/2SM R04/5000VP6000FT SN FG BKN010 OVC015 01/M02 A3003 RMK AO2 TWR VIS 3/4 P0000
KLGA 051151Z 33007KT 1SM R04/5500VP6000FT -SN BR BKN011 OVC016 01/M02 A3003 RMK AO2 SLP167 931004 4/003 P0002 60016 70046 T00061017 10044 20006 53014
Last edited by airman1900; 5th Mar 2015 at 18:03.
Reason: Added more METAR data