FXUS63 KGID 232325

Area Forecast Discussion
National Weather Service Hastings NE
625 PM CDT Sat Jun 23 2018

.SHORT TERM...(This evening through Sunday)
Issued at 314 PM CDT Sat Jun 23 2018

This appears to be an active period especially on Sunday, but
forecast models are all over the place with their solutions
limiting confidence.

This evening...Radar at 315 PM was already indicating developing
thunderstorms just northeast of our forecast area and southwest of
our forecast area. Can not rule out southwestern storms making it
into our southwestern zones over the next few hours or additional
development across our northeast later this evening. There is
sufficient shear and instability for any of these to become
marginally severe. These initial storms are generally diurnally
driven and should begin to weaken after sunset.

Tonight...We see several forecast models generating thunderstorms
as we near dawn thanks to the approaching upper trough and strong
low level jet. However, there has been rather significant
inconsistency with where these thunderstorms will develop. Many of
the 12Z mesoscale models like the NAM and variations of the WRF
wanted to generate a large thunderstorm complex over our forecast
area as we near dawn and especially into Sunday morning. However,
the 18Z NAM totally backed off of this idea and is much drier for
our area Sunday morning although the synoptic features are still
similar. The ECMWF has been the most consistent and will generally
follow the ECMWF with this forecast. Therefore, may start to see
strong thunderstorm development to the west of our forecast area,
which could move into our western areas as we near dawn.

Sunday...As mentioned above we will generally be going with the
ECMWF which has been the most consistent. This is a day we
certainly need to watch out for strong to severe thunderstorms
across the area. We could even be seeing severe thunderstorms
during the morning hours, which is fairly rare, but is possible in
this case given the elevated instability, strong wind shear, and
timing of the upper level trough. Some models show an evolution
into an MCS/QLCS with bowing line segments resulting in the
possibility of severe winds and maybe even tornadoes. Large hail
and flash flooding are also a possibility and we may need a flash
flood watch across some of our southern counties, primarily
Kansas counties, but there is just too much uncertainty in where
things will develop to issue a flash flood watch at this point in

.LONG TERM...(Sunday night through Saturday)
Issued at 314 PM CDT Sat Jun 23 2018

Sunday Night...
Thunderstorms should be exiting to our southeast
Sunday night, but we could still see a few storms in our eastern
areas during the evening hours.

Monday...There have been some questions regarding the speed at
which this trough tracks across the plains. Recent model runs
continue to move the upper system through faster and thus have the
sfc front well east of our forecast area by Monday afternoon.
However, we could still see some general thunderstorms from
afternoon heating with the 500mb low in close proximity despite
the westerly sfc winds well behind the front, but not expecting
big precipitation amounts and any storms would probably be rather

Tuesday through Friday...As we head towards the middle and end of
the work week we expect upper level ridging to develop across the
eastern United States with an upper trough over the Rockies.
This should allow heat to gradually build back into the region.
There may continue to be a few chances at thunderstorms, but
most of the upper energy will be over the Rockies and overall we
will probably start to trend a little drier. Heat index values
could be back around 100 by later in the week across southern


.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday)
Issued at 622 PM CDT Sat Jun 23 2018

Timing thunderstorm activity will be a challenge. There is a
chance that there could be some thunder in the morning hours, but
the better chance will be during the afternoon. There could be
some later in the afternoon, but will have to watch that for later




LONG TERM...Wesely
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