Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/24/25

Area Forecast Discussion

National Weather Service Cleveland OH

 955 PM EST Thu Jan 23 2025

.SYNOPSIS...
A weak cold front will sweep across the area this evening followed
by high pressure building in from the south on Friday. Low pressure
will pass north of the Great Lakes on Saturday with a weak cold
front crossing the eastern Great Lakes into Sunday morning. Ridging
will build into the area later in the day on Sunday.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
945 pm update...
With this late evening near term forecast update, we made a few
more minor adjustments to the hourly POPs for the rest of
tonight. Overall, we left chance to likely POPs for several more
hours over NEOH and NWPA regarding the light to moderate snow
showers along and ahead of a front that is pushing through
the area. Most of north central and northwest Ohio is basically
done with the snow showers for tonight. There will be some
scattered lake effect or enhanced snow showers that will linger
across the snowbelt through the early morning hours.

700 pm update...
We made some minor updates to the hourly POPs from 23z through
09z this evening into the overnight to better reflect radar
trends and the latest HRRR model guidance. There has been a
slight uptick in a few of the snow showers becoming more
convective with brief bursts of heavier snow. A couple isolated
moderate to briefly heavier squalls are possible through about
10 pm or so. The rest of the forecast remains on track with no
adjustments needed at this time.

Previous discussion...
A trough is bisecting the Central Great Lakes region this
afternoon with a weak cold front moving into NW Ohio, extending
from Detroit to Defiance at 3 PM. Southwest winds have been
ongoing ahead of the trough with temperatures warming into the
20s this afternoon area wide. In addition, we have seen some
light snow moving east across the area today although is
struggling to reach the ground as it nears NW Pennsylvania due
to the very dry sub cloud air. Back to the west we expect snow
to fill in along the cold front, bringing a burst of snow to
much of the area through the evening hours. Moisture with the
front is shallow and only extends up to around 8K feet. However
given that the dendritic growth zone is also below this layer
with shallow lift ramping up along the front, we are expecting a
moderate burst of snow to fill in along the front. In addition
the snow squall parameter is indicating some potential for
squalls but neither the winds nor the drop in temperatures
indicates high end squalls. Moisture from Lake Michigan is
contributing to snow showers approaching from Indiana and will
see some contribution of moisture over Lake Erie despite the
western two thirds of the lake being mostly ice covered. The ice
is likely to reduce potential accumulations across the snowbelt
though through the overnight. In general expecting much of the
forecast area to see scattered to numerous snow showers
resulting in a half inch to an inch of snow with accumulations
of 1 to 3 inches across the snowbelt. With a west/northwest flow
this will favor upslope areas for any higher accumulations.
Lows tonight will fall back into the 8-15 degree range with the
warmer values near Lake Erie.

The upper level trough just brushes the Great Lakes overnight with
little in the way of pressure falls aloft. At the surface we will
see a ridge of high pressure expand north up the Ohio Valley on
Friday. Low level flow backs through the day on Friday with any
lingering snow showers moving offshore of Erie County during
the afternoon. Highs will be near 20 degrees but gradual
clearing across Northwest and North Central Ohio will be
welcomed. With high pressure over eastern portions of the area
on Friday night, cold conditions will continue. Many areas in
the east will see lows dip to around 5 degrees with warming
expected through the overnight as southerly winds increase.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A shortwave/weak warm front will cross the local area Saturday,
which may result in scattered snow showers at the start of the short
term period Snow accumulation should be limited to an inch or less.
There could be a decent amount of dry air in place with strong high
pressure just to the east of the area so precipitation may struggle
to reach the surface; opted for slight chance to chance (roughly 20
percent to 30 percent) PoPs during the day Saturday with slightly
higher PoPs across the snowbelt with lake enhancement Saturday
night. The surface cold front/upper trough axis will cross the CWA
on Sunday, but generally expect a relatively dry frontal passage
outside of additional lake-enhanced snow showers. Most of the
snowbelt will likely see less than an inch of snow accumulation
Saturday night into Sunday, but locally higher amounts of 1 to 3
inches are possible in the higher elevations of NE OH and NW PA.
Surface high pressure and weak ridging aloft will allow snow showers
to taper off by Sunday night.

