000
FXUS63 KEAX 170823
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
323 AM CDT Thu Aug 17 2017

.Discussion...
Issued at 321 AM CDT THU AUG 17 2017

Rest of the Work Week (Today through Friday Night):

This morning, showers and thunderstorms are exiting the CWA. The
cold front that was the catalyst for these storms is extending along
a Unionville to MCI like as of 3AM. This front will clear through
the CWA around sunrise ushering in a much more comfortable day.
Conditions will be much less humid with dewpoints falling into the
upper 50 and lower 60s this afternoon and highs in the low to mid
80s. Tonight a quick move surface ridge of high pressure will
move through the area allowing temperatures to fall into the upper
50s and lower 60s. However, Friday morning, a upper level
shortwave will be moving from the northern Plains into the
Midwest. Storms are expected to develop along a surface trough
associated with the upper shortwave overnight Thursday and then
sag towards northwest Missouri/northeastern Kansas Friday morning.
These storms will be weakening as they do however, the
northwestern CWA mat see a few showers or isolated thunderstorms
early in the day. The surface trough will move into northern
Missouri during the late afternoon/evening and storms are again
expected to develop along it. 0-6KM shear around 40kts, steep
lapse rates, and forecast instability between 2000-2500J/Kg would
support strong to isolated severe storms with strong to damaging
winds and, marginally severe hail the main threats generally along
and west of I-35. The surface trough will then push southeast
through the CWA Friday night bringing the chance for sub-severe
storms to the rest of the CWA.

The Weekend (Saturday through Sunday night):

The weekend looks to remain dry with a warming trend. On
Saturday surface high pressure will move into the area in the wake
of the departing trough. This will lead to mostly sunny skies and
near normal highs in the mid to upper 80s. Sunday upper level
ridging will begin to build over much of the southeastern and south
central CONUS. Couple that with a return to southerly flow and highs
will rise into the uppers 80s to near 90.

The Eclipse (Monday) : SEE BELOW

Beyond the Eclipse (Tuesday to Wednesday):

Tuesday a upper level shortwave trough will move through the Great
Lakes suppressing the upper ridge southward across the area. this
will allow an associated cold front to sink into the area and bring
another round of showers and thunderstorms. Highs Tuesday are
expected to be in the mid to upper 80s. Showers and thunderstorms
will continue through Wednesday as the surface boundary will stall
across the region. Highs Wednesday will be cooler in the low to mid
80s.

&&

.Specifics for the Total Solar Eclipse on August 21st...
Issued at 321 AM CDT THU AUG 17 2017

Monday 8/21 continues to be the most difficult day in the forecast
package to make a definitive forecast. Models continue to advertise
upper level ridging over the southeastern and south central CONUS
which would suggest warm temperatures with highs in the upper 80s to
near 90. However, cloud cover and the threat for precipitation
continues to be a real concern for those planning to view the
eclipse. The forecast difficulty resides in the fact that the local
area will be on the northern periphery of the upper level ridge and
most models want to introduce a shortwave rounding the ridge and
moving through the area on Monday producing showers and
thunderstorms. However, model timing and placement of this
shortwave feature differs among models. The GFS, which has been the
best performer, would suggest storms along and south of the I-70
corridor across Missouri and eastern Kansas on Monday afternoon. The
Canadian model places the shortwave further north across northern
Missouri placing showers and thunderstorms there for Monday
afternoon. And lastly, the European, which has been the outlier
throughout, keeps the shortwave well west of the area and thusly,
conditions dry.

&&

.Aviation...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1136 PM CDT WED AUG 16 2017

Mid-level cloud cover will gradually dissipate during the
overnight hours and continue to thin out heading into Thursday in
the wake of a passing cold front. IFR to MVFR fog is expected to
persist at KSTJ, though a drier air mass advecting into the area
may lead to some improvement prior to sunrise. Otherwise, NW
surface winds will develop behind the frontal boundary Thursday
afternoon with clearing sky conditions expected through the end of
the forecast period.


&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&

$$

Discussion...73
Aviation...Welsh
Eclipse...73