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Area forecast discussion 
National Weather Service Paducah Kentucky
650 PM CDT Wednesday may 27 2015

Short term...(this evening through Friday night)
issued at 225 PM CDT Wednesday may 27 2015

Mesoscale environment is more favorable for late day convection to our
south and east...where ongoing elements are advecting. Visible
shots/surface plot show dry air mixing into the already worked
over airmass in its wake...expanding across our western counties
and further upstream (northward/westward). 88d notes some
development just now getting going on the
differential heating boundary across northern Arkansas...and may
continue to impact our southern counties with a pop into at least
the early evening hours.

Beyond the near term...we see an open/wet southwesterly flow aloft through the
entirety of the short term forecast. As a northern stream long
wave trough/speed maximum barrels its way across the interior Canadian
provinces en Route to the Great will drive a cold front
gradually closer to US with time. This front will serve to better
focus moisture/heat energy along/ahead of it as it moves into the
middle Mississippi Valley region toward the end of the period. The
result...a slow/but sure steadily increasing pop with time as we
move through the duration of the short term forecast period.

Temperatures will range l-m80s for highs and l-mid60s for lows as the
atmos soups up to a more muggy Summer like feel.

Long term...(saturday through wednesday)
issued at 225 PM CDT Wednesday may 27 2015

We continue to watch the approach of a cold front advancing from the
northwest on Saturday. It continues to look rather wet as the front
ends up crosses the County Warning Area during the day on Saturday. Tempted to go
higher than likely probability of precipitation but may wait a bit longer to raise them that
high. The cold front will settle south of the area during the
evening and overnight hours on Saturday night.

However...a fairly potent upper level trough will move southeast
toward the region Saturday night and into Sunday. This will allow
for continued thunderstorm development through the night and into
the day on Sunday. Models had been having a hard time deciphering
how to handle the pattern beyond Saturday. However...the signal has
now become rather good that the weekend will be pretty wet.

Rainfall amounts look to be pretty decent over the weekend given the
fairly high precipitable water values and strong SW flow aloft. However...nothing
right now points to any real flooding concerns other than localized
problems. Will continue to monitor to see if the threat for more
widespread flooding grows.

Models continue to be very erratic when it comes to the forecast for
early next week. Tehre have been a myraid of different solutions the
past few days...including a cut off low developing in our vicinity.
The 12z GFS/European model (ecmwf) continue to show this possibility. would
be prudent to keep at least some type of chance going with the
amount of uncertainity.

We should see a pretty good drop in temperatures from Saturday to 850 mb fall into the low teens over much of the area by
late Sunday into Monday. Depending on how the upper pattern
evolves...temperatures will be right around normal (low 80s) for the
early part of next week.


issued at 649 PM CDT Wednesday may 27 2015

Low confidence with this 00z Thursday weather forecast office pah taf package. With
the surface front just to the north of the taf sites...the passage
of weak perturbations at middle-levels may support more or less
persistent MVFR ceilings and visibilities south of the front
overnight through at least 15z Thursday. Leaned closer to the more
pessimistic NAM-WRF guidance with this issuance for ceilings. May
have to address this during any updates that may be required in
the 01z-02z time frame tonight.


Pah watches/warnings/advisories...



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