The air mass will finally warm up a bit at the start of the weekend
with highs reaching the upper 20s to lower 30s Saturday and
overnight lows in the lower 20s Saturday night. With that being
said, it will breezy Saturday with gusts up to around 30 mph
Saturday so wind chills will be in the single digits Saturday
morning and the teens Saturday afternoon. Temperatures cool down a
bit Sunday; expect highs in the mid 20s and wind chills in the
teens with lows in the mid to upper teens.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
An upper trough will settle over the northeastern United States
Monday with a series of shortwaves pivoting across the local area
through the majority of the long term period. This will result in
periodic lake effect snow showers through the majority of the long
term period. Not seeing a ton of signs of any significant snowfall
this far out (especially if the lake continues to freeze), but will
continue to monitor and update/communicate as warranted. Gusty
southwest winds are likely during the day Monday with widespread
gusts to 30 mph and possibly as high as 40 mph are likely.

In general, a (relative) warm up is favored; many locations will
have an opportunity rise above freezing during the day Monday
throughout least Wednesday. Monday night will likely be the warmest
night of the period with lows in the low to mid (and possibly upper)
20s expected, although minimum temps will most likely return to the
teens and lower 20s Tuesday night onward.

&&

.AVIATION /00Z Friday THROUGH Tuesday/...
Conditions are mostly in the MVFR to pockets of IFR with
scattered snow showers and a couple pockets of heavier bursts
of snow moving across the region this evening. The main
aviation message for tonight will be variable conditions from
MVFR to brief IFR due to passing snow showers through about 04z.
After 04z, the light snow will be more confined for the
snowbelt and possibly impacting ERI through the overnight. Have
TEMPO groups with varying visibility reduction of 1sm to 3sm for
select TAF sites this evening. MVFR to low end MVFR ceilings
will be around tonight into Friday morning. Some gradual
improvement to VFR ceilings and scattered out of the clouds may
occur towards the end of the TAF period of later Friday
afternoon.

Ahead of the front winds will be out of the southwest at 10-15
knots with a few gusts to 22 knots possible. The wind shift to
westerly will occur this evening as the front tracks from west
to east across the area. Winds will decrease less than 10 knots
later tonight into Friday morning. Southwest winds will return
on Friday 5 to 10 knots.

Outlook...Non-VFR likely on Friday morning. Additional Non-VFR
possible in snow showers in the snowbelt Saturday night into
Sunday.

&&

.MARINE...
The Ice Advisory has expired since the coldest temperatures and most
rapid ice growth have ended, but sub-freezing temperatures through
the next several days will result in continued moderate ice growth.
Ice may shift as winds remain in the 15 to 20 knots range tonight
into early Friday, which could close shipping channels on Lake Erie.
Additional shifting is possible as winds on the lake increase over
the weekend and especially early next week.

Winds will generally be westerly/southwesterly at 10 to 15 knots
Friday, but southwesterly winds will increase to 15 to 25 knots
Saturday and Sunday. Southwest winds increase further Monday; winds
in the open waters of the eastern and central basins may reach 30
knots late Monday morning through early Monday evening.
Probabilistic guidance (DESI LREF) highlights the open waters of the
far eastern basin in a 20 to 40 percent of gales Monday, so will
need to continue to monitor the potential for gales. Expect winds to
slowly diminish below 25 knots late Monday into Tuesday.

Small Craft Advisory issuance remains suspended until further notice
for nearshore waters from Maumee Bay to Ripley NY due to extensive
ice cover.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.

&&

$$

SYNOPSIS...KEC
NEAR TERM...KEC/Griffin
SHORT TERM...Maines
LONG TERM...Maines
AVIATION...Griffin
MARINE...Maines




Area Forecast Discussion

National Weather Service Dodge City KS

 441 PM CST Thu Jan 23 2025

.KEY MESSAGES...

- Continued chilly with below normal temperatures and strong
  northwest winds Thursday.

- Much milder with warmer downslope southwest breezes Friday.

- Another cold front Friday night will bring north winds and
  cooler temperatures again Saturday.

- Southwest Kansas will remain dry through next Tuesday. A
  chance of rain and snow is evident next Wednesday.

