Holdrege, Nebraska 7 Day Weather Forecast

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FXUS63 KGLD 230958
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
258 AM MST Sat Nov 23 2024

.KEY MESSAGES...

- Warm weather continues through Sunday.

- Some patchy fog is possible towards sunrise this morning and
  again Sunday morning for areas along/east of Highway 83.

- Weather pattern change Sunday afternoon toward cooler
  temperatures.

- Wintry precipitation is possible for the Tri-State Area
  Wednesday into Thanksgiving Day, however details remain murky.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 216 AM MST Sat Nov 23 2024

Mid level ridging continues across the Plains along with high
clouds. For the fog potential, my confidence in it has fallen some
due to the high clouds, but there may be enough low level moisture
advection and low enough dew point depressions where some isolated
instances of it may be possible especially across Graham,Norton
and Red Willow counties but does look to favor the eastern
portions of those counties.

The remainder of the day looks to be rather uneventful with the
ridge across the area. The main story will be the above normal
temperatures with highs in the 60s across the entire area. I did
nudge temperatures up a few degrees for today as Friday
overperformed around 3-5 degrees and with 850mb temperatures
looking to warmer than Friday then the increase in temperatures
does seem to be warranted. Saturday night and into Sunday
morning looks to see another round of potential again favoring
the eastern counties but may be more coverage. Looking at upper
level RH for cloud potential there seems to be a window of
clearing starting as surface high pressure moves across the area
around 1am CT and persisting through mid morning so that did
increase my confidence as well. The variable that made me keep
the wording as patchy for now is that there isn`t any clear cut
moisture advection as it seems to be more radiational fog
potential with the light winds and clear skies.

Sunday, will see the fog across the east burn off by mid morning.
The focus will then be turning towards the next incoming cold front
which still looks to be on track moving into northern portions
of the area during the mid to later afternoon hours. Surface
high pressure and cold air advection will become more prevalent
through the the evening. RAP and NAM still do continue to show
an increase in mid level moisture from roughly 5p MT Sunday
through 1am MT Monday favoring locations along and north of
Highway 36. A concern I have for any precipitation is the push
of drier air at the surface, that it will be to dry for anything
to meaningful to make it to the ground resulting in either
nothing or flurries/sprinkles. The GFS still is more moist than
the RAP and NAM, which would favor precipitation making it to
the ground so I still can`t completely rule out that scenario so
will continue with the slight chance pops but have confined
them to 15%. Should any precipitation occur am thinking due to
the speed of the system that precipitation amounts would be
minimal. I did notice that the RAP had some negative EPV* and
theta e lapse rates of 0.5 to 1.5 which would indicate some
symmetrical instability potential leading to some isolated
higher amounts but at this time I`m thinking the chance of that
scenario playing out is around 5% since the convective potential
is not associated with the 700mb FGEN band. The other part of
the cold front to keep an eye on will be breezy wind the GFS
continues to show a 7-9mb pressure rise behind the front and the
RAP is now showing an 8-10mb pressure rise. However looking at
the 700mb and 850 mb wind field with each model the winds are
only around 30 knots maximum combined between the two. I wound
up making a higher sustained wind around 15-20 knots during the
period of the pressure rises since there isn`t much wind to work
with in the low and mid level wind fields to support higher
gusts.


Monday, high pressure will be associated across the region for the
majority of the day. This combined with 850mb temperatures of 0-2C
across the region will lead to a chilly day as highs are
currently forecasted in the low 40s. At this time it looks like
skies will be clear through the late morning and the afternoon
so we should be able to reach that high with diurnal heating. If
the the front is slower than the cloud cover associated with
the mid level moisture would lead to cooler than currently
forecasted temperatures. At this time this scenario doesn`t
appear likely to occur. Overnight low temperatures are currently
forecast to fall into the 20s overnight but should begin to
increase starting around 12am MT as the surface high moves off
to the east and some surface lee troughing develops along with
an increase of winds and winds becoming more southwesterly.

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Issued at 254 AM MST Sat Nov 23 2024

We will start the long-term in a fairly calm, zonal pattern with the
250 mb jet sitting overhead of the CWA until Wednesday. During the
first 24 hours, we can expect an 850 mb ridge axis to move east and
we will receive southerly flow Tuesday, allowing us to warm near 50.

