One is when there is a combination of a fresh cold-air outbreak
and very strong heating.
have provided ample opportunities for credentialed experts to get buried in the avalanche of common credence and flashy headlines.
The Dakotas are affected by strong cold-air outbreaks
as early as August, while in Texas and Oklahoma they are normally not seen until mid-October.
Rather, cold-air outbreaks are most directly related to transient, localized displacements of the edge of the tropospheric polar vortex that may, in some circumstances, be related to the stratospheric polar vortex, but there is no known one-to-one connection between these phenomena.
Despite this statistical link between occurrence of cold-air outbreaks and weak stratospheric vortices, there is not a one-to-one relationship between them.
Because of this, it remains unclear at present if and to what degree the size and/or strength of the hemispheric-scale tropospheric vortex is actually connected with cold-air outbreaks.
Extreme weather events such as cold-air outbreaks (CAOs) pose great threats to human life and the socioeconomic well-being of modern society.
The linkage of the occurrence probability of continental-scale cold-air outbreaks to the amount of air mass transported into the polar stratosphere suggests that it is feasible to predict them 1 month in advance.
Motivated by the work cited above and referenced therein, we here propose a hybrid (dynamical plus statistical) paradigm for predicting the occurrence of individual continental-scale cold-air outbreaks (CAOs) in winter at the subseasonal range (0-30 days).