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Area forecast discussion 
National Weather Service Goodland Kansas
539 am MDT Friday Sep 19 2014

Update...
issued at 539 am MDT Friday Sep 19 2014

Update issued to adjust some area temperatures from latest observation. Still
have continued the mention of fog in far NE zones...especially
near McCook where still near 1sm. Rest of the forecast area will
see nice jump in temperatures as the sun rises to clear skies.

&&

Short term...(today and tonight)
issued at 243 am MDT Friday Sep 19 2014

Mainly clear skies across the forecast area this morning as region
in between high pressure to our east and Lee-side trough to our west
with a meandering warm frontal boundary over area. Little fanfare
associated with this front other than fog in northeast sections of
the County Warning Area which has been lifting northward over past several hours
with front movement. For today though expecting any remaining fog to
dissipate over the next couple of hours...aided by winds increasing
on backside of front. SW flow over the County Warning Area will give area yet
another potential day to reach near 90f in some locales...but mainly
middle to upper 80s.

Remnants of front and trough will begin to push south during the
course of day as models begin to shift upper trough out of the
northern plains towards the Great Lakes region. This will enhance the
surface gradient during the course of the day...creating the potential
for gusts to reach 35-40 miles per hour.

As the evening hours come upon the tri state region...and models
shift shortwave into the Great Lakes region...surface front draped west
across the plains will push slowly south. Initially front will push
through Nebraska overnight setting up along the Kansas/NE border towards
12z Saturday. Have included sl chance probability of precipitation for rain shower/thunderstorm through northern
half of County Warning Area...with best chances along the NE/Kansas border. Overnight
lows will range from the u50s to l60s.

Long term...(saturday through thursday)
issued at 243 am MDT Friday Sep 19 2014

Going into the start of the weekend on Saturday...surface front still
draped across northern Kansas...but will slowly push southward.
Initially with high pressure building in behind front...highest probability of precipitation
will be east...but shift to all of County Warning Area as daytime heating works into
the rain shower/thunderstorm process. Will show highest probability of precipitation for precipitation after 18z
Saturday...tapering from the north as boundary settles just south of
the area by 00z sun. Remnants of the front will linger south of the
region up into eastern Colorado. Weak 925/850mb low over the eastern
rockies...combined with east-southeast flow from surface ridge over Central
Plains...will keep enough instability to trigger some rw/trw. So
have kept sl chance probability of precipitation for sun/Sun night with best chances over
Yuma/Kit Carson/Cheyenne counties. Low may try to shift eastward
Sunday night...putting western Kansas zones near a sl chance for /rw/trw
overnight. Highs over the weekend will start in the low 80s
Saturday...down to the 70s aided by cooler air with ridge to our
north and east. Overnight lows will be in the 50s.

Modest upper level westerlies will be in place early Monday across
the Central Plains. A shortwave trough that evolves from a deep
closed low in/near California over the weekend will be encroaching
on the area by early Monday. Shortwave ridging should remain
dominate through the first part of the day but increasing forcing
aloft...strengthening Lee trough and low level convergence...and
deepening moisture will result in showers and thunderstorms late in
the day. Instability has trended upward in the last few runs with
steeper middle level lapse rates shown in GFS forecast soundings
contributing to low/moderate cape. This in combination with only
marginally favorable deep layer shear for storm organization should
limit the threat of severe thunderstorms.

The upper level pattern becomes considerably more complicated by
Tuesday and especially by Wednesday and Thursday. This is when gefs
spread becomes quite large and deterministic guidance run to run
consistency is below average. The axis of the shortwave trough
lingers over the forecast area as it elongates with most of the
energy shifting northeast. By Thursday both models show a weak
closed low forming at the base of the trough somewhere over the
southern or Central Plains...although the latest run of the European model (ecmwf)
has trended away from this. With the high uncertainty have simply
trended the consensus/consistency blend toward climatology for probability of precipitation for a
couple of periods late in the extended until medium range guidance
converges on a solution.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 539 am MDT Friday Sep 19 2014

For kgld...VFR conditions through forecast period. Sky clear mainly with
some daytime cumulus this afternoon...then high clouds from
approaching front later tonight. Wind south-southwest 10-20kts with gusts
near 30 kts by midday. After 06z...west-southwest 5-10kts. For kmck...MVFR/IFR
fog through 13z then VFR west/ mainly sky clear-few050 through 06z. After 06z
low/middle clouds approach region. Winds south-southwest 5-15 kts with gusts to 25
kts by 16z.

&&

Gld watches/warnings/advisories...
Kansas...none.
Colorado...none.
NE...none.
&&

$$

Update...jn
short term...jn
long term...jn/brb
aviation...jn

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