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Area forecast discussion 
National Weather Service Hastings NE
1259 PM CDT Tue Oct 25 2016

issued at 1258 PM CDT Tue Oct 25 2016

Overall am not expecting much in the way of shwr/tstm activity.
Should be very hit or miss. And there is no chance west of Hwy 183.

Higher dwpts were advecting into the region. A modest moist
tongue of dwpts (upr 50s-low 60s) was over ern Kansas and was lifting
north ahead of the sfc trof that was just west of the fcst area.

The main problem with tstm potential is the lack of decent
moisture and the eml overhead (cap).

Temps east of Hwy 281 will be 75-80f with dwpts 60-63f. With mid-
lvl lapse rates 8c/km...that will result in MLCAPE of 1500 j/kg.
That is more than sufficient for svr tstms. 0-6 km shear of 25-30
kts will favor multi-cell storm structures. However...main concern
is "if" tstms develop at all. Believe they will be few and far
between...and it may not even occur until after 6 PM.

The "best" chance will be from ern neb into cntrl Kansas...just east and
S of the fcst area.

We may add a few more details with final afd issuance for this
shift as we watch trends unfold.


Short term...(today and tonight)
issued at 350 am CDT Tue Oct 25 2016

Quiet conditions remain in place across the region early this
morning, with upper air data showing low amplitude ridging
continuing to the be the primary feature. Satellite imagery shows
a shortwave disturbance off to the west, which will be a player in
our area later today. Seeing a narrow area of mostly clear skies
over portions of the area, but plenty of clouds to the west-
southwest will continue streaming in this morning. At the surface,
southeasterly winds are in place, set up between high pressure
over the Great Lakes/Midwest and low pressure through the Lee side
of The Rockies. Speeds are on the light side, generally between
5-10 miles per hour. Seeing a gradual increase in dewpoints across the area,
a trend that is expected to continue through the day today. Been a
mild night, temps at 3 am range from the mid 40s to mid 50s. Hi-
res models continue to show the potential for some fog development
near dawn, mainly in far western areas where winds are more

The main forecast concern as we get into today/tonight continues
to lie with that upper level shortwave approaching from the west.
Latest models suggest that majority of (if not all) the 12-00z
time frame will be dry. Timing between models has been in pretty
good agreement, with this disturbance cross the area late in the
day and into this evening. There has been a trend the past few
days in models pushing the better chances further east, and the
latest run is in line with that. Possible that far east-NE portions
may see some activity late in the day today, with better chances
looking to come after 00z. Models continue to show the better
chances being just off to the east of the cwa, though certainly
can't rule out our east being affected at least briefly, mainly
east of the hw 281 corridor. Ahead of the surface boundary
accompanying this disturbances, the continued southeasterly flow
will draw more moisture north, with a corridor of near 60 deg dpts
climbing into our eastern portions. Did bump up temperatures a
bit, with forecast highs ranging from the mid 60s in the north to
near 80 in the south. Models have been consistent showing
instability of 1500+ j/kg in that same area of higher dpts, with
deeper layer shear around 30kts. Thunderstorms that develop will
have the potential to be strong/severe, and eastern portions of
the County Warning Area remain the Storm Prediction Center marginal risk for today. Hail/winds would
be the primary hazards.

Some uncertainty with exactly when precip totally ends for our
cwa, with a few models showing lingering chances across far
southern areas after 06z. At this point kept the dry forecast
going. West winds will continue building in across the area
overnight, with lows expected to fall into the mid 40s to mid 50s.

Long term...(wednesday through monday)
issued at 350 am CDT Tue Oct 25 2016

Overview...this will be a warm and dry period predominately
dominated by an upper level ridge. High temperatures will often
range from 10 to 15 degrees above normal. Normal highs are
currently around 60 and we should be in the 70s most days. Low
temperatures are also likely to remain warm and despite begin late
October should be well above freezing. Halloween is currently
shaping up to be a warm one with highs in the 70s.

Wednesday through upper level ridge will be located
over the plains Wednesday through Friday with the next shortwave
crossing The Rockies by late Friday. Sunny, warm, and dry weather
will persist with highs generally in the 70s, but could see 80
across portions of north central Kansas.

Saturday and Sunday...a weak shortwave will track east across the
Dakotas Friday night into Saturday giving US a shot of slightly
cooler air. Any precipitation will remain well north of our
forecast area in closer proximity to the upper system. Highs
should still be in the mid to upper 60s and maybe even a few 70s
over north central Kansas.

Monday (halloween): this currently appears to be a warm day just
ahead of another northern plains shortwave with highs in the 70s.
Uncertainty is higher than normal given the proximity of a
possible northern plains storm system nearing the area.


Aviation...(for the 18z kgri/kear tafs through 18z wednesday)
issued at 1258 PM CDT Tue Oct 25 2016

Significant wx: wind shift to west 23z-02z but with light wind speeds.

This afternoon: VFR with increasing clouds. Scattered cumulus will form
around 4k ft and lift to 5k ft. Then patchy multi-layered clouds
will increase at or above 10k ft. Southeast winds 10-15 kts with gusts to
near 20 kts initially will diminish. Expect wind shift to west at ear
around 23z. There could be an isolated shwr or tstm distant NE or east
of both terminals. Confidence: high

Tonight: VFR decreasing clouds from W-E. Lgt mainly west winds will
become northwest after 06z. Confidence: high

Wed thru 18z: VFR. Just a couple shreds of cirrostratus possible
around 25k ft. Northwest winds increase 12-15 kts. Could see a few gusts
to 20 kts after 14z. Confidence: high


Gid watches/warnings/advisories...


short term...adp
long term...wesely

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