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fxus63 keax 271130 
afdeax

Area forecast discussion
National Weather Service Kansas City/Pleasant Hill MO
630 am CDT Tue Jun 27 2017

Discussion...
issued at 403 am CDT Tuesday Jun 27 2017

A nice, quiet day is in store for everyone today has high pressure
has settled in over the area. As the high moves southeast today,
winds will shift to the south, starting a warming trend. Today,
temperatures will warm into the low 80s. This is still below
average, but warmer than what we have been experiencing the past few
days. High temperatures for the rest of the week will warm to the
upper 80s Wednesday and Thursday before cooling slightly to the low
to mid 80s for the weekend. Lows will start off in the low 70s but
will cool to the mid 60s for the weekend.

Wednesday through Friday, a more active pattern is expected to set
up. It all starts tonight with our area transitioning into the warm
sector of a Lee side low taking shape across the Central Plains.
This will coincide with an upper level shortwave trough and 850 mb
low level jet, resulting in nocturnal convection. We likely won't
see this activity until after midnight and it should stay mainly
north of I-70. This activity should dissipate by the late Wednesday
morning hours. If the morning's activity and cloud cover stick
around longer than anticipated though, the advertised afternoon
convection could be weakened or suppressed. Right now though, models
indicate the morning storms dissipating and a weak cap forming,
eventually being overcome in the afternoon. If this happens, no
severe weather ingredient will be lacking. The Gulf of Mexico will
be wide open, giving US dewpoints in the low 70s, and we will be on
the edge of an elevated cold front, which will provide lift. Sb cape
will be around 2500 j/kg across the area with 0-6 km bulk shear
around 35 kts. Therefore, storms look to form in a line near far northwest
MO along the edge of the elevated cold front. It's possible we could
see some supercellular features embedded within the line though.
The storms are expected to move southeast ahead of the surface
cold front through the entire forecast area. As for hazards, large
hail and damaging winds will be the primary concerns, but can't
rule out a tornado or two. The line should be out of the area
around midnight.

Wednesday night, the cold front will stall across northern MO
becoming more of a warm front, while an 850 mb low level jet sets
up, and upper level shortwave trough moves over the area. This will
provide the third round of storms, located mainly across northern Kansas
and MO. Hail and damaging winds can't be ruled out with this round
either. Convection will likely continue during the day Thursday as
the upper level shortwave takes its time to move through and the
warm front remains stalled across northern MO. Hail and damaging
winds will remain a concern during the day Thursday as well and we
can't rule out the tornado threat either.

Thursday night, a newly developed surface low and associated cold
front will move into the area with an upper level trough. This
will be the focus for a line of storms producing heavy rain and
possibly severe weather. The heavy rain on top of multiple rounds
of storms makes flash flooding and river flooding the main
concern. Right now, areas north of Highway 36 may get anywhere from
2-3 inches of rain, with locally higher amounts possible,
Wednesday through Friday. Areas along the I-70 corridor are
looking at potentially 1-2 inches in this time frame, with areas
well south of I-70 expecting at least 0.5 inch.

The front and storms will exit the area by Friday afternoon, drying
US out Saturday. The aforementioned front will stall though in
southern MO and will retreat back north Sunday, returning storm
chances to the area through Monday. If the front stalls further
north than expected it could introduce storm chances Saturday, but
right now all models keep rain out of our area Saturday.

&&

Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 629 am CDT Tuesday Jun 27 2017

Right now there is patchy to areas of fog across central MO and
areas along the MO river. Visibility at most of these sites is
less than 1 sm. For sites near kc, like mci and ixd, it shouldn't
drop as low. Current thinking is these sites could see
visibilities occasionally drop to around 4 sm for the next couple
of hours. For other areas, expect the fog to stick around at least
for the next few hours or so, then clearing out. VFR conditions
are expected for the rest of the period, despite storms moving
into northwest MO from the west around 06z. These storms should
stay north of I-70 and weaken as the move east across the area.
The system bringing the rain will also tighten the pressure
gradient tonight, resulting in 12 kt southerly winds across the
area after midnight. In addition, a low level jet around 850 mb
will ramp up tonight, potentially creating low level wind shear
concerns for most of the forecast area.

&&

Eax watches/warnings/advisories...
Kansas...none.
MO...none.
&&

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