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Area forecast discussion 
National Weather Service Wichita Kansas
1135 PM CDT Tuesday Jun 30 2015

..updated for 06z aviation discussion...

Synopsis...
issued at 355 PM CDT Tuesday Jun 30 2015

This afternoon...strong(!) Upper-deck high pressure centered over
Utah is teaming with a deep upper-deck trough extending from southern
Ontario to the Gulf Coast from MS to Florida to place the Great Plains
under a pronounced northwest flow regime. A weak middle-level shortwave that
is slowly developing as it moves southeast Wyoming & Colorado toward the panhandles
is inducing weak low pressure to develop over the Western Plains.
The prevailing west-SW 10-20 miles per hour lower-deck flow has helped kick
temperatures to around 100 in central & south-central Kansas with
Lower-Middle 90s residing over southeast Kansas.

&&

Update...
issued at 1011 PM CDT Tuesday Jun 30 2015

Current forecast looks on track...with a back door cold front trying
to push into NE Kansas at this time. The nocturnal convection over northwest MO
will help reinforce this boundary overnight...as any outflow pushes
west. Middle level isentropic lift will increase across central Kansas by
12z/Wed. This may lead to a chance of showers and thunderstorms
developing across central Kansas near ksln by around daybreak as lift
increases in the middle layers along this synoptic surface boundary.

Could see this thunderstorms and rain chance increase some along a ksln to kcnu line
as the morning progresses on Wednesday. Current forecast seems to have
this scenario well in hand...so no changes made.

Ketcham

&&

Short term...(this evening through friday)
issued at 355 PM CDT Tuesday Jun 30 2015

Forecast highlight:
severe thunderstorm potential increasing for southeast Kansas Wednesday
afternoon & Wednesday night.

Tonight:
the best chances for strong-severe thunderstorms should occur from
the Dakotas...across eastern Nebraska & Iowa...to MO as a 2nd middle-
upper shortwave scoots S/se. This character would have ample fuel
to work with to promote mesoscale convective system development over these areas where no
doubt better aligned with lower-deck moisture axis. Southeast Kansas
positioned along the western periphery of the moisture channel
dictates ~20% pop assignment toward daybreak.

Wednesday & Wednesday night:
severe thunderstorm potential is increasing for southeast Kansas. With
the middle-level shortwave slowly strengthening as it surges S/southeast the
6km bulk shear would increase. Airmass destabilizes considerably
with MLCAPES likely to reach 3500-4000 j/kg late Wednesday afternoon.
With 6-km bulk shear increasing to ~35-40kts severe thunderstorms
are likely to erupt & with a cold front venturing into southeast
Kansas the directional shear would likewise greatly increase. Such a
profile would certainly favor supercells over southeast Kansas late
Wednesday afternoon & evening. Southeast Kansas may expect a severe trifecta
of large hail (perhaps golfball-sized)...damaging winds & a couple
tornadoes late Wednesday afternoon & evening.

Thursday-Friday night:
confidence on positioning of greatest of gereatest thunderstorm
potential is average at best as lower-deck flow is weak & this is
compounded by convective contamination. As such have 30-40% probability of precipitation
assigned to most areas throughout these periods.

Long term...(saturday through tuesday)
issued at 355 PM CDT Tuesday Jun 30 2015

With multiple...albeit weak...shortwaves traversing the region
thunderstorms are possible for most periods. The greatest chances
appear slated from Monday-Tuesday when the strongest upper-deck trough of
this forecast cycle will undergo intense cyclogenesis (per ecmwf)
as it surges east across northern Ontario on Monday. Nearly all facets
of the fofrecast for these periods has been kept intact.

Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1154 am CDT Tuesday Jun 30 2015

VFR conditions expected to prevail through the forecast valid period.
A light to moderate south to southwest surface wind flow is
expected today and tonight. The plume of smoke/aerosols from the
Canadian wildfires will continue to stream south and settle out a
bit in the northerly flow aloft...providing hazy skies and some
VFR visibility restrictions below 10sm across far eastern Kansas...
perhaps affecting the kcnu terminal at times. Nocturnal convection
across the northern plains is expected to move southeast across
the lower Missouri Valley Wednesday morning. Mesoscale outflow is
expected to enhance or augment the effective surface front moving
south into Kansas Wednesday morning...pushing the boundary into
north central and east central Kansas by the end of the forecast
valid period. So have shown a backing surface wind along the I-70
corridor with thunderstorms in the vicinity at ksln.

Ked

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1133 PM CDT Tuesday Jun 30 2015

Nocturnal convection across the northern plains is expected to drop
southeast across the lower Missouri Valley by Wednesday morning. Any
mesoscale outflow boundary is expected to enhance or augment the
effective surface front moving southeast into Kansas by Wednesday
morning...pushing this boundary into east central Kansas by the end
of the forecast valid period. So will go with a thunderstorms in the vicinity for initially
ksln as middle level lift increases. Will also go with a thunderstorms in the vicinity for kcnu
for most of the afternoon hours...as a middle level impulse pushes
south along the main synoptic front.

Ketcham

&&

Preliminary point temps/pops...
Wichita-kict 76 99 72 92 / 10 20 20 30
Hutchinson 75 98 70 91 / 10 20 10 30
Newton 75 97 71 90 / 10 20 10 30
Eldorado 75 97 71 90 / 10 20 20 30
Winfield-kwld 76 100 73 93 / 10 20 30 30
Russell 74 96 70 90 / 10 10 10 40
Great Bend 75 97 70 91 / 10 10 10 30
Salina 74 93 70 89 / 10 20 10 30
McPherson 75 96 70 90 / 10 20 10 30
Coffeyville 74 94 72 89 / 20 30 30 30
Chanute 73 94 71 88 / 20 30 40 30
Iola 73 94 71 87 / 30 30 40 30
Parsons-kppf 74 94 72 89 / 20 30 40 30

&&

Ict watches/warnings/advisories...
none.
&&

$$

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