National Weather Service
|National Operational Hydrologic
Remote Sensing Center
National Snow Analyses
Note: these data are unofficial and provisional.
An assimilation was performed 3/6/2013 for the Mid-Atlantic and Northeastern United States using recent observations from the NYCDEP, NEACE, and additional SWE reporting observers to adjust SWE within the snowpack. Across Ohio, Central New York, and Southern Maine water was removed from the snow pack due to the model overestimating snow precipitation. In these areas between 0.4 to 2 inches of water was removed from the snowpack. In parts of Pennsylvania, Virginia, Northern New York, Vermont, and New Hampshire water was added to the snowpack after the model underestimated snow precipitation associated with the recent winter storm (3/5-3/6). In these areas between 0.5 to 3 inches of water was added to the snowpack. This area will be reviewed again today (3/7) as new observations become available to adjust the snowpack accordingly due to the recent winter storm event.
An assimilation was performed 3/4/2013 for both East and West CONUS to adjust water levels within the snowpack. In the Eastern United States throughout much of the region water was removed from the snow pack, while in the Western United States water was added to the snowpack.
In the Northeast and Central Midwest the model overestimated precipitation and required water to be removed from the snowpack. In the Northeast up to 1 inch of water was removed, in Michigan up to 0.5 inches of water was removed, and across Iowa, Missouri, and Kansas up to 1 inch of water was also removed. Along the coast in the Northeast the model overestimated melt and required up to 1.75 inches of water to be added to the snowpack in parts of Massachusetts, Connecticut, and New Hampshire.
The largest amounts of water were added to snowpacks in the Sierra Nevadas, up to 3 in; Cascades, up to 4 in; Eastern Oregon, up to 1.25 inches ; and Southwest Idaho, up to 2 inches. In these areas the model had overestimated snowmelt. Two notable locations where water was removed from the snowpack in the West include the Yellowstone Region and the western side of the Colorado Front Range. In these areas up to 1 inch of water was removed due to the model overestimating snow precipitation.
The large winterstorm moving across the Midwest into the Mid Atlantic region will continue to alter the snowpack as it progresses eastward. Incoming observations will continue to be monitored and the model will be assimilated as necessary to adjust snow water levels as the storm moves across the region.
The Airborne program has no scheduled flights in this region for the week of March 11, 2013.