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fxus63 kpah 181018 
afdpah

Area forecast discussion
National Weather Service Paducah Kentucky
518 am CDT Fri Oct 18 2019

Update...
issued at 518 am CDT Fri Oct 18 2019

Aviation update.

&&

Short term...(today through Saturday night)
issued at 241 am CDT Fri Oct 18 2019

Surface high pressure ridge axis was just east of the County warning forecast area early
this morning, with light winds across the area, and clear skies.
Return flow has set up to our west across the southern and Central
Plains. Water vapor imagery and upper air data shows a ridge across
the nation's mid section, with a low over the Texas Gulf Coast region.

Quiet weather will continue today through tonight, as the surface
high slowly moves east away from the area, while the upper ridge
axis progresses east as well ahead of S/WV energy moving across The
Rockies toward the plains. We will see slightly warmer temperatures
today, upper 60s to 70 degrees. Lows tonight should be in the lower
to mid 40s.

We were finally able to remove pops Saturday and Saturday night, due
to S/WV energy to our west, staying north and west of the area,
while the system over the Gulf pushes east and prevents any moisture
transport of significance into our area. All of the models are in
line with this projection. We cannot rule out an isolated shower or
sprinkles entirely (say across semo, and the Kentucky pennyrile). But for
now, confidence is too low to include any pops. We should see lower
70s for highs Saturday. We raised lows a category for Saturday
night, given the chance of additional cloud cover and a light wind.

Long term...(sunday through thursday)
issued at 241 am CDT Fri Oct 18 2019

We continue to monitor the potential for heavy rain and
strong/severe thunderstorms with a system moving through Sunday
night through Monday.

In the mid/upper levels, a deep trough will get carved out over the
plains on Sunday and progress eastward into our area on Monday. A
closed 500mb low will form and move into Minnesota on Monday. At the
surface, low pressure will develop near the South Dakota/Nebraska
border on Sunday and move northeast into the upper Midwest on
Monday. A strong cold front will push into our region, with a large
swath of rain and embedded thunderstorms accompanying it.

Model guidance continues to come into a bit better agreement on
frontal timing. Overall, there has been a trend for a slightly
faster arrival. The GFS/European model (ecmwf) operational and ensemble mean
solutions favor the cold front moving through the area Monday
morning and afternoon, with it likely being east of our cwa by 00z
Tuesday.

There remains some potential for severe thunderstorms, given MUCAPE
values forecast to be up around 500 j/kg. A strong low/mid level jet
(850mb winds of 50+ kts and 500mb winds of 85+ kts) is expected to
develop over/nearby our area as the cold front moves through. Strong
forcing will be in play, combined with the impressive wind fields,
and good low level moisture (low to mid 60s dew points). So it won't
take much instability for at least a few strong storms to develop,
as a potential qlcs may materialize.

A deep fetch of moisture from the Gulf will also lead to a heavy
rain and localized flooding threat. Precipitable water values are
forecast to reach around 1.75", which is around the 99th percentile
for October. However, given the progressive nature of this system,
it may tend to limit the overall heavy rain threat. We continue to
hedge towards wpc for quantitative precipitation forecast amounts, which gives an average range of
0.75-1.75" across our area.

Behind the Monday system, surface high pressure builds eastward from
the Southern Plains, providing a nice stretch of weather for Tuesday
through at least Wednesday night. There is some disagreement in
model guidance as we head into Thursday. The 00z GFS and a few of
the GFS ensemble members have another cold front moving into our
area as a trough digs across the center of the country. However, the
consensus holds this potential system off until Thursday night or
Friday, just beyond this 7 day forecast. For now, went with a dry
forecast on Thursday.

Temperatures will start out above normal in the 70s on Sunday, and
cool to slightly below normal in the 60s Tuesday through Thursday.

&&

Aviation...
issued at 518 am CDT Fri Oct 18 2019

Shallow fog, with vv's have developed along and near bodies of
water early this morning. Some impact through daybreak is
anticipated at kpah and kcgi. The fog will burn off quickly
after 12-13z. Rest of today and tonight, VFR conditions with light
east/southeast winds.

&&

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

$$

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