FXUS63 KGID 202315

Area Forecast Discussion
National Weather Service Hastings NE
615 PM CDT Wed Sep 20 2017

.SHORT TERM...(This evening through Thursday)
Issued at 332 PM CDT Wed Sep 20 2017

It will be dry in the short term period through Thursday, but it
will not be without a forecast challenge as a red flag warning has
been hoisted for our southwestern most counties. Please see the
fire weather section at the very bottom of this product for more

We were cooler today with light winds as an area of sfc high
pressure tracked across the region. However, we do expect
southerly winds to increase throughout the morning and early
afternoon hours on Thursday with wind gusts of 25-30 mph at times
by Thursday afternoon as an area of low pressure deepens across
the high plains. These gusty south winds will help our highs climb
back to around 90 for most of south central Nebraska to the mid
90s over north central Kansas.

.LONG TERM...(Thursday night through Wednesday)
Issued at 332 PM CDT Wed Sep 20 2017

The big issue will finally be a pretty good chance for a lot of
rainfall. A significant upper trough will dig deeply across the
western CONUS all the way south to the baja of Mexico. This is one
of the most significant troughs we've seen dig across the western
United States since spring and will allow for good northward
moisture transport across the plains along with cooler
temperatures aloft and strong dynamics to generate a rather
persist area of showers and thunderstorms along and north of an
associated sfc cool front.

We could see some warm sector strong to marginally severe
thunderstorms across our far northwestern zones late Friday
afternoon, but primarily Friday evening. Overall, any warm sector
thunderstorms should be rather isolated, but will need to be
watched for severe potential should they develop. There will be
40-50 kts of deep layer shear but instability/SBCAPE values will
be more marginal. Most of the precipitation Friday into Friday
night will be along and north of the cold front northwest of our
forecast area.

Saturday through Monday...The cold front will gradually slide
further southeast little by little each day and is expected to
enter our northwestern counties by around Saturday night or early
Sunday depending on the forecast model. Most of the precipitation
will be along and behind the cold front although a small chance
for showers and thunderstorms will exist just ahead of the front
in the warm sector. Therefore, much of our forecast area may end
up being dry on Saturday and especially southeastern zones while
showers and thunderstorms may eventually work into northwestern
zones during the day on Saturday. The front will likely slowly
track across the forecast area on Sunday and Sunday night and this
is when most of the precipitation will likely fall across much of
our forecast area. This precipitation should linger into Monday
especially across southeastern zones. We do not expect much in
the way of severe weather during this period since much of the
convection will be behind the cold front where the instability is
fairly low, but can not completely rule out some isolated strong
to severe thunderstorms. Rainfall amounts for much of the forecast
area could end up between 1.5 and 3 inches and some areas,
probably favoring western zones, could see a few amounts over 3
inches. High temperatures will cool back down into the 60s and 70s
by Monday behind the front.

Tuesday...We should finally dry out across the entire forecast
area and it will be cool with highs generally in the 60s.


.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 605 PM CDT Wed Sep 20 2017

VFR conditions are expected through the period with clear skies
and good visibilities. Expect the pressure gradient to increase
across the local area tomorrow as an area of low pressure digs
across the west coast. This will result in increasing southerly
winds...with gusts to near 30 KTS...possible after 21/18Z.


Issued at 332 PM CDT Wed Sep 20 2017

Thursday afternoon and evening...South winds will increase
throughout the morning and early afternoon hours and should be
gusting upwards of 25 to 30 mph at times by Thursday afternoon. In
addition, believe that the dewpoints will fall off more than the
superblend would suggest given strong mixing across southwestern
zones all the way to 700 mb. Therefore, adjusted dewpoints
downward based on this deep mixing that should bring some drier
air aloft down to the sfc.


NE...Red Flag Warning from 2 PM to 8 PM CDT Thursday for NEZ082.

KS...Red Flag Warning from 2 PM to 8 PM CDT Thursday for KSZ005-017.



LONG TERM...Wesely
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