Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/17/23

Area Forecast Discussion

National Weather Service Denver/Boulder CO

 835 PM MST Thu Nov 16 2023

.KEY MESSAGES...

- Mild and dry through most of Saturday

- Weather system for late Sunday into Monday with travel impacts
  expected for the high country, and rain/snow showers for lower
  elevations

- Strong winds and colder temperatures are still forecast for the
  eastern plains Sunday night into Monday. Blowing dust possible.

- Colder temperatures arriving toward Thanksgiving but most
  solutions still dry for Colorado for pre-holiday travel

&&

.UPDATE...
Issued at 835 PM MST Thu Nov 16 2023

Temperature trends are on track for tonight and no changes were
made to those. Area webcams show just some lingering and very
light snow across the high passes. Nudged PoPs down 10-15 percent
in the mountains over time, ending them earlier around sunrise.
Roads across the highest passes could be slick in spots but
additional accumulation will be very light through 5 AM.

The only thing added to the forecast is based on consistent HRRR
and other CAMs generating fog/low stratus across SW Weld County.
GOES-16 nighttime microphysics shows low-level water-based clouds
have indeed formed in this area. Webcams under the clouds so far
have been inconclusive on whether it`s fog or not. In any case,
this area of stratus/fog should expand in pretty much all
directions along the South Platte River valley and westward into
eastern Boulder/Larimer Counties, and eventually the north side of
Metro Denver in Adams/Broomfield/S. Weld Counties. We don`t
expect it to be more than patchy and don`t expect it to be
terribly thick either. It should dissipate between 8 and 9 AM.

&&

.SHORT TERM...(This evening through Friday)
Issued at 120 PM MST Thu Nov 16 2023

Our quick-hitting system is pushing east into the central plains
with rapidly clearing skies for most this afternoon. Northwest flow
is still squeezing a few last snow showers over the west-facing
mountain slopes, and these with linger through the afternoon,
largely dissipating this evening. Additional accumulations above
10,000 ft will be limited, generally no more than 1-2" for the most
favored slopes.

Meanwhile, breezy conditions have materialized across the lower
elevations as expected, with peak gusts mostly in the 30-40 mph
for the urban corridor and far northeast plains. Strongest winds
will occur over the next couple of hours before weakening through
the remainder of the afternoon and evening. Elevated fire weather
conditions will persist in the northeast for a few hours given the
combination of breezy and relatively dry conditions.

Expect a cooler night with much lighter winds and lows slightly
below freezing for the rural plains, and near or slightly above
freezing across the I-25 corridor. A ridging pattern will return for
Friday, leaving us with abundant sun, light winds, and temperatures
5-10 degrees above normal.

.LONG TERM...(Friday night through Thursday)
Issued at 230 PM MST Thu Nov 16 2023

The upper level ridge over the Central Rockies at the start of
this period will shift eastward into the High Plains on Saturday.
This will bring one more dry and mild day to the forecast area.
High temperatures will once again be well above normal with high
confidence of lower to mid 60s for the I-25 Corridor and plains.

While dry weather will persist through Saturday, there`s just a
slight (10-20% chance) that showers reach the high country late in
the day as the next weather disturbance ejects out of the Desert
Southwest. More likely (60-70% chance) these hold off until the
night-time hours Saturday evening and overnight. Some of those
will linger into Sunday morning before the next and potentially
stronger weather disturbance arrives late Sunday into Sunday
night. On the plains, the odds of any precipitation are very slim
and less than 10% Saturday night or Sunday morning due to the
downslope.

For Sunday night and Monday, the models are fine-tuning their
forecasts with regard to the track of the rather potent upper
level disturbance moving southeast across the Great Basin and into
the Southern Rockies. The trends have been further south over the
last 24 hours, and not surprising given the strength of the jet
(150+ knots) coming off the Pacific. However, there is also a
notable subtropical jet which could essentially block the
progression, so there`s still some uncertainty as to how far
south this disturbance ends up. Nonetheless, at this time the
strongest QG forcing is definitely farther southwest of our
forecast area. As a result, there is a fair amount of uncertainty
in the resultant QPF/snow forecasts. Overall, there`s reasonable
agreement in the ensembles that several inches of snow would still
accumulate in the mountains given colder temperatures and
improving orographics, resulting in travel impacts from snow
covered roads and reduced visibility in snow/blowing snow.
Meanwhile, the plains could still see banded or lighter rain/snow
showers start late Sunday night into Monday. We still think the
Palmer Divide would be most favored for snow and potential travel
impacts due to a stronger northerly flow pattern, while locations
farther north like Boulder & Fort Collins would be more likely to
see lighter precipitation amounts if any at all. Ensemble PoPs and
QPF forecasts just don`t do this justice as they`ll miss the
nuances of forecasting in complex terrain.

