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Area forecast discussion 
National Weather Service Wichita Kansas
1109 PM CDT Wednesday Apr 1 2015

..updated for 06z aviation discussion...

Synopsis...
issued at 321 PM CDT Wednesday Apr 1 2015

Last night a mesoscale convective system moved across Oklahoma and a remnant mesoscale convective vortex sparked
convection late this morning which has turned into another complex
this afternoon. This complex skirted southeast Kansas and is
mainly impacting Missouri. A surface trough/low and associated
cold front/dry line drapes across central Nebraska southward into
western Kansas. Southerly winds are Stout ahead of this front and
temperatures are soaring well into the low to middle 80s.

Billings Wright

&&

Short term...(this evening through saturday)
issued at 321 PM CDT Wednesday Apr 1 2015

The main short term forecast concerns will be focused on tonight
and tomorrow.

Tonight:
the main question/concern is initiation time and then track of the
convection. Have been watching the latest high-resolution short-
term models closely all day and they have been showing a lack of
convection developing along the dry line over western
Kansas...however the latest hrrr/18z Sparks convection late this
afternoon...and tracks it eastward across Kansas. This cannot be
ruled out as there is already cumulus bubbling along the dryline across
western Kansas with modest cape and minimal cin. The main missing
component further south along the dryline is adequate bulk
shear...that remains further north in northern Kansas and
Nebraska. Thus...despite this latest hrrr...the forecast has
convection increasing and approaching central Kansas towards
22-23z. Confidence has been that it would be a later
show...between 00-03z...but the latest guidance and satellite
trends could trend that to the earlier side.

As mentioned earlier...the best cape/shear combo is across
northern Kansas and in Nebraska...so the best chances for severe
storms will be in those areas which would include central Kansas.
Other areas might see some stronger storms. Going along with that
the area for the greatest confidence in location is in central
and northeastern Kansas tapering off to the south.

Thursday:
the front and associated upper disturbance will move through the
area tonight. However...thinking the front will stall out across
southeast Kansas. Storms may linger across southeast Kansas in the
morning...but the bigger concern is that the front will serve as a
focus for thunderstorm development during the afternoon Thursday.
And this time the cape and shear will be plentiful for severe
storms.

Thursday night - saturday:
another disturbance will cause showers to develop across
northwestern Kansas and track southeastward across the area
Thursday night into Friday morning. The cape will reside
southward near the front and so these will just remain showers in
central Kansas. This disturbance will move through by Friday
afternoon and it will clear out.

Temperatures will cool down Thursday and Friday behind the front
and with the precipitation before warming again on Saturday with
clear skies and light winds.

Billings Wright

Long term...(sunday through wednesday)
issued at 238 PM CDT Wednesday Apr 1 2015

Upper level pattern shifts to more of a southwest flow regime across
the nation next week. This will bring additional precipitation and
severe weather chances to the region.

As far as the details are concerned...surface high pressure moves
through the region during the end of the week. On Sunday...Lee
cyclogenesis occurs with an open Gulf of Mexico...which will
increase dewpoints ahead of the next system. By late
Sunday...surface dewpoints are expected to recover into the 50s.
Confidence is pretty high that this will occur given that all of the
longer range forecasts and ensembles show good surface flow off of the
Gulf.

At that point...confidence in what will occur hereafter really GOES
down. The GFS and most of its ensemble members all move the surface
low well north into Nebraska. The Canadian also agrees with this
scenario. That said the European model (ecmwf) is much slower to evolve and keep the
surface low back to near Goodland Kansas. This latter scenario is much
more favorable for convection across the area given that the low
level wind field will be much more convergent along the dryline
versus the other scenario.

Thus far...am inclined to keep a low chance of storms in the
forecast. If they do develop...there is a high likelihood that they
will be severe...especially with the latter scenario given the
added shear with the surface low closer to the forecast area.

Tuesday looks like a repeat of Monday only that the surface features
are further east. The European model (ecmwf) continues to present a better scenario
for severe weather across the forecast area...especially along and
east of the Kansas Turnpike.

Krc

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1102 PM CDT Wednesday Apr 1 2015

Cold front extending from southeast Nebraska into northwestern
Kansas late this evening...will push southward overnight and may
stall near the Kansas/OK border Thursday afternoon. Thunderstorm
coverage along the front overnight will be most numerous over
northern/eastern Kansas. Will include tempo thunderstorms and rain at
rsl...sln...and cnu terminals. Winds will shift to northerly
overnight behind the front with gusts of 30-35 knots in central Kansas
where pressure rises are prognosticated to be strongest. Low stratus may
form over southeast Kansas during the morning hours with most models
indicating IFR or low MVFR at cnu.

Scattered storms will be possible Thursday late PM/evening near the
Oklahoma border...depending on exactly where the front hangs up.

Jmc

&&

Fire weather...
issued at 238 PM CDT Wednesday Apr 1 2015

Grassland fire danger continues to be a concern throughout the
next few days. A red flag warning remains in effect this afternoon
for much of the area. Depending on northerly winds strength behind
the cold front a brief reprieve may be felt on Thursday...if the
winds are stronger then very high fire danger will be
expected...but as it is that is only the case for a few hours in
the morning. Any precipitation that falls will hopefully mitigate
these issues for a short while.

By Friday and Saturday the precipitation chances end...and while
some areas may have received a good amount of rain...any areas
that did not...could again see a return to very high to extreme
fire danger...especially across central and south central Kansas
with stronger winds.

Billings Wright

&&

Preliminary point temps/pops...
Wichita-kict 57 72 46 60 / 20 20 40 20
Hutchinson 53 70 43 60 / 30 10 50 20
Newton 54 70 44 57 / 30 10 50 20
Eldorado 58 72 46 59 / 30 20 50 20
Winfield-kwld 60 74 48 60 / 20 30 60 20
Russell 47 70 39 59 / 50 10 50 20
Great Bend 48 71 40 59 / 40 10 40 20
Salina 50 70 41 59 / 60 10 40 20
McPherson 52 68 42 58 / 40 10 50 20
Coffeyville 61 77 50 59 / 30 60 70 30
Chanute 60 74 48 59 / 50 50 70 30
Iola 60 72 47 58 / 60 50 70 20
Parsons-kppf 61 75 49 59 / 30 50 70 30

&&

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

$$

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