MARCH 2011 30-DAY OUTLOOK
545 PM EST Mon. Feb. 28, 2010
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 cold episode conditions continue across the tropical Pacific with
Sea surface temperatures near the equator in the eastern and central
Pacific ocean are 1 to 2 degrees C below normal from about 160Ee to
120W. Below normal sea surface temperatures extend from 20N to 20S
latitude over much of the eastern
Pacific. Sea surface temperatures from 120W to the South American
coast have warmed during the last month from below the -1.5 C anomaly
to near the normal. The subsurface ocean heat content from near
equatorial average temperatures in the upper 300 meters continues to
be below normal in the east Pacific, while above normal anomalies in
the west Pacific have expanded eastward. The large scale atmospheric
circulation over the tropical Pacific ocean continues to indicate a
cold episode. Convection remained enhanced over Indonesia and
suppressed over the western and central equatorial Pacific. Low level
easterly trade winds are enhanced over the west Pacific, as are
westerly wind anomalies in the upper levels over the western and
central Pacific.

The NAO index is positive and is forecast to trend towards neutral by
day 10 and remain neutral to slightly positive through day 14. The NAO
is negative and is forecast to remain negative through day 14. The AO
is positive and is forecast to remain positive through day 14. Models
are in good agreement on the expected 500-hpa circulation for March. A
ridge is forecast over much of Alaska with an extension of positive
height anomalies south results in a moderately deep trough near the
West coast. Above normal heights are expected across the southern
U.S.

Below normal temperatures are forecast for much of the West except for
southern California and thye southern Rockies. The probability of
below normal temperatures in this area is 57 percent. Above normal
temperatures are forecast for the southern Plains, the lower
Mississippi Valley and the lower mid-Atlantic. The probability of
above normal temperatures in this is high 57 percent. The remainder of
the nation is expected to be near normal with no significant deviation
from climatology.
Above normal precipitation is forecast for the Northwest and the
northern Rockies. The probability of above normal precipitation in
this area is 57 percent. La Nina will likely impact precipitation
across the southern Rockies, the southern Plains and the lower
Mississippi Valley. The probability of below normal precipitation in
the area is 57 percent. Above normal precipitation is forecast for
the Northeast and the mid-Atlantic. The probability of above normal
precipitation for this area is 56 percent. The remainder of the nation
is expected to be near normal with no significant deviation from
climatology.
Jim Munley Jr.
http://www.jimmunleywx.com