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fxus63 kpah 111719 
afdpah

Area forecast discussion
National Weather Service Paducah Kentucky
1119 am CST Wed Dec 11 2019

Update...
issued at 1120 am CST Wed Dec 11 2019

Updated aviation discussion for 18z tafs.

&&

Short term...(today through Friday night)
issued at 355 am CST Wed Dec 11 2019

Weak surface high pressure will slide across the middle
Mississippi and lower Ohio River valleys today, moving well east
of our region tonight. Clear skies are expected today into this
evening, with an increase in clouds beginning from the northwest
late tonight and continuing into Thursday. South to southwest
winds will help temperatures moderate today into Thursday. Highs
today will climb into the lower to middle 40s, with seasonal
temperatures by Thursday with readings in the upper 40s to around
50 degrees.

By Thursday night, a surface low will be moving along the Gulf
Coast as a mid/upper level trof approaches the pah forecast area
from the west. The European model (ecmwf) takes the surface low over the Florida
Panhandle by 18z Friday. Moisture will push north of this low,
and this brings light rain into southeast portions of the region
by Friday morning, spreading chances across west Kentucky and
southwest Indiana through the day Friday. Models take the low up
the Atlantic coast Friday night, and this will spread rain chances
across our entire area, with the best chances across our eastern
half of counties.

Temperatures late Thursday night (in the lower to middle 30s) and
late Friday night (middle 30s to around 40 degrees) may give US
the potential for a little mix of snow with the rain, but these
chances will be very brief and result in no impacts.

Long term...(saturday through tuesday)
issued at 355 am CST Wed Dec 11 2019

A large portion of the long term has fairly low confidence. A rather
potent system is expected to develop as a mid/upper level trof
translates east (then northeast) from the southern rockies Sunday
into the plains and MS River Valley early next week.

Saturday will feature a kind of "in-between" day as low pressure
system departs toward the northeast U.S., And Canadian high pressure
presses southeast into the northern plains. A weak mid level short
wave is expected to scoot through the lower Ohio River valley during
the day, but seems rather moisture-starved at this point and should
not provide much of an impact to our region. May not be much in the
way of sunshine either though, esp east of the MS river, with temps
in the 40s to near 50.

Though the aformentioned surface high will push south into the
Midwest on Sunday, isentropic lift ahead of the trof over the
southern rockies may be able to generate some light precipitation
along and to the north of a west-east oriented sfc boundary located
from the western Gulf Coast states NE into the lower Tennessee River valley
(mainly later in the day). Precip chances will then increase Sunday
night into Monday as a surface low develops on the frontal boundary
and begins to strengthen and head northeast.

It seems as though enough cold air will be in place on Sunday into
Sunday night for any light precipitation to fall in the form of snow
or a rain/snow mix over a good portion of the forecast area.
Thereafter, numerical models fan out with their solutions on where
the sfc low will track, and where an eventual significant quantitative precipitation forecast
amounts, precip types, etc. Will end up as well. Thus, at this
point, think it is best on our end to just message the fact that
this seems to be a system that bears monitoring during the next
several days. Forecast confidence this far out is extremely low. As
an example, the 00z GFS MOS paints a Max temp of 57 at pah on
Monday, while the European model (ecmwf) MOS suggests a high of 38!! it will just
take some more time to get a better handle on this one.

&&

Aviation...
issued at 1120 am CST Wed Dec 11 2019

VFR conditions throughout this forecast period. SW winds around
8-10 kts this afternoon will become light overnight. South winds
will generally be aob 10 kts tomorrow, but there may be some gusts
up near 20 kts to contend with by late morning/afternoon in
northwest portions of the area. Time heights indicate an abundance
of high cloud will spread across the region tomorrow.

&&

Pah watches/warnings/advisories...
Illinois...none.
MO...none.
In...none.
Kentucky...none.
&&

$$

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