4th July 20:30
February 2006 30-Day Forecast
FEBRUARY 2006 30-DAY OUTLOOK
500 PM EST Tue. January 31, 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.
Equatorial sea surface temperature anomalies of greater than +0.5ºC
were observed confined to the region between Indonesia and 165ºE,
while negative anomalies less than -0.5ºC were observed at most
locations between the date line and the South American coast. During
the last several months surface and subsurface temperature anomalies
have decreased in the region between 180ºW and the South American
coast. During the same period persistent stronger than normal low-level
equatorial easterly winds were observed over the central Pacific. This
is a persistent pattern of enhanced tropical convection near Indonesia
and suppressed convection near the date line. Collectively, the present
oceanic and atmospheric anomalies are consistent with the development
of La Nina conditions in the tropical Pacific.
Both NAO and AO are currently in a negative Phase and forecast to
remain negative through the next two weeks. The PNA is currently
positive and is forecast to be positive through the same period. This
pattern favors generation of cold air masses at the high latitudes and
will increase the likelihood of storminess across the mid-latitudes.
The 500 MB pattern is forecast to consist of above normal heights in
the high latitudes and below normal heights in the mid-latitudes. Below
normal heights are also expected across Alaska. Above normal heights
are forecast across the eastern Pacific and across much of western
North America northeast through Canada and into the North Atlantic. A
longwave trough is forecast near the East coast.
Above normal temperatures are forecast across the Rockies westward to
the Pacific coast. The probability of above normal temperatures in
this region is 59 percent. Below normal temperatures are forecast
across the upper Mississippi Valley and the Ohio Valley eastward across
the Northeast and the northern mid-Atlantic. The probability of below
normal temperatures across this region is 56 percent. The remainder of
the nation is likely to average near normal with no significant
deviation from normal climatology.
Above normal precipitation is forecast for the Northwest from northern
California northward. The probability of above normal precipitation in
this region is 58 percent. Below normal precipitation is forecast for
much of the Rockies and the Plains. The probability of below normal
precipitation is 58 percent. Above normal precipitation is forecast for
the middle Ohio Valley, the mid-Atlantic states and southern New
England. 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 G. Munley, jr.,