"Bernard Burton" I think that SST anomalies are of limited value in
forecasting, except on
the local scale. The current SST is a reflection of what has happened to
that area of water in the past. It has a close affinity to the weather
patterns that have existed in in the past few days extending back to weeks
with decreasing amplitude of effect. Long-wave global dynamical patterns
in
the mid-upper troposphere that largely determine the run of events in
mid-latitudes, are reasonably co-herent in the medium term. However, the
dynamics of the mid-upper troposphere is little influenced by small
relatively local SST anomalies compared with the overall inbalances that
naturally exist between the equator and poles.



I think it's worth pointing out that the regime in the North Atlantic sector
depends on the strength of the polar vortex.When the vortex is strong there
is a single strong zonal jet across the NA,during times of weak vortex there
tends to be two weaker jets-eastern and western in the sector.The
statistical dependence on SST distributions differs entirely for the two
different regimes,

--
regards,
David

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