Another potential impact from the Sunday night and Monday storm
system passing to our south will be the increasing winds. Low
and mid level pressure gradients strengthen as the low pressure
system deepens in the Central and Southern High Plains. Pressure
patterns and gradients will be favorable for strong, gusty winds
and ensemble forecasts support this windy forecast especially for
the plains east of I-25. For instance, ECMWF ensemble averages
show wind gusts greater than 40 mph, but a 20% chance of gusts
greater than 50 mph for Akron and Limon, and a few outliers
showing even higher gusts greater than 60 mph. Those stronger
solutions would support some blowing dust threat given the dry
soil conditions this fall. We`ll keep an eye on this potential,
although if the models do trend more southerly then the max wind
gusts would likely be a little less. Something to watch the next
couple days.

Temperatures will also be turning colder for Monday, with good
agreement of high temperatures a couple degrees below normal, but
the wind and expected clouds will make it feel even colder.

By Tuesday and Wednesday, there should be some warming to offer
up as ridging is generally expected. However, the deep and
elongating eastern trough extending from the upper Great Lakes
could offer up a stronger backdoor cold front. That`s why there`s
a huge spread in ensemble guidance for Wednesday, with even the
25-75th percentiles showing highs for Denver ranging anywhere from
the upper 30s to lower 60s, and the full range of potential
outcomes anywhere from 23-67! Thus, we`ll stick close to the
averages at this time but there`s a lot of uncertainty.

There appears to be more certainty for a more significant colder
air to infiltrate the plains later next week toward Thanksgiving
and Friday. Pre-holiday travel originating in Denver and the
immediate region should be good with dry conditions Tuesday and
Wednesday. Some snow could move about as far south as Wyoming
toward Thanksgiving, but all depends on how fast the next trough
elongates. The return trips into/out of northeast Colorado could
see snow impacts toward Friday and Saturday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 504 PM MST Thu Nov 16 2023

VFR through Friday. High resolution models develop fog across Weld
County after midnight tonight. The same models keep south drainage
winds going all night at APA and DEN, thus it is very hard to get
fog into DEN with a south wind. We have kept any mention of fog
out of the TAF for now given this. For now it looks like fog will develop,
but probably not as widespread as models indicate (they are too
moist in the boundary layer right now across NE Colorado) and the
wind directions are not favorable to bring fog into the terminals
until maybe 5-8 AM. APA should be safe from fog no matter what,
though BJC also has a fog signal in the CAMS through 8 AM. If fog
approaches the airfields, it should dissipate between 8-9 AM more
or less. If CAMS continue to insist the drainage flow weakens by
mid-morning, we will likely need to add a tempo group for fog a
few hours around sunrise (5-8AM or so). Winds will be 6-11 kts all
night at the terminals after 7 PM.

On Friday almost no clouds are expected at any level, and winds
should come around to ESE at 7-10 kts from midday into the
evening hours. Drainage winds will return after 8 PM (SSW at DEN
and APA 7-11 kts, WSW at BJC 6-9 kts).

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE...Schlatter
SHORT TERM...Rodriguez
LONG TERM...Barjenbruch
AVIATION...Schlatter



Area Forecast Discussion

National Weather Service Goodland KS

 148 PM MST Thu Nov 16 2023

.SHORT TERM...(This evening through Saturday)
Issued at 135 PM MST Thu Nov 16 2023

Overview: A split-flow synoptic regime over the western CONUS
will begin to transition to an omega-block this weekend.. as
shortwave energy progressing south of the Aleutian Islands (today)
digs SSE ashore the PAC NW (Sat).. ejecting the stalled low
offshore the Pacific Coast eastward/inland across the
Intermountain West.

