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fxus63 keax 260811 

Area forecast discussion
National Weather Service Kansas City/Pleasant Hill MO
311 am CDT Mon Aug 26 2019

issued at 307 am CDT Monday Aug 26 2019

An active period will commence this afternoon and evening as storms
develop along a cold front, capable of producing damaging winds,
large hail, along with a few tornadoes.

Low-level moisture continues to linger across the area as of early
Monday morning. Areas of fog will impact the early morning commute
before slowly dissipating by the mid-morning as a warm front lifts
north into the region. As the front lifts north, dew points will
rise 10 to 12 degrees for areas south of I-70, which combined with
an already present eml from the southwest, will create a strongly
destabilized environment by the afternoon, with MLCAPE values
exceeding 4000 j/kg south of the warm front. A deepening mid-level
trough across the northern plains will permit a speed Max to dip
south over northern to central Missouri, leading to strong mid to
upper-level westerlies and resulting 0 to 6 km bulk shear values
in the 40 to 50 knot range. Southwesterly surface winds underneath
strong westerly flow aloft will also yield 0 to 1 srh values of
100 m2/s2, mainly across central Missouri. Low local heights are
also expected given increasing dew points and lingering low-level
moisture in the area. All said, the environment will be ripened
for all modes of severe weather as the cold front pushes through
the area this afternoon and evening. One item Worth considering is
the role that a decaying mesoscale convective system from the northwest will play into
interaction with the warm front later this afternoon and evening.
Currently thinking that the complex will enter northwest and later
central Missouri this morning. Lingering storms with this may be
ongoing as the cold front arrives into the northwest Missouri
later this afternoon. Will need to monitor how far north the warm
front makes it this afternoon, and the placement of any west to
east outflow boundaries present from the morning mesoscale convective system. This could
enhance the potential for tornadic activity considering any
boundary interaction, particularly for eastern Kansas and western
Missouri. Storms should initially be fairly discrete with a few
supercells possible. This would increase both the potential for
large hail and tornadoes early in the event. As the afternoon and
evening progress, the line of storms should fill in along the
front and the main hazard would then shift to damaging wind
potential. Last but not least will be the potential for flash
flooding toward the latter half of the event. Although the frontal
passage will be progressive, rainfall averaging near half an inch
to three quarters of an inch has fallen in the last 24 hours,
thus sensitizing flash flood guidance values ahead of today's
event. Forecast precipitable water values will also approach 2 inches as
moisture builds ahead of the frontal boundary. Main takeaway is to
prepare for all modes of severe weather and have a way to receive
warning information this afternoon and evening, including during
the evening commute time frame.

Cooler temps will remain in place through the mid to late week in
the wake of today's frontal passage as broad surface high pressure
builds into the area. The next chance for precip will hold off until
Friday and into the weekend as another cold front approaches the


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1216 am CDT Monday Aug 26 2019

IFR/LIFR cigs are expected to prevail thru the afternoon before
lifting to MVFR in the afternoon. Light fog will also be poss thru
the morning hours reducing vsbys to 4-5sm. Two rounds of
thunderstorms are poss thru the taf pd the first will come btn
15z-18z tomorrow morning with a stronger round of thunderstorms
expected aft 20z. Winds will be lgt and vrb thru the overnight
before picking up out of the southeast around 10kts in the morning. Durg
the afternoon winds will shift to the S around 10kts before veer
to SW by late afternoon and then to northwest behind a cold front that is
expected to move thru the terminals btn 21z-23z.


Eax watches/warnings/advisories...

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