McCook, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

257
FXUS63 KGLD 021126
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
526 AM MDT Wed Apr 2 2025

.KEY MESSAGES...

- Unsettled weather pattern Thursday through Saturday with
  high chances precipitation (rain and snow) and below
  normal temperatures.

- About a 40% chance blowing snow will impact travel Saturday
  morning.

- Dry, warming trend expected to start Sunday and last into at
  least the middle of next workweek.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 436 AM MDT Wed Apr 2 2025

Overview: A highly amplified and blocked synoptic pattern..
characterized by deep, broad troughing over the western-central
CONUS.. will prevail in this period.

Today-Tonight: High-res convection allowing guidance.. and
recent radar trends.. indicate that light rain showers will
accompany the passage of a progressive upper level wave lifting
ENE across the High Plains early this morning. Rain showers are
most likely to occur along/south of Hwy 24 between ~09-15Z.
Breezy NW winds will develop late this morning and early this
afternoon as the the progressive upper wave lifts ENE-NE toward
the Upper Midwest.. and an associated mid-latitude cyclone
intensifies over eastern Nebraska and Iowa. A period of breezy
NW winds is anticipated late this morning and early this
afternoon (~15-20Z) as the MSLP-850 mb height gradient tightens
on the southwest periphery of the intensifying cyclone. Forecast
soundings via recent runs of the GFS, HRRR and RAP indicate
northwesterly low-level flow on the order of ~25-35 knots
between ~15-20Z, suggesting NW winds ~20-30 mph with gusts to
~40 mph.. depending on whether or not (and if so, to what
extent) cloud cover impedes insolation / impacts vertical
mixing. Low-level flow will rapidly weaken from south to north
during the mid to late afternoon as the intensifying cyclone
exits the region. Dry conditions will prevail this afternoon
through tonight.

Thu-Thu night: Challenging temperature and precipitation-type
forecast. Guidance continues to indicate that a compact upper
low presently situated over southern California will weaken and
stall over Arizona (today) prior to lifting NNE-NE across the
4-Corners (tonight) and Colorado (Thu).. and that an associated
lee cyclone developing over northeast New Mexico (tonight) will
meander into southwest KS (Thu) prior to weakening/dissipating
(Thu night). Virtually all model guidance indicates that this
system will produce precipitation over most or all of the Tri-
State area Thu-Thu night.. that some areas could receive locally
heavy precip (~0.50" liquid equiv).. and that a seasonably warm
airmass (characterized by 850 mb temps around 0 to 6C) will be
in place over the region prior to the development of precip. A
few common denominators persist with this system:

[1] Evaporative cooling at the onset of precipitation could
facilitate an initial p-type of wet snow or a rain/snow mix in
northeast CO late Thu morning.

[2] Even *if* snow is present at onset, strengthening low-level
warm advection on the N and NE periphery of the modest lee
cyclone advancing northward into southwest Kansas will quickly
overwhelm thermal profiles and force a transition to rain, even
in CO.

Recent 04/02 guidance indicates a later, less diurnally
favorable onset-time for precipitation and an overall `warmer`
lee cyclone evolution.. suggesting that accumulating wet snow,
if any, would likely be confined further west /higher up/ on the
Palmer Divide, i.e. west of Flagler, CO. A fairly large
temperature gradient will likely be present over the region Thu
afternoon.. when temps may range from the mid-upper 30`s
(northeast CO) to the lower 60`s (south of I-70).

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 152 AM MDT Wed Apr 2 2025

This weekend will see persistent precipitation before we dry
out for most of the next workweek.

Friday morning, we will start off with a deep trough extending
from the west Hudson Bay down to northern Baja California. This
trough will very slowly move east with the 250 mb trough axis
moving over the CWA around 6Z Sunday. This will put the High
Plains, especially the GLD CWA, under a fairly turbulent,
southwesterly flow. Down at 850 mb, an inverted trough will form
a large scale convergence zone extending from the TX/NM border
northward up through North Dakota. Over the weekend, the
convergence zone will rotate clockwise, pivoting around the
Texas Panhandle. On the eastern side, there will be substantial
moisture being funneled into the Great Plains from the Gulf via
a 30-50 kts LLJ driven by a high pressure system off the east
coast and a low over western Texas, the one driving the trough.
Over the northern Rockies, a high pressure system will descend
out of the mountains to the east, pushing cold air into the
convergence zone. As mentioned before, this system will be
moving slowly, meaning the CWA will have a very good chance of
precipitation between 12Z Friday and Saturday afternoon/evening.

