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Area forecast discussion 
National Weather Service Wichita Kansas
646 PM CDT Sat Apr 18 2015

..updated for 00z aviation discussion...

Synopsis...
issued at 358 PM CDT Sat Apr 18 2015

Strong thunderstorms...which may obviously achieve severity...have
developed over parts of central & south-central Kansas west of I-135.
As was expected...the thunderstorms developed in areas where skies
had cleared and with 55-60f dewpoints destablization was fairly
rapid. At 252 PM CDT ping pong Ball-sized hail was reported in
Barton County.

&&

Short term...(this evening through tuesday)
issued at 358 PM CDT Sat Apr 18 2015

Tonight:
obviously severe thunderstorms are drawing greatest attention. The
well-defined middle-upper cyclone that has been a topic the past 3 or
4 days is drifting toward the Colorado/Kansas border to promote decent upper
deck diffluence. With the attendant surface low still situated
over eastern Kansas inducing modest east-southeast lower-deck flow...deep-layer
shear...both speed and directional...should slowly increase with
30-40kts likely by early this evening. With modest upper-deck cold
advection approaching central & south-central Kansas large hail
perhaps 2 inches in diameter...would be the primary threat. Most
facets of inherited forecast are kept intact. Late tonight the
upper-deck low over eastern Colorado will evolve into a wave as it
phases with a 2nd upper-deck wave sweeping east across the
Saskatchewan/Manitoba border. Both will team to sweep a cold front
southeast that should extend from central Nebraska and western Kansas
early Sunday morning.

Sunday & Sunday night:
the southeast progress of the cold front will be watched closely.
As the 2 upper waves phase the southern cohort would weaken. This
would likely cause the cold front to decellerate as it approaches
southeast Kansas early Sunday afternoon. The NAM depicts this scenario
more so than it's cohorts and is being followed. As such the air
mass over southeast Kansas would destabilize considerably. As such
severe thunderstorm for southeast Kansas would increase considerably
& with the NAM preferred MLCAPES from 2,000-2,300 "carat jewels"
are likely early Sunday afternoon. Combined with modest upper-deck
cold advection targeting this area large hail...perhaps Golf Ball
sized...would be the primary threat Sunday afternoon. As the cold
front pushes southeast of this area deep brisk northwest flow spreads southeast across
Kansas thereby shunting the severe threat S-southeast of kict country early
Sunday evening.

Monday-tuesday:
the work-week should start quietly as an intense middle-upper cyclone
begins to gyrate over the Great Lakes per GFS & European model (ecmwf). This would
drive large bu weak high pressure east/southeast across the central &
Southern Plains.

Long term...(wednesday through saturday)
issued at 358 PM CDT Sat Apr 18 2015

Thunderstorms should return to the neighborhood Wednesday & Wednesday night
but with differences in solutions have kept forecast essentially
unchanged.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 641 PM CDT Sat Apr 18 2015

Mesoscale complex of thunderstorms over central/south central
Kansas...should progress slowly eastward overnight...as a weak low-
level jet develops and gradually veers northeast. Ict and cnu
terminals stand the best probability of being impacted by
thunderstorms. Winds will be highly variable overnight behind
outflow boundary in central/south central Kansas. Additional
thunderstorms could affect cnu terminal Sunday...with widespread
showers developing over central/south central Kansas as the upper
trough advances eastward through eastern KS/OK.

Jmc

&&

Fire weather...
issued at 358 PM CDT Sat Apr 18 2015

Prolonged periods of rain & thunderstorms will keep the grassland
fire in check.

&&

Preliminary point temps/pops...
Wichita-kict 55 64 40 62 / 80 80 10 0
Hutchinson 53 60 39 62 / 80 70 10 0
Newton 54 61 40 60 / 80 80 10 0
Eldorado 55 67 42 62 / 80 90 10 0
Winfield-kwld 55 68 41 63 / 80 90 10 0
Russell 52 60 37 61 / 70 80 10 0
Great Bend 51 60 36 60 / 70 70 10 0
Salina 53 60 39 62 / 80 70 10 0
McPherson 53 59 39 61 / 80 70 10 0
Coffeyville 57 68 43 64 / 70 80 20 10
Chanute 57 68 43 63 / 70 90 20 10
Iola 57 67 43 62 / 70 90 20 10
Parsons-kppf 57 68 43 63 / 70 80 20 10

&&

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

$$

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