Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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725
FXUS63 KEAX 171139
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
639 AM CDT Sat Aug 17 2019

.Discussion...
Issued at 413 AM CDT SAT AUG 17 2019

Focus of the morning forecast will start by looking at the ongoing
thunderstorm activity, with attention then given to the potential
for more storms this evening which will possibly persist well
into Sunday.

Early morning radar and satellite imagery shows a broad area of
thunderstorm activity across north central and north east Kansas
stretching into northwest Missouri. These storms developed in
response to the moisture and warm air advection occurring on the
nose of a nocturnal jet, which keeps developing each night across
the Central Plains in response to shortwave troughs zipping east in
the prevailing westerlies over the Northern Plains. Current
nocturnal jet is oriented from the southwest to northeast, with its
nose over Kansas City, in an environment with precipitable water
values around 2 inches. Available CAPE for the nocturnal storms
looks to be over 2000+ J/KG in eastern Kansas, as measured from
MUCAPE values, but there is a sharp gradient of instability as you
move into central Missouri due to convection late in the day Friday.
Current expectations are that these early morning storms will
continue through sunrise, as the nocturnal jet isn`t going anywhere;
with activity slowly spreading east. Expect any concerns for severe
thunderstorms to be limited to gusty winds, and marginally severe
sized hail as the storms collapse early this morning. However, while
the severe threat is diminishing, the threat of flash flooding will
persist till the storms are over later this morning. Thus, we will
keep the Flash Flood Watch going for now.

For this afternoon and this evening, we will be watching for another
round of storms as the low level jet starts to strengthen ahead of a
broad synoptic level trough axis that will sweep east through the
Rocky`s today and Sunday. However, the nose of the developing jet
will be to our north by tonight, across Nebraska and Iowa, which
will likely leave the focus for the strongest storms with the
heaviest rain across areas of far northern Missouri and points
north. And, with precipitable water values expected around 1.75
inches, we do expect more efficient rain making storms. Given the
high instability advertised for later today along the Kansas-Missouri
state line, and 0-6KM shear values of 30 to 40 knots, large hail and
damaging winds will be possible with these storms again tonight.
Additionally, any storm activity tonight may linger well into Sunday
morning, before the western trough driving said activity sweeps east
across the northern Plains.

Sunday afternoon and evening, will see the fading potential for one
last round of storms start to bubble up Sunday afternoon through
Sunday night, across central and northern Missouri. However,
confidence on this late weekend round of storms is rather low as it
will be dependent on where a surface high will be and the
development of an over running jet on the backside of an exiting
synoptic level trough.

Beginning of the work week...looks hot and humid. Moisture left form
this weekends rain will readily evaporate as temperatures climb
back into the low 90s both Monday and Tuesday. This may result in
heat indices around 105 degrees to start the work week.

&&

.Aviation...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 639 AM CDT SAT AUG 17 2019

Ongoing storms across the Kansas-Missouri state line will persist
for a couple hours past the onset of this TAF cycle. After that
CIGs and VIS will improve, but another round of storms will be
likely this evening.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...Flash Flood Watch until 1 PM CDT this afternoon for KSZ025-057-
     102>105.

MO...Flash Flood Watch until 1 PM CDT this afternoon for MOZ001>008-
     011>017-020>025-028>033-037>040-043>046.

&&

$$

Discussion...Cutter
Aviation...Cutter



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