Area Forecast Discussion
Issued by NWS Dodge City, KS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KDDC 160520

Area Forecast Discussion
National Weather Service Dodge City KS
1220 AM CDT Sat Sep 16 2017

...Updated Aviation Discussion...

.SHORT TERM...(This evening through Saturday)
Issued at 332 PM CDT Fri Sep 15 2017

A vigorous vorticity maximum that was moving into southeast
Montana early this afternoon will continue moving northeast while
another deep trough digs from eastern Oregon into western Wyoming
by 12Z Saturday. Several minor upper level troughs were evident
along a plume of mid level moisture with H7 dewpoints of +2C to
+4C from southwest Texas into eastern Kansas. High based showers
and a few thunderstorms have persisted in the plume of mid level
moisture through the early afternoon hours. A minor upper level
trough evident on satellite imagery from southeast Colorado into
the Texas Panhandle may help to initiate a few thunderstorms near
a convergence zone/weak dryline from near HLC to east of LBL. A
cumulus field in this area has been growing since around 200 PM,
although the towers still are capped. The mid levels of the
atmosphere still are quite warm, and flow aloft is weak. It will
be difficult to get any organization or longevity to any
thunderstorms that do form.

The Wyoming upper level trough will lift out into the northern
Plains on Saturday, and a cold front will advance across western
Kansas during the morning hours. The boundary should extend from
northeast Kansas into northwest Oklahoma by mid afternoon, and
scattered thunderstorms can be expected to develop in the frontal
zone by late afternoon. High level southwest flow around 50 kts
will provide some ventilation and shear, and steep mid level lapse
rates will exist over the boundary. There will be some potential
for high wind and hail with the more intense thunderstorms.

Temperatures tonight will be warm for this time of the year with
low level winds near 15 knots, although winds will diminish toward
morning in west central Kansas as the cold front approaches.
Saturday will be a few degrees cooler than today except in south
central Kansas, where temperatures will rise into the low to mid
90s before weak cold air advection begins.

.LONG TERM...(Saturday night through Friday)
Issued at 332 PM CDT Fri Sep 15 2017

A considerably more active flow regime will evolve next week as a
mean upper level trough digs into the western United States and
southwest flow aloft becomes established over the central part of
the country. Although there may not be a well defined connection
with tropical thunderstorm activity, an area of enhanced
thunderstorms is likely to persist for a few days near the
Maritime Continent as a westward propagating equatorial Rossby
wave interferes constructively with a weak Madden-Julian
Oscillation. Enhanced thunderstorms near the Maritime Continent
often are correlated with troughing in the western United States
and increased chances for rainfall in the central part of the
country. The global models exhibit considerable spread in
forecasting evolution of the coherent tropical signals, but there
is broad consensus that enhanced thunderstorms are likely to
propagate into the western Pacific by late September. This may
favor a split flow regime in the western United States with at
least some potential for upper level cyclones in the southern
branch of the westerlies to provide increased chances for rainfall
into the first part of October.

In the more immediate future, the cold front that progresses
through western Kansas Saturday will become stationary in northern
Oklahoma Saturday night and Sunday before weakening and waving
back north as a warm front Monday. A weak low level jet may
provide enough lift to support elevated thunderstorms in at least
south central Kansas Saturday night, although chances for
nocturnal convection look better Sunday night as an upper level
trough moves into Colorado and enhances the low level jet.
Thunderstorm chances will continue Monday as the upper level
trough propagates into Kansas. There will be outflow boundaries
and the remnants of a weak warm front in western Kansas on Monday
to provide areas of enhanced upward vertical motion.

Stratus probably will develop north of the cold front in western
Kansas Saturday night, and cloud cover will persist Sunday.
Temperatures will struggle to rise above the 70s in most areas
Sunday. Warmer air will return to western Kansas Monday. A warm
plume aloft will spread from the Rockies into the central Plains
Tuesday and should result in a return to summer-like weather with
highs in the 90s.

A vigorous upper level trough will ripple through the mean long
wave position and approach Kansas on Wednesday. A cold front
should move into western Kansas Tuesday night beneath a stout EML,
and there may be little weather with the front other than a wind
shift until it encounters richer moisture and better instability
in eastern Kansas Wednesday afternoon.

The numerical models differ in their handling of synoptic scale
details later in the week. The GFS, GEM and ESRL Reforecast models
maintain more troughing in the western United States than the
more progressive ECMWF and seem more reasonable. Southwest flow
aloft is likely to persist most of the week with an enhanced
chance for thunderstorms again Friday and Saturday, although
details are impossible to anticipate with skill that far in the


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1218 AM CDT Sat Sep 16 2017

NAM Model soundings picking up on a 50 to 55 knot low level jet
across western Kansas overnight as a southeasterly surface wind
continues near 15 knots. A surface cold front will cross western
and north central Kansas early today and based on the RAP, NAM,
and even GFS it appears that this surface boundary will move
across the Hays and Garden City areas between 12z and 15z
Saturday. The front will then continue to track southeast and
cross Dodge City and Liberal by 18z. As this front passes the
southeast winds at around 15 knots will shift to the north and
briefly increasing before falling back into the 10 to 15 knot
range by late day. Models soundings indicating moisture return to
western Kansas will be primarily in the 700 to 500mb level today
so VFR conditions are expected through early this evening.


DDC  65  88  56  82 /  20  10  20  30
GCK  61  85  53  79 /  10   0  20  30
EHA  61  86  53  80 /   0   0  10  20
LBL  63  88  58  82 /  10  10  20  30
HYS  68  80  53  76 /  20  10  30  30
P28  72  94  63  83 /  20  30  40  30




AVIATION...Burgert is the U.S. government's official web portal to all federal, state and local government web resources and services.