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Area forecast discussion 
National Weather Service Hastings NE
1223 am CDT Thursday Jul 30 2015

Short term...(this evening through thursday)
issued at 248 PM CDT Wednesday Jul 29 2015

Quiet weather is forecast through the short term periods. The
pattern aloft featured fairly zonal flow across the Central Plains
today between high pressure across the Southern Plains and a
trough/potent low pressure system lifting into Ontario. At the
surface...a 1023mb surface high pressure system was building
southeast from western Nebraska. A much drier airmass had settled
onto the plains with surface dps averaging in the 40s and 50s.

The surface boundary had reached southern Kansas this afternoon and this
boundary is expected to focus convection...which is expected to
remain to our south. This being said...a subtle shortwave trough
crossing our region has resulted in a fair amount of middle level cloud
cover...which is being picked up on radar. There has been an
occasional increase in reflectivity at times and will mention a
slight chance for a sprinkle but do not expect much more than that
with temperature dewpoint spread of nearly 30 degrees.

After this wave cover will decrease tonight with
temperatures averaging in the 50s to low 60s for lows which are below
normal for this time of year due to the drier air in place. Heading
into Thursday...the surface ridge axis will migrate southeast with
return flow of southerly winds setting up during the day. Warmer air
will be drawn back onto the plains as the upper ridge axis builds
north from the Southern Plains and afternoon temperatures are forecast to return
closer to seasonal normals in the upper 80s. The sref is the only
model to suggest the potential for light precipitation in our southern and
western zones for Thursday afternoon but with chances looking minimal will
only carry silent probability of precipitation at this time.

Long term...(thursday night through wednesday)
issued at 248 PM CDT Wednesday Jul 29 2015

Aloft: the transition to the new longwave pattern will be complete
by 00z/Fri. The subtropical high will be locked-in over the desert
SW through at least next Wednesday. The longwave ridge will be over the western
USA with the trough over the east. The main band of westerlies will
remain north of the forecast area. This means essentially no synoptic
forcing which leads to the typical low confidence in thunderstorm

Surface: a front will remain quasi-stationary from Iowa-SD-Mt through the
next several days. Multiple weak lows will propagate southeast down the
front. These lows and the well as leftover outflow
boundaries and will provide the foci for scattered thunderstorm activity...mostly
to the north and east of the forecast area. The past 3 runs of the ec suggest
the front will sink S into Kansas Monday as a more potent vorticity maximum dives
into the Great Lakes and lowers heights. The GFS does drop the front
into northern Kansas Tuesday...but then quickly lifts it back north as a warm front.
So there is uncertainty in the location of the front...and its
behavior will be complicated by spurious convectively-induced vorticity
maxima in the models as well as by thunderstorm outflows.

With a lack of synoptic forcing...really can't add much in the way
of daily details. Hit-or-miss thunderstorms will be possible each day...but
much of the time it will be dry. Temperatures will average near normal.


Aviation...(for the 06z kgri/kear tafs through 06z Thursday night)
issued at 1223 am CDT Thursday Jul 30 2015

Barring some rather unexpected changes...confidence remains high
in a continued very quiet 24 hours aviation-wise. Certainly
confidence in maintaining both VFR ceiling/visibility is higher
than average...and in fact anticipate fairly limited cloud cover
even in the middle-upper levels. Surface wind should prevail at/below
10kt through the period...with direction mainly averaging from the
south-southwest. As for the prospects of a rogue shower/thunderstorm
moving in during the latter half of the period...cannot say this
chance is truly "zero"...but it is certainly no more than 10
percent and thus is not worthy of taf inclusion.


Gid watches/warnings/advisories...


Short term...Fay
long term...halblaub

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