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fxus63 kict 292005 
afdict

Area forecast discussion
National Weather Service Wichita Kansas
305 PM CDT Sat Apr 29 2017

Short term...(this evening through Tuesday night)
issued at 304 PM CDT Sat Apr 29 2017

Main forecast focus is the ongoing storm system.

Showers and thunderstorms continue across the eastern portion of
the County Warning Area. Ongoing convection remains below severe levels. Would
argue that some of these could be strong with the shear/buoyancy
combinations, but the most significant threat is well to the east
of the area.

The main focusing mechanism for the convection across southeast
Kansas is an inverted trough which extends north of a low which
was centered over eastern Oklahoma. Satellite/radar/observations
show a back edge to the main area of convection which extended
from about okc-ict-mci. This should continue moving east as the
system.

One thing of note was that on the back side of this trough, there
was a small mesoscale area of northeast winds gusting over 40
knots. This was noted on the WSR-88D where winds exceeding 50
knots were observed. This was very localized and at the moment and
is not seen in the observations.

Well behind this area of precipitation, a second area of forcing
and associated precipitation extends across western Kansas. Much
of this is snow with significant accumulations. This forcing is
associated with the main pv anomaly which is well back across the
4 corners region.

This is significant since the main forcing does not move across
the state until late tonight through morning Sunday. This means
that there remains very high confidence in significant
precipitation across the state through Sunday. Of note here this
the forcing depicted with this storm is one of the more prolific
q-vector convergence signals that I have seen.

As the storm exits, enough cold air will be brought into the County Warning Area
for snow to fall in central Kansas. This should accumulate along
and north of a line from Salina to Great Bend. Accumulations right
now are expected to be an inch or less.

The Flood Watch looks in good shape. Have received reports of over
2 inches or rainfall across the southern and eastern portion of
the County Warning Area. Many ditches are running full but no flooding has been
reported. We expected an additional 2-3 inches of rain through the
remainder of the storm, so flooding is still possible, and likely
along the rivers in that part of the state.

Storm bottom line: very high confidence in additional
precipitation, fairly high confidence in snow across central
Kansas with an inch or less of accumulation. Good confidence in
receiving anorth 2-3 inches across southeast Kansas. Storm should
exit the region Sunday night.

The next problems to deal with are the wind and low temperatures
Sunday night. Strong cold advection behind the front will push
temperature down toward freezing Sunday night across central
Kansas. Will have to monitor, but no frost expected with the
amount of wind expected. Soundings suggest enough momentum
transport for wind advisories Sunday afternoon and evening across
central Kansas.

Long term...(wednesday through saturday)
issued at 304 PM CDT Sat Apr 29 2017

The main challenge here is the system moving through the region
Wednesday. The European model (ecmwf)/GFS runs today trend further south and east
with the precipitation. And while that storm system does take a
similar track, the associated upper level disturbance is not
nearly is vigorous. This means less forcing and less
precipitation. Confidence is moderate at receiving additional
precipitation, higher for southeast Kansas. Severe storms do not
look probable at this time.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1251 PM CDT Sat Apr 29 2017

Messy/complicated aviation forecast with multiple flight impacts.
Fairly widespread IFR conditions are expected until upper low
departs. This is mainly due to ceilings, with visibilities
dropping to 1-2mi in heavier precipitation. Anticipate LIFR
ceilings in deformation band on the trailing edge of the low with
slow improvement on Sunday. Colder air and steep lapse rates will
result in a rain/snow mix at krsl/kgbd around daybreak. -Howerton

&&

Preliminary point temps/pops...
Wichita-kict 49 41 47 39 / 100 80 50 30
Hutchinson 46 38 44 37 / 100 80 60 40
Newton 47 40 45 37 / 100 80 60 40
Eldorado 51 43 49 38 / 100 70 50 40
Winfield-kwld 53 43 50 39 / 100 70 50 20
Russell 42 35 38 34 / 90 90 80 50
Great Bend 42 35 39 35 / 90 90 80 40
Salina 46 38 45 37 / 100 80 70 50
McPherson 45 38 44 37 / 100 80 70 50
Coffeyville 58 49 55 41 / 100 80 40 20
Chanute 55 48 55 40 / 100 90 50 30
Iola 53 48 55 40 / 100 90 50 30
Parsons-kppf 58 49 55 41 / 100 80 40 20

&&

Ict watches/warnings/advisories...
Flash Flood Watch through Sunday morning for ksz096-098>100.

&&

$$

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