904
FXUS63 KGLD 281938
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
138 PM MDT Thu Aug 28 2025

.KEY MESSAGES...

- A low probability of a severe storm or two late this afternoon
  and evening in northeast Colorado, with wind the primary
  hazard.

- Areas of fog possible tonight and into Saturday morning
  possibly dense.

- Severe storm potential continues Friday and possibly Saturday.


- Little change in the pattern through the weekend with slightly
  below normal temperatures and daily chances for rain.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 1235 PM MDT Thu Aug 28 2025

Fog is slowly dissipating across the area and should be fully eroded
by the early afternoon hours with it lingering across the east the
longest. As a result of the anticipated lingering of cloud
cover across eastern portions of the area have lowered high
temperatures down into the upper 60s. Winds are forecast to
slowly veer throughout the day and become more easterly as a
surface high pressure slides to the southeast. We are again
watching for the potential for more showers and storms. First,
some spotty showers may develop and move north to south across
the area with weak vorticity maxima moving through. This
afternoon, forcing for the day is rather meager but is
characterized by a weak shortwave off of the Rockies and
interacting with the continued easterly flow resulting in weak
convergence resulting in a cluster or two of storms after 6pm MT
moving into the eastern Colorado counties. The northern most as
it moves through Yuma county should dissipate as it approaches
the NE/KS state line due to loss of forcing as it should be
mainly diurnally driven with weak cold pool properties allowing
it to continue across most if not all of Yuma county. The 2nd
cluster favoring southern Kit Carson and Cheyenne counties
should continue into Wallace and Greeley counties as isentropic
ascent is forecast to be in place. Although not the greatest set
up for severe weather there may be some severe potential as
wind shear is forecast to be around 25-30 knots; albeit little
CAPE and lapse rates around 6-6.5 c/km should help lessen the
severe threat. More likely than not wind gusts up to 60 mph
would be the main hazard followed by hail of penny to perhaps
nickel size hail.

Fog is again forecast to return this evening and overnight as
climatologically favored easterly light winds and a moist air mass
remains in place. Further to the west fog may be more transient
as winds are forecast to be around 6-10mph which should help
keep the lower portions of the atmospheric profile relatively
more mixed. The other part that may impact fog across the west
is showers and storms can persist into the night, if so then
fog will not be as much of a concern. The favored area for dense
fog at this time looks to be along and east of a Trenton to
Leoti line where the boundary layer remains recently moist from
the rains last night and winds will be the lightest.

Friday, fog may linger through the morning hours again across the
east. The main focus for the day again will be on thunderstorm
chances. A more pronounced wave co located with a surface low
across eastern Colorado is forecast to be the main source of
lift. Cloud cover is forecast to break for some instabilty to
develop currently anticipated around 1000-1500 j/kg; RRFS does
have the clouds completely breaking and higher dew points
resulting in around 2000 j/kg. Wind shear is also forecast to be
sufficient enough for some supercell potential with effective
shear progged around 35-45 knots. The biggest question is will
mid level lapse rates be steep enough to support hail as nearly
all guidance has around 6-6.5 c/km mid level lapse rates;
however there does seem to be some warm air advection which may
be able to help overcome it. Hail up to 2 inches in size looks
to be the primary threat as a noticeable dry layer in between
850-700mb via 15Z RAP soundings along with a -20C level around
25000-26000 feet would support the potential for significant
hail if a robust up draft can maintain itself. The peak time for
this threat looks to be from 3pm-8pm MT with locales west of
Trenton to Colby currently favored at this time, but may shift
if clouds dissipate quicker or hold on longer. Additional
showers and storms are then forecast to move through the area
along a weak cold front after 9pm MT. At this time not
anticipating any severe weather with this activity.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 136 PM MDT Thu Aug 28 2025

Saturday, the region is forecast to be in NW flow and slightly
cooler in wake of the cold front with highs currently forecast in
the mid to upper 70s. Surface low pressure across the northern
Plains is forecast to move southward into the forecast area leading
to another chance for showers and storms starting during the late
afternoon and possibly throughout the night for the area. Some
severe threat may be able to materialize across the area with
better CAPE than the previous days and wind shear of 30-40 knots
in place. The severe threat may be dictated by how long Friday
night`s showers and storms remain in the area and if the
atmosphere is able to recover to realize those high of CAPE
values. The surface low continues to spin and moves slowly to
the south throughout the day Sunday as well ejecting multiple
vorticity maxima through the area continuing hit and miss rain
chances especially for eastern portions of the area through the
day Sunday. Due to the proximity of the low and cooler air at
the surface and aloft would not be surprised if a couple of
funnel clouds were to form. 12Z NAM shows a 700mb jet of around
30-35 knots which if enough mixing were to occur breezy winds
may be able to be realized; would like to see some better
consistency with guidance regarding this feature before
adjusting the forecast for this. Ridging is forecast to return
to the western CONUS and with the eastern periphery of the ridge
a bit elongated to the east should help keep western portions
of the forecast area dry.

A similar pattern to Sunday is forecast to ensue into the
middle portion of the work week with off and on chances for
rain remaining across the east as the area warms into the low to
mid 80s due to the ridge continuing to amplify. Mid week; very
good consensus with ensembles of a strong cold front pushing
through the area. Main deterministic guidance varies on the
positioning, but as this appears to be of Arctic origin these
cold fronts normally end up setting up further to the west. With
this in mind would not be surprised to see high and low
temperatures end up in the lower echelon of the forecast
envelope with highs in the low 60s and overnight lows in the low
to mid 40s. At this time its hard to see if this will be a dry
front or if precipitation will form along it as guidance is all
of the place with timing. Timing again will be key and also how
much precipitation falls this week. 12Z ECMWF ensemble guidance
suggests with the members that brings the cold front through
further to the west and actually has it the coldest has the
front moving through between 18Z Wednesday and 00Z Thursday
which if soil moisture responds correctly then blowing dust may
be a concern, but it was way to early to know for certain as
this is still 5+ days out.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1057 AM MDT Thu Aug 28 2025

Stratus is forecast to hold on for the majority of this TAF
period resulting in flight category reductions. Some breaks and
lifting of the ceilings is forecast for KGLD late this afternoon
but should return quickly as the sun sets. Watching for fog
again overnight with the most likely for KMCK; KGLD could see
some but slightly stronger winds may make it be more transient
in nature. Winds are forecast to veer and become more easterly
through the day and finally more southerly by the end of the
period. If clouds can break some this afternoon some sporadic
gusts around 20 knots are possible at each terminal.

&&

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

&&

$$

SHORT TERM...Trigg
LONG TERM...Trigg
AVIATION...Trigg