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809
FXUS63 KOAX 201127
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
627 AM CDT Thu Sep 20 2018

.SHORT TERM...(Today through Saturday Night)
Issued at 301 AM CDT Thu Sep 20 2018

Storms continued to fester overnight across northeast Nebraska, in an
area of warm advection, just north of a frontal boundary.  A surface
low will begin it`s trek from south-central Nebraska to northern
Iowa this morning.  This movement could bring us a break in
precipitation late this morning/early afternoon, as the warm front
is pushed further northeast. South of the front, southerly winds
will become gusty across much of eastern Nebraska and southwest
Iowa, in response to the progressing surface low. Gusts could reach
up to 35 mph at times. As the low deepens and lifts northeast, it
will drag a cold front across the region. Storms will begin to pop
up in central Nebraska along the front this afternoon, and become
more widespread across the forecast area as the boundary sweeps in
late this afternoon and evening.  A few strong to severe storms will
be possible as the front moves across, given moderate shear in
addition to a modest amount of instability. The main threats would
likely be strong winds and large hail. Brief periods of heavy
rainfall will also be possible, with PWATs around 1.50"-1.75".
Luckily this system appears to be fairly progressive, which should
curb flash flooding potential.

Showers should push out of far southeast Nebraska after midnight
tonight.  Gusty northerly winds will usher in a much cooler airmass
for Friday.  High temperatures will top out around 20 degrees below
Thursday`s highs, only reaching into the 60s by Friday afternoon.
Temperatures will moderate back into the low 70s Saturday, as
surface winds return to the south behind the departing system. Quiet
zonal flow will keep the area dry through the weekend.

.LONG TERM...(Sunday through Wednesday)
Issued at 301 AM CDT Thu Sep 20 2018

Sunday will remain dry, but warmer still.  Highs climb back into the
mid to upper 70s.  An upper level shortwave will move through the
western CONUS Sunday, as another surface low deepens east of the
Rockies.  Temperatures will remain in the 70s Monday before a cold
front associated with this feature pushes through Monday afternoon
and evening, bringing our next chance for precipitation and cooler
temperatures.  Models diverge on how long precip lingers into
Tuesday, with the ECMWF trending much wetter than the GFS, however
it does appear that cooler temperatures will likely continue through
mid week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 624 AM CDT Thu Sep 20 2018

A warm front between KLNK and KOFK this morning, lifting north in
the next few hours. LIFR ceilings at KOFK should become VFR by
14z. Otherwise, increasing southerly winds to 15 to 19 knots with
gusts up to 27 knots through the remainder of the day. Storms
develop at KOFK by 20-22z, and KLNK/KOMA 23-02z. Winds becoming
northwest behind the front by 20/20z-21/01z.

&&

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

$$

SHORT TERM...KG
LONG TERM...KG
AVIATION...DeWald