Area Forecast Discussion
Issued by NWS Paducah, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
000
FXUS63 KPAH 301731
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1231 PM CDT SAT JUL 30 2016

.UPDATE...
Issued at 1231 PM CDT Sat Jul 30 2016

Aviation update.

&&

.SHORT TERM...(Today through Monday night)
Issued at 147 AM CDT Sat Jul 30 2016

The NAM and the HRRR short term modeling of the southern IL
convection sweep it eastward, with the HRRR diminishing, and the
NAM maintaining it, as it moves into SWIN later this morning. Both
models suggest additional activity develops as well, mainly after
sunrise. Neither can resolutely pick up current conditions, with
both showing weaknesses in spatial organization of the mesoscale
happenings. Anticipate the general theme of scattered convective
elements in the high theta environ to continue, however, as we
head thru the daytime hours, providing additional support to high
CAPE airmass, as weak perturbations embedded in the cyclonic flow
aloft further agitate/enhance updraft potential Today.

A relative pause may then occur tonight, although the transition
to warm sectoring may still yield isolated cells here and there
even thru the overnight hours, in the basically unchanged airmass.

Ridging west, and troffing east, in the upper flow will drive a
nwly flow aloft by Sunday, with additional perturbation energy
diving southeastward and overtop the PAH FA. This will markedly
spike Pops by Monday, esp across the northern 2/3 of the FA, where
the bulk vort max energy advects. Therefore anticipate an
increasingly active convective environ Sunday into Monday, with
locally heavy rainfall in the high PW environ continuing to be the
primary hazard.

.LONG TERM...(Tuesday through Friday)
Issued at 338 AM CDT Sat Jul 30 2016

The long term pattern will consist of 500 mb ridging over the Plains
and weak troughing along the Eastern seaboard. This has been a very
common pattern for most of the summer, and therefore the weather
pattern will be very familiar. Heat indices will be in the triple
digits each afternoon, and thunderstorm chances will exist almost
every day.

Thunderstorm chances will be relatively high on Tuesday, when the
500 mb ridge will not yet be firmly established. There may also be
some low-level convergence on the back side of the surface high,
near a warm front.

Thunderstorm chances will be on the decrease Tuesday night through
Thursday as the center of the 500 mb moves closer. As we have seen
this summer, thunderstorm clusters can form very close to the ridge
axis. Therefore, slight chance pops will be included even on
Thursday. Any storms should be mostly diurnally driven under the
ridge.

The potential for storms on Tuesday should keep highs mainly around
90. There will be a slight increase in temps and heat indices
Wednesday and Thursday. The 00z ecmwf and gfs mos highs are in the
mid 90s both days at many locations, and 850 and 2 meter temps
support these mos highs. However, the official guidance blend keeps
highs mainly in the lower 90s.

&&

.AVIATION...
Issued at 1231 PM CDT Sat Jul 30 2016

Will use a persistence forecast. Monitor and include convection
when appropriate, as confidence too low right now to pin point.
Light winds overall. Fog potential again later tonight. Variable
clouds, mainly VFR, possibly MVFR bases at times. Low confidence
for low cigs late tonight.

&&

.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&

$$



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