NMME
ensemble contains 79 members, all weighted
equally.
A/B/N [Above/Below/Neutral]
are terciles.
* A and B contours
show when one class has >38% of ensemble members, and the opposite class is
below 33%.
* In the
case that A is >38% and N is >33%, A will be shown. This is the same for B.
* N contours
show when >38% of ensemble members fall in the “Neutral” tercile,
and both A and B are below 33%.
* White
areas show where no one class is dominant: either all terciles
are under 38%, or both A and B are over 38%.
The tercile limits were determined separately for
each model using the NMME hindcasts (1982-2010
). For tmp2m and sst, the mean
and standard deviation were found for each model and terciles
set as mean +/- 0.43sd. For precipitation, thresholds were determined by
ranking all hindcasts and taking the 66th and 33rd percentiles.
Then, the number of ensemble members in each model that fell into the separate
categories (relative to their own distributions) were tallied up.