.
To advance one frame, use the Plus 1
button 
. To resume looping,
use the Forward button 
. Loop
speed is increased by repeatedly clicking the Fast button 
and
decreased by doing the same to the Slow button 
.During the day 3-7 time frame, the MREFs have been used to determine the large scale flow (and given the likely flow, the risk of winter weather in that particular regime). Toward the short end of that range, the specific features that may result in significant winter weather can be assessed.
The SREFs start where the MREFs leave off in the day 2-3 time frame. At NCEP, they are run at higher resolution than the MREFs and the deterministic global forecast model, but at coarser resolution than the operational mesoscale model. They can be used to assess the risk of significant winter in various parts of a NWS weather forecast office (WFO) county warning area (CWA), through making use of appropriate SREF post-processed output.
The purpose of this case is to give the forecaster an example of how to:
1.Use the SREFs to refine forecasts for regions that the day three MREF
indicated were threatened by winter weather.
2.Understand how to use SREF data to quantify the uncertainty in the severity
of winter weather.
3.Understand limitations of the SREFs with respect to details of significant
winter weather that may take place, including known ensemble system deficiencies.
In going through this case, when you open a separate graphic, an image or
loop will pop up in a separate window. If one is already displaying, it will
be replaced by the one you just selected. Loops automatically start looping.
To freeze a frame, click the Stop button .
To advance one frame, use the Plus 1
button . To resume looping,
use the Forward button . Loop
speed is increased by repeatedly clicking the Fast button and
decreased by doing the same to the Slow button .
by Dr. Bill Bua