Through Tonight: MSLP-H85 height rises in the lee of the northern
Rockies.. associated with synoptic subsidence in the wake of
potent shortwave energy progressing eastward across the Northern
Plains.. will drive a cooler airmass /inverted surface ridge/
southward into the Central Plains this aft/eve.. the leading edge
of which will manifest as an effective cold frontal passage.
Guidance suggests that FROPA will occur around sunset (23-02Z time
frame).. earliest near the NE/KS border and latest south of I-70.
For diurnal reference, sunset is at ~2330 UTC. Forecast soundings
indicate low-level northerly flow on the order of ~25-35 knots at
the onset of low-level cold advection, suggesting a brief period
of sustained winds ~20-30 mph and gusts up to 40 mph, though --
given poor diurnal timing and the relative weak nature of cold
advection (in this case) -- vertical mixing may be insufficient to
fully realize/transport said momentum to the surface. Simulated
reflectivity forecasts via recent and current runs of the HRRR
continue to suggest a potential for very light precipitation
/rain/ invof the CO-NE-KS border this evening -- presumably in
association with cyclonic shear vorticity on the northern
periphery of a ~140 knot WSW upper level jet (extending ENE from
southern CA into southeast CO) and fleeting 850 mb frontogenesis
at the leading edge of the cooler airmass /front/ progressing into
the region from the north -- though, strengthening synoptic
subsidence (in the wake of potent shortwave energy progressing
eastward across the Northern Plains) and weak low-level cold
advection may largely negate/offset said forcing. With this in
mind, measurable precipitation seems unlikely in the GLD CWA.

Fri-Fri night: The mid-latitude westerlies, diverging around the
stalled low (offshore the Pacific Coast) and splitting into two
distinct branches (a northern and southern stream) -- hence,
split-flow -- will converge over the central CONUS in this period.
Expect clear skies.. assoc/w confluent flow aloft. With a newly
deposited (cooler) airmass in place over the region, expect cooler
temperatures (albeit still above-normal) with highs generally in
the lower 60s.

Saturday: An upper level ridge amplifying over the Rockies on
Friday will deamplify and shift eastward across the central CONUS
on Saturday.. in advance of the Pacific Coast low ejecting
eastward/inland across the Intermountain West and 4-Corners.
Expect clear skies and a modest warming trend, with highs in the
mid to upper 60s.

.LONG TERM...(Saturday night through Thursday)
Issued at 111 PM MST Thu Nov 16 2023

Precipitation starting Sunday, followed by a drop in temperatures
Sunday night with very strong winds on Monday.

The big driving force for the majority of the long-term will be
an upper-level trough starting out the period over the British
Columbia coast. Over the first 24 hours of the period, this trough
will quickly amplify and impact the High Plains. Starting about
0Z Sunday, an 850 mb lee low will form in east central Colorado
and begin moving east with the center of low pressure staying on
the southern fringes of the CWA. This low will kick up the LLJ
from the southwest and help funnel moisture into the Great Plains,
specifically the eastern half of the CWA and central Kansas. The
850 mb low will move on east as a 500 mb low begins to form and
provide substantial vorticity to cause precipitation. This first
round of precipitation will last until the evening or overnight
hours on Sunday, and is expected to remain rain. Current PoPs top
out in the 50-60% range in Norton and Graham counties with 20% or
less to the west of highway 27. Due to the strength of the cold
front and conditional instability, there is a slight chance (~20%)
for a few rumbles of thunder to be heard Sunday afternoon in the
far eastern reaches of the CWA. High temperatures Sunday are
expected to warm into the 50s.

