Communicating Potential High-Impact/Sub-Advisory
Winter Events (295)
Christopher A Strong, NOAA/NWS/WFO,
Sterling,
James E Lee, NOAA/NWS/WFO
Steven M Zubrick, NOAA/NWS/WFO
Brian J LaSorsa, NOAA/NWS/WFO
Abstract:
Small amounts of snow over
urban areas have the potential to create massive commuter gridlock when
conditions are right. These small amounts of snow are often difficult to
forecast. Forecaster confidence in occurrence of these events often comes after
the point at which Departments of Transportation can be effective at mitigating
the threat.
During the winters of 2016-17
and 2017-18, the National Weather Service's Baltimore Washington Weather
Forecast Office (WFO-Sterling) collaborated with their regional transportation
partners and the Office of Personnel Management (OPM) to create and test an
experimental &ldquoPotential Winter Commuting Hazard&rdquo statement.
The purpose of this statement, with its associated notifications, is to alert
the community to the threat of a potential high-impact winter transportation
event, with enough advance notice for society to take effective actions to
mitigate the impact. This is often done many hours before there is enough
confidence to issue formal warnings or advisories, and furthers our goal of
communicating potential impacts to the public and core customers.
This presentation will
describe what conditions are needed for a high impact traffic disruption from a
minor winter precipitation event, what process the forecasters use to notify
the community to the threat, and the necessary education component. There is
also a real-world comparison of how the Washington D.C. metro area was severely
affected from a January 20th 2016 event, versus the minor impact from a very
similar event on January 4th, 2018.