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fxus63 keax 291909 
afdeax

Area forecast discussion
National Weather Service Kansas City/Pleasant Hill MO
209 PM CDT Mon may 29 2017

Discussion...
issued at 209 PM CDT Monday may 29 2017

Northwest flow prevailing this afternoon after a weak cold front
moved through the region earlier this morning. Off to our
northwest, a ridge of high pressure stretching from the northern
High Plains will continue to extend southeast into the lower
missoui vally overnight, yielding dry conditions and mostly clear
skies through the evening and early overnight hours. After
midnight, midlevel clouds will likely be on the increase as
residual cloud cover from weak convection over the Central High
plains begins to advect east with time. Overnight lows should fall
into the middle to upper 50s across most locations, however low
50s will be possible across far north- central and far northeast
Missouri.

Storm chances to increase once again on Tuesday as lingering
frontal boundary begins to interact with an incoming weak
shortwave trough in continued cyclonic flow aloft. Exact timing
remains in question somewhat this afternoon, but best chances for
developing storms look to arrive by early afternoon with chances
steadily decreasing into the evening with loss of daytime heating.
Before then, fcst soundings from across the region suggest weak
to moderate instability with 1000-1500 j/kg of MLCAPE currently
forecast along with moderate unidirectional shear aloft. Quick
look at the latest 12z namnest shows developing storms around
18z just northwest of the kc Metro, with activity gradually
sliding southeast through the afternoon hrs. Considering there
should be decent upward ascent through the hail growth region,
along with steep low-level lapse rates, a few storms may achieve
severe limits with low-end severe hail and a few isolated strong
wind gusts. Synoptic scale forcing associated with the incoming
shortwave combined with modest frontal convergence should be
enough to get storms going Tuesday afternoon, and pops have been
trended upwards as a result.

High pressure to temporarily build into the region early Wednesday
which will effectively stall the front just to our south once
again. Cannot rule out a few pop up shwrs/storms Wednesday
afternoon across our far southern zones, but much of our fcst area
should see dry conditions. Fcst models hint at a possible mesoscale convective system
early Thursday morning as high pressure slides east and the
stalled front begins lifting north as a warm front. As this
occurs, NAM and GFS model solutions show a weak undulation
approaching our region in northwest flow aloft, with all
indications suggesting this will be accompanied by an organized
mesoscale convective system as a low-level jet of roughly 35-40 kts continues to feed
healthy moisture advection north across the Central Plains.
Overall severe threat looks limited right now thanks to marginally
supportive deep-layer shear levels of roughly 25-35 kts, but
these values could increase in future model runs.

And looking even further beyond this, all signs point to an
continued active pattern heading towards the end of the work week
and upcoming weekend as ample moisture advection from the Gulf
interacts with the aforementioned front which should start heading
south as strong surface high pressure builds into the upper
Midwest. GFS anomaly fcsts suggest precipitable water values of 2-3 Standard
deviations above normal by the end of the week which combined with
the front and an active midlevel pattern filled with plenty of
weak disturbances; should yield several chances for rainfall
later as we head into the upcoming weekend. At least much of the
Memorial Day Holiday weekend was a good one, right?

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1229 PM CDT Monday may 29 2017

VFR conditions expected through the forecast period as high
pressure continues to build southeast over the region. Patchy
fair wx cu this afternoon will give way to mostly clear skies this
evening before midlevel clouds begin to move in towards morning.
Shwrs/storms expected to redevelop over the region tomorrow,
however the highest probabilities will occur after the forecast
valid time and as a result, will leave mention out for now.

&&

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

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