Overnight Sunday will be fueled by the 500 mb low stalling out,
potentially retrograding back west, for a few hours and wrapping
around moisture into the lower-levels of the CWA. Sunday night,
the 850 mb low will continue moving east, away from the CWA. A
strong pressure rise is expected behind the low and will increase
the 850 mb winds to around 40 kts from the north some time around
6Z-18Z Monday. This is a major decrease from the 60 kts we were
seeing yesterday, meaning the winds on Monday may not be as
intense as previously thought. The wrap around moisture in the
Tri-State area combined with the stalled 500 mb low providing
enough forcing for a second, more widespread, wave of
precipitation to occur. This round of precipitation looks to last
for about 24 hours starting at 0Z Monday. The best chance for
precipitation will be around 12-18Z Monday with PoPs across the
entire Tri-State area ranging from 40- 60%. There is still a
slowly growing area that could see a rain/snow mix in eastern
Colorado. The limiting factor will be how much cold continental
air will advect into the area. If more advection occurs, the
melting layer will shrink and allow for more snow to reach the
surface. On the other hand, if the low does not advect much of the
continental air in, the melting layer will grow and little to no
snow will make it to the surface. As the guidance currently
stands, a small to moderate amount of this air seems to be making
it into the western CWA. This lends to the forecast of rain/snow
mixed showers with little snow accumulation. Localized areas of
more intense snowfall are possible and could reduce visibility,
especially when combined with the strong northerly winds that are
expected Monday.

Winds have slowed slightly from this morning`s forecast, but have
not changed much from yesterday afternoon`s forecast. This is due
to the decreased confidence of strong 850 mb winds. Starting
around 6Z Monday, as the 850 mb northerly LLJ is speeding up,
winds at the surface are expected to increase, too. By 12Z,
sustained winds at 20- 25 kts with gusts around 25-35 are
expected. Current guidance is showing the most intense winds
starting around 15Z with sustained winds of 20-30 kts and gusts up
around 40 kts. The strongest winds will be in eastern Colorado
and extreme western Kansas. The winds will finally begin slowing
when a weak 850 mb ridge begins to push the LLJ on east, likely
around 0-6Z Tuesday. Prepare for a very windy day Monday.

The strong northerly winds are expected to advect in cold air,
which will cause high temperatures on Monday to be in the 40s. The
amount of cold, continental air that will make it into the CWA is
in question considering model guidance is showing a fairly long
corridor of "warm" air into the Northern Plains. This warm air
will act as a buffer ahead of the cold air that is located farther
north. The mid and low-level low pressure systems systems are
expected to eventually pull in the cold air from Canada, the
question is how long will it take for the warm air buffer to be
depleted. This feature has lowered confidence in the efficiency of
the CAA. Monday night`s lows are now expected stay in the 20s,
due to the weaker CAA. Winds Tuesday morning will still be from
the north-northeast at 15-20 kts, gusting to 30 kts, and will
cause wind chills across the region to be in the single digits to
lower double digits.

During the day Tuesday, strong, northerly upper-level flow will
move over the CWA as a weak ridge begins to move over the
southwestern CONUS. This will work to push out any remaining
clouds, allowing Tuesday to warm up to around 50.

From Tuesday night onwards, the forecast has very little
confidence. Over the past 24 hours, guidance is showing the mid
and low-level low pressure system, centered near the Great Lakes
region, to continue advecting cold air into the region. This is a
complete flip from 24 hours ago when a ridge was expected to nose
in and allow us to warm up. To highlight this variation, the
current GEFS 2 meter temperatures run has a 48 degree spread at
18Z on the 22nd. It seems unlikely that more precipitation will
occur after Tuesday evening, but once again, confidence is low.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 145 PM MST Thu Nov 16 2023

VFR conditions will rule through the TAF period at both
terminals, with ceilings largely confined to the upper levels
(18,000+ feet AGL). NNW winds at 10-15 knots will veer to the N
and gust up to ~20 knots late this afternoon. Winds will further
veer to the NNE and increase to 15-25 knots around sunset this
evening (23-00Z).. in association with pressure rises attendant
an effective cold frontal passage. Breezy NNE to NE winds are apt
to be short-lived (~2-3 hours) in nature, decreasing to 10-15
knots later in the evening (~04-05Z) and becoming light/variable
overnight.. as surface high pressure over the Dakotas extends
southward over the Central Plains. Clear skies and light/variable
winds will prevail throughout the day on Friday.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

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



Area Forecast Discussion...Updated

National Weather Service Lincoln IL

 750 PM CST Thu Nov 16 2023

.SYNOPSIS...
Issued at 750 PM CST Thu Nov 16 2023

Southwesterly winds will continue to be breezy ahead of a cold
front, which will reach the Illinois River late tonight. The
front will bring light rain to the area late tonight through
Friday, and the return to seasonable temperatures for Friday into
the weekend. Looking ahead, a low pressure system is on track to
bring rain and breezy winds to the area early next week.

