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Area forecast discussion 
National Weather Service Paducah Kentucky
1034 am CDT Tuesday may 26 2015

issued at 1034 am CDT Tuesday may 26 2015

South southwest winds are already gusting this morning...and with
good mixing expected through the afternoon...winds should be
sufficient to support a lake Wind Advisory throughout the forecast

An outflow boundary or dry line boundary is progressing eastward
through the region and runs from near kmvn to kpah at 1530z. This
boundary will most likely mark the back edge of any convective
development today. With considerable cloud cover ahead of it
through our entire area...development may be hindered if not
completely shut down until it passes out of our area. Tried to
re-work hourly pop trends...and keep them below likely levels.


Short term...(today through Thursday night)
issued at 252 am CDT Tuesday may 26 2015

Should be a fairly unsettled day coming up as a negatively tilted
h50 short wave ejects NE across the middle/upper MS valley region and
interacts with leftover surface outflow boundary/trof. One of the
bigger questions lies with left over cloud cover and the amount of
instability that can develop as the day progresses. If decent
heating can take place...should see organized convective bands
develop east of the MS river by early afternoon. Though wind gusts
will be the main storm risk in bowing segments...shear values
suggest an isolated tornado cannot be ruled out.

00z GFS does suggest another short wave may affect portions of the
region later on Wednesday or Wednesday will leave at least chance
probability of precipitation in for a few strong to severe storms in that time frame as
well. Things should settle down more as we head into Thursday time
frame. However...with increasing amounts of sun will come
increasing surface temperatures into the middle/upper 80s.

Long term...(friday through monday)
issued at 252 am CDT Tuesday may 26 2015

High confidence in a warm humid week with at least scattered afternoon
showers. Low confidence in cold front passage late weekend early
next week.

The blended models...ensembles and operational models are weak to
complete flip flopping with the cold front this weekend. Thus the
extended init is slow to show a true wind shift if any at all. In
contrast the latest GFS and European model (ecmwf) are within six hours of each other
concerning the wind shift. Its definitely odd but the European model (ecmwf) brings in
the wind shift a good six hours faster than the GFS...which is
usually the opposite with the European model (ecmwf) being the slower model with
systems typically. The European model (ecmwf) is advertising a frontal passage Sunday while the
GFS is more like Sunday night. At least they both agree the front
will actually come through which has not always been the case the
past few days. Lifted indice's stay negative until late Sunday with convective available potential energy
around convective available potential energy ranging from around 200 j/kg/2 overnight to near 2000
j/kg/2 in the afternoon until Sunday. Thus expect at least daily
chances of convection maybe some breaks overnight. Mostly
unorganized non severe...but cant rule out isolated severe with wind
being the main threat. The best chance of strong or severe will
definitely be with the frontal passage Sunday.

Temperatures and humidity will remain high or above normal until this
weekend when precipitation and cloud cover should lower the apparent
temperature somewhat and of course after the cold front passage we
will fall below normal.


issued at 1205 am CDT Tuesday may 26 2015

Area of showers expected to spread across kcgi/kpah between 8-10z,
and kevv/kowb between 10-12z. VFR ceilings/visibilities will drop to MVFR
with showers. Shower chances will drop off at kcgi/kpah around
15z, and around 17z at kevv/kowb, and conditions will improve to
VFR. Winds will be southeast at 6 to 12 kts overnight, then
increase from the south/southwest after 14z to 10 to 15 kts with
gusts around 20 kts. Precipitation chances after 18z too low to include
in tafs.


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.



short term...GM

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