Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 100837
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
337 AM CDT Thu Apr 10 2014
.SHORT TERM...(Today through Saturday night)
Issued at 155 AM CDT THU APR 10 2014
As a weather front takes shape and approaches from our northwest,
the pressure gradient tightens up and we`ll become breezy and
gusty this afternoon. The front makes passage overnight, and a
chance of a shower/storm will accompany its passage, a slow move
thru and east of us that means pops for tonight-Friday.
After the fropa, the weekend returns to mild/dry. A warming trend
noted today is dealt a temporary cool off tomorrow in the
immediate post frontal environs, then warming again over the
.LONG TERM...(Sunday through Wednesday)
Issued at 335 AM CDT THU APR 10 2014
A strong storm system remains the primary forecast concern in the
long term. The models remain in very good agreement on a moderate to
heavy rainfall event Sunday night into Monday. There are still
differences concerning the track and timing of the system...which
will determine the potential for deep convection.
As far as the daily details...
Sunday will be a breezy...warm...and mainly dry day. A strong cap
between 700 and 800 mb will inhibit convection most of the day. The
cap will weaken late in the day as a strong 500 mb shortwave emerges
out of the southern Plains. Will maintain chance pops...mainly north
and west of the Ohio River...to account for the possibility of late
day showers and storms. Strong southerly low level flow will raise
temps well into the 70s. The greatest amount of sunshine and warmest
temps should be over western KY.
On Sunday night...widespread showers and storms will overspread the
region as the 500 mb shortwave ejects northeast from Texas. The
surface cold front will move east/southeast across Missouri and
Illinois. Plenty of deep moisture will be in place...with precip
water values near 1.5 inches ahead of the front. Boundary layer dew
points are forecast to reach the lower 60s. Strong forcing colocated
with deep moisture will yield some locally heavy rainfall amounts.
The progressive nature of the system will limit the duration of the
rainfall event and its associated flooding potential...if any.
As far as convective potential...there are still too many model
differences concerning the finer details to accurately assess this
potential. The 00z gfs ensemble mean is notably faster than the 00z
operational runs of the gfs and ecmwf. The gfs ensemble mean is also
weaker and further east with the 850 mb jet axis. The main limiting
factor for severe convection still appears to be weak instability.
Both the 00z gfs/ecmwf indicate capes below 1000 j/kg through the
event. Of some concern is that both models increase the 850 mb jet
to 60 knots over our region by late Sunday night. The presence of
such strong low level shear in a moist and marginally unstable
environment would warrant close attention if it occurs.
The strong cold front will move east across our region by 18z
Monday. Precip will taper to showers or end on Monday. Strong gusty
northwest winds and overcast skies will bring noticeably cooler
The sharply cooler temps will linger through Tuesday night...with
some frost possible both Monday and Tuesday nights. The timing of
the surface high pressure varies between models. If the surface
ridge axis passes overhead during the late night/early morning
hours...frost potential would be realized.
A slow moderation in temps is likely Wednesday and Thursday as the
high moves to the east. The ecmwf is slower with the warmup due to
its slower eastward progression of the upper trough. Dry conditions
are expected during the middle of the week.
Issued at 155 AM CDT THU APR 10 2014
South winds will start to increase through the morning hours. Winds
aloft support gusts near 30 mph by this afternoon. These winds
will be ahead of a cold front that will bring some high clouds to
the region. The front ultimately will bring some lower level
clouds (still VFR) and possible precipitation by late evening-overnight,
mainly for KEVV/KOWB.