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fxus63 kict 131117 

Area forecast discussion
National Weather Service Wichita Kansas
517 am CST Wed Dec 13 2017

Short term...(today through Friday night)
issued at 330 am CST Wed Dec 13 2017

the focus remains on elevated grassland fire danger in central Kansas
this afternoon. For details please refer to "fire weather" section
that appears at the end of this discussion.

The upper-deck longwave trough deeper than the marianas trench is
moving slowly east toward the Atlantic coast. At 2 am, the trough
extended from the Ontario/Quebec border to just off the mid-
Atlantic coast. The wave has begun to take on a negative tilt. The
ultra-high amplitude upper-Deck Ridge that has been parked over
the western U.S. Is slowly retrograding toward the Pacific coast.
The pattern continues to keep the Great Plains under a strong northwest
regime that is sending another clipper sailing across the northern
plains. The strengthening surface cyclone moving from the Dakotas
to the lower Great Lakes will send a NE-SW oriented trough across
Kansas this morning. The northwest gradient in the wake of the trough is
fairly tight & will cause the northwest winds to increase. Though close,
the winds should remain below advisory criteria. The downslope
component would produce warmer weather especially in southeast Kansas.

the next southeast-sprinting mid-level shortwave will spread extensive
clouds into Kansas late tonight but won't offset the cold advection to
prevent lows from reaching around 30. The lowest ~10,000ft of the
airmass remains predominantly dry. As such dry weather continues.

Thu & Thu night:
with the clipper approaching the mid-Mississippi Valley Thu would
be much cooler with highs in the lower to mid 40s. A 925-850 mb
moisture axis moves southeast across Kansas Thu afternoon & Thu night. There
is sufficient lift associated with the approaching & strengthening
upper-deck trough to produce some light rain across central Kansas in
the afternoon and south-central & southeast Kansas Thu evening. The
effects of the clipper would be felt strongest Thu night with lows
in central Kansas near 20, but because of the fast-moving mid-level
short wave the rain would be short-lived & would vacate the area
before sub-freezing temperatures arrive.

Fri & Fri night:
the work-week ends on a dry note as the western U.S. Ridge, though
deamplifying, spreads rapidly east across the northern plains. The
onsetting & deepening westerly mid-upper flow would produce
slightly warmer temperatures areawide.

Long term...(saturday through tuesday)
issued at 330 am CST Wed Dec 13 2017

This weekend:
the first really legitimate chance for precipitation to occur this
month should arrive Sat night as the next mid-upper wave, which
would force the deamplifying upper-Deck Ridge east across the
northern plains, strengthens greatly as it digs from the northern
plains to the Desert Southwest. The rapidly-deepening wave will
send a cold front southeast that may find sufficient moisture to produce
rain, especially across southeast Kansas Sat night. A transition to
light snow would occur across central Kansas late Sat night with light
rain/light snow mixture pictured for most of south-central and
southeast Kansas. Because of the rapid progressive pattern, all
precipitation should depart southeast Kansas Sun morning.

Mon-Tue night:
dry & slightly warmer weather returns to Kansas as predominantly
westerly flow spreads across the region.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 517 am CST Wed Dec 13 2017

North to northwest winds will increase behind a cold front by
midday through the afternoon across central and southeast Kansas.
Winds will diminish this evening after sunset. An increase in mid
and high level clouds can also be expected later today into



Fire weather...
issued at 330 am CST Wed Dec 13 2017

The passing surface trough will induce winds to become
northwesterly & increase considerably later this morning. The warm
dry advection coupled with sustained speeds from 20 to 30 mph will
cause the grassland fire danger to briefly reach the "extreme"
category in parts of central Kansas early this afternoon, especially
in Lincoln & Russell counties. The short duration (around 1 pm) of
the extreme fire danger dictates not hoisting the red flags for
these areas.


Preliminary point temps/pops...
Wichita-kict 61 31 46 27 / 0 0 10 20
Hutchinson 61 29 46 25 / 0 0 10 20
Newton 60 29 44 25 / 0 0 10 20
Eldorado 60 29 44 26 / 0 0 10 20
Winfield-kwld 62 30 46 27 / 0 0 0 10
Russell 60 28 45 21 / 0 0 20 10
Great Bend 60 28 46 21 / 0 0 20 10
Salina 60 29 45 25 / 0 0 20 20
McPherson 60 28 45 24 / 0 0 10 20
Coffeyville 63 30 44 27 / 0 0 0 10
Chanute 60 30 42 27 / 0 0 10 10
Iola 59 29 42 26 / 0 0 10 10
Parsons-kppf 62 29 43 26 / 0 0 10 10


Ict watches/warnings/advisories...none.


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