Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/28/24
Area Forecast Discussion
National Weather Service Goodland KS
501 PM MDT Sun Oct 27 2024
.KEY MESSAGES...
- Well above normal temperatures remain forecasted through
Tuesday. Some record highs are possible Monday and Tuesday
along with potential for record warmest minimum temperatures
on Tuesday.
- Concern for a multi-hazard day Tuesday ahead of the cold
front. Potential hazards include blowing dust, wind gusts
around 50-65 MPH, critical fire weather, and severe
thunderstorms.
- Hard freeze possible across the entire Tri-State area
Wednesday night / Thursday morning.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 200 PM MDT Sun Oct 27 2024
Across the region this afternoon, skies are mainly sunny with some
filtered sunshine in spots due to SCT-BKN high clouds moving through
the area. A weak surface trough continues to meander across the
area, allowing for mainly light/variable wind, with areas along/east
of Highway 25 starting to see sustained southerly flow, mainly ahead
of the trough. Temperatures as of 100 PM MDT are mainly in the 70s
with a few spot 60s still in portions of southwest Nebraska.
The main weather concerns for the short term period will focus on
the potential for near critical fire wx conditions to set up this
afternoon in western portions of Yuma/Kit Carson counties. On
Monday, there are near critical fire wx conditions possible in
southern portions of Greeley/Wichita counties. Tuesday will be the
big day with very windy conditions in the afternoon ahead of a cold
frontal passage. These winds could bring about blowing dust
concerns. The combination could impact area travel, especially on
west-east orientated roadways like Interstate 70.
For this afternoon and tonight, the latest HRRR continues to show
another surface trough digging south into eastern Colorado. Current
obs are starting to show the gradient starting to tighten from the
south, but the system is slow to form and push towards the CWA, due
in part from the aforementioned trough over the Highway 25 area.
Humidity values in northeast Colorado are dropping into the teens.
As winds pick up, portions of Yuma and Kit Carson counties could
still see an hour or two of near critical fire wx conditions,
especially from Flagler to just south of Yuma city.
For Monday and Monday night, the 500mb ridge currently cresting over
the central Plains/Rockies, is expected to track south and east of
the forecast area, resulting in SW flow aloft through the period. At
the surface, the trough that will build south into Colorado into
tonight persists tomorrow. A low will develop along the boundary and
slowly trek east into the CWA by the afternoon. Guidance is mixed as
to the timing/placement of the low into the area. This will result
mainly light winds area-wide except for southern portions of the CWA
south of the low. Guidance is mixed as to the extent of the gradient
that develops. Southern portions of Greeley and Wichita counties
could see some gusts approaching 20-25 mph for a couple hours.
Combined with low to mid teens for humidity over much of the area,
will create some near critical fire wx conditions mainly south of a
line from Tribune east to Leoti. No fire wx product considered at
this time. The next forecast shift may have to adjust timing/winds
if the aforementioned low track a bit further north. this could
increase the areal coverage of the affected locales. Guidance does
shift the low back towards Colorado overnight due to a blocking
ridge to the east of the area, allowing for SW flow and above normal
temperatures overnight.
Going into the Tuesday and Tuesday night timeframe, the focus shifts
back to the low over the western CWA and the front the that
develops/extends from it. Current guidance has slowed the
progression of the front through the area. The system will continue
to get a push from a strong upper low/trough from the west, but with
strong ridging from the surface to 500mb to our east, the system
will take a more slower northeast trajectory along the west side of
the ridge.
This is going to allow for much of the CWA to remain under a S/SW
flow that will tighten during the morning into the afternoon hours.
model soundings are showing inverted-v soundings in the dry airmass
ahead of the front. The potential for mixing down winds from the
850/700mb level is high. Depending on the model used, much of the
area could be seeing sustained winds in the 30-40 mph with gusts up
to 50-55 mph. Depending on the level of mixing, some locales could
see the potential of up to 60-65 mph gusts. This will be monitored
and a high wind product may be issued on the next forecast shift.
Another problem for Tuesday associated with the winds, will be the
potential for areas of blowing dust. Local research is showing this
potential w/ sustained gusts and potential mixing. For now, the best
chances (60-70%) of areas seeing these hazards will be locales
along/south of the Interstate/Highway 24. This could extend to those
locales up to the Highway 36 corridor in Kansas. Areas from there
northward into Nebraska could still see windy conditions nonetheless.
The strong winds combined with humidity in the mid and upper teens
for many areas could trigger near critical to critical fire wx
conditions. While humidity may not reach criteria, the strength of
the expected/sustained winds may warrant a potential Red Flag
Warning.
Finally for the late afternoon/evening hours, the passage of the
slow moving low/front will trigger some shower activity. Initially
in Yuma county into SW Nebraska(20%) but locales east of Highway 83
will see a 20-40% chance of rain, with some instability to warrant
some isolated thunder mainly in Norton/Graham counties. SPC does
have a marginal risk area that briefly clips Graham county, but
severe not expected. Going into Tuesday evening, the low/front
finally lifts enough north and east of the area to allow for colder
air to move into the region from the W/NW.
