DECEMBER 2006 30-Day Forecast
430 PM EDT Thu. Nov. 30, 2006

Atmospheric patterns, 700 MB and 500 MB height anomalies, statistical
data, and various models, along with observed cases from past such
months and also data from 1895-2000 were used in this forecast.

A warm phase has developed in the equatorial Pacific and this phase is
forecast to continue. Sea surface temperatures are more than 1C above
normal along the Equator and in an area from 170E to the South American
coast. Anomalies are also in excess of 2C in some locations. Sea
surface temperatures are well above normal from the surface to 100
meters in the eastern Pacific and to depths of 200 meters near the Date
Line. In addition, the heat content is ample enough to sustain above
normal sea surface temperatures.

The NAO is currently in a positive phase and is forecast to remain
positive during the next two weeks. The PNA is currently in a negative
phase and is forecast to trend towards positive for the same period. AO
also positive and is forecast to trend towards negative. The 500-HPA
circulation is forecast to consist of strong positive heights
associated with a ridge across western North America. Negative heights
along with a strong mid-latitude flow across the Pacific to the West
coast. A trough will be in the East. The subtropical ridge is forecast
to be located in the eastern Atlantic with below normal heights in the
western Atlantic. Heights are forecast to remain generally below normal
across eastern North America and the North Atlantic. This is the
reflection of a positive phase of NAO and a positive phase of the PNA.

Above normal temperatures are forecast for the Rockies westward. The
probability of above normal temperatures in this region is 58 percent.
Below normal temperatures are forecast for across the Great Lakes, the
Ohio Valley, the mid-Atlantic and the Northeast. The probability of
below normal temperatures across this region is 56 percent. The
remainder of the nation is expected to average near normal with no
significant deviation from normal climatology.

Above normal precipitation is forecast for the Northwest and into
western Montana. The probability of above normal precipitation in this
region is 57 percent. Above normal precipitation is also forecast
across southern California and the southern Rockies. The probability of
above normal precipitation in this area is 58 percent. Below normal
precipitation is forecast for the northern and central Plains. The
probability of below normal precipitation in this region is 56 percent.
Another area of above normal precipitation is forecast from the central
Gulf coast northeastward. The probability of above normal precipitation
in this region is 56 percent. The remainder of the nation is expected
to average near normal with no significant deviation from normal
climatology.

Jim Munley Jr.
http://www.geocities.com/jimmunleywx