&&

.UPDATE...
Issued at 750 PM CST Thu Nov 16 2023

A mild evening continues across the forecast area, with 7 pm
temperatures still in the upper 50s or lower 60s in many areas.
Radar mosaics are showing some echoes moving into western
Illinois, though our evening sounding shows only a small area
around 800 mb is saturated, and no upstream obs are currently
reporting rain. Forecast soundings near Galesburg off the HRRR
show some decent moistening of the lower layers taking place over
the next few hours, though still remaining dry above 750 mb. Thus,
a gradual increase in PoP`s there still appears warranted, though
the bulk of it would be after midnight. Further southeast, while
there are still a few models suggesting some light showers this
evening, more of an uptick is likely after midnight.

With the front itself, 7 pm surface observations show it just
northwest of Des Moines. Latest high-res models continue to
suggest its arrival near the Illinois River toward 3 am, the I-55
corridor around 6 am, and I-70 toward 10-11 am. Temperatures
remain mild much of the night, but will quickly drop off with the
front, and a general decrease will continue into mid morning
before leveling off.

Recent updates were sent to adjust timing of rain chances, as well
as tweaks to the hourly temperatures into midday.

Geelhart

&&

.SHORT TERM...  (Through Late Friday Afternoon)
Issued at 311 PM CST Thu Nov 16 2023

A cold front is still expected to move into the area tonight and
bring light rain late tonight through tomorrow. QPF amounts are
still expected to be very light with totals of around one tenth of
an inch likely. The rain will have to overcome a very dry airmass
currently over the area. So, initial precip will go to moistening
the lower layers before precip actually reaches the ground. Pops
will be lower to the west and higher across eastern and
southeastern IL late tonight and tomorrow, but again, QPF amounts
will still be light. Winds will remain breezy ahead of the front
this evening but begin to decrease as the front arrives later
tonight. Overnight lows will still be warm ahead of the front
which will be in the east and southeast where temps will be in the
50s. Behind the front, cooler air will advect into the area and
lows will drop into the 40s. Behind the front, winds will become
west to northwest but not be as breezy as they are this afternoon.

Auten

&&

.LONG TERM...  (Friday Night through Next Thursday)
Issued at 311 PM CST Thu Nov 16 2023

Though the temperatures this weekend will be cooler than they have
been the last several days, highs in the 50s for Sat and Sun will
actually be around normal for middle of Nov. Dry weather is also
expected over the weekend as a brief high pressure ridge slides
across the area. As this high pressure moves into eastern US a
stronger, better defined weather system will deepens and move out
of the plains, into the midwest for the beginning of the new week.
All the models are similar with intensity and location of the
precip associated with this system, but there are still some
differences with the timing of the start of the precip. GFS seems
to be the quickest with onset but all look similar with ending
time. Consensus is precip will be ongoing Mon and then continue
into Tue. However, adding the quicker GFS, will have some minor
precip in the southwest part of the CWA Sunday night after
midnight. Mon afternoon through Mon night, precip will definitely
be occurring and all models have been consistent with this general
forecast. Precip will continue into Tue morning, but begin to
diminish Tue afternoon. The remainder of the extended period, Tue
night through Thursday is expected to be dry, but much colder
temps are expected for the last half of the week; which will be
much below normal. Daytime highs only be in the 30s with lows in
the 20s.

Auten

&&

.AVIATION...  (For the 00z TAFs through 00z Friday Evening)
Issued at 520 PM CST Thu Nov 16 2023

Main aviation concerns will accompany a cold front, which will
sweep across central Illinois late tonight and Friday morning. VFR
conditions expected through about 06Z, then a gradual lowering of
ceilings will take place as the front begins to move in. Ceilings
likely to decrease to below 2,000 feet by 09-10Z. HREF and NBM
guidance suggests a period of IFR conditions near KDEC/KCMI for an
hour or two Friday morning (about a 40-50% chance). A quick
improvement in ceilings will spread in from the west, and all
sites should be VFR again by 18Z.

