Grinnell, Kansas Weather Forecast Discussion

575
FXUS63 KGLD 030718
AFDGLD
Area Forecast Discussion
National Weather Service Goodland KS
118 AM MDT Fri Oct 3 2025
.KEY MESSAGES...
- Above normal temperatures and dry conditions will persist
  through Saturday, with highs in the upper 80s to low 90s.
- Strong southerly winds will develop across the entire area on
  Saturday. Sustained winds at 30-40 mph and gusts up to 55 mph
  will create hazardous travel conditions, especially for high
  profile vehicles on west-east routes, such as I-70, where
  cross winds will be strongest. Areas of blowing dust may
  further exacerbate travel difficulties.
- Strong southerly winds, above normal temperatures and low
  relative humidity (15-25%) will also create dangerous fire
  weather conditions on Saturday. Outdoor burning is not
  advised. Repeating, outdoor burning is not advised.
- Cooler, with normal to below normal temperatures Sunday
  through the middle portion of next week
&&
.UPDATE (TODAY THROUGH SATURDAY)...
Issued at 100 AM MDT Fri Oct 3 2025
No significant change to prior forecast reasoning and
expectations through tonight. On Saturday, deep vertical mixing
and a tightening MSLP-850 mb height gradient on the eastern
periphery of a developing/deepening lee cyclone (in advance of
an approaching upper trough) will foster strong southerly winds
across the entire area. 00 UTC 10/03 GFS forecast soundings
indicate 35-45 knot southerly flow will be present within and
throughout a ~10,000 ft mixed-layer (from the surface to ~600
mb), suggesting sustained winds on the order of 30-40 mph and
occasional gusts up to 55 mph during the afternoon and early
evening (generally prior to sunset). Wind of this magnitude will
create hazardous travel conditions, especially for high profile
vehicles on west-east routes, such as I-70, where cross winds
will be strongest. Areas of blowing dust may further exacerbate
travel difficulties. Strong southerly winds, above normal
temperatures, dry antecedent conditions and low relative
humidity (15-25%) will foster dangerous fire weather conditions
across the entire area. Outdoor burning is *not* advised on
Saturday.
&&
.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 1252 PM MDT Thu Oct 2 2025
15Z Water Vapor imagery and RAP analysis indicated broad H4
ridge across southern half of country with strong shortwave
trough moving across the ridge in the southeast US and a strong
trough continues to build off the west coast. At the surface
weak trough was noted at the surface with some residual fog
clinging to river valleys in the northeast section of the area.
Main forecast concern will be Saturday with potential for
strong winds, fire weather, thunderstorms and blowing dust.
Tonight-Friday...Little in the way of forcing for ascent
expected through the period as aforementioned ridge remains
primary weather feature across the region. While some sfc based
instability expected this afternoon, vertical moisture profiles
are very shallow and without any focusing mechanism do not see
much if any potential for any diurnally driven storms today.
Only real sensible weather concern for the overnight hours will
be potential for fog developing in the eastern fringes of the
warning area. Given the valley fog observed this morning and at
least some weak moisture advection overnight,would think similar
scenario would play out tonight. Operational models not really
pointing to this scenario, but based on expected pattern a small
chance of fog seems reasonable. Similar pattern expected today,
although winds will increase throughout the day. Some moisture
advection anticipated with persistent southeastern flow, but
with H7 thermal ridge advecting over region strong cap will
inhibit any potential thunderstorm development.
Friday night through Saturday night...Strong H5 trough will
approach the four corners region overnight, resulting in a
deepening sfc trough to the lee of the Rockies. As a result,
winds will remain breezy through the night as winds just above
the surface intensify to around 50 kts. Given the time of day
this will occur (03-06Z) I do not think there is a strong
potential for damaging wind gusts to occur overnight, but it
bears watching closely. Regardless of the maximum magnitude of
the winds overnight, breezy conditions will likely continue all
night keeping low temperatures well above climatological normals
and limiting near surface RH recovery overnight. While that
will not be a big issue during the night time, it may play a
role on Saturday afternoon and evening.
After several days of full sunshine and abundant sunshine
expected on Saturday morning combined with poor overnight
humidity recovery expect soils to be somewhat primed to be
lofted by strong winds Saturday afternoon. While confidence is
high that soils will be susceptible to being blown around,
confidence not as high in the magnitude of the winds and to a
lesser degree the fire danger threat. While last few runs of
ECMWF ensemble have several members gusting into the 50-55mph
range, the bulk of members keep gusts in the 40-45 mph range
which aligns with latest GEFS, Canadian ensemble and operational
model runs. While the trend towards lower wind speeds does tend
to lower confidence in both dust and fire weather threat,
pattern does give me concern that stronger solutions still may
be realized and do not plan on changing much in the way of
messaging until data trends solidify more. Should stronger winds
and blowing dust event materialize, most likely scenario will
be several plumes developing in afternoon and being lofted well
into the air downwind from the source, likely limiting dust
impacts to the immediate area around dust sources. Scattered
showers and thunderstorms will impact area north of Interstate
70 overnight Saturday behind cold front. Severe weather threat
is very limited and will likely occur only if storms can develop
in warm sector ahead of front where damaging winds will be the
primary threat.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 1252 PM MDT Thu Oct 2 2025
In the extended (Sunday through Thursday)...Cooler and more
unsettled conditions are anticipated through next week as colder
air becomes much more established over the area through the
start of the week. Initial cold front on Saturday night will
lower highs back down to near normal values, with a reinforcing
shot of cold air moving into the area Monday keeping highs below
normal through much of the work week. Abundant cloud cover with
front in the vicinity will like hold low temperatures up
somewhat, so as it stands it does not look like there will be a
risk of a freeze through Thursday morning. Precipitation
potential will be strongly tied to location of the front,
although given expected pattern do not anticipate much in the
way of a severe thunderstorm threat.
&&
.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1040 PM MDT Thu Oct 2 2025
GLD: VFR conditions / clear skies will rule through the TAF
period. SSE-S winds at 8-13 knots this evening and overnight
will increase to 15-25 knots during the late morning and early
afternoon (~17Z Fri). Breezy S winds will prevail throughout the
afternoon and may persist into the evening (after sunset)..
depending on the location, orientation and magnitude of the MSLP
gradient on the eastern periphery of a developing lee trough/
cyclone in Colorado.
MCK: Aside from a potential for sub-VFR fog a few hours on
either side of sunrise, ~10-15Z Friday (similar to Thu morning),
VFR conditions and clear skies will rule through the TAF
period. SE winds at 7-12 knots this evening and overnight will
increase to 12-18 knots late Fri morning. Winds will veer to the
S and increase to 15-25 knots during the early afternoon.
Breezy S winds will prevail through the remainder of the
afternoon and may persist into the evening (after sunset)..
depending on the location, orientation and magnitude of the MSLP
gradient on the eastern periphery of a developing lee trough/
cyclone in Colorado.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
UPDATE...Vincent
SHORT TERM...JRM
LONG TERM...JRM
AVIATION...Vincent

NWS GLD Office Area Forecast Discussion