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Area forecast discussion 
National Weather Service Wichita Kansas
1249 PM CDT Monday may 25 2015

..updated for 18z aviation discussion...

Update...
issued at 954 am CDT Monday may 25 2015

Lots of mesoscale features are making to a rather difficult forecast
this morning...with lots of low level moisture present across the
area. Latest surface analysis and rapid scan visible satellite data
shows a weak outflow boundary situated just south of the Kansas/OK line
at this time...from Medicine Lodge to near Enid OK to kpnc.
Already seeing 2000 j/kg of SBCAPE pooling just south of this
boundary and with afternoon heating expect this area to become very
unstable. Latest hi-res short term models arent handling this
outflow very well...basically washing it out. But current
observations suggest it will still be around. Not alot of
capping...so with the heating of the day...think storms will develop
along boundary...with multicell clusters the main storm Mode. If a
storm can move northeast...into south central Kansas...surface winds out of
the southeast and east may be enough to increase directional shear for a
stray supercell to get going. 0-6km shear isnt all that
impressive...only around 20-25kts...but given the high
instability...some supercell characteristics may be possible...which
may enhance the severe weather and maybe even a very isolated
tornado chance this afternoon.

Will have to keep an eye on things as the afternoon progresses as
cirrus shield from central Texas mesoscale convective system may limit afternoon heating in
south central Kansas. But given the lack of much capping...could see
storm isolated storm development by early this afternoon.

Will also see storms become more widespread later this evening...as
low level jet increases across central Kansas. And also storms across
southeast Kansas...as an impulse in western Texas begins to lift NE into SW MO.

Any convection that gets going will pose a heavy rainfall
threat...given the high precipitation water values or 120% of normal and
slow movement to the convection.

Ketcham

&&

Short term...(today through wednesday)
issued at 339 am CDT Monday may 25 2015

Active and challenging forecast through the next several
days...with periodic episodes of showers/thunderstorms expected
through at least late week/early weekend.

Early morning radar mosaic indicates a compact thunderstorm
complex racing east/northeast from southwest into central Kansas.
Thinking this activity will continue through primarily central
into east/northeast Kansas early this morning...aided by 900-800mb
warm/moist advection and a vorticity lobe skirting northwest Kansas. Not
expecting widespread severe weather with this activity...although
cannot rule out a few 50-60 miles per hour wind reports and locally heavy
rain. Activity should tend to dissipate with time early this
morning...as it outruns better instability.

Attention then turns to thunderstorm chances this afternoon
through tonight. Current mesoscale convective system will likely lay down a weak outflow
boundary across the region this morning...but persistent southerly
flow should gradually dissipate this boundary...allowing for
strong destabilization by mid-afternoon. Meanwhile...a weak cold
front will approach from the northwest...as additional upper
support approaches from the west/southwest. There are some
concerns that expected widespread afternoon convection over
Oklahoma will limit destabilization...although thinking there is
enough residual moisture in place to mitigate this concern.
Consequently...scattered thunderstorms are expected to form by
middle-late afternoon along the front across central Kansas...with
possibly another area of storms over southeast Kansas ahead of
approaching pv anomaly. The strong instability coupled with
weak/modest deep layer shear will favor strong to severe multi-
cell storms with supercell structures...especially over central
/north-central Kansas where steeper middle-level lapse rates will reside.
Activity should tend to exit the region to the east/northeast
overnight.

Model consensus stalls the outflow boundary/front somewhere
across southern Kansas for Tue-Wed...which should allow for renewed
scattered convection each day...especially from middle/late afternoon
into the overnight hours. While deep layer shear will remain on
the marginal side...potential degree of instability will favor a
few strong/severe storms along with locally heavy rain.

Adk

Long term...(thursday through sunday)
issued at 339 am CDT Monday may 25 2015

Active pattern is expected to continue through late week/early
weekend...as longwave troughing establishes itself once again over
the western Continental U.S....sporadically ejecting subtle upper shortwaves
across middle- America amidst a moist/unstable airmass. Despite some
differences between the GFS/European model (ecmwf) regarding upper pattern
evolution...consensus suggests the potential for periodic episodes
of showers/thunderstorms. Signal is low for widespread severe
weather given marginal deep layer shear...although degree of
instability will favor a handful of strong/severe...along with the
continued threat for locally heavy rain.

Adk

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1247 PM CDT Monday may 25 2015

Low level moisture remains high across the forecast area...which has
led to some scattered MVFR ceilings lingering or slow to burn off across
central Kansas. So will keep some 2500 foot above ground level ceilings across central Kansas
for now.

The next concern will be the chance for thunderstorms and rain across the area late
afternoon into this evening...as an unstable airmass remains in
place. Expect convection to become more widespread for the evening
hours as heating increases. Hard to pinpoint exact location of
greatest thunderstorms and rain coverage...so prefer to go with thunderstorms in the vicinity for all locations
this evening. Expect most of the convection to diminish late this
evening or overnight...but with low level moisture remaining
high...expect to see MVFR ceilings redevelop for most locations early
Tuesday morning.

Ketcham

&&

Hydrology...
issued at 339 am CDT Monday may 25 2015

Will cancel current Flash Flood Watch...which was slated to
expire at 7 am. However...with potential for additional
thunderstorms expected throughout the week...later shifts may need
to hoist additional flood/flash flood watches...given the already
saturated soils. Additionally...despite the fact that most rivers
streams are beginning to recede...the periodic episodes of
thunderstorms and locally heavy rain this week may allow for
renewed river flooding.

Adk

&&

Climate...
issued at 339 am CDT Monday may 25 2015

Through may 24th...Wichita may rainfall has accumulated 10.58
inches...3rd all-time (since 1889). 2nd is 11.22 inches in
1935...and 1st is 13.14 inches in 2008. With periodic episodes of
thunderstorms expected through the week...these records will be in
jeopardy. Salina and Chanute also have a strong potential of
breaking into the top-10 wettest may's on record.

Adk

&&

Preliminary point temps/pops...
Wichita-kict 80 60 79 61 / 20 20 30 30
Hutchinson 79 60 79 60 / 30 30 20 30
Newton 78 60 79 60 / 20 30 20 30
Eldorado 78 60 78 61 / 20 40 30 30
Winfield-kwld 80 60 78 62 / 20 30 30 40
Russell 78 57 78 58 / 40 40 20 20
Great Bend 77 57 78 58 / 40 40 20 20
Salina 79 60 79 59 / 30 40 20 20
McPherson 79 60 79 59 / 30 40 20 20
Coffeyville 78 62 79 63 / 20 50 30 40
Chanute 78 62 78 63 / 30 50 30 40
Iola 78 62 78 63 / 30 50 30 30
Parsons-kppf 78 62 79 63 / 30 50 30 40

&&

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

$$

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