For temps, highs on Monday will range above normal with upper 70s
through the mid and upper 80s in some locales. Warmest areas will be
along/east of Highway 27 and along/south of the Interstate/Highway
24. Going into Tuesday, a slow moving front into the area will allow
for much of the area to see lower to mid 80s, while mainly 70s
expected in northeast Colorado into much of Dundy county in
Nebraska.
Overnight lows tonight will range from the mid 40s into the lower
50s. Warmer Monday night with a wide range from the upper 40s in the
north into the upper 50s south. Going into Tuesday night though, the
slow passage of a cold front will allow for cold air to filter into
the area from the north and west. A range in the lower to mid 30s is
expected for locales along/west of Highway 27. East of Highway 27,
upper 30s to the lower 40s expected. A few spots in Graham county
may only see the mid 40s.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 122 PM MDT Sun Oct 27 2024
Overview: Long range guidance indicates that a synoptic pattern
largely characterized by troughing /cyclonic flow aloft/ will
prevail over the western half of the CONUS through next weekend.
Wed-Thu: Guidance suggests that a cooler low-level airmass
/modest surface high pressure/ over the Northern Plains will
progress southward into the Central Plains (Wed-Wed night).. as
a pronounced upper level trough over the Rockies and High Plains
deamplifies and shifts east toward the Central/Northern
Mississippi River Valley. A modest southerly return flow regime
will follow (Thu-Thu night). Expect dry conditions and cooler
temperatures.. coolest on Wed.
Fri: Southerly return flow will strengthen.. in advance of an
amplifying upper level trough along the Pacific Coast and
Intermountain West. Expect dry conditions, warmer temperatures
and breezy south winds.
Sat-Sun: Active weather is possible this weekend.. as the
aforementioned upper trough approaches from the west. Sensible
weather conditions (wind, temperatures, cloud cover, precip
chances) will highly depend upon the evolution of the upper
trough. In this pattern, at this range.. forecast specifics
cannot be ascertained with confidence.
&&
.AVIATION /00Z MONDAY TAFS THROUGH 00Z TUESDAY/...
Issued at 457 PM MDT Sun Oct 27 2024
For KGLD & KMCK... VFR conditions are expected through the
period. LLWS is forecast tonight starting around 01-03Z as a low
level jet develops again. The jet should begin to diminish
between 09-12Z. Otherwise, near surface winds should remain from
the south, with some slight variability in direction during the
daytime hours tomorrow as a surface trough moves into the area.
&&
.CLIMATE...
Issued at 156 AM MDT Sun Oct 27 2024
October 28th High Temperature Records For ASOS Sites Within Five
Degrees of Reaching Their Record:
Goodland.....86 degrees in 2016.
Hill City....88 degrees in 1943.
October 29th Warmest Minimum (Low) Temperature Records For ASOS
Sites. A Quicker Cold Frontal Passage on Tuesday Will More Than
Likely Result In These Records Not Being Met:
Goodland.....50 degrees in 1922.
McCook.......53 degrees in 1956.
Burlington...52 degrees in 1922
Hill City....62 degrees in 1927.
October 29th High Temperature Records For ASOS Sites Within Five
Degrees of Reaching Their Record:
McCook.......87 degrees in 2003.
Hill City... 89 degrees in 1937.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
SHORT TERM...JN
LONG TERM...Vincent
AVIATION...KAK
CLIMATE...Trigg
Area Forecast Discussion
National Weather Service Salt Lake City UT
359 PM MDT Sun Oct 27 2024
.SYNOPSIS...A significant pattern change is on the way as a strong
cold front crosses the region Monday into early Tuesday, bringing
much colder temperatures and mountain snow. Snow will also impact
the Wasatch Back and Uinta County, WY. Snow showers will linger
into Wednesday.
&&
.SHORT TERM (Through 00Z Thursday)...Enjoy these last relatively
warm days, as a pattern change will bring temperatures much more
congruent with early November. Afternoon upper air and satellite
analysis indicates active southwest flow across the region. This
southwest flow is partly associated with mid to high-level
moisture from a tropical system in the eastern Pacific. Meanwhile,
an upper level low is nearly the British Columbia coast. This
upper level trough will be responsible for the significant shift
in the weather pattern across Utah Monday into Tuesday.
Occasional showers can be expected under the cloud shield
associated with the previously mentioned enhanced moisture in
southwest flow this evening into Monday morning. CAMS have become
more bullish with coverage of precipitation, particularly after
midnight tonight, especially the HRRR and the NAM NEST. If this
trend continues, the forecast may need to be updated to indicate
the potential for more widespread pre-frontal precipitation across
central and southern Utah.
Ahead of this system, gusty southwest winds are expected across
the Cedar City and Milford areas (and western Iron/Beaver
Counties) Monday afternoon and evening. Issued a wind advisory for
these locations for gusts up to 50 mph. Those with Halloween
decorations and other lightweight objects should consider moving
them inside or securing them Monday afternoon and evening.