Ahead of the front, some gustiness will linger overnight, mainly
in eastern Illinois, as winds trend more southwest. Frontal
passage is expected toward 09-10Z at KPIA and ranging up to 13-14Z
at KCMI, when winds switch to the northwest, and then north after
a few hours. While wind gusts behind the front are not expected to
be substantial, sustained speeds over 10 knots are likely the
remainder of the forecast period.

Geelhart

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$



Area Forecast Discussion

National Weather Service North Platte NE

 525 PM CST Thu Nov 16 2023

.KEY MESSAGES...
- Slight chance (35% or less) for light rain showers/sprinkles
  continues through this evening for portions of western and
  southwestern Nebraska.

- Quiet and dry Friday and Saturday with above normal temperatures
  in the 50s and 60s.

- Precipitation chances increase Sunday into Monday, becoming
  breezy and cooler on Monday.

- Temperatures trend back towards the below-normal range Wednesday
  into the end of the week, just in time for the Thanksgiving
  holiday.

&&

.SYNOPSIS...
Issued at 223 PM CST Thu Nov 16 2023

Recent GOES-16 WV and RAP 500-mb analysis showed a slow moving
trough of low pressure centered off the coast of California.
Further northeast of this feature, a deep upper-level low
pressure system was centered over the Hudson Bay with a trough
extending south into the northern Plains. In between the two
upper-level troughs, a transitory ridge was apparent across the
southern Plains. Another upper-level trough was noted over
Florida, extending south across the Gulf of Mexico and Cuba. At
the surface, low pressure was noted across the Upper Midwest
with an associated cold front draped across the northern
Sandhills. With 3 to 5 mb/3 hour pressure rises and strong cold
air advection (CAA) behind the front, northwesterly winds have
become gusty with recent area observations of 30 to 35 miles per
hour. Weak frontogenetical forcing along and behind the front
has taped in to the meager precipitable water values across the
area resulting in sprinkles to light rain developing across the
Panhandle into the Sandhills. The precipitation was struggling
to reach the ground given the amount of dry air that was present
this morning, though since overcome it. The expectation is that
these showers will continue into the evening hours with minimal
accumulations of a few hundreths at most anticipated. The
frontal passage has brought a range of temperatures across the
area with 2 PM CT temperatures having ranged from 54 degrees at
Gordon to 71 at Broken Bow.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 223 PM CST Thu Nov 16 2023

Tonight...Strong surface high pressure will continue to build in
from the northwest through the overnight. The gusty northwest winds
decouple quickly around sunset with much colder overnight
temperatures thanks to the strong CAA overspreading the area. Though
still remaining seasonable for the middle of November, lows will
fall into the 20s under gradually clearing skies in response upper-
level moisture plumes moving east across the northern Plains.

Friday and Saturday...The aforementioned upper-level ridge will
build further into the Rockies and northern Plains with mostly sunny
skies. Highs will continue to remain 15 to 20 degrees above normal
in the 50s and 60s.

&&

.LONG TERM /FRIDAY THROUGH THURSDAY/...
Issued at 223 PM CST Thu Nov 16 2023

A pattern shift is expected Sunday into Monday as the upper-level
troughs from the southern and northern stream converge over the
region, shunting the upper-level ridge eastward. A developing system
in the southern stream will move from the Four Corners Saturday
night into the Central and Southern Plains Sunday into Monday. At
the same time, an upper trough in the northern stream will move
southeast from the Pacific Northwest into the central Rockies,
centering over northern Kansas into eastern Nebraska Sunday
afternoon. A lee-side trough develop across southeastern
Colorado on Sunday, deepening as it tracks into the southern
Plains through Monday. This will result in increased synoptic
forcing bringing increased precipitation chances back into the
forecast for Sunday and Monday. Temperatures support rain being
the predominate precipitation type for a majority of the area.
However, overnight lows fall around or below freezing Monday
morning for the Pine Ridge area into the western Sandhills
which would support a transition to rain/snow mix and/or a brief
snow shower. Precipitation chances linger through Monday
afternoon. Increased potential of locations seeing over 0.5" is
favored across southeastern into portions of central Nebraska
with less amounts across southwestern and northwestern Nebraska. While
this system will bring a good opportunity for rainfall,
confidence is lowered given the variability amongst model
solutions. However, expect the spread amongst model solutions
to narrow with subsequent forecasts which will help iron out the
exact details. Regardless, Sunday into Monday evening appears
the best chance for wetting moisture across western and north
central Nebraska.

