It has been great year so far for snow across the mountains of southern Colorado. Current snowpack (as of Mar 21) across the Gunnison, Upper Rio Grande, and Arkansas River Basins are 152%, 140%, and 147% of normal, respectively. The above normal snowpack is appreciated, as it is coming on the heals of a year in which snowpack was well below normal. These trends are captured in Fig 1.
The snowpack is easily diagnosed in satellite imagery (MODIS imagery here). A ridge of high pressure over the western US allowed for clear views of the snow cover over Colorado on 16 March 2019, several days removed from a significant snowstorm (Fig 2).
Compared to the same day last year (Mar 16, 2018), the improved snow cover is easily apparent (Fig 3).
Next, we look at the trend of snow cover across Colorado on clear days during the 2018/2019 winter (Fig 4).
The National Operational Hydrologic Remote Sensing Center (NOHRSC) runs a model that assimilates satellite data, ground observations, and airborne observations to create daily snow maps. Figure 5 includes a comparison of NOHRSC snow depth for March 16 in 2018 and 2019. The improved snow cover and snow depth is obvious from these images.
Bill Line, NWS
Satellite Liaison Blog 