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000
FXUS63 KTOP 281654
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1154 AM CDT Mon Jul 28 2014

...AVIATION UPDATE...

.SHORT TERM...(Today and Tonight)
Issued at 301 AM CDT MON JUL 28 2014

The short term period looks rather quiet, dominated by surface high
pressure drifting east across the area through tonight, and
persistent cool northwest flow. High temperatures today will be a
bit cooler than yesterday, with highs expected to range from near 80
in far northeast KS to around 87 in the Abilene/Minneapolis area.
Expect a few showers to develop under cold air aloft in southwest
Iowa, but this light activity should remain northeast of the
forecast area this afternoon. The surface ridge shifts into far
eastern Kansas by late tonight and the combination of calm winds and
clear skies in the east should allow temperatures to fall into the
upper 50s. It should stay a bit warmer with westward extent into
central Kansas as return flow on the west side of the ridge is
likely to result in increasing mid level cloud cover after 06Z.
There are also suggestions that a band of rain showers or
thunderstorms could develop across north central Kansas, with the
NMM/ARW/NAM leaning heavily toward precip development. However, even
within those models, the vertical motion is weak and so is the
elevated instability above the moist layer. Have gone with slight
chances for thunderstorms in this area late tonight in the event
that ascent is a bit stronger or instability is a bit
deeper/stronger.

.LONG TERM...(Tuesday through Sunday)
Issued at 301 AM CDT MON JUL 28 2014

For Tuesday, convective area that develops over Nebraska could
move southeast into north central KS during the morning hours and
have small chance POPs for that area. On Tuesday night and
Wednesday, trough in northwest flow aloft moves southeastward out
of the central Rockies into the High Plains. Isentropic lift ahead
of this system combined with upslope flow will produce greatest
QPF over western/southwestern KS. Our forecast area will be on the
northeast edge of this precip shield, and chances will likely be
tied to lift on warm side of 600-650 MB frontogenesis area.
Subsidence behind wave should dry things out Wednesday night.

Northwest flow aloft continues through Friday and then becomes
more northerly during the weekend. Medium range models have some
QPF over the eastern half of KS at various times, but there is
little consistency in placement and timing of these areas, at
least until Friday night or Saturday. During this time, as the
flow aloft transitions to the more northerly direction, a weak
shortwave trough moves across the eastern KS area with the
potential for some rainfall. While ECMWF and 00Z deterministic GFS
indicate QPF on Saturday, GFS Ensemble less certain and thus have
relatively low POPs for the early part of the weekend.

Temperatures in this northwest/northerly flow pattern continue on
the below average side with highs mainly in the 80s and lows in
the upper 50s to middle 60s.

&&

.AVIATION...(For the 18Z TAFs through 18Z Tuesday Afternoon)
Issued at 1154 AM CDT MON JUL 28 2014

Relatively dry air from surface ridging should allow VFR
conditions to prevail. Models hinting at mid level frontogenesis
and light showers overnight, but chances appear to be to small to
mention in the forecast at this time. With limited elevated
instability, impacts from any precip would appear to be minor.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...Barjenbruch
LONG TERM...GDP
AVIATION...Wolters