&&

.DISCUSSION...
Issued at 1257 PM CST Thu Jan 23 2025

RAP upper air analysis this afternoon indicated an are of
400-250mb potential vorticity advection, aligned well with the
are on GLD/MRMS mosaics radar. With the 18z observation showing
light snow, and no drier a boundary layer to the south, we added
chance flurries to sections of the forecast area, especially
those areas the HREF is signaling (usually overpredicting)
lowered visibility.

Subsidence will be the directing ingredient this evening,
eliminating the cloud cover rapidly and reinforcing a surface
high spreading out of the northern and central Rockies. Winds
will drop to under 10 knots around sunset with a more westerly
turning southwesterly trajectory through most of Friday morning.
Given a subtle downsloping airmass and the full insolation
expected on Friday, temperatures are expected to bump noticeably
several degrees the the upper 40s on average. Uncertainty still
remains however as an expected range of outcomes for highs on
average a ranges about 6 degrees - Hays (44 to 51) , Garden City
(46 to 52) for examples.

The more mild for winter conditions are expected to be short
lived with the next cold front coming in Friday night. While not
a significant impact on overnight temperatures that will still
be I the teens and 20s it will again make for a noticeably
colder and cloudy Saturday afternoon where reasonably expected
range of outcomes will be between low and only mid 30s as
northeast winds between 10 and 15 mph sustain the boundary cold
advection.

Thew weekend remains under a cold regime with a warm up on
Monday back into the 40s in the afternoon. The next slight
chances (15-30%) of precipitation per the NBM model and official
forecast begins ramping up by Wednesday morning in the south
and overspreading the greater area through Wednesday evening.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 440 PM CST Thu Jan 23 2025

VFR conditions will prevail through tomorrow with decreasing
mid level clouds over the next few hours. Winds will start out
from the northwest this evening, shifting to the southwest
overnight and continuing into tomorrow.

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Russell
AVIATION...Hovorka_42




Area Forecast Discussion

National Weather Service Des Moines IA

 529 PM CST Thu Jan 23 2025

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- Skies stay clear tonight as winds switch to the south
  southwest. Wind chills will still be frigid tonight into early
  Friday morning with values in the teens below zero, primarily
  north of US Highway 20.

- Temperatures moderate during the day Friday with highs in the
  mid 20s to mid 30s. Precipitation chances Friday remain
  minimal across the area as a disturbance approaches. However,
  a few flurries are certainly not out of the question across
  the far north.

- A warming pattern will take shape to start the upcoming work
  week with highs in the 40s

&&

.DISCUSSION...
Issued at 237 PM CST Thu Jan 23 2025

Clear skies are observed across the majority of Iowa this
afternoon, with the exception of a few high based clouds across
south central portions as seen from GOES-16 Day Cloud Phase
imagery. RAP analysis data also shows a shortwave and its
associated cloud cover over central Nebraska. Any associated
cloud cover with this feature should stay well west of the area
with clear skies expected for the remainder of the afternoon and
evening hours today. While wind chills have generally improved
(especially compared to this morning`s readings), frigid
conditions still exist with values hovering near or below zero
areawide. High temperatures today will be in the mid to upper
teens with winds gradually turning from the northwest to the
south southwest as a sfc high pressure approaches from the west.
With clearing continuing into tonight and the light winds,
decent radiational cooling is likely which will lead to lows in
the single digits near or below zero. Colder readings are likely
across areas that received snow yesterday, so have decided to
lower low temperatures across mainly east central portions of
the forecast area by a degree or two below NBM guidance in
accordance with previous shift.

Despite winds remaining light tonight into early Friday morning,
wind chills will still be frigid with values in the -10 to -15
range, primarily along and north of US Highway 20. Cloud cover will
be on the increase Friday morning ahead of a mid level shortwave
which will pass primarily over central/southern Minnesota but still
fairly close to the forecast area. Southwest flow resulting from the
departing surface high and warm air advection seen at 850mb will
lead to temperatures warming back up into the mid 30s across the far
west to mid 20s over the far east where the snowpack is lingering.
As this shortwave and its associated surface boundary moves over,
some CAMs (primarily the RAP and HRRR) hint at light precipitation
across far northern areas during the afternoon and evening hours,
with some runs also hinting at some light precipitation over
southern portions of the forecast area. However, much of the
short term model guidance indicates the majority of QPF will
remain well north of the area into Minnesota, where better
kinematic forcing is observed. BUFKIT soundings also show some
level of saturation in the mid levels, but a dry layer between
700-800 mb should help limit any snowfall. A few flurries are
certainly possible with this activity, but any impacts from this
will be extremely limited. This wave will depart the area by
late Friday evening.

