Area Forecast Discussion
Issued by NWS Paducah, KY

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KPAH 192348

Area Forecast Discussion
National Weather Service Paducah KY
648 PM CDT Fri May 19 2017

Issued at 639 PM CDT Fri May 19 2017

The AVIATION section has been updated for the 00Z TAF issuance.


.SHORT TERM...(Tonight through Sunday night)
Issued at 323 PM CDT Fri May 19 2017

Scattered showers and storms have built northward into west
Kentucky in the last few hours, but all indications are that this
activity will move east and dissipate by sunset, leaving the
entire area dry for most of the evening. In the meantime, we
cannot rule out a stray strong to severe storm, but given the
number of updrafts competing for the available instability and
relatively weak wind fields over the region, organized severe
weather is not expected.

The most recent HRRR output still tries to bring an MCS into at
least southeast Missouri and southern Illinois after 09Z and into
Saturday morning. It appears that the severe potential with this
system will be to our north. With south southwesterly flow through
the column, any significant winds would be associated with
northwest to southeast oriented portions of the line. However,
heavy rainfall will be a concern, especially where the leading line
orients itself parallel to the upper flow.

The models are in reasonably good agreement in dragging the cold
front through our region late Saturday night into Sunday morning.
The convective potential should drop off quickly with the frontal
passage, but we maintain small PoPs through the day Sunday. After
the MCS tonight into Saturday morning, the convective evolution is
unclear. The primary upper-level system will be well north of the
area and we will not have the synoptic cold front in play yet.
Best bet is that we will see scattered development through the
day, especially near any outflow boundaries that remain in play.

Not terribly concerned with severe weather, but given the
potential surface airmass that may develop, especially south of
any outflows, a stray strong to severe storm cannot be ruled out.
Once again, with anomalously high moisture content, locally heavy
rainfall will be the biggest concern. At this time, it is not
obvious which areas may be hardest hit with multiple rounds of
heavy rain tonight through Saturday night so will not be issuing a
Flash Flood Watch.

Still looking much more pleasant behind the front Sunday and
Sunday night with temperatures a bit below normal on Sunday.

.LONG TERM...(Monday through Friday)
Issued at 323 PM CDT Fri May 19 2017

We will have sfc high pressure in our vicinity on Monday but that
system will shift east through the day. Another frontal boundary
will be incoming from the west. Various models as well as the GFS
ensembles seem to have a pretty decent handle on the timing, and
this was the case yesterday as well. We should see dry weather
through the evening hours on Monday, but after midnight Monday night
and into Tuesday, precipitation chances increase. How quickly the
front makes it through Tuesday into Tuesday evening is still a bit
in question.

However, there will be a break in the action after the frontal
passage Tuesday evening or late Tuesday night. The upper level
trough/low will move across the area on Wednesday. This will mean
more clouds, more chances for showers and a downright cool day with
highs only in the 60s. Models have their differences on how quickly
this upper system departs on Wednesday night. May have to linger
some POPs in that period...higher POPs east. We could have a chance
to see lows in the upper 40s in some areas Wednesday night.

We will see improving conditions on Thursday, as well as an increase
in our temperatures and more sunshine as sfc high pressure builds
back into the region. The upper flow transitions to a more
flat/zonal flow by Friday with no large signals for any major
chances for rain.


Issued at 639 PM CDT Fri May 19 2017

Medium confidence in the forecast with much of dependent on
convection movement and/or development. The rest of the evening
should be dry for most of the area. Scattered storms moving north
out of AR will stay far west of KCGI toward the Ozark foothills
and eventually dissipate through the evening. TS chances increase
overnight into Saturday morning. It appears that we will most
likely see an MCS move northeast through all or a portion of the
area 09Z-15Z, but there could be development ahead of it as well,
beginning as early as 03Z. Emphasized the early morning MCS
potential with a wind shift and VCTS at all sites except KOWB.
Kept it VFR for now, but IFR or lower conditions will be possible
if the MCS develops. The forecast beyond 18Z is greatly dependent
on morning convection. Morning convection could work over the
atmosphere precluding the development of afternoon storms. Have
included PROB30 groups at all sites for the development of
convection during the afternoon given the uncertainty of the MCS.




AVIATION...ML is the U.S. government's official web portal to all federal, state and local government web resources and services.