Improved weather decision services were showcased during a high impact winter storm that affected the southwestern U.S. during the week of January 18 through 23, 2010. The winter storm produced record snowfall and rainfall, widespread flash flooding, numerous high wind reports, and tornadoes. NWS Weather Forecast Offices (WFOs) in California, Nevada and Arizona provided up to one week advance notice of the high impact event through new and improved decision support services like graphical weather stories, recorded webinars, GoToMeetings, and direct on-site weather decision Emergency Operations Center support. The Global Ensemble Forecast System (GEFS) standardized anomalies were utilized to raise forecaster confidence of the historic winter storm. The user and partner response was very complimentary and favorable after the week long winter storm.