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Area forecast discussion 
National Weather Service Dodge City Kansas
402 am CDT Thursday Sep 18 2014

..updated long term section...

Short term...(today and tonight)
issued at 328 am CDT Thursday Sep 18 2014

Thunderstorms that developed near a frontal boundary in
northwestern Kansas Wednesday afternoon persisted in elevated
fashion while progressing into central and then eastern Kansas
overnight. After midnight, persistent low level upslope flow and
diurnal cooling resulted in low stratus development along and
north of Interstate 70. Fog developed south of the Interstate
along the southern edge of the stratus from Scott County into Lane
and Ness counties. A dense fog advisory was issued for this area
since visibilities were expected to continue to drop to below a
quarter of a mile. South of the front, the lower levels were drier
and mainly clear to partly cloudy skies prevailed.

Upper level ridging will progress eastward toward the High Plains
by this evening. The aforementioned surface front will edge
northward as a warm front this afternoon and tonight into northern
Kansas. Despite surface based cape values from 1500-3000 j/kg from
northern Ness into Trego, Ellis and rush counties late this
afternoon, it appears that given the lack of upper level support,
low level convergence will be inadequate for thunderstorms to
develop along the front. High temperatures will be in the upper
80s to lower 90s, except for some lower to middle 80s at Hays on
the cool side of the front. Fair weather can be expected tonight
as upper level ridging persists. With clear to partly cloudy
skies, temperatures should fall into the 60s, with the coolest
readings in far western Kansas.

The remnants of the tropical system that have progressed into
nm/Arizona this morning will be too far southwest to affect western
Kansas through tonight, but will be discussed in the long term

Long term...(friday through wednesday)
issued at 401 am CDT Thursday Sep 18 2014

A long wave ridge ridge will continue in the western and central
United States into next week, while a mean long wave trough will
persist in the eastern part of the country. By the middle of next
week, ridging will build in the eastern part of the United States as
an upper level trough digs toward the West Coast and the upper level
cyclone developing near 120w propagates east into the Central
Plains. There is considerable uncertainty about evolution of the
flow late next week. The GFS has suggested that a trough will dig
near 110w by 27 September for the last few runs, and the European model (ecmwf) has
begun to trend toward the GFS solution with the 00z run. Most of the
GFS ensemble members support troughing in the western part of the
country late next week, but the Gem ensemble members exhibit
tremendous spread. Confidence in how the flow will evolve late next
week is very low.

A Kelvin wave is propagating through the western hemisphere and
appears to be near 80w this morning. Otherwise, there is little
coherent signal in tropical thunderstorm activity. The numerical
models do suggest some enhancement of tropical thunderstorms later
this month in the western Indian Ocean. Relative atmospheric angular
momentum remains below climatological values, but mountain torque
has increased significantly in recent days. The flow is best
represented by phase 4 of the global wind oscillation phase space
diagram, which correlates to anticyclonic flow in the western United
States. However, atmospheric angular momentum has been increasing in
around 30-40 degrees north, and a wave break in the western part of
the country certainly is possible.

In the shorter term, the remnants of Hurricane Odile near the
Arizona/New Mexico border will continue moving east and will be near
100w by Saturday morning. The European model (ecmwf) is farther south with the
tropical cyclone remnant than the GFS and seems more reasonable
given the vigorous upper level trough that will be digging into the
northern plains Saturday and the mean upper level ridge axis from
New Mexico into Wyoming. As such, heaviest rainfall likely will fall
near the Oklahoma border with lesser amounts north of Highway 50.
Rain with embedded thunderstorms should move into southwest Kansas
Friday afternoon, and widespread rainfall can be expected Friday
night into Saturday morning with the tropical system. A wind shift
will move into western Kansas Saturday as the upper level trough
digs into Minnesota, but most of the cold air will remain well to
the east of western Kansas. Weak convergence along the boundary in
the rich tropical moisture should support development of
additional showers and thunderstorms Saturday.

Some cooler air will slosh into western Kansas Sunday with upslope
flow. Widespread stratus and possibly some drizzle can be expected
Saturday night into Sunday, especially in far western Kansas. Drier
air will spread into central Kansas Sunday, but low level moisture
will continue to feed into the High Plains on the west side of the
surface high in the Midwest. The upper level trough near 120w early
this morning will approach the Central Plains by Monday night and
wallow slowly across the central part of the country through middle
week. Scattered showers and thunderstorms can be expected until the
upper level trough finally lifts out to the northeast about Thursday.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1254 am CDT Thursday Sep 18 2014

Low level upslope flow will persist over western Kansas overnight
on the north side of a nearly stationary front. This will
eventually result in the devlopment of LIFR ceilings and fog between
11-14z at khys. If the front sags south a little, then even kddc
and kgck could experience dense fog by 12z.


Preliminary point temps/pops...
ddc 92 65 88 66 / 0 0 30 80
gck 92 62 87 65 / 0 0 30 70
eha 86 61 79 61 / 0 10 80 90
lbl 89 63 86 65 / 0 0 70 90
hys 83 65 89 65 / 10 0 0 40
p28 91 67 91 69 / 10 0 30 80


Ddc watches/warnings/advisories...
dense fog advisory until 10 am CDT this morning for ksz043>046-



Short term...Finch
long term...ruthi

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