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Area forecast discussion 
National Weather Service Paducah Kentucky
1215 PM CDT sun may 24 2015

updated aviation section for 18z taf issuance


Short term...(today through Tuesday night)
issued at 227 am CDT sun may 24 2015

Large upper low over The Rockies at 06z with a prominent ridge
axis at 500 mb from the upper Midwest to southeast U.S. A shortwave will evolve
and head NE from the Southern Plains to Mississippi Valley region
later today through tonight. This feature will result in slowly
increasing chances of convection today through tonight with
highest probability of precipitation west...lower east given the NE trajectory to
convection. Coordinate with Meg and for now...will hold on any watch
headlines for flooding. This may need a revisit on the day shift
should there be an uptick in guidance. For now we are just below
concerning levels. Should be a decrease in activity Memorial Day
especially afternoon through early evening...followed by increasing
chances again from SW to NE Monday night through Tuesday as
another shortwave ejects NE from the Southern Plains to the Mississippi
Valley region. All of this action driven by middle level energy...
without a surface/low tropopause boundary to focus convection. This will be
offset by persistent low tropopause moist transport via a decent low
level jet. Again will certainly have to monitor the heavy rain
potential. Temperatures will be a blend of existing numbers and the
latest MOS output.

Long term...(wednesday through saturday)
issued at 227 am CDT sun may 24 2015

High confidence there will be at least daily scattered
thunderstorms. Low confidence in timing outside of maximum heating for
the extended.

We will be warm sectored for the extended with surface based and
elevated instability. Lifted indice's remain negative with cape values ranging
from 500 to near 2k j/kg/2 throughout the week. Precipitable water range from 1 to
near 2 inches with k indices lowest middle 20s at times but most times
above 30c. There does not appear to be an organized severe threat
but some storms could be strong no doubt. The wind fields are not
particularly favorable for a severe threat but the instability could
yield a warning or two. The main threat will be localized heavy rain
and lightning of course. A collapse of a storm could yield a wind
threat...again isolated if at all. By the weekend the faster GFS
tries to bring in a cold front as early as contrast
the European model (ecmwf) holds it off until Saturday night at the earliest. Thats
not too bad of a discrepancy that far out. Otherwise warm and humid
near seasonal type conditions. With relief in sight next weekend.


issued at 1214 PM CDT sun may 24 2015

Areas of cumulus clouds will continue to spread and develop
northward across the taf sites this afternoon. Ceilings will be
VFR...generally around 5k feet above ground level. Winds will remain gusty from
the south...with gusts to 20 knots fairly common.

An area of thunderstorms will move northeast across the taf sites
tonight. Based on the latest mesoscale model guidance...the
leading edge of storms should reach the kcgi/kpah areas in the 02z
to 06z time frame. Winds may be strong and gusty on the leading
edge of storms. The storms will then cross the kevv/kowb areas in
the 05z to 10z time frame. Some brief periods of IFR are possible
in storms...but not of sufficient duration to include in tafs.

Following the storms...several hours of MVFR conditions are likely
in showers and fog late at night into the early morning. VFR
conditions should return by middle morning Monday.


Pah watches/warnings/advisories...
Illinois...Lake Wind Advisory until 7 PM CDT this evening for ilz075>078-

MO...lake Wind Advisory until 7 PM CDT this evening for moz076-086-

In...lake Wind Advisory until 7 PM CDT this evening for inz081-082-

Kentucky...Lake Wind Advisory until 7 PM CDT this evening for kyz001>022.



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