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fxus63 kpah 180424 

Area forecast discussion
National Weather Service Paducah Kentucky
1124 PM CDT Tue Sep 17 2019

issued at 1121 PM CDT Tue Sep 17 2019

For aviation section only.


Short term...(tonight through Wednesday night)
issued at 252 PM CDT Tue Sep 17 2019

An axis of higher dewpoints extends over southeast Missouri into
far southwest Kentucky this afternoon, leading to surface cape
values of 2500-3000 j/kg. A few very isolated showers have popped
up over this area, and may continue through the late afternoon
hours before dissipating with sunset. Otherwise, it is another hot
day with 2pm temps in the low to mid 90s across the southwest half
of the region. Slightly cooler air has filtered into our
northeast, but it is still above normal for mid September.

A 500mb ridge will maintain a firm grip on our region through the
short term. With this feature in place, any convection will be
hard to come by. However, a few of the 12z href members continue
to hint at isolated showers developing over portions of southeast
Missouri tomorrow afternoon, similar to what is occurring today.
For now will continue to ride with a silent pop though.

Heat index values will once again approach 100 in portions of
southeast Missouri, far southern Illinois, and far west Kentucky
on Wednesday afternoon.

Long term...(thursday through tuesday)
issued at 252 PM CDT Tue Sep 17 2019

The overall pattern in the long term will gradually become more
active as the persistent east U.S. Ridge weakens due to a trof over
the Atlantic, moving away from the coast, and a more progressive
flow out west as one trof moves from The Rockies toward the Great
Lakes, and a second digs in over the southwest U.S. The 00z ecens,
and 00z/06z gefs offered the best model blend approach to the
forecast Saturday and beyond. For Thursday through Friday, we used a
50/50 blend of the deterministic GFS/European model (ecmwf) and their ensemble mean
solutions from the same runs, as well as the 12z GFS. For Thursday,
think the GFS is overdone with quantitative precipitation forecast (typical). There really isn't
support for anything more than say a 10 percent pop. Will leave it
dry for now. The NAM and European model (ecmwf) show none. Friday is a tough call. The
European model (ecmwf) continues to be bullish on scattered convection over the west
1/2 of the area. The GFS and CMC confine it more into semo, and the
NAM shows almost nothing. Will keep pops low and focused mainly on
semo, as remnant energy from ts Imelda does become a limited factor,
heading NE toward the area.

Most of the convective chances this weekend will be over the northwest 1/2
of the area (semo, into southern IL, maybe swin). Better chances are
Sunday. There may be little to no activity anywhere Saturday. The
chances will come with a front forecast to move into the area
late Sunday or Monday. The Ops models are a bit faster, ensemble
mean solutions slower. Chances should diminish or end sometime
Monday into Monday night as high pressure builds in over the area.
Confidence in the Sunday to Monday forecast is low. We also
backed way down on the nbm quantitative precipitation forecast due to the degree of uncertainty.
Wpc appeared much better as a starting point.

Temps will start out well above normal Thursday, then back down
some, but remain above normal for the rest of the long term.
Ensemble mean MOS was primarily used for temps Saturday and beyond.


issued at 1121 PM CDT Tue Sep 17 2019

Generally clear skies with light ENE daytime winds. Shallow fog
may develop in similar areas to recent early mornings,
particularly portions of se MO/SW Illinois.


Pah watches/warnings/advisories...


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