The Winter Storm Severity Index at the Weather
Prediction Center (57)
Joshua Kastman, CIRES/WPC,
College Park, MD
James Nelson, WPC
Mark Klein, WPC
Sarah Perfater, IMSG/WPC
Abstract:
Beginning in October 2017 The
Weather Prediction Center (WPC) took over responsibilities for the running the
Winter Storm Severity Index (WSSI) from the National Weather Service (NWS)
Burlington, VT weather forecast office (WFO). This was done to provide a more
stable processing environment with increased computer and development
resources. The WSSI is a tool designed to assist NWS operational forecasters in
maintaining situational awareness of the possible significance of winter
weather related impacts based upon the current official forecast.
The WSSI is achieved through
the use of Geographic Information Systems (GIS) by screening the official
National Weather Service gridded forecasts from the National Digital Forecast
Database (NDFD) for winter weather elements and combining those data with
non-meteorological or static information datasets (e.g., climatology, land-use,
population) to create a graphical depiction of anticipated overall impacts to
society due to winter weather. The WSSI has been developed to have a two-fold
focus. One is as a tool to assist NWS operational forecasters in maintaining
situational awareness of the possible significance of weather related impacts
based upon the current official forecast. The second is to enhance
communication to external partners, media and general public of the expected
severity (potential societal impacts) and spatial distribution of winter
weather.
Focus will be paid to ongoing
developments of the WSSI at WPC. These developments include breaking the WSSI
into 24 hours periods from the total 72 hour summary, including additional
parameters (apparent temperature, wind speed and snow rates) and making the
data available in GIS formats (KML, Shapefiles). Some examples from the
2017-2018 winter will be shown to highlight strengths and areas needing
improvement.