Area Forecast Discussion
Issued by NWS Paducah, KY

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FXUS63 KPAH 252220

520 PM CDT TUE AUG 25 2015

Issued at 518 PM CDT TUE AUG 25 2015

Updated Aviation Discussion for 00Z TAF Issuance.


.SHORT TERM...(This evening through Wednesday night)
Issued at 240 PM CDT TUE AUG 25 2015

As a deep stacked low over the Great Lakes/srn Canada moves toward
the Canadian Maritimes region and damps out, gradient nwrly flow
aloft between it and a swrn CONUS mid level ridge will continue
over the PAH forecast area for the next couple of days. This will
continue to provide mostly clear, dry, and unseasonably cool

The upper flow over the CONUS is progged to deamplify toward the
weekend, and therefore slacken over us by Thu. Low level winds
are expected to lessen, then pick up and turn to the south by the
end of the short term period as the airmass begins to moderate.
This set-up should provide a gradual warming trend, especially
with the overnight minimum temps. As dewpoints begin to tick
upward Thu, some patchy fog might be seen near rivers and lakes,
more toward Thu morning. No pcpn is forecast.

.LONG TERM...(Thursday through Tuesday)
Issued at 240 PM CDT TUE AUG 25 2015

The current amplified ridge west/trough east pattern will have
relaxed considerably by Friday. The flow Friday will run from the
Pacific Northwest eastward along the Canadian border. The 12Z models
continue to push a mid/upper-level disturbance southeast into our
region Friday night, and as the upper-level ridge continues to build
our way this disturbance gets cut off from the primary flow aloft.
It would not be out of the realm of possibility that it would be
stuck in our region through the remainder of this forecast period,
similar to the 12Z GFS.

That said, the 12Z GFS is quite dry through the period. A look at
12Z GFS soundings across our region indicates that there will be an
increase in moisture/clouds above 700mb Friday night into Saturday.
However, there will be extremely dry air in the lowest 10kft, so it
is unlikely that any measurable rainfall would reach the ground.
Beyond Saturday a strengthening mid-level cap will effectively
bottle up only modest low-level moisture expected Sunday through
Tuesday. The newly arrived 12Z ECMWF is substantially dry over the
weekend, but spreads moisture and QPF northward through the area
next Tuesday.

Will try to keep the forecast as dry as possible, but will have to
keep very small pops along the northwest and north border regions
Saturday and over the extreme northeast Saturday night.

The surface ridge will barely be holding on Friday, as temperatures
will climb up into the middle 80s or very close to normal levels
over much of the region. By Saturday temperatures will be back to
normal levels if not a few degrees above. As the upper-level ridge
really takes over, upper 80s to around 90 will be the rule for
Sunday into next week.


Issued at 518 PM CDT TUE AUG 25 2015

GFS Model Curule has done a good job depicting the diurnal cu
field each of the last two afternoons. Tmrw it depicts its
expansion further south/west into the flight area...with probable
cigs at KEVV/KOWB and scattered decks at KPAH and KCGI...with
cloud bases around 5K FT AGL. Otherwise little/no cloud or wind
and likely we`re still dry enough to preclude fog mention
tonite...though it`s something to monitor as the night progresses.



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