640
FXUS63 KDDC 291008
AFDDDC

Area Forecast Discussion
National Weather Service Dodge City KS
508 AM CDT Mon Apr 29 2024

.KEY MESSAGES...

- The Fire Risk will be on the increase Tuesday and Wednesday.

- There is a marginal risk for severe thunderstorms (<15%) late
  Tuesday east of a Larned to Coldwater line. Should storms
  develop Hail 1-2" and strong gusty winds will be the main
  hazards.

- There is a slight chance for severe thunderstorms (15-30%)
  late Wednesday east of highway 83. Hail larger than 2", strong
  damaging winds and a few tornadoes will be possible from the
  strongest storms.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 305 AM CDT Mon Apr 29 2024

Over the next 48 hours the ensembles are in good agreement and
have run to run consistency with our first in a series of upper
level troughs moving from the Pacific northwest into the
Northern Plains Tuesday. As this system moves out into the
plains a surface cold/cool front will drop south into western
Kansas and a dryline will move east into south central Kansas by
late day. West of this dryline warm and dry conditions can be
expected Tuesday afternoon with the latest NBM mean humidity
values already falling back to around 10 percent during the
afternoon. Given this and that the forecast dew point several
days out from the NBM often is too high there is little doubt
about the dry conditions. Winds on the other hand are a bit more
unclear based on the uncertainty of how far south this
cold/cool front will move into southwest Kansas before stalling
out late day. Lighter winds near this boundary will keep the
wind speed below red flag warning criteria and given the surface
boundary locations from the majority of the short term models
it appears that this front will be far enough south to keep the
winds in check across all of southwest Kansas. Still given the
high fire risk due to the low humidity outdoor burning is
discouraged.

In addition to the fire weather risk we will also be monitoring
the potential for late day convection along the dryline cold
front Tuesday evening. Once again will refer back to the
agreement of the short term models with the surface boundaries
and as a result it appears that should storms develop along the
dryline/cold front then storm development will be near or east
of Stafford, Pratt and Barber counties. Given the current small
chances (<30%) for the dryline to be as far west as Stafford,
Pratt and Barber counties will keep a mention of thunderstorms
in the forecast for several hours Tuesday evening. If convection
does develop then hail and gusty winds will be the main hazards
from these storms before they move into central Kansas.

Over the next few days a warming trend can be expected across
western Kansas. Much like yesterday the short term models are in
good agreement with temperatures rebounding back into the upper
70s to lower 80s today with even some 90s possible on Tuesday.
The NBM guidance has been playing catchup with these warm
temperatures and now they appear more reasonable now. The
current NBM forecast has highs on Tuesday 90 degrees or greater
along and south of a cold/cool front that will be moving into
southwest Kansas during the day.

As the warm air spreads east today there will be some weak
850-700mb moisture transport and weak to no cin. This will
likely give way to some increasing clouds late today but the
HREF even indicates a 10-20% chance for precipitation. Not
overly excited about this chance even given the HREF 0.01
chances late today but unable to completely rule out some virga
or sprinkles.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 305 AM CDT Mon Apr 29 2024

The ensembles midweek appear to be coming into better agreement
with the timing of the next upper trough as it moves into the
Four Corners Region Wednesday night. The largest differences
between the ensemble clusters mid to late week is the strength
of an upper level ridge that will be exiting the eastern Pacific
and moving into the western United States.

As this next upper level trough approaches the West Central
Plains mid week an area of low pressure at the surface will
deepen across eastern Colorado allowing a moist south
southeasterly flow in the lower levels to return to southwest
Kansas. All the ensemble clusters are now showing a 60-90%
chance for surface dewpoints to be >55F east of the dryline
along with 50-70% chance for 30 knots or greater shear being
present by 7pm Wednesday. Mean surface based CIN at 7pm
Wednesday was less than 100j/kg and 50-60% of the ensemble
clusters indicated 700mb temperatures near 10C. Keep in mind
that these warm 700mb temperatures are not as impressive as last
week given that highs expected on Wednesday will be in the 90s.
Despite many positive indicators from the clusters on the
chance for thunderstorms along the dryline late Wednesday there
are still a few negatives. Even with these negatives, the
possible convection along the dryline, wherever it ends up,
Wednesday evening is something that should be monitored closely.
Reason for the increased concern is that the shear may end up
being better than what the ensembles forecast given the location
of the right exit region of the upper jet and the deepening
surface low over E/SE Colorado. We will also have to monitor if
the surface winds end up being more back Wednesday evening than
what is indicated across portions of south central Kansas as the
low level jet develops. SPC outlook appears to be a good start
but do not be surprised if the west ward extent changes as we
get closer to the event and confidence improves. In addition, it
is interesting to note the CSU-MLP, although missing a few
model runs over the last few days, appears to be trending
further west with its idea of severe weather potential. The CAPE
ECMWF EFI of 0.6 to 0.7 east of Dodge City has also shifted
westward. This does not mean severe weather will occur but if we
are able to get storms then the probability for very large hail
and strong gusty winds will be possible. A few tornadoes can
not be ruled out.

West of wherever this dryline ends up by late Wednesday it is
not severe weather but fire weather which will be a concern.
Much like conditions on Tuesday it will be just as dry if not
more so and the winds are expected to be stronger than on
Tuesday given the falling surface pressures across eastern
Colorado. Latest mean ensemble chances of humidity values <20%
and wind speeds >15mph west of a Liberal to Sublette line is
>70% which is a good indicator where the potential for dangerous
fire conditions may occur. This will be monitored closely but
at this time will hold off on any type of headlines given
uncertainty that far out on where the dryline will be.

Thursday will be another day where the dryline location will be
the key to the potential for storms and severe weather. At this
time it appears that the dryline will be east of Pratt and
Medicine Lodge so currently expect the risk for severe weather
to be east of the area as the upper level trough moves across
the West Central High Plains. There will be a few more
opportunities for precipitation until the upper wave passes late
week but in addition to opportunities for precipitation a cold
frontal passage will bring some cooler, more seasonal,
temperatures briefly back to southwest Kansas. This cool down,
possibly a few tornadoes such as it is, will not last long.
Temperatures are expected to start to rebound back into the 80s
over the weekend as an upper level ridge builds east across the
Rockies and into the Central United States.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 506 AM CDT Mon Apr 29 2024

Light winds will become south at 10 to 15 knots between 15z and
18z today as a trough of low pressure at the surface begins to
develop over eastern Colorado and an area of high pressure moves
east southeast. After sunset the winds will become more
southeasterly as a low level jet at 40 to 45 knots develops
across southwest Kansas after midnight. BUFR soundings
indicating VFR conditions and tonight with the possible
exception of Liberal area. This area will need to be monitored
given that a few of the short term models are beginning to show
some +90% boundary humidity values returning as the south
southeasterly low level winds return/increase.

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Burgert