Area Forecast Discussion
Issued by NWS Paducah, KY

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FXUS63 KPAH 231202

702 AM CDT Wed Apr 23 2014

Issued at 702 AM CDT WED APR 23 2014

Updated for aviation forecast discussion.


.DISCUSSION... /ISSUED 218 AM CDT Wed Apr 23 2014/

SHORT TERM...(Today through Friday night)
Issued at 218 AM CDT WED APR 23 2014

Surface high Pressure ridging south into the FA will maintain dry
conditions into Thursday before the ridge moves east and winds
become southerly and advect moisture into the FA ahead of an
approaching cold front.

The latest GFS keeps slightly drier air in the FA longer than the
previous run but then becomes nearly identical with the previous run
in the eastward progression of precip thereafter/by Thursday evening
with the 500mb trough axis to about Dexter MO 00Z Friday. By 06Z
Friday both it and the weak surface cold front will be east of the
FA. The 00Z ECMWF remains about 3 to 4 hours slower than the GFS and
NAM and will lean toward the faster solution which also lines up
with previous forecasts.

QPF amounts still appear fairly modest with averages of 1/3 to 1/2
inch forecast. The greater amounts are likely across mainly the
northern part of the FA...closer to better upper level dynamics.  In
addition, instability will be fairly decent going into Thursday
evening when the system moves across the FA and for now SPC has a
Slight Risk immediately south of the western half of our FA.

Surface High Pressure will be building across the area late Thursday
night and Friday in the wake of the weak cold front. Winds will
quickly back to the southwest Friday as the highest surface pressure
passes to our south. As a result...little change is expected in
temps Friday.

LONG TERM...(Saturday through Tuesday)
Issued at 218 AM CDT WED APR 23 2014

Active weather expected in the long term. Regardless of the
noticeable model variance, with respect the the movement of an
upper low from the Rockies into the central states, and the
positioning of a surface front somewhere across/north of the
area, convection is pretty much a given. It will be just a matter
of timing and coverage. The past two runs of the GFS Ensemble mean
depicts reasonably, best chances should arrive late Sunday into
Sunday night, and shift east across the area early next week with
the approach of the upper low. This is not a classic heavy rain
pattern. But multiple rounds of convection, should they line out
favorably, could result in some heavy rain across the CWFA. Strong
storms cannot be ruled out at some point. Best chance may be
Monday should we destabilize enough. That is when a branch of the
upper jet SE of the parent H5 low moves over top of the area
coincident with potentially decent destabilization. It`s possible
Sunday as well (strong storms), mainly SE Missouri westward, but
wind fields are weaker. Meanwhile, given PoPs were removed for
Saturday, will not flip flop that. Not convinced we won`t see
anything (even if isolated at best), given we destabilize by mid
to late afternoon, esp SW 1/3 of the area and with the front
around. Moisture is certainly marginal, and mid level support is
hard to find. Chances Saturday night should be slight as well, and
primarily limited to the NW 1/2 of the area. Temperatures will
continue to be tricky. A blend approach would seem reasonable to
minimize swings due to model variance. However, hedging warmer
seems to be the appropriate trend.

Issued at 218 AM CDT WED APR 23 2014

High pressure will maintain VFR conditions with only scattered high
clouds expected during the TAF forecast period through this evening
with some increase in mid to high clouds thereafter. Winds will be 5
to 10 knots today and then relax to nearly calm levels tonight.




LONG TERM....CN is the U.S. government's official web portal to all federal, state and local government web resources and services.