(Des Moines) The National Weather Service is slightly changing how it issues winter storm warnings. In the Contiguous US, warning criteria thresholds for heavy snow, measured in inches, have been updated to serve as the basis for winter storm watches and warnings.
Kristy Carter of the National Weather Service in Des Moines says previously, the warnings were more time-based, for instance, six inches in 12 hours or eight inches in 24 hours. The new system takes out the time base and focuses on only six and five inches for the counties along the Iowa-Missouri border.
The updates improved decision support services, collaboration, and communication. An interactive heavy snow criteria map is now centrally updated and managed, allowing users to find their local criteria easily. Minor changes to standards should have only a limited impact on end users. Offices can still issue watches and warnings based on anticipated results.
Carter says they are watching the possibility of some snow after Thanksgiving; however, it is too far out to predict how much or if any snow will fall.
