991
FXUS63 KGLD 181728
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1028 AM MST Tue Nov 18 2025

.KEY MESSAGES...

- Patchy to dense fog may impact morning travel Wednesday and
  Thursday mornings.

- Widespread rainfall, locally heavy, expected with upcoming
  storm system on Thursday and Friday.

- Another storm system moving onto the Plains early next week.

&&

.UPDATE...
Issued at 1021 AM MST Tue Nov 18 2025

An area of fairly widespread stratus has moved into northeastern
sections of the area as cooler air gradually oozes to the south.
Expecting this advance to stall somewhat as airmass to south
warms up, but in locations to the north expect much less
sunshine and overall cooler temperatures today.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 1224 AM MST Tue Nov 18 2025

This morning, we have a 500 mb low moving through the Plains,
which has lead to some radar echoes overnight, evidence of some
virga to light showers. This low, and any lingering
precipitation, will clear the area by sunrise. There is a 5%
chance of fog in the extreme northeastern CWA this morning as
the low leaves the CWA.

Later today, a weak 500 mb ridge will move over the Plains
while an 850 mb high over eastern Colorado drives more northern
air into the CWA. The northeastern CWA will only warm into the
mid to upper 50s while the southwestern CWA will warm into the
mid 60s. As the ridge axis moves over the CWA, winds will become
light and variable through the midday.

Heavier cloud cover will move in later in the day as the high
moves off to the east. The mostly cloudy skies tonight will work
to keep lows in the mid 30s. As the ridge axis clears the area,
southeasterly winds will be favored. This will lead to upslope
flow across at least the eastern half of the CWA. With RH values
nearing 100% overnight, fog is expected to start forming around
8Z in the southeastern CWA. By 12-15Z, locations east of the
Colorado border have a 50% chance of seeing at least patchy fog
and areas east of highway 83 have a 30% chance of seeing
widespread dense fog. There is a 30% chance winds will be more
southerly and prevent fog formation. Even if fog does not form,
stratus will form across most of the area.

With the surface being so saturated, there is an 80-90% chance
temperatures will stay above freezing tonight. However, on the
off chance temperatures do dip below freezing, it would likely
be the Norton county area that would cool that far. Combined
with the fog, freezing fog is a heavily impactful conditional
concern. There is a less than 5% chance freezing fog will occur,
but if it does expect very slick elevated surfaces, such as
bridges.

Fog should lift by 18Z Wednesday, aided by a low-level low
coming off the Southern Rockies. This will help keep clouds over
the eastern CWA most of the day. The western CWA will warm into
the low 60s once the clouds clear out. There`s disagreement for
highs in the eastern CWA. If the clouds stick around, which is
likely, highs will only top out in the low 50s. If the clouds
are able to clear out, low 60s will also be possible. The NBM
prefers the warmer solution, but the likelihood of the clouds
remaining puts forecaster confidence in the cooler solution.

Wednesday night, a shortwave ridge moves over the region as
winds become northeasterly, and RH values climb to near 100%.
This could lead to another night of fog, but confidence is lower
for Thursday morning fog versus Wednesday morning. Lows in the
fog prone areas look to remain in the mid 30s while the western
CWA could drop to near 30.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Issued at 225 AM MST Tue Nov 18 2025

Overview: A complex, split-flow synoptic pattern will prevail
over the Continental United States (CONUS) late this week
through early next week.

Thursday-Friday: Expect cooler temperatures, widespread cloud
cover and well above average chances for precipitation. Below
average confidence in precipitation amounts. An upper level low
located over central California at 07Z this morning will cut-
off/stall over southern CA until Wed night, when yet-another
upper low will move ashore the Pacific coast.. ejecting the
former low ENE-NE across the Desert Southwest and southern
Rockies (Thu) and TX-OK Panhandle (Thu night), where/when it
will be accompanied by a modest mid-latitude cyclone.. and, at
which point.. a strengthening southern stream jet will rapidly
transport the upper low (and associated cyclone) eastward across
the Central-Southern Plains (Fri) and Central MS River Valley
(Fri night). 00Z 11/18 operational runs of the GFS and ECMWF
continue to indicate that this system will largely (if not
entirely) be `southern-stream` in nature, in other words.. that
this system [1] will be disconnected from the northern-stream
branch of the jet and [2] unable to access (or `tap into`) a
Canadian/Arctic airmass. Southern-stream systems tend to develop
in weaker baroclinic environments.. they`re more likely to be
`limited` in terms of maturation/intensity and they`re less
likely to support wintry precipitation, especially in the
absence of a pre-existing/preceding Arctic airmass. In this
case, guidance indicates that the preceding airmass (the airmass
in place prior to the onset of precip) will be homogenous and
well-above freezing (850 mb temps 8-10C), warm enough that..
even a rate-driven transition from RA to SN would likely be out-
of-reach. Rate-driven p-type transitions (i.e. persistent heavy
precip `melting out` a saturated above-freezing thermal
profile, affecting a transition from rain to wet snow) are only
possible in the -absence- of horizontal thermal advection. In
other words, rate-driven transitions cannot occur in the
presence of -any- low-level warm advection.. a prerequisite
that, in this particular setup, is unlikely to be met. With
regard to timing, guidance presently suggests that rain would
begin a few hours on either side of sunset Thursday (~00Z Fri),
that the heaviest rain would occur between midnight and noon
(~06-18Z) Friday and that rain would rapidly abate during the
afternoon, ending altogether by sunset (~00Z Sat).

Saturday-Sunday: Below average forecast confidence*. Long range
guidance suggests that another upper level low will stall/cut-
off along the southern Pacific Coast and Desert Southwest this
weekend.. with confluent flow aloft anchored in the lee of the
central Rockies. If this is the case, expect benign weather
characterized by dry conditions, light winds and near-average
temperatures.

Sunday Night-Tuesday: Below average forecast confidence*. Rain
possible. Long range guidance is in general agreement that.. the
cut-off low over the Desert Southwest will eventually track E
or NE toward the Central or Southern Plains in this period.
Where and when, not so much.

Note: *Forecast confidence typically decreases with range.
Below average, in this context, is intended to communicate a
further reduction in confidence associated with /inherent to/
increased pattern complexity, e.g. patterns characterized by
cut-off waves and multibranched jet/wave interactions, among
others.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1021 AM MST Tue Nov 18 2025

Stratus deck moving in behind weak front will bring ceilings
down to around 2000 ft for the next few hours at MCK while
expect front to stall between KGLD and KSYF keeping clouds just
north of the GLD terminal. Expect a period of VFR conditions in
the early evening, but overall airmass hydrolapse rates
favorable for fog development by sunrise. While widespread fog
is possible, large amount of high clouds may limit cooling and
inhibit fog formation, lowering overall confidence.

&&

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

&&

$$

UPDATE...JRM
SHORT TERM...CA
LONG TERM...Vincent
AVIATION...JRM