Note DetailLaNina stronger but...
2/25/2008 12:41:00 PM

La Nina is getting stronger, but also showing age:
The trade winds are weakened from 100-140 degrees
west longitude allowing solar heating of the sea
surface along the equator off the west coast of
South America.  At this point this is not an
indicator of the end of La Nina.  Should it
continue for a few weeks it will indeed result in
an ultimate demise of the event.   Click on
 “What’s happening...”   As of Feb. 25th the SOI is
at its highest 90-day average value for this event
(+1.51) where +0.8 is the threshold that was used
in the analysis of impacts on Corn Belt crop
yields.   The
National Weather Service outlook for March is
typical of La Nina with a tendency to be dry in the
high plains and from southern CA to the
southeastern US.  The summer precipitation outlook
(Jun-Aug) is consistent with La Nina in the Midwest
but not consistent in the Northwest.   Outlook
temperature is not indicated in that the deviation
of daily temperatures is more important than the
seasonal mean temperature.  As of today I have not
changed the computed 70+% chance of US corn yield
being below 150.6BPA.
Note:  Due to major organizational adjustments it
is not clear what my radio broadcast program will
be this season.             – Elwynn—

Iowa State University Extension