Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/22/23
Area Forecast Discussion
National Weather Service Hastings NE
505 PM CST Thu Dec 21 2023
.KEY MESSAGES...
- Dense fog continues to be an issue for our southern and
eastern counties this afternoon. Fog is expected to linger
into the evening, with redevelopment across the area expected
tonight.
- Friday will be pleasant, with sunny skies in the afternoon,
high temperatures in the 50s and light winds.
- A slow-moving, storm system is expected to impact the region starting
this weekend and continuing through Christmas. Rain and snow
will be possible, which will cause travel impacts.
&&
.DISCUSSION...
Issued at 330 PM CST Thu Dec 21 2023
Fog continues to impact the southern and eastern portions of the
area this afternoon. The Dense Fog Advisory continues for several
counties due to continued poor visibility. Please refer to the
latest advisory product for additional information.
This afternoon, southwest flow is in place over the region, with an
upper level shortwave trough lifting to the northeast, out of the
Pueblo and Goodland CWAs. A larger system is expected to come
ashore over Southern California this evening. This system will be
something to watch, particularly for those planning on traveling
over the upcoming holiday weekend.
Rain will be possible for the area this afternoon and evening as the
shortwave moves across the region. This is not expected to be a
widespread soaking event by any means, however, areas may pick up a
few hundredths to a couple tenths of an inch of moisture. Fog will
once again be possible across the region tonight. If the HRRR and
RAP are any indication of the fog potential for tonight, areas may
once again experience dense fog tomorrow morning. Fog is not
expected to stick around quite as long tomorrow, as winds shift to
the northwest, which tends to not be as favorable for fog in our
area.
Weak ridging sets up over the InterMountain West tomorrow with
northwest flow over the Central High Plains and High Plains regions.
Friday is expected to be the nicest day of the next several, as
clouds clear out in the morning, leaving sunny to mostly sunny
skies. High temperatures will range from the low 50s in the east to
the upper 50s in the west. Winds will be fairly light, out of the
northwest in the morning, before shifting to the southwest by
evening.
Saturday, models show the system to our west becoming an open wave
as it crosses south of the Four Corners region before lifting to the
northeast Saturday evening. A few isolated showers may be possible
in the extreme western portions of Dawson, Gosper, and Furnas
counties as early as Saturday afternoon. Rain will increase in
coverage across the region Saturday evening and overnight into
Sunday. A few thunderstorms cannot be entirely ruled out Saturday
night into Sunday morning. At this point in time, severe weather is
not currently anticipated.
A deepening upper trough will continue to move across the region
Sunday into Monday, bringing chances (60-90%) for rain and snow to
the region. Considerable uncertainty remains over the exact track
of this system and any precipitation amounts. A deviation north or
south would result in a change in expected rain/snow amounts.
Additionally, timing for rain to snow transition times remains up in
the air, which also leaves snowfall amounts murky. An earlier
transition time would give us the potential for a few inches of
snow. A later transition time would result in lower snowfall
amounts. Regardless, anyone planning to travel for the Christmas
weekend will want to continue to monitor the forecast for changes,
as this storm system will result in travel impacts. Tight now, the
best chance for snow appears to be Monday into Tuesday, as cold air
pushes into the region. Expected high temperatures will range from
the mid-30s to low 40s, while overnight lows will be primarily in
the 20s and 30s.
Non-zero precipitation chances (10-20%) are possible around mid-
week, however, confidence in timing, location, and impacts is low at
this time. Expect a gradual warming trend heading into the end of
the week.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 445 PM CST Thu Dec 21 2023
IFR will have greater impacts to GRI, VS EAR tonight. GRI is
expected to drop to IFR ceilings and vis this evening. The
models have IFR lingering until tomorrow morning. A weak cold
front will move through the TAF sites which should bring in some
drier air and help scatter things out. Because of the cold
front, I am not expecting EAR to go down as hard as GRI this
evening. The models also reflect this in there solutions.
With drier air working into the region tomorrow, I would expect
VFR from mid-morning onward and decent flying conditions.
