Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Paducah Kentucky
707 am CDT Wednesday may 6 2015

issued at 706 am CDT Wednesday may 6 2015

For aviation discussion only.


Short term...(today through Friday night)
issued at 319 am CDT Wednesday may 6 2015

A 500 mb high pressure center over middle Atlantic will continue to ridge
back westward into the Ohio Valley today and much of Thursday. This
should serve to suppress any of the buckled warm/moist advection
flow headed our way from the continuous southwest u... the
southern jet stream is opening up from. Meanwhile...a tropically
influenced low pressure area will begin to circulate onto the
southeast U.S. Coastal area late in the work week. This will
eventually help weaken the high...which may allow some of that
aforementioned moisture plume/embedded ripples work their way into
the western County Warning Area with a slight chance mentionable on Thursday
afternoon...perhaps aided by some PM heating instability. This
activity may be a bit more concentrated by Friday
afternoon...especially over southeast MO into SW a frontal systeminches
closer from the plains.

Long term...(saturday through tuesday)
issued at 319 am CDT Wednesday may 6 2015

The long term period will be dominated by a slow-moving upper level
low that will eject northeast from Arizona across the plains to the
Great Lakes. A few shortwaves will rotate east/northeast beneath the
main upper level feature. These impulses will bring periods of
showers and thunderstorms. On Tuesday...dry air and high pressure
will move east into the lower Ohio Valley as the upper trough
progresses east of our longitude.

As far as the daily details...

On Saturday...a weak cold front will sag south across Missouri and
Illinois. By Saturday night...the GFS/GFS ensemble mean position the
front between the Interstate 70 and 64 corridors. Recent runs of the
European model (ecmwf) consistently keep the front further north in Missouri and
Illinois. At upper levels...a lead 500 mb shortwave will eject
northeast across the middle Mississippi Valley on Saturday. Showers and
thunderstorms are likely in southeast Missouri...closer to the path of the
shortwave. Probability of precipitation will be in the chance category further east.

On Sunday and Sunday night...low level convergence will diminish as
the front moves back north as a warm front. However...deep moisture
will be in place...with precipitation water values over 1.5 inches /00z
GFS/. Another impulse may rotate northeast toward the Mississippi
Valley...which would likely generate some convection in the moist
air mass. Probability of precipitation will be near 50 percent in most areas.

On Monday and Monday night...a trailing cold front will move slowly
east across the middle Mississippi and lower Ohio valleys. This front
will be associated with the primary shortwave trough or upper low.
The highest forecast probability of precipitation will be during this time period...mainly
in the likely category. This is also when the potential for strong
to severe convection appears highest. Middle level wind fields will be
rather weak over the weekend...but should increase with the arrival
of the primary shortwave trough Monday.

On Tuesday...the upper trough will be east of our region...and
surface high pressure will build east from the plains. Clearing
skies are expected...along with lower humidity.

High temperatures will be in the 80s over the weekend...even though
abundant cloudiness is expected. 850 mb temperatures will be pushing 18
celsius /00z European model (ecmwf)/ and each day will start off in the middle 60s.
Highs should be closer to 80 on Monday given the potential for
numerous showers and storms. Tuesday will be cooler behind the
front...with highs in the lower to middle 70s.


issued at 707 am CDT Wednesday may 6 2015

Forecast for the next 24 hours looks to be fairly benign/VFR. High
cumulus bases will again develop in the 050-070 feet above ground level range this
afternoon. Winds will be generally south at or below 10-12kts. Winds
should subside after 00z- 01z.


Pah watches/warnings/advisories...



National Weather Service Glossary of Abbreviations