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Area forecast discussion 
National Weather Service Paducah Kentucky
637 am CDT Tuesday Sep 1 2015

issued at 637 am CDT Tuesday Sep 1 2015

The aviation section has been updated for the 12z taf issuance.


Short term...(today through thursday)
issued at 321 am CDT Tuesday Sep 1 2015

Beginning to see some mid-level clouds developing over the
northern half of the region, and the upper low shows up real nice
on water vapor imagery over east, central Indiana. Some patchy fog
has been reported at a few locations, but it has not been terribly
persistent. Will keep a mention of patchy fog over much of the
area for an hour or so after daybreak.

The hrrr indicates that there may be some shower and storm
activity with this cloud development over southern Illinois by
daybreak, but it quickly kills it off by late morning. The nmm and
arw WRF runs develop some convection closer to the upper low
before daybreak and then build it south down the Wabash valley and
then southwest through southern Illinois through the morning. This
seems most plausible, so used it as a guide for pop placement
through the day.

Coverage is not expected to be too great, and it may not happen
at all, so kept pops at slight chances only. If the WRF runs are
right, there won't be much left after 18z, but will keep the
slight chances over southern Illinois and much of southeast
Missouri through the afternoon just to be safe. The remainder of
the short term portion of the forecast is dry, with high pressure
at the surface and aloft through the period.

Looking at temperatures, the GFS and European model (ecmwf)-based MOS guidance
seems too hot for highs today through Thursday, as they have been
for most of this Summer. The previous forecast had this well in
hand, so did not make much change at all. There will be a slight
warming trend through Thursday, but with the surface high centered
right over the area, a major warming trend is not likely.

Long term...(thursday night through monday)
issued at 321 am CDT Tuesday Sep 1 2015

Hot and dry conditions are expected during the long-term period
beneath a large upper-level high. Very little difference in temps or
humidity is expected from day to day. Highs will generally be in the
lower half of the 90s...tho some of the more recent MOS suggests we
may test the mid 90s Friday and Saturday.

Given the easterly low level flow, dew points are not forecast to be
as high as previous heat waves this Summer. Forecast dew points
through the long term will be from 65 to 70, which is rather low
compared to the 75 to 80 degree dew points earlier this Summer. The
ground has become significantly drier since the July flooding
events, which supports a forecast of lower humidity levels. On the
other hand, lower humidity also supports higher temps during the

Will need to keep an eye the the possibility of an easterly wave
moving west into the se U.S. Toward the end of the long term. At
minimum, this wave could help to bring down temps a notch or two,
and could also bring a few showers to portions of the region, esp
wrn Kentucky.


issued at 637 am CDT Tuesday Sep 1 2015

With scattered mid clouds and an occasional breeze, fog
development was limited to MVFR levels only this morning. Will
leave a mention in for an hour at kcgi and kpah. Isolated
thunderstorms may develop southward into the region this morning,
but it will most likely impact southern Illinois this morning
before dissipating this afternoon. Will not mention in any of the
tafs at this time, but will monitor radar trends closely. Went on
the optimistic side with fog forecast for late tonight. Only
mention was MVFR at kcgi.


Pah watches/warnings/advisories...


short term...drs
long term...GM

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