Looking ahead for my GA friends, the next round of IFR looks to
move into the area Saturday evening and low clouds look to
linger through Xmas.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Dense Fog Advisory until 7 PM CST this evening for NEZ049-064-
076-077-085>087.
KS...Dense Fog Advisory until 7 PM CST this evening for KSZ006-007-
018-019.
&&
$$
DISCUSSION...Wekesser
AVIATION...Beda
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
517 PM CST Thu Dec 21 2023
.KEY MESSAGES...
- Warm temperatures continue through Saturday.
- A strong storm system will track across the Central Plains
Saturday night, possibly through Monday night. Decent forecast
uncertainty remains with this approaching system. However, the best
chances for winter impacts at this time appear to be over western
and northwestern Nebraska. Winter hazards with this system consist
of snow, gusty winds and decent blowing snow potential.
- Temperatures will warm to above normal readings by the middle and
end of next week.
&&
.SYNOPSIS...
Issued at 308 PM CST Thu Dec 21 2023
H5 analysis this morning had a low amplitude ridge over the eastern
CONUS. This ridge extended north to the Hudson Bay of Canada. West
of this ridge, a shortwave trough extended from northeastern New
Mexico, south into far western Texas. A broad shield of cloud cover
in association with this shortwave extended from the Texas
Panhandle, north into southwestern and south central Nebraska.
Precipitation in association with this feature remained well south
of the forecast area over central and southern Kansas. West of this
shortwave, a strong closed low was approximately 400 miles of the
coast of southern California. Another feature of note this morning,
was the strong trough of low pressure over the Gulf of Alaska. As
mentioned earlier in association with the system off to the south,
abundant clouds were present over southern Nebraska this afternoon
and were having an impact on temperatures. Further north, skies were
mostly clear to partly cloudy. Temperatures as of 2 PM CT ranged
from 52 degrees at O`Neill and Broken Bow to 63 degrees at
Thedford.
&&
.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 308 PM CST Thu Dec 21 2023
A weak surface trough will migrate slowly east from central
into eastern Nebraska overnight. Initial thoughts were to
include some fog overnight in far eastern portions of the
forecast area...mainly southeastern Custer into Wheeler
counties. However, based on the latest HRRR with support from
the NAM12 this morning, thinking is the surface trough will be
just east of the forecast area by 09z Friday. Light westerly
winds on the back side of this feature will mitigate any fog
threat overnight. Look for skies to gradually clear in the south
and eastern portion of the forecast area as the shortwave
trough, currently impacting Kansas, tracks into Missouri. As for
lows tonight, with the expected light westerly winds, blended
the NBM and cooler MET guidance. This yielded forecast lows in
the middle 20s across the area. On Friday, the upper level low,
currently off the coast of southern CA, will come onshore over
northern portions of Baja California. Downstream of this
feature, weak ridging will build into the central and southern
plains. H85 temps by Friday afternoon will touch 10C in western
and southwestern Nebraska. Even with the light expected winds
and limited mixing, abundant sun will lead to highs approaching
60 in these areas. The upper level low will migrate into eastern
Arizona Friday night. Look for increasing mid and high
cloudiness to spread across the southern plains into the central
plains overnight. Increased cloudiness will lead to relatively
mild temps across the area with readings in the upper 20s to
around 30 for lows Saturday morning.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 308 PM CST Thu Dec 21 2023
The main forecast challenge in the long term deals with an
approaching southern stream upper level low and northern stream
trough of low pressure this weekend into possibly as late as
Tuesday next week. A difficult forecast is shaping up for this
system to say the least. With respect to the deterministic
models, there are two modes of thought with this system`s
evolution Saturday night into Monday night. These differences
deal with the phasing of the northern stream with the southern
stream and where this occurs geographically during the evolution
of this event. The 00z EC soln and Canadian solutions merge the
two systems over the intermountain west as early as Saturday
with the southern system becoming dominant and slowing in its
progress over Oklahoma Sunday into Monday. The latest GFS and
the NAM at 84 hours attempt to merge the systems over the
central Rockies and high plains Sunday with a stronger northern
stream presence. The US models would favor a faster soln with
fewer winter impacts to the forecast area given their faster