The strong cold front will cross into far northwest Utah Monday
morning, gradually crossing the state through Monday night. As the
frontal band of precipitation reaches the Wasatch Front, broad
upper level divergence combined with the strengthening trough will
support a period of frontogenesis overhead. This signal has been
quite consistent in the majority of the guidance for several days.
Current timing of this intensification and thus moderate to heavy
precipitation looks to be somewhere between midnight Monday night
and Tuesday morning for much of the western and central portions
of the state. While valleys look to remain largely rain,
especially below 5000 feet, the Wasatch Back and Uinta County look
to change over to snow. This is likely to bring a period of
moderate to heavy snow to the mountain routes and potentially
Wasatch Back routes during the Tuesday morning rush hour.
Regardless of timing, expect to see winter driving conditions
across all mountain routes and perhaps mountain valley routes,
especially in the Park City area.
Snow may mix in at times in heavier precipitation near to above
5000 feet along the Wasatch Front and Cache Valley...but at this
time, expect minor accumulations at best.
Precipitation will gradually shift toward a more showery mode
Tuesday evening. With the upper level low overhead and relatively
steep lapse rates, expect showers to redevelop across northern
Utah Wednesday afternoon.
Lake effect/lake enhancement is always a question with cold 700mb
temperatures and relatively warm lake temperatures. With chaotic
700mb flow, it`s hard to see a concerted band developing either
Tuesday or Wednesday morning. This is evident in the University of
Utah`s lake effect guidance, which shows impacted areas ranging
from Ogden to the Skull Valley area...due to chaotic wind
direction changes through the period. Best forecast at this time
is that there will be lake enhanced showers near the Great Salt
Lake both Tuesday and Wednesday morning...but impact is likely to
be low given a low residence time in any one location and the lack
of a coherent banded feature.
Given expected snow totals and potential travel impacts, issued a
winter weather advisory for the mountains of Utah, Wasatch Back
and Uinta County, WY. Be careful out there!
.LONG TERM (After 00Z Thursday)...Shortwave ridging will build in
from the west behind an exiting storm system into Thursday. That
will bring drier conditions much of Thursday, but a trough will
track into the PacNW, which will likely bring precipitation later
Thursday. Ensembles are in good agreement on the track of the
trough through Thursday. Southwest Wyoming and Utah will be in a
southwest flow with limited forcing. Scattered valley rain and
mountain snow showers are likely for southwest Wyoming and
northern Utah, while gusty southwest winds are likely throughout
southwest Wyoming and Utah.
The trough is likely to become positively-tilted and transition
into a closed low to the southwest. That brings lower confidence
on when a cold front could track into southwest Wyoming and
northern Utah. Depending on how fast and where that happens will
be important for how strong of a cold front pushes into Utah.
Ensembles have a range from early Friday through early Saturday on
when that boundary could push through.
Once the closed low sets up to the southwest late in the week and
into the weekend, there will likely be daily rain and snow
showers, but precipitation will be relatively light for most
places with no big mountain snow accumulations likely.
&&
.AVIATION...KSLC...Clouds will decrease through the evening, with
south winds gusting around 20 knots into the morning. A
transition to northwest winds is likely around 14Z. Clouds will
increase through the day, with northwest wind gusts exceeding 20
knots after 19Z. Light rain will build after 00Z with low clouds
and likely MVFR conditions.
.REST OF UTAH AND SOUTHWEST WYOMING...Clouds will decrease into
Monday, then increase through Monday as a storm system tracks into
Utah. A boundary ahead of that storm system will bring gusty
northwest winds to northern Utah by around 19Z. Gusty southwest
winds are likely throughout southwest Wyoming and elsewhere in
Utah. Precipitation will track into the urban corridor of northern
Utah after 00Z with MVFR to IFR conditions. Precipitation will
last through much of the next day throughout Utah.
&&
.FIRE WEATHER...A cold, winter-like storm will impact the region
Monday into Wednesday. Ahead of the strong cold front, gusty
southwest winds will bring the threat of locally critical fire
weather conditions across portions of southern Utah Monday
afternoon and evening. The cold front will cross into far
northwestern Utah Monday morning, reaching southern Utah by
Monday. A band of moderate to heavy at times precipitation will
follow the front Monday night into Tuesday morning, with
precipitation shifting to a more showery mode Tuesday afternoon
into Tuesday evening. Precipitation will likely continue into
Wednesday before the storm pulls away from the area.
Temperatures will remain below normal across the majority of the
area for the remainder of the week. Another storm is possible over
the weekend, though the range of solutions make this a highly
uncertain period of the forecast.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Winter Weather Advisory from midnight Monday night to 6 AM MDT
Wednesday for UTZ108-117-125.
Winter Weather Advisory from 6 PM Monday to 6 AM MDT Wednesday
for UTZ110>113.
Wind Advisory from noon to 9 PM MDT Monday for UTZ122.
WY...Winter Weather Advisory from midnight Monday night to 6 AM MDT
Wednesday for WYZ021.
&&
$$
Kruse/Wilson
For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity