411
FXUS63 KGLD 290451
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1051 PM MDT Sat Jun 28 2025

.KEY MESSAGES...

- Potentially severe storms are expected Sunday
  afternoon/evening, west of Highway 83. Wind gusts up to 70 MPH
  and large hail are the main threats.

- Mostly dry after Sunday with chances for storms returning
  Independence Day weekend.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 1134 AM MDT Sat Jun 28 2025

Latest upper air analysis shows the jet stream over the Northern
CONUS with an upper level short wave trough over the Central Plains.
At the surface a weak cold front extended from Eastern South Dakota
southwest across Nebraska, then extended west into Southeast
Wyoming.  A dry line over Eastern Colorado extended northeast into
Nebraska to near the cold front.  Morning satellite imagery shows
cloud development along the cold front over Nebraska into South
Dakota.

For the afternoon am expecting the cloud development to progress
southwest along the surface convergence of the cold front then the
dry line.  Despite little instability to work with, isolated
thunderstorms should start to form after 2 PM MT over Eastern CO
along the dry line as an upper level short wave trough deepens
overhead.  The dry line should not move much at all today, so any
eastward progression of storm activity will be the result of new
development along outflow boundaries, and aid from the deepening
short wave trough overhead. These storms will be similar to
yesterday, being high based around 10k ft AGL, and move slowly
unless they are riding an outflow boundary.  During the late
afternoon effective shear will increase to around 30 kts as storm
activity merges together.  For two to three hours (4pm - 7pm MT)
storms will become the most organized/intense before the environment
begins to stabilize. Nickel to quarter size hail will be the largest
size anticipated from these storms; the main threat will be wind
gusts up to 70 MPH. Straight-line winds will become more of a
threat when the storms resemble a line.

By this evening storm activity may be moving into KS and NE. However
as the storms do they will be moving out from under the upper level
short wave trough.  In addition, heating from the day will be
ending, causing the environment to become more stable. This will
cause storm activity to decline and end as the sun sets.

Most model data coming in is not showing a storm complex in
Nebraska moving south into the eastern part of the forecast area
late tonight. The upper level pattern does not seem supportive
of storm development, showing subsidence to our east.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 153 PM MDT Sat Jun 28 2025

Sunday the weak cold front will move south into the forecast area.
The front should be over the central part of the forecast area by
mid afternoon.  Behind the front moisture advection will cause dew
points to increase over the northern part of the forecast.  Despite
much more instability, confidence is on the low end of the spectrum
for storm formation behind the front due surface convergence not
being as strong as along the front.  There is an upper level short
wave trough present, but that trough looks to trigger storms more
north of the forecast area. However with effective shear around 30
kts and much more plentiful instability, storms that do form will be
better organized and more intense. Hail size may be up to two
inches for storms that form over the northern part of the
forecast area given the higher instability. Given the slow
eastward progression of storms over the northern part of the
forecast along the corridor of instability, training
thunderstorm activity may occur. If this happens, repeated
rounds of moderate to heavy rainfall may occur.

Further south, surface convergence along the "front" should aid in
storm formation late afternoon along the south and southeast
periphery of the forecast area. If storms form there they will
move out of the forecast area after only moving a short way. As
with today, the main threat will be damaging wind gusts around
70 MPH with these thunderstorms over the southeast part of the
forecast area due to the lower instability.

Sunday evening an upper level short wave trough moves across the
forecast area from the west.  This may bring a line of storms with
it.  As the storm activity moves out of CO, the activity should
shift to the central then southeast part of the forecast area
following the corridor of instability moving south behind the front.
Damaging winds around 70 MPH will continue to be the main threat
with these storms if they are in more of a line, with hail penny to
nickel size possible.

After midnight there looks to be a potential for elevated
thunderstorms as cooler air moves in and strengthens the developing
inversion.  At this time the main hazard looks to be moderate to
heavy rainfall due to effective shear being around 12 kts or so,
along with storm movement of 20 MPH or less.



Next week the weather looks dry in general until the weekend. During
the week the upper level ridge over the Southern CONUS will expand a
bit more to the north, pushing the jet stream and storm chances
further north.  This will also allow for seasonal temperatures in
the 90s.  However Monday will be the coolest day due to the passage
of the cold front the prior day.

Toward the weekend a couple stronger upper level short wave troughs
move through, pushing the jet stream slightly further south.  The
weather pattern is similar to this weekend, so while chances for
storms are better, the pattern is not all that favorable.  The
chances for rain may impact Independence Day plans.  Stay tuned for
details.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1046 PM MDT Sat Jun 28 2025

For KGLD & KMCK... VFR conditions are forecast through the
period. Storms have likely ended for the night, which will allow
skies to clear as the night goes on. Winds have become light
across most of the area. They should shift to out of the
northeast/east as the night goes on. After 15Z, winds should be
roughly from the northeast with speeds nearing 15 kts and gusts
between 20-30kts. The first chance for storms is along a
convergence boundary that is forecast to setup within the region
between 20-00Z. Chances are currently low that these storms
would move over the terminal, with the current forecast favoring
storms 2 counties south of either terminal. Be alert for
updates. Another round is then forecast to move in from the
west, similar to recent days. This line would likely move
through between 02-06Z. Either round of storms could be severe
with large hail and wind gusts around 50-55 kts.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.

&&

$$

SHORT TERM...JTL
LONG TERM...JTL
AVIATION...KAK