Ensemble-based precipitation forecasts gave relatively high probability
values for the half and one inch
thresholds for the 24-hr period ending 031312 for the Gulf states with
1 through 8 days lead time. The corresponding observed
precipitation amounts indicate that the forecasts were rather successful.
The high predictability in precipitation was associated with high confidence
(and well verifying) forecasts for 500 hPa height. The cut-off
low over the SW US that allowed Pacific air to reach the Gulf of Maxico
at low latitudes (over and south of Baja CA) was well predicted, with high
confidence, at various lead times (see, for example, at 4,
7, and even at 10 days).
Red colors in these charts over the cut-off low correspond to an area associated
with high predictability.