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Area forecast discussion 
National Weather Service Wichita Kansas
647 PM CDT Wednesday Apr 23 2014

..updated for 00z aviation discussion...

Short term...(this evening through friday)
issued at 331 PM CDT Wednesday Apr 23 2014

This evening-tonight: latest surface analysis shows main
instability axis located from kgck to kgld. Visible satellite
shows cumulus field beginning to bubble up near kgld. Expect
thunderstorm development well to northwest of the forecast area late this
afternoon/early this evening as elevated mixed layer (eml) weakens
the cap. Bulk shear and instability suggests a severe hail/wind
threat for areas northwest of the forecast area for the evening hours.
Current short term models suggest that this convection will
gradually propagate east-southeast as the evening progresses...possibly
moving into central Kansas well after sunset. MLCAPE around 1200-1500
j/kg and bulk shear of 40 kts suggests some large hail potential
as the storms move into central Kansas...but dry low layers may lead
to increasing damaging wind threat as the cold pool develops and
low level jet feeds north right into this convection. Think any
severe chances in central Kansas...will be well after sunset..with
current severe watch in effect until 11pm.

Cold pool will push this convection to the east-southeast late this
evening...with severe hail threat diminishing...but a strong to
severe wind threat will continue as the storms develop into a
forward propagating mesoscale convective system (mcs) as it drops
southeast into south central Kansas. Think the primary damaging wind
threat will be north of Highway 50...not sure how far south the
severe wind threat will be....with some strong gusty winds across
south central Kansas as the storms move in after midnight. The mesoscale convective system will
gradually shift to the east as the overnight progresses...as the
low level jet begins to veer into the Flint Hills and eventually southeast
Kansas by early Thursday.

Thursday-Fri: not expecting much of a cool down after tonights system
pushes east of the forecast area during the morning hours on Thursday.
Could see some lingering showers and thunderstorms across
southeast Kansas for the morning hours...as remnant mesoscale convective system moves east
into MO. Most of the area on Thursday will be in the downslope
flow...which will lead to seasonal temperatures.

The weak ridging will continue over the area on Friday...for a nice
Spring day. Surface flow will gradually return to the southeast and
south for Friday afternoon with above normal maximum temperatures.

Ketcham

Long term...(friday night through wednesday)
issued at 331 PM CDT Wednesday Apr 23 2014

Friday night-Sun: it still looks like a very interesting
weekend...with several episodes of severe weather possible. A
stronger shortwave will move through the SW US and into the southern
rockies and the Southern Plains for the weekend. As this shortwave
approaches...rich low level moisture will surge north into the
plains...with 850-700h warm advection/ moisture transport
increasing late Friday into early Sat. This will lead to some
scattered showers and thunderstorms across the eastern half of Kansas for
late Friday night into early Sat. Bulk shear and elevated instability
suggests a possible strong/severe chance early Sat for areas over
the Flint Hills and southeast Kansas.

Attention will quickly turn to Sat afternoon...as both medium range
models continue to advertise that this deep trough will be located
in the southern rockies by Sat morning...with a very unstable airmass
flowing into Kansas for Sat afternoon. Current forecast trends
bring this system in a little slower into the plains...which will
lead to a significant dryline setting up to the west of the forecast
area for Sat afternoon/evening. Some differences on how far north
the warm front will get for Sat...but the system moving in slower
will allow the warm moist air to surge further north...placing most
of the forecast area in the warm sector for Sat afternoon/evening.

Think as middle level cooling increases...supercell storms will quickly
develop well to the west of the forecast area...with all forms of
severe weather possible...given the very unstable airmass and bulk
shear values. Some uncertainty Ohio how far east this severe threat
will get Sat night...but certainly think areas west of I-135 will be
under the gun Sat night...with some high end severe storms moving
into area after dark.

Medium range models show this dryline surging to the east on sun
pushing to near I-135 for Sun afternoon as the main shortwave surges
north-northeast with a negative tilt. Certainly think another round
of severe weather looks possible for Sun afternoon/evening for areas
east of I-135. Could see this convection develop alot earlier than
Sat possibly by early Sun afternoon. This will probably be the more
widespread severe day for the forecast area...as a very unstable
airmass will still be located ahead of the dryline...with better
upper level dynamics and bulk shear. Could see severe storm Mode
either be...closely spaced quick moving supercells or bowing line
segments...as flow is more unidirectional than on Sat with this
activity quickly racing to the northeast towards kmkc/ktop.

Monday-Tue: main upper low will slowly swing across the plains for
the start of the work week. Lots of moisture will still be
available underneath this low as the cold core nature of this low
moves across. This will lead to a cool and damp start to the week.
Cold core nature to this low could also lead to some diurnally
driven isolated storms directly underneath the upper low on Monday
afternoon across central Kansas.

Ketcham

&&

Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 639 PM CDT Wednesday Apr 23 2014

Strong southerly winds will diminish below advisory criteria
early this evening while remaining breezy through the night. Winds
will veer to the southwest ahead of a cold front while shifting to
the northwest behind the front. A squall line is anticipated along
the front with the highest probabilities for thunderstorms
expected across central Kansas impacting krsl and ksln after
04-05z. Winds will shift to the northwest behind the front with
clearing skies expected from west to east during the afternoon
hours on Thursday.

&&

Fire weather...
issued at 331 PM CDT Wednesday Apr 23 2014

Fire danger will be elevated over the next few days.

Very strong south winds will lead to an elevated grassland fire
danger late this afternoon into the very high category with extreme
fire danger anticipated for areas west of Interstate 135. Relative
humidity values across the area this afternoon will be in the upper
30s to around 40%. Sustained wind speeds will be in the 30-35 miles per hour
range with gusts around 45 miles per hour...especially along and west of
Interstate 135.

Gusty northwest winds will lead to a very high grassland fire danger
on Thursday afternoon over mainly central Kansas. Winds will again flip
around to the south for Friday and will increase...producing very high
fire danger across most of the forecast area.

Lawson/Ketcham

&&

Preliminary point temps/pops...
Wichita-kict 55 75 48 83 / 80 20 0 0
Hutchinson 52 74 47 83 / 90 10 0 0
Newton 53 73 48 81 / 80 20 0 0
Eldorado 56 74 47 81 / 70 20 0 0
Winfield-kwld 57 76 48 83 / 60 20 0 0
Russell 48 73 46 82 / 90 10 0 0
Great Bend 50 73 45 83 / 90 10 0 0
Salina 51 74 46 83 / 90 10 0 0
McPherson 52 74 46 82 / 90 10 0 0
Coffeyville 60 72 46 81 / 40 50 0 0
Chanute 59 72 45 81 / 50 60 0 0
Iola 60 73 45 80 / 60 60 0 0
Parsons-kppf 60 72 46 81 / 50 60 0 0

&&

Ict watches/warnings/advisories...
Wind Advisory until 8 PM CDT this evening for ksz032-033-047>052-
067-068-082-083-091-092.

Red flag warning until 8 PM CDT this evening for ksz032-033-047-
048-050-067.

&&

$$