Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 172053
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
353 PM CDT Sat Aug 17 2019

.SHORT TERM...(Tonight through Tuesday)
Issued at 345 PM CDT Sat Aug 17 2019

At 345 PM, a few elevated thunderstorms were ongoing over west
central Iowa. These storms should continue to drift eastward this
afternoon. Apart from this, skies were partly cloudy over our
local weather fiefdom, and surface winds were out of the south at
10 to 15 mph. Further afield, the surface front that will come
traipsing through our region tonight was generating isolated
severe storms in Black Hills and central South Dakota. A couple
severe storms (that could impact us later tonight as they move
east) were also occurring over the Front Range in Colorado.

Forecast concerns are very similar to what they were 24 hours ago,
with the focus of the forecast again being the potential for
overnight convection. Forecast soundings indicate an overnight
atmosphere supportive of potential severe convection given
appropriate forcing (mid level lapse rates near 9.0 C/km, MUCAPE
>3,000 j/kg and 40+ kt of 0 to 6 km shear). The main severe
threats overnight are damaging winds and hail, with a reduction
in the potential for flooding compared to 24 hours ago. Two main
areas of convection look to be favored overnight in the Central
Plains. The first should be along a surface cold front as it
advances eastward through the Dakotas into Nebraska, Iowa and
Minnesota. Isolated convection was already ongoing along the
front this afternoon, and is expected to grow upscale as it
shifts eastward tonight. A few of these storms could impact far
northeast Nebraska, but the greatest severe threat and storm
coverage should be over South Dakota and Minnesota. A second area
of focused thunderstorm activity is expected along the KS/NE
border, as convection over the High Plains of Colorado grows
upscale and taps an intensifying LLJ. This should result in an
MCS that tracks along the KS/NE border. Given current CAM outputs,
this could affect Nebraska Counties along and south of Interstate
80 in southeastern Nebraska between midnight and 5 AM. A corridor
of damaging winds is possible with this MCS. While not zero, the
% probability of thunderstorms is lower along a line from
Columbus to Omaha tonight. This should be especially true if a
strong MCS develops along the KS/NE border, and gobbles up some of
the energy from the LLJ. Forecaster confidence in the
location/timing of storms noted above is moderate.

A few lingering showers or thunderstorms are possible in
southeast Nebraska Sunday morning before the cold front exits the
region. Partly cloudy skies and light northerly winds should be
the norm Sunday afternoon. Afternoon high temps should range from
the upper 70s along the NE/SD border to the low 80s near the
KS/NE border. All and all not a bad end to the weekend.

Some warming is expected Monday and Tuesday as the upper level
ridge over the Southwest nudges north and east into the Central
Plains. This should push high temperatures into the 86 to 92
degree range. Uncertainty regarding the timing of our next frontal
boundary makes Tuesday`s forecast a bit tricky. Model trends over
the last 24 hours indicate a quicker arrival of the front, which
could bring more cloud cover, scattered thunderstorms and limit
high temperatures.

.LONG TERM...(Wednesday through Saturday)
Issued at 345 PM CDT Sat Aug 17 2019

Tuesday`s frontal passage should be the influencer for our weather
over the rest of the upcoming workweek. It should push high
temperatures back closer to the 80 degree mark Wednesday-Friday,
and keep light winds in place over the area as surface high
pressure sinks into the Great Lakes region. A couple thunderstorms
are possible, particularly Wednesday, otherwise the end of the
week continues to look mostly dry.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1225 PM CDT Sat Aug 17 2019

IFR conditions at KOFK should scatter out to VFR by 19z.
Otherwise, VFR conditions early in the period. There is a small
chance that showers/storms could impact KLNK/KOMA 18/05-09z. MVFR
clouds developing at all three TAF locations 18/08-14z. Could even
see a small window of LIFR at KOFK 12-15z.


&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&

$$

SHORT TERM...Albright
LONG TERM...Albright
AVIATION...DeWald


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