Scientific Forecaster Discussion
fxus63 ksgf 261141
Area forecast discussion
National Weather Service Springfield MO
641 am CDT Fri may 26 2017
..12z aviation update...
Short term...(today and tonight)
issued at 231 am CDT Fri may 26 2017
Surface low pressure across the plains and an upper level short
wave were acting to shift the upper ridge that was over the
region yesterday to the east of the Ozarks. The surface low
however, is expected by the models to make little to no progress
to the east through today, keeping the Ozarks and southeastern
Kansas in the warm sector south of the warm front now across
A few storms over northeastern Kansas early this morning were
moving to the east. Mesoscale and short range models were not
handling this well at all this morning. The GFS did show some
depiction of the storms, but will need to see if they can hold
together with the current hostile environment over the Ozarks
The southerly flow will help bring more moisture from the Gulf
into the region through the day today. A strong capping inversion
noted on last evening's sounding and continued by the forecast
soundings through tonight should keep storms from forming through
today and through tonight. If a storm or two do develop, they
will be elevated in nature with large hail the primary concern.
Long term...(saturday through thursday)
issued at 231 am CDT Fri may 26 2017
Today's surface low is expected to wash out leaving a
stationary/warm front across central Missouri as Lee cyclogenesis
occurs and another surface low develops over eastern
Colorado early Saturday morning. Deep southerly to southwesterly
flow will continue to pump moisture into the region through early
Saturday as the surface low moves across the plains.
A strong low level jet will begin to impinge on the region as
several short wave troughs move through the upper level
southwesterly flow and across the Ozarks. Forecast soundings have
been consistent in showing a very unstable airmass in place
across the region Saturday afternoon and evening with 3800 to 4500
j/kg of ml cape. Increasing low level convergence and a weakening
cap will act to kick off thunderstorms Saturday afternoon and
continue into the evening. Indications and sounding analogs have
shown a consistent signal for large hail to the size of baseballs
and a damaging wind signal. Much of this will depend on the Mode
the storms ultimately take. More wind damage with bowing segments
verses large hail with more clusters or individual supercells.
This will be more of a mesoscale forecast issue to watch Saturday.
The system looks to move through the region by Sunday morning to
early Sunday afternoon depending of your model of choice. Either
way, this will lead to the potential for lingering thunderstorms.
Overall, the end of the Memorial Day weekend looks to be fairly
nice with temperatures in the middle to upper 70s Sunday and
Monday with skies becoming partly cloudy later Sunday and mostly
sunny on Monday.
The first half of next week looks fair as well with the next
potential for rain and storms coming Thursday into Friday. This
will be the result of a warm front over the area and an upper
level trough moving across the plains.
Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 641 am CDT Fri may 26 2017
Although cloudy, think the bases will remain in the VFR range at
least through the daylight hours. Southerly low level flow of
10-15kts expected. Flow will relax overnight, however, there is
some signal of lower visibilities by around sunrise or slight
before Saturday morning. Becoming more confident in MVFR/IFR
conditions early Saturday as cloud bases lower with increasing low
level moisture. There is a very slight chance of convection later
today, however, this should be very isolated/brief and nature and
should be sufficiently covered with vcs.