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Area forecast discussion 
National Weather Service Paducah Kentucky
610 am CDT Monday Apr 27 2015

Short term...(today through Wednesday night)
issued at 300 am CDT Monday Apr 27 2015

A rather quiet short term period expected...but only average
forecast confidence as models still not in the best agreement with
the one system affecting the region.

A potent storm system over the Southern Plains at the time of this
writing will move slowly eastward across the deep south through middle
week. In the process...the northern edge of the precipitation shield
associated with the system will graze/skim the far southern portions
of our County Warning Area on Tuesday...then the far southeast sections Tuesday
night and Wednesday. Models still not in good agreement on quantitative precipitation forecast
coverage with this feature. The latest GFS continues to be the most
aggressive...the Canadian the least aggressive...and the nam12/European model (ecmwf)
somewhere in between. Either way...any areas affected would only
receive light precipitation so no big concerns in that regard.

High pressure at the surface and cloud cover will keep temperatures
below normal through the period.

Long term...(thursday through sunday)
issued at 300 am CDT Monday Apr 27 2015

At the beginning of the extended forecast period, an intense upper
low will develop and slide down from Lake Michigan to the western
sections of the Ohio Valley. This westwardly tilted upper low will
have little surface reflection within the weather forecast office pah forecast area,
with the greatest impact along the eastern Seaboard of the U.S.

A high amplitude high pressure ridge will have greater influence
across the local area through Saturday, but will broaden and Delaware-
amplify over the U.S. As the previously mentioned upper low moves
into the western Atlantic.

Minor impulses generated across the Lee of the Rocky Mountains will
serve to propagate embedded and dampening shortwaves in the broad
ridge from the Central Plains into the middle Mississippi Valley.
These impulses, combined with slow return flow from the Gulf of
Mexico, west of a eastern U.S. High pressure ridge, along the
northwest edge of the middle level reflection of this ridge over the
southeast U.S.

Any instability associated with the interaction of the impulses and
the slow Gulf of Mexico moisture return will limit coverage of any
thunderstorm activity within the weather forecast office pah forecast area boundaries
Sunday into Monday. Given the uncertainty as to the degree of
instability and forcing, am not inclined to forecast much more than
slight chances of showers and thunderstorms for late Sunday into
next Monday.

A gradual warm up should take place through the period, with a
return to at or above normal temperatures by Friday.


issued at 610 am CDT Monday Apr 27 2015

Very minor differences from 06z Monday weather forecast office pah taf forecast
package. For those aviation interests dealing with aerial
photography...etc...added a graduated mention of cirrus cloud deck
from west to east across the weather forecast office pah taf sites. This deck will be
somewhat variable depending on the ejection cloud debris from
shower/thunderstorm complexes associated with a low in the
Southern Plains. Wind forecast remains on target from previous
forecast package.


Pah watches/warnings/advisories...



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