What may be more impactful will be the potential for strong
winds Monday into Tuesday. A strong surface pressure gradient
(SPG) across the central Plains and a northerly low-level jet
(LLJ) will result in a period of strong winds across much of the
local area. At this time, the strongest gusts up to 30 to near
40 miles per hour are anticipated on the northwestern periphery
of the surface low. Though this remains to be 4 days out,
forecaster confidence is increasing due to the EFI (Extreme
Forecast Index) highlighting this potential such that the SoT
(Shift of Tails) is greater than 0 across portions of the
forecast area.

Outside of the potential for precipitation and strong winds,
high temperatures will fall back to seasonal values in the 40s
Monday and Tuesday before trending back into the well-below
normal range Wednesday into the Thanksgiving holiday weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 525 PM CST Thu Nov 16 2023

VFR conditions should continue, although a thick mid level
cloud deck will remain in place through the late evening hours
across western and north central Nebraska. A few light rain
showers will also move through the area around sunset. Gusty
north winds will taper to light and variable tonight, then
strengthen slightly toward midday out of the west/northwest.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Viken
SHORT TERM...Viken
LONG TERM...Viken
AVIATION...Snively



Area Forecast Discussion

National Weather Service Los Angeles/Oxnard CA

 327 PM PST Thu Nov 16 2023

.SYNOPSIS...16/222 PM.

Mild temperatures with mostly rain-free conditions will continue
into Friday afternoon. Widespread rain will follow Friday Night
through Saturday, with a potential for thunderstorms and brief
heavy downpours. Showers will follow then quickly dissapate
Saturday Night into Sunday. Moderate to strong north winds are on
tap for Sunday, with weak to moderate northeast winds Monday and
Tuesday. Warming and drying conditions will result Sunday through
Wednesday.

&&

.SHORT TERM (TDY-SUN)...16/216 PM.

Our low pressure system is currently centered 600 miles west of
Santa Maria. This is further off the coast than yesterday, which
has pulled most of the clouds and showers off the coast. This
should remain the story into Friday afternoon, with a few showers
possible, mainly over San Luis Obispo and Santa Barbara Counties,
but most of the area will stay dry. With the added sunshine and
locally breezy southeast flow, the daytime hours will be rather
pleasant for most, with highs around 70 common.

The low pressure system seems locked in to move towards and
through California Friday Night through Saturday. This will usher
in our next band of organized widespread rainfall to the region.
Steady rain will start over the Central Coast by Friday afternoon
or evening, then move south Friday Night through Saturday morning.
Showers will likely follow Saturday afternoon, which will taper
off quickly Saturday Night. Uncertainty in the timing is plus or
minus 6 hours. There remains a healthy spread in the different
ensemble models, with the EPS consistently showing higher amounts
over the GEFS and CMC. Will start to lean the official forecast
into the EPS solution but not go all in for the following reasons.
The rainfall totals from yesterday ended up being closer to the
EPS than the others. Some of the high resolution models are
showing rainfall rates over 0.50 inches per hour, with the latest
few runs of the HRRR showing some rates of 1.00 to 1.50 inches per
hour. The air mass looks unstable with isolated to scattered
thunderstorms expected nearly anywhere. If the HRRR or EPS
verifies, there would be a real threat for significant roadway and
small creek flooding. With all that in mind, trended the expected
rainfall totals up, especially for San Luis Obispo and Santa
Barbara Counties where the added messaging of a 20 percent chance
of rainfall exceeding expected totals by 1 or 2 inches will also
be applied.

Southeast winds will also be on the rise. While they do not look
as strong as yesterday, they will still be impactful especially in
the mountains and possibly southwest Santa Barbara County where
gusts of 30 to 45 mph are expected. Snow levels remain high, and
above 7,500 feet for most if not all of the precipitation. Snow
impacts will be minimal as a result.

The low pressure system will move into Nevada by Sunday evening,
which will help pull another trough from the Pacific Northwest
deep into Utah by Sunday. A 100-120 knot northwesterly jet will
push over California, with quickly tightening north to south
pressure gradients. This will bring a moderate to potentially
strong north wind event by Sunday afternoon and evening. Gusts of
40 to