progression east and mid level westerlies south of the northern
stream system. The differences no doubt will lead to a limited
confidence forecast ATTM. Staying consistent with the latest EC
and GEFS ensemble probabilistic forecast, still favors the best
chances for impactful winter weather > 2 inches of snow and/or
light accumulations, over western, northwestern and portions of
north central Nebraska. If you buy into the faster NAM and GFS
solns, advisory type headlines would probably suffice over the
before mentioned areas. However, if the EC and Canadian solns do
end up verifying, there is a decent potential for warning
criteria snowfall, blowing snow and a high degree of travel
impacts to the forecast area. Right now, we will continue to
message the greatest potential winter impacts over our west,
northwest and western portions of north central Nebraska. FWIW,
the 12z EC soln, which has posted over the past hour or so, has
trended faster with its progression compared to the 00z run from
last night. It is not as progressive as the latest GFS soln,
but its forecast trend is noted. Finally, the GFS, EC (00z and
12z) and Canadian solns, lift the low into Missouri, then Iowa
or Illinois Monday night into Tuesday night. All three models
develop a decent amount of precipitation on the western
periphery of the low Monday into late Tuesday and possibly
Wednesday. Attm, the NBM soln seems to favor the EC soln which
has the low over Iowa Tuesday. This allows precipitation chances
to persist into Tuesday in the east. Beyond midweek, we should
see a warming trend back into the 40s and possibly higher.
Higher temps will hinge on the degree of snow cover resulting
from this storm system. With fairly low forecast confidence with
respect to this storm system, persons planning travel this
weekend into early next week, should closely monitor the latest
forecast and statements.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 516 PM CST Thu Dec 21 2023
Dry air aloft and near the sfc will continue across wrn Nebraska
tonight and Friday. VFR is likely in this area and the chance of
MVFR or lower flight conditions is very low, less than 20
percent.
Across ncntl Nebraska, the area of MVFR/IFR/local LIFR in low
ceilings and fog across ern Nebraska is expected to continue
moving very slowly east, away from ncntl Nebraska. Still, south
winds linger across ncntl Nebraska and there is the potential
for MVFR or lower flight conditions tonight and Friday morning.
The chance of this occurring is 20 percent.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Buttler
AVIATION...CDC
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
919 PM CST Thu Dec 21 2023
.KEY MESSAGES...
- Drizzle in far eastern MN and western WI expected tonight as
well as fog/visibility reductions across the area that could
last through the day on Friday. Widespread precipitation
Sunday and early next week.
- Much above normal temperatures will continue through the
period with records expected Sunday.
&&
.UPDATE...
Issued at 911 PM CST Thu Dec 21 2023
Forecast is more or less on track from what we had, with drizzle
starting to expand across southern MN as the saturation layer
deepens. Really, the main change to the forecast this evening
was to bump up the fog mention for western into central MN.
Although we have yet to issue any fog products, the HRRR
continues to show widespread dense fog developing over western
into central MN behind the weak elevated radar returns we are
currently seeing moving across western MN. We`ll continue to
what visibility trends, but if the HRRR ends up being anything
near reality, we would end up up with a fairly expansive dense
fog advisory for tonight into Friday morning. In addition, winds
look very weak on Friday, so we may never completely get rid of
the fog before we see it expand across the area again Friday
night. Considering our dewpoints are expected to creep up into
the low 40s on Friday, it shouldn`t be a surprise to see fog
being an issue when those dewpoints are about 15 degrees warmer
than our average highs.
&&
.DISCUSSION...
Issued at 210 PM CST Thu Dec 21 2023
Mostly cloudy skies will move in this evening as a low tracks to the
south. This will commence a period of active weather, albeit, not
the type of active December weather one would expect. Surface
moisture will increase through the day today in addition to a
continued stream of warm air advecting from the south. Highs will be
in the upper 30s and low 40s again today. This will create a good
set up for widespread fog overnight tonight. As it is the shortest
day of the year, the fog will struggle to dissipate on Friday,
creating a gloomy setup with similar temperatures to today. Drizzle
remains possible in far eastern/southeastern MN and western WI
overnight as the environment will be the most saturated there. This
being said, no accumulation is expected.