We can expect the precipitation to start off as rain, and some
occasional rumbles of thunder are possible, but no severe storms
are expected. Friday afternoon into the evening hours, as the
northerly air pushes in and we lose our diurnal heating,
temperatures will likely drop into the low to mid 20s overnight,
allowing the P-type to become snow. Unfortunately, northerly
winds look to increase in intensity and 20-30 kts gusts are
forecast across the area. There is a ~40% chance winds will gust
up to 40-45 kts Saturday morning as a northerly 850 mb LLJ of
that magnitude moves into the CWA and may mix down these more
intense winds. There is about a 40-50% chance blowing snow will
impact travel and reduce visibilities down to around a mile. We
cannot rule out blizzard-like conditions, but there is not a
signal for strong forcing, meaning snowfall rates will be light
to moderate. Currently, models are highlighting locations along
and west of KS HWY 25 and south of U.S. HWY 36 to be the prime
location for impactful blowing snow between midnight and noon
Saturday morning. If this area were to expand, it would likely
expand northward and encompass Yuma county.

In the afternoon Saturday, as the inverted trough continues to
push off to the southeast out of the area, PoPs gradually
dwindle, completely exiting the area around midnight Sunday
morning. Due to the northerly winds and persistent cloud cover,
especially in the western CWA, temperatures look to remain
fairly cool, likely in the mid 30s to low 40s Saturday. If the
clouds clear out quicker and the winds weaken, temperatures
could be 5-8 degrees warmer than current predicted.

As for snow totals, there is a pretty big spread, especially in
the western CWA where the temperatures will cool the quickest.
25-75 NBM is showing a 0-7 inch spread around Burlington, CO. On
a positive note, there`s less than a 10% chance of seeing more
than 9 inches of snow, and there`s about an 80% chance for most,
if not all, of the CWA to see at least 0.2 inches of QPF!

Sunday, we will finally see the upper-level trough axis moving
past the area as a ridge builds in from the west. This will
start a dry, warming trend through the rest of the long-term. By
Tuesday or Wednesday, we could be seeing temperatures warming
back into the 70s. Low temperatures will follow a similar trend;
Monday night, will cool to around freezing, but the following
two nights look to remain above freezing. Climatologically
speaking, we are still likely to see freezing temperatures
return over the next few weeks as out average last freeze dates
are around the start of May.

List of acronyms
NBM - National Blend of Models
PoP - Probability Of Precipitation
LLJ - Low Level Jet
QPF - Quantitative Precipitation Forecast
P-type - Precipitation type
mb - Millibar
kts - Knots
Z - Zulu time (UTC)
CWA - County Warning Area
GLD - Goodland

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 520 AM MDT Wed Apr 2 2025

GLD: Aside from a potential for MVFR ceilings this morning,
mainly ~11-14Z.. VFR conditions will otherwise prevail through
the TAF period. Breezy NW winds will increase to 20-30 knots
late this morning (~15Z) and persist through early afternoon,
potentially gusting up to 35 knots, at times. Winds will
decrease to 15-25 knots during the mid-late afternoon (~22Z)..
then rapidly weaken and become light/variable around, or shortly
before, sunset this evening.

MCK: MVFR ceilings (prevailing or occasional/intermittent) are
likely until ~16Z. VFR conditions will otherwise prevail through
the TAF period. Breezy NW winds will increase to 25-30 knots
(w/gusts to ~35 knots) late this morning (~16Z) and persist
through early-mid afternoon. Winds will decrease to 15-25 knots
during the late afternoon (~22Z). Winds will further weaken and
become light/variable around sunset this evening.

&&

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

&&

$$

SHORT TERM...Vincent
LONG TERM...CA
AVIATION...Vincent