Come Tuesday evening and lasting through the overnight hours, a jet
streak over the southern California coast is expected to create a
surge of moisture that will move across the southwestern CONUS. This
moisture will end up in the southern Great Plains by Wednesday
morning. Latest run of the models are showing the majority of this
moisture will remain well south of the CWA, likely down in Texas.
Additionally, this streak will be competing with the existing streak
over the central CONUS, likely leading to a spilt flow regime over
the High Plains. These two limiting factors are being shown in the
GFS, ECMWF, and CMC-NH and decrease PoPs across the board for the
event.

Wednesday, a heavily tilted trough extending from a low north of the
Great Lakes to northern California will push the jet stream south,
out of the CWA. As the jet transitions over and out of the CWA, we
can expect a wave or two of vorticity and an 850 mb lee low to form
in Colorado, acting as forcing mechanisms for precipitation. The
timing of this trough is the big uncertainty in the forecast and
will be the main factor for any impacts on Wednesday or Thursday.

Confidence is still low on what exactly will happen with this
system, but we are expecting a Colorado Low to form, and move
southeast into the OK/TX panhandles. The best overall chances for
precipitation will be in our Colorado counties. Ensemble members are
pretty well split between the following two scenarios, which is
causing a bimodal forecast to be reflected in the ensemble means. In
other words, there is fairly high confidence that one of two very
different scenarios will occur, but the ensemble means are
artificially creating a third scenario as a middle ground between
the two likely scenarios. This artificial third scenario is not
likely to occur and may cause confusion when looking at ensemble
mean output.

Option 1 The Dry Solution (~35-40% probability): The trough pushes
the cold front through the Great Plains early Wednesday morning and
the moisture remains south of the CWA. This would reduce our PoPs to
less then 15% across the CWA and QPF would be minimal.

Option 2 The Wet Solution (~40-45% probability): The moisture
arrives before the trough and cold front. This would greatly
increase PoPs, likely to around 60-70% for a portion of the area.
Guidance is showing that a band of precipitation is likely in this
scenario, but where this potential band will set up varies widely.
This is in addition to increased PoPs and QPF in the Colorado
counties. Locations in the banded area could see anywhere from 1-6
inches of snow with higher confidence in the 1-3 inch range.

The ending time for the precipitation ranges from late Wednesday
evening until the late morning Thursday. Regardless of which
precipitation scenario plays out, we are expecting temperatures to
cool off for Thanksgiving, aided by northwesterly winds. Current NBM
guidance suggests highs on the holiday will be in the mid 30s to low
40s. If there is snow, temperatures will lower, otherwise, they
could rise a few degrees. Overnight low temperatures will be
noticeably cooler after the system passes through, likely cooling
into the mid and upper teens Thursday night onward. This would lead
to wind chills around 5F in the western CWA Friday morning onward.

Over the weekend, guidance is hinting at another trough impacting
the area. There does not seem to be any moisture associated with
this trough, but a northwesterly 850 mb LLJ does look possible. If
this feature forms, we could see efficient CAA leading to the
coldest temperatures we`ve seen this season. We will be keeping an
eye on this system as we get closer to it.

List of acronyms:
NBM - National Blend of Models
GFS - Global Forecast System
ECMWF - European Centre for Medium-range Weather Forecasts
CMC-NH - Canadian Meteorological Centre-Northern Hemisphere
CAA - Cold Air Advection
PoP - Probability Of Precipitation
LLJ - Low Level Jet
F - Fahrenheit
QPF - Quantitative Precipitation Forecast
P-type - Precipitation type
mb - Millibar
kts - Knots
Z - Zulu time (UTC)
CWA - County Warning Area
CONUS - CONtiguous United States

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 908 PM MST Fri Nov 22 2024

For KGLD, with high pressure east of the terminal and a surface
trough developing over eastern Colorado, looking for VFR
conditions to persist during the forecast period. Winds, will be
west-southwest around 10kts, become briefly light/variable from
15z-20z, then south around 10kts.

For KMCK, with the terminal near a frontal boundary as well as
exiting high pressure, winds will remain light/variable through
about 20z Saturday then becoming southeast around 10kts. Right
now, VFR conditions are expected but will be monitoring for
some fog potential for the next forecast update at 12z
Saturday.

The visibility sensor is currently down at KMCK. Technicians
are aware of the issue. For now amendments are not scheduled
(AMD NOT SKED) for the TAF site until the sensor has been
repaired.

&&

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

&&

$$

SHORT TERM...Trigg
LONG TERM...CA
AVIATION...JN