A brief period of relief from the clouds and moisture will progress
eastward on Saturday as a drier airmass makes an appearance ahead of
Sunday’s low pressure system. This will allow for partly to mostly
cloudy skies with above normal temperatures in the 40s and low 50s.
Late Saturday, the system currently responsible for dumping rain on
Southern California will progress eastward to spread the CONUS by
Sunday. While some will see snow from this system, MN/WI will likely
not be in that category as abnormally warm late December
temperatures will keep us well above freezing. As mentioned in the
former discussion, lows in the 40s for most on Saturday night are
within several degrees of record highs Sunday (granted, the records
on Sunday are in the mid to lower 40s — which is low-hanging fruit
relative to other December record highs). See the climate section
below for the records and latest projected highs.
The low to the south will contribute to what will likely be a few
days of rain across the Upper Midwest. It will linger through early
next week, allowing the warmer temperatures to remain and limit any
chances of snow through the end of 2023. Some locations could see
upwards of an inch of rain Sunday through Tuesday. However, most can
expect somewhere between 0.50”-0.75” if the ECMWF and GEFS forecasts
come to fruition. Temperatures will return back to normal on the
back side of the system as high pressure builds and weather returns
to quiet for the later half of next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 608 PM CST Thu Dec 21 2023
It`s not really a question of if, but when do cigs/vis drop to
IFR/LIFR levels tonight. With the 00z TAFs, the two main changes
were to delay the arrival of the IFR or lower cigs by a couple
of hours and also follow the HRRR & LAV with hitting the dense
fog hard for western into central MN. For MKT & MSP into WI,
moisture will be deeper, with the drizzle currently being seen
down in northern Iowa, moving up into these locations tonight.
This will keep them from going dense fog, but cigs of 500 ft or
less are still looking likely by Friday morning. With light
winds forecast for Friday, the soup and murk is expected to
stick around and be slow to improve.
KMSP...Light DZ is still expected this period given what we`re
seeing in Iowa. RAP shows DZ happening as early as 5z, though
it is most efficient at producing DZ around 12z. Given weak flow
this period, little in the way in improvements is expected
during the day on Friday.
/OUTLOOK FOR KMSP/
Sat...VFR. Chc MVFR/IFR cigs. Wind SE 5-10 kts.
Sun...MVFR/-RA likely. Wind SE 10-15 kts.
Mon...MVFR cigs likely. Chance -RA. Wind NE 10-20 kts.
&&
.CLIMATE...
Issued at 215 PM CST Thu Dec 21 2023
..December 24th Climate and Forecast..
Location Record High Forecast High
-----------------------------------------------
Twin Cities |46 (1957) | 50
St Cloud |44 (2021) | 47
Eau Claire |45 (1940) | 51
..December 25th Climate and Forecast..
Location Record High Forecast High
-----------------------------------------------
Twin Cities | 51 (1922) | 43
St Cloud | 47 (1922) | 40
Eau Claire | 45 (1994) | 45
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
UPDATE...MPG
DISCUSSION...PEM
AVIATION...MPG
CLIMATE...Dye
Area Forecast Discussion
National Weather Service Marquette MI
649 PM EST Thu Dec 21 2023
.SHORT TERM...(Through Tonight)
Issued at 237 PM EST THU DEC 21 2023
Key Messages:
-No precipitation except for light rain/drizzle over western Lake
Superior and Isle Royale early Thursday morning
GOES-16 Day Cloud Phase imagery shows stubborn, low lake effect
clouds lingering over all of the UP except Gogebic and Ontonagon
counties. RAP analysis shows 1040mb high pressure over Quebec and
1015mb troughing over the Northern Plains, which the weak pressure
gradient is allowing southerly and southeasterly winds to gradually
relax over time. Some light drizzle and flurries are coming down
this afternoon, but accumulation is unlikely. As a subtle 500mb
shortwave trough approaches the UP overnight, coverage of drizzle
and light rain showers increases over the western portions of Lake
Superior and Isle Royale, as shown in a few of the WRF members of
the 12Z HREF and to a lesser extent the NAM Nest. Measurable
precipitation is not present in the NBM through 12Z Friday until
the 90th percentile and not in a contiguous fashion until the 95th
percentile, so what precipitation falls will be of little to no
impact. Cloud cover will keep the diurnal temperature curve pretty
flat, with most NBM high temperatures today within 5-8 degrees of
tonight`s low temperatures.
