Area Forecast Discussion
Issued by NWS Paducah, KY

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FXUS63 KPAH 251853

153 PM CDT Fri Jul 25 2014

Issued at 153 PM CDT FRI JUL 25 2014

Decaying MCS northwest of STL area continue to present an
expansive shield of anvil precipitation across Southwest Illinois.
Although there is a question whether there will be enough
precipitation falling from the anvil precipitation to warrant QPF
beyond a trace, decided to add a mention of light showers along
the I-64 corridor in Southeast IL and Southwest Indiaan through
late afternoon.

The greater impact this afternoon will be the reduction in
temperatures due to the cooling effect of the opaque cirrus deck.
Adjusted hourly temperatures under the cloud shield this
afternoon, effectively dropping maximum temperatures by up to 3
degrees from originally forecast highs.


.SHORT TERM...(Today through Sunday night)
Issued at 155 AM CDT FRI JUL 25 2014

High pressure will move east today, with NW flow aloft in place
NE of ridge center over the southern Plains and Rockies.
Temperatures should be slightly warmer with return flow just
getting going. H7 heights build through tonight and Saturday. This
should keep convective chances out of the picture, until perhaps
Saturday afternoon across the northern 1/3 of the area (slight
chance PoPs). Chances will increase NNE 1/3 of the area Saturday night
as perturbations move ESE in the mid trop flow and interact with
more than adequate instability. Moisture is the main question
mark, even into Sunday. Convection appears likely, but coverage,
southward extent and magnitude are still question marks. Thus no
more than chance PoPs north for now. Models show best moisture
departing the KEVV tri-state area Sunday morning with only marginal
moisture the rest of the day. The frontal aspect and degree of
instability warrant PoPs later Sunday, but coverage is uncertain at
this point. Chances linger in the evening over the SE 1/3 of the
area, then dry from midnight on Sunday night. Should be hot Saturday
and Sunday. Heat indices around 100 west 1/2 of the area Saturday
and most of the area Sunday. Any of the convection could be strong
to perhaps briefly severe, primarily across the NRN 1/3 of the area.

.LONG TERM...(Monday through Friday)
Issued at 1254 PM CDT FRI JUL 25 2014

It is amazing to look at the pattern transition for next week,
considering the late July-early August time frame. The models
still develop the broad upper level troffing over the eastern
U.S., with the Low nearly cut off as it centers somewhere in the
vicinity of the mid Mississippi valley by next weekend.

The end result is going to be an abundance of pleasant weather
conditions with high confidence much below normal temps/pcpn for
the week long period.

The first half of the workweek will see surface High pressure
coming in from the north and all but keeping some flow of
northerlies reinforcing the atmosphere. This will help skies to
stay moclear with low humidity highs in the upper 70s and lower
80s and crisp lows in the upper 50s to lower 60s.

By the middle to latter part of the workweek, the surface High
shifts eastward, and we`re in a somewhat muddier easterly or
southerly lower tropospheric flow. This still means relatively low
dew points, with a move from the 50s early in the week to no more
than the lower 60s by the weeks end. But it could be just enough
return moisture to allow for a spotty shower or two to develop by
Friday, as the upper Low center drops down and introduces itself
into our FA/vicinity. Slightly moderated Highs in the lower to
middle 80s and lows in the lower 60s will remain comfortably
below climo norms.


Issued at 124 om CDT FRI JUL 25 2014

To users of the WFO PAH TAF`s, sent incorrect forecasts earlier,
but reissued corrected TAFs around 1817z.

Cirrus blowoff from convective activity upstream over West Central
Illinois and East Central Missouri will dominate VFR cloud cover
forecast for the WFO PAH TAF sites this afternoon, thinning out
this evening over KCGI/PAH. A middle level deck will likely remain
dominant over KEVV/KOWB during the evening.

Otherwise, most of the convection should remain just north of the
KEVV/KOWB TAF sites before 18z Saturday, so only mentioned a
vicinity chance for showers at this time. Most cloud cover should
remain at or above the forecast limits of the KCGI/KPAH TAF sites,
so kept unrestriced ceilings in place at this time.




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