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Area forecast discussion 
National Weather Service Paducah Kentucky
1251 PM CDT Monday Jul 6 2015

Update...
issued at 1251 PM CDT Monday Jul 6 2015

Updated aviation discussion for 18z tafs.

&&

Short term...(today through Wednesday night)
issued at 343 am CDT Monday Jul 6 2015

After some patchy early morning fog...today looks like another
partly sunny and very warm day. Unlike Sunday...there will be some
wind...averaging around 10 miles per hour from the southwest. The southwest
winds will bring somewhat warmer and more humid air. Guidance has
been just a bit too warm lately...so forecast high temperatures will be
kept in the upper 80s for today. There is a small chance of
showers and storms...mainly this afternoon. The hrrr in particular
brings some convection into southeast Missouri and southern Illinois late
today. This appears to be related to a weak 500 mb shortwave that
will cross Missouri and Arkansas late today. The activity should
not reach SW Indiana or the pennyrile of west Kentucky until tonight.

During the night tonight...most of the mesocale guidance
/especially the nmm-WRF and arw/ develops a considerable amount
of precipitation over the lower Ohio Valley and southeast Missouri. The
00z NAM is a notable exception. This activity will be ahead of a
cold front that will move southeast across central Missouri by
12z. Given that the less reliable mesoscale models are leading the
way on this precipitation...forecast probability of precipitation will only be in the chance
category.

On Tuesday...the cold front will move southeast into southeast Missouri
and southern Illinois. The front will then stall along or just north of
a kevv/kcgi line Tuesday night before lifting back north on
Wednesday. Compared to model runs the previous two days...the
models have trended a little further north with the frontal
location Tuesday night and Wednesday. The exception is the
GFS...which has been consistent. The models have also trended a
little lower with rainfall amounts. Although heavy rainfall will
be the main hazard...it looks less significant than 24 hours ago.
Likely probability of precipitation will remain confined to areas north of a
kcgi/kpah/Madisonville line...with chance probability of precipitation to the south.

The clouds and precipitation will keep highs generally in the lower to
middle 80s both Tuesday and Wednesday. The NAM is significantly
warmer and drier /and it has been consistent/...but it is also an
outlier. Overnight lows will be around 70.

Long term...(thursday through sunday)
issued at 343 am CDT Monday Jul 6 2015

Increased confidence in the long term as models finally coming into
better agreement on timing and placement of synoptic features and/or
precipitation chances.

The long term period starts off with a quasi-stationary frontal
boundary stalled just to the north of our County Warning Area. The presence of the
boundary coupled with pooled-up moisture and instability will likely
generate showers and thunderstorms across all of the region on
Thursday. Precipitation chances are forecast to diminish from
southwest to northeast Thursday night and Friday as a surface low
lifting northeast out of the plains will lift the boundary to the
north and east.

Beyond this point is where models were previously having difficulty
coming into agreement...ie one was showing 500 mb ridging developing
over the area while the other kept US in zonal flow. Latest runs now
showing 500 mb ridging from Friday night through the end of the period.
The European model (ecmwf) is showing the ridging to be a bit stronger while the GFS
not so much. With better agreement between new model runs...felt
comfortable removing tangible probability of precipitation from Friday night through Sunday.

Due to the 500 mb ridging...temperatures and dewpoints are expected to
be near normal through the period.

&&

Aviation...
issued at 1251 PM CDT Monday Jul 6 2015

Scattered cumulus and some low stratus clouds will affect the taf
sites this afternoon with periods of MVFR ceilings possible at
kcgi/kevv/kowb. Isolated -tsra can't be ruled out at kcgi this
afternoon but threat is too low to include. Overnight middle clouds
lower as cold front approaches from northwest. Timing of potential
rain showers/thunderstorms and rain affecting terminals is not clear so covered with a
prob30 for most likely time periods. MVFR fog is possible with
this activity late tonight into tmrw morning.

&&

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

$$

Update...snow pellets
short term...my
long term...jp
aviation...snow pellets

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