.LONG TERM...(Friday through Thursday)
Issued at 200 PM EST THU DEC 21 2023
Upper air pattern consists of a split flow trough on the west coast
with a northern branch trough in the Pacific NW and a closed low off
the Baja CA coast 12z Fri. There is also a shortwave in the northern
plains 12z Fri. All three systems move east with the western ones
into the Rockies 12z Sat and into the upper Great Lakes for the
eastern one. NAM shows both western systems moving into the plains
12z Sun into 12z Mon. Drizzle and freezing drizzle are possible Fri
into Sat morning and kept them in the forecast with this event being
mostly drizzle. QPF amounts will be light. Dry and quiet Sat
afternoon into Sat night.
In the extended, the GFS and ECMWF show a deep 500 mb trough in the
southern and central plains 12z Mon with a ridge on the east coast.
Differences start immediately after that for model solutions. The
Canadian and ECMWF move the system very little 12z Tue while the GFS
moves it into the mid Mississippi Valley. By 12z Wed, the Canadian
keeps the 500 mb trough in the central plains, the ECMWF has it in
the mid Mississippi Valley and the GFS has it in the lower Great
Lakes. By 12z Thu, the GFS has the trough in New England, the ECMWF
has it in the lower Great Lakes while the Canadian is still in the
central plains. Manual sfc progs follow more of the GFS solution
with the sfc low tracking from southeast of Kansas City Missouri 12z
Mon to near Burlington Iowa 12z Tue, near Chicago 12z Wed and near
Boston 12z Thu. This track of the sfc low is further south than the
previous forecast from yesterday by a bit. Will have to still watch
this system, but appears like system slows down and warm air remains
over the area longer which would mean rain for the area.
Temperatures look to stay above normal. Still tough to say if lake
effect snow belts will have a white Christmas or not as no snow is
expected. The snow that is on the ground if it is more than 3
inches, could stay into the 25th, but less than that and it will
melt for a brown Christmas. Thinking is it will be close in a few
spots, but most areas will not have a white Christmas except in a
few places in lake effect snow belts. Temperatures look to stay
above normal for this forecast period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 631 PM EST THU DEC 21 2023
Southeast downsloping winds should lead to MVFR to VFR cigs at
CMX and IWD respectively before increasing moisture Friday ahead
of the next frontal system brings back in MVFR cigs and some
patchy fog.
At SAW, IFR to low-end MVFR cigs improve briefly to high-end MVFR
cigs later tonight before lowering back down to near LIFR late
Friday morning with increasing moisture and the possibility of
isolated showers and patchy fog.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 200 PM EST THU DEC 21 2023
Southeast winds of 15 to 25 knots will drop below 20 knots tonight
through Sat night. South winds increase to 15 to 25 knots on Sun
through Tuesday. No gales seen at this time even though a strong
storm system passes well to the south Mon and Tue.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...GS
LONG TERM...07
AVIATION...Voss
MARINE...07
Area Forecast Discussion
National Weather Service Norman OK
547 PM CST Thu Dec 21 2023
...New AVIATION...
.SHORT TERM...
(This evening through Friday)
Issued at 358 PM CST Thu Dec 21 2023
An opened upper trough over the Southern High Plains is still
expected to dig through our Oklahoma/north Texas counties providing
some weak to moderate mid-level forcing for rain through this
evening and overnight eventually exiting southeast Oklahoma by late
tomorrow (Friday) morning. Satellite imagery and surface
observations showing mid-level moisture over the Texas Panhandle
within the trough while both RAP & NAM forecast soundings start
moistening up our mid-levels through the afternoon for the troughs
arrival this evening. Our low-level moisture is already in place
and seeing fairly strong isentropic upglide in the boundary through
the mid-levels as southerly warm air advection will also provide
ascent for light rain precipitation through tonight. Mid to upper
50s dewpoints especially across our southern CWA may be sufficient
to destabilize our un-capped saturated boundary layer for some
additional thunder as models are suggesting surface-based CAPE by
mid-afternoon. The RAP solution may be a bit over aggressive than
other the other models with over 1000 J/kg of SBCAPE with weak deep-
layer shear and tonight`s low-level shifting eastward across
eastern Oklahoma. As a result, any storm that may develop from the
surface would be weak and short-lived, perhaps a few rumbles of
thunder ending this evening.