A slight northwesterly to nearly zonal upper air pattern moves into
the area Saturday as an upper level disturbance over the Ontario
region competes with a closed 500 mb low over the California region.
This split flow pattern results in 1000-500mb thicknesses increasing
across the Northern Plains for start of next week. This thermal
ridging results in temperatures warming up for the start of next
week with highs currently forecast in the low to mid 40s. The threat
for precipitation remains low during this warm up as no clear
signal/consensus is seen in model output.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 529 PM CST Thu Jan 23 2025

Winds shift to southwest 09 to 13z Fri and increase to over 12kt
gusts as high as 24kt aft 16 to 18z. VFR conditions expected as
mid to high level clouds approach aft 15z. Winds relax slightly
near end of period. /rev

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Castillo
AVIATION...REV/Castillo




Area Forecast Discussion

National Weather Service Marquette MI

 613 PM EST Thu Jan 23 2025

.KEY MESSAGES...

- Lake effect snow showers diminish tonight, shifting offshore
  by daybreak on Friday. Greatest snow accumulations east,
  locally up to 3 to 4 inches.

- Temperatures tonight fall to -10 to -15F interior west, but
  with light winds, wind chills will remain above cold weather
  advisory threshold of -25.

- Passing clipper systems will bring in rounds of light lake
  effect/enhanced snow through the extended period, but
  widespread significant snowfall is not expected.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 339 PM EST Thu Jan 23 2025

Water vapor imagery and RAP analysis show mid-level troffing from ne
Canada to the southern Rockies. Shortwave that passed across the
area last night is now well e of the area. That wave initiated mdt
to at times hvy nw flow LES in its wake. A second shortwave is
currently passing over the area. This wave helped to maintain the
LES thru the morning. With the forcing associated with that wave now
beginning to shift to the se of the area, LES is showing signs of
diminishing as overall reflectivities are decreasing per KMQT radar
imagery. LES bands are not well organized either. Current temps as
of 20z range from a lonely 1F at KIWD to the upper teens far s
central and e.

Sfc high pres ridge currently over the Plains will shift e tonight,
crossing Upper MI overnight thru early Fri. As a result, low-level
winds will gradually back, bringing an end to LES from s to n across
western Upper MI tonight. Last of the LES should end on the Keweenaw
before daybreak. The backing winds, enhanced by land breeze, will
result in an increase in convergence as the LES shifts northward.
So, there should be a burst of somewhat heavier snow briefly before
the LES ends. Expect additional fluffy snow accumulations of an inch
to locally 2 inches tonight over the w from Ontonagon County
northward. To the e, the LES bands will shift e and ne during the
night, also ending by daybreak. Just as over the w, land breeze
development as gradient winds slacken will yield an increase in
convergence, and this convergence will be stronger than over the w,
leading to greater snow accumulations. Expect additional snow
accumulations of 1 to locally 4 inches, greatest in eastern Alger
County, adjacent northern Schoolcraft County and northern Luce
County.

Clouds will gradually clear out from the s during the night, but
with winds in the cloud bearing layer much slower to back than the
near sfc winds, lake effect clouds and probably some flurries well
away from the main LES will likely be slow to depart tonight. Even a
short period of clear skies will allow temps to rapidly plummet, so
still favored the low end of guidance for min temps. Expect readings
of -10 to -15F interior w, ranging up to the single digits above
zero along Lake Superior far e. Winds in the coldest areas will be
light or even calm at some locations, so wind chills will not reach
criteria for a cold weather advy.

&&

.LONG TERM /FRIDAY THROUGH THURSDAY/...
Issued at 315 PM EST Thu Jan 23 2025

Anomalously strong ridging setting up over the northeast
Pacific/Gulf of Alaska on Friday with 500 mb height rises of 360 m
or more will gradually weaken through the weekend into early next
week as the ridge moves ever so slowly toward western Canada. This
mid-upper level ridging will promote downstream troughing across the
northeast portion of North America through most of next week. The
end result will be a nw flow into the Upper Great Lakes between
these large scale features with a series of mainly weak Clipper
shortwaves moving through the region from this weekend into next
week. Any system snow with these shortwaves looks to be light until
at least maybe mid to late next week. However, forcing from these
shortwaves along with associated shots of cold advection will
support bouts of light to at times moderate lake effect snow over
mainly the NW to W snow belts through the extended forecast period.
Temperatures will gradually trend warmer for the most part, from
below normal late this week, to near normal this weekend into early
next week, to above normal by the middle of next week.

After a dry, cool and breezy Friday, the next round of clipper
shortwaves arrive Friday night into Saturday bringing light snow to
possibly moderate snow to mainly northern portions of the cwa. A few
models suggest a period of moderate snow potential across the
Keweenaw on Saturday would likely come from a lake-enhanced dominant
w-e band forming across the long axis of Lake Superior under a
convergent westerly flow. CAA behind the front will keep in LES
across the W/NW snow belts into Saturday night. Will note decent
saturation through the DGZ, as well as steeper lapse rates below the
inversion that will be lifting to near 5kft behind the front; thus,
deterministic guidance showing SLRs around 20:1 seem reasonable. 6-
hourly QPF will generally be below a tenth of an inch, but higher
values up to a tenth even to a quarter-inch are possible where lake
enhancement or stronger banding can occur. So, while a widespread 1-
3in of snow is expected from Friday night through Saturday night,
some locally higher amounts are possible, potentially flirting with
advisory criteria.

A brief period of weak ridging should result in drier conditions
Sunday, before the next series of clipper shortwaves move through
next week. While there are model timing differences, the first
Clipper shortwave next week looks like it will arrive late
Monday/Monday evening pushing a surface cold front through Upper Mi
late Monday afternoon/evening. Since model QG fields suggest little
to no mid-upper level support/forcing at the time of the sfc front`s
arrival would only expect a brief burst of maybe moderate LES
accompanying the frontal passage with light N-NW wind parallel
multiband LES behind the front Mon night into Tues. Flow turns
sharply anticyclonic and strong subsidence/drying is depicted behind
the front throughout the day Tuesday, but winds with a W/NW
component may keeping some light LES in those wind belts into Tuesday
night. Majority of model and ensemble probability guidance suggests
no more than an inch or two of LES accumulation for the N-NW wind
snow belts and certainly a sub-advisory event.

Although model agreement is a bit sketchy by the middle to end of
next week, a few of the models suggest a couple more weaker clipper
systems moving through, one on Wed and another on Thu but with the
best forcing generally staying ne of Lake Superior not really
expecting anything more than light snow at this time so only have
slight chc to low chc pops in the forecast.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 613 PM EST Thu Jan 23 2025

Lingering MVFR ceilings will persist at KCMX/KIWD, but should trend
toward VFR. KIWD is expected to improve to VFR near midnight tonight
and KCMX by early Friday morning. Some light to moderate snow
showers may persist at KCMX as winds gradually become more southwest
overnight. Light snow will also linger in the vicinity at KSAW, but
should diminish this evening as conditions improve to VFR.

&&

.MARINE...
Issued at 315 PM EST Thu Jan 23 2025

Winds out of the NW continue to come in at around 15-25 kts this
evening, but back westerly at 20 kts or less tonight as a high
pressure builds across the area. For Friday into the weekend,
primarily southwest to west winds of 25-30 kts are expected but
there could be brief periods of gale gusts to 35 knots at times,
especially late Friday night (around 50% chance) and Saturday night
(around 50-80% chance) with passing clipper systems. Guidance
suggests a potential for more westerly gales Sunday evening into
Monday as the pressure gradient tightens ahead of another
approaching clipper system. As winds shift northwest behind the
clipper`s cold front Monday night into Tuesday winds will generally
die down into the 20-30 range, although a few gale gusts may be
possible immediately behind the frontal passage on Monday night over
central and eastern Lake Superior.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Winter Weather Advisory until 7 PM EST this evening for MIZ006.

Lake Superior...
  Heavy Freezing Spray Warning until 7 PM EST this evening for
     LSZ248>250-265-266.

Lake Michigan...
None.

&&

$$

SHORT TERM...Rolfson
LONG TERM...LC
AVIATION...JTP
MARINE...LC