October 2007 30-DAY OUTLOOK
530 PM EDT Mon. October 1, 2007
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.
During the past couple of months, negative sea surface anomalies has
extended westward to near the Date Line. The upper ocean heat content
in the upper 300 meters in the central and eastern equatorial Pacific
are 1 to 4C below normal. The low-level easterlies are stronger than
normal in the west-central equatorial Pacific. Convection remains
suppressed throughout the central and eastern equatorial Pacific.
Convection was enhanced across parts of the far western Pacific.
Conditions indicate La Nina conditions and at the present time, it is
expected that a weak La Nina will occur and will have little if any
impact on the circulation across the nation.
NAO is currently negative positive and is forecast to trend negative
by mid-month. The PNA is positive and is forecast trend towards
negative during much of the two week period but trend towards positive
by the end of the same period. Models are in fairly good agreement
with the 500-HPA circulation across North America. A deep trough will
be across the north Pacific, and a ridge will be across the central
part of the nation.
Most statistical models support above normal temperatures across a
large area of the nation. Below normal temperatures are forecast
across the Northwest into the northern Rockies. The probability of
below normal temperatures across this region is 58 percent. Above
normal temperatures are forecast across the eastern portion of the
Southwest, the central and southern Plains, the Ohio and Tennessee
Valleys, the Southeast, the mid-Atlantic and the Northeast. The
probability of above normal temperatures in this region is 57 percent.
The remainder of the nation is expected to average near normal with no
significant deviation from normal climatology.
Above normal precipitation is forecast across the Northwest. The
probability of above normal precipitation in this area is 57 percent.
Below normal precipitation is forecast across much of the Rockies, and
the Plains. The probability of above normal precipitation across this
region is 57 percent. Above normal precipitation is expected along the
gulf and Southeast coast. The probability of above normal
precipitation across this area is 57 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