With rain chances ending well west of I-35 toward sunrise and light
winds as a weak surface low settles across the Southern High Plains,
could see fog develop in that area. Will add patchy fog into the
forecast into the mid-morning hours. Unseasonably warmer
temperatures will continue Friday afternoon with highs well in the
60s as an upper ridge builds in between our next system.
&&
.LONG TERM...
(Friday night through next Wednesday)
Issued at 358 PM CST Thu Dec 21 2023
Our split-flow upper pattern will remain with a deeper amplitude
trough in the sub-tropical jet digging across the U.S. Southwest
which will affect the Southern Plains by Saturday afternoon. However
could see another morning of more widespread patchy fog across our
area in the morning hours prior to this system moving in. Rain
probabilities will be in the 50-60% chances Saturday afternoon and
becoming likely at 80-95% during the evening through overnight hours
as the upper trough is digging through. Cold air coming through
this trough in the mid-levels may steepen lapse rates with
increasing shear for weak mostly elevated storms to develop mainly
across our southern CWA, so will maintain a low probability (20-30%)
for thunder toward the evening and overnight hours. Rainfall
accumulations of 1-2 inches with the higher amounts across
southcentral through southeast Oklahoma.
This upper system will also be pushing a cold front across our area
on Sunday morning although colder air will lag further to our north
and perhaps start coming in Sunday night when the upper troughs axis
starts coming through. Did go slightly cooler for the afternoon
MaxT using the NBM 5% mainly across our north and west and keeping
mild lower 60s across the remainder of our area, although can`t rule
out those could be adjusted cooler getting closer in time. Sub to
near subfreezing temperatures will return Sunday night as the start
for several subfreezing cold mornings into next week and wind chills
on Sunday night into Christmas morning may make it feel much colder.
By Sunday into Monday, a weak trough in the northerly Polar jet will
dig into phase with our exiting trough in the subtropical jet which
could bring much colder Canadian air down through the Central Plains
although not confident how far into our area? Both GFS & ECMWF
ensembles projecting high temperatures early next should remain
cooler than 50 degrees on Monday although they start to differ on
Tuesday. As far as Christmas goes, it will be breezy out of the
northwest producing morning wind chill values in the mid teens
across northwest Oklahoma to the 20s across the remainder of our
area. Temperatures in the afternoon will likely only rise into the
40s and remaining windy through the afternoon.
&&
.AVIATION...
(00Z TAFS)
Issued at 547 PM CST Thu Dec 21 2023
The computer models have not done a very good job with the erosion
of the low-level clouds observed at KLAW and KCSM this afternoon,
and this clearing may try to move a little farther east early this
evening. But MVFR ceilings have already redeveloped at KCDS with
the next surge of low-clouds moving in from the south. So although
MVFR (and even IFR ceilings in south central and southeastern
Oklahoma) are expected, there could be a relatively brief time
period of VFR at some western or central Oklahoma sites this
evening. It is expected the most of the area will be have MVFR if
not IFR ceilings overnight and into Friday morning, beginning to
lift Friday afternoon.
The primary area of rain is moving east and will generally affect
the southeastern, central and north central Oklahoma TAF sites
this evening. But there still appears to be enough signal for some
low-level forcing of light rain across the west this evening that
TEMPO groups are still warranted. We will also have to watch for
the potential of fog overnight, especially in the west.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 55 64 48 63 / 80 0 0 40
Hobart OK 50 64 45 62 / 30 0 0 60
Wichita Falls TX 53 66 50 68 / 40 0 0 60
Gage OK 38 64 40 61 / 10 0 0 50
Ponca City OK 53 62 46 64 / 80 10 0 20
Durant OK 52 67 54 67 / 70 20 20 60
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
SHORT TERM...68
LONG TERM....68
AVIATION...26
Area Forecast Discussion
National Weather Service Reno NV
122 PM PST Thu Dec 21 2023
.SYNOPSIS...
Slight chance of showers expected south of US-50 through Friday.
A cold front will renew slight chances of light showers Saturday
morning. Good holiday travel conditions are expected with the
absence of significant weather. Christmas Day will be dry and
chilly, followed by a potential for unsettled weather for the final
days of 2023.
&&
.DISCUSSION...
A foggy morning for some valleys, a hazy one for others. It was a
foggy start to the day in the Carson and Martis Valley today, though
latest observations and local webcams reveal that the fog has
lifted and left behind most cloudy skies. Another bout of valley
fog is in store tonight into Friday morning. A quick look out the
office window earlier this morning offered quite the hazy scene in
the Truckee Meadows, though better mixing has diluted the urban
haze a bit since.
A compact upper cyclone, offshore of the southern California
coast, will provide just enough large-scale ascent to yield a
15-30% chance of showers in Mono, Mineral, and Churchill counties
today. Accumulation from these showers will be minimal, if any at
all, with some areas south of US-50 receiving a few hundredths of
an inch. Spotty showers will likely linger into early Friday
before tapering off. However, 18Z Hi-Res guidance does hint at
another pulse of showers from Mono County into Mineral County
Friday afternoon.
A quick-moving upper trough will traverse through the PacNW on
Friday, dislodging a cold front that will advance through the Sierra
and western Nevada Friday night and Saturday morning. While this
front will likely be mostly dry, there may be sufficient moisture
ahead of the boundary to squeeze out some precipitation. Blended
guidance indicates a 15-25% chance of showers along the front
Saturday morning. P-type with these showers is expected to be
mainly snow except for valley floors where the chance of snow is
less than 5% per latest blended guidance. Total QPF will be very
light with this frontal passage with localized areas of a couple
hundredths expected. As such, holiday travel should be in good
shape during the days leading up to Christmas as there are no
significant weather impacts anticipated. Otherwise, brisk north
winds in the post-frontal environment will make for a chilly
weekend as highs only reach the 30s and 40s.
Christmas Day will feature a slight warm-up as temperatures reach
the 40s for Sierra communities and upper-40s to low-50s for western
Nevada valleys. For those of you wishing for a White Christmas, I
hate to be the bearer of bad news but odds of precipitation remain
below 15% throughout the day.
Ensembles continue to advertise a wetter pattern for the final week
of 2023 after Christmas Day as troughing is favored in the eastern
Pacific. There remains much spread in the possible outcomes, and
thus confidence is rather low on the details. What we do know is
that chances of showers and gusty winds increase in earnest on
Wednesday with a good chance of showers each day thereafter,
especially in the Sierra. There`s still much to sort out, but the
weather is looking to be more unsettled as we prepare to ring in
2024.
-Salas
&&
.AVIATION...
* Main forecast impact is continued potential for fog, locally
dense, again tonight into Friday morning. Skies aloft are expected
to clear tonight. With continued inversions, good humidity
recovery, and colder temps this all sets the stage for high
potential for fog and low stratus in many valleys tonight and
Friday morning. 90%+ chance of IFR fog at TRK, 70% at CXP/MEV/SVE,
50% at TVL/MMH, and 20% at RNO/RTS/NFL.
* The upper low spinning off SoCal coast could still send a few rain
or snow showers and clouds up into the E Sierra near MMH/BIH
through this evening. Impacts expected to be minimal. Latest HRRR
showing very isolated showers possible in these areas Friday
afternoon.
* Inland cold front rolls through Friday night, which looks to be
mainly dry with gusty N/NW winds to 20 knots. Can`t rule out a few
MVFR -SHSN, with 10-20% odds of seeing a dusting at any given
location both mountains and valleys.
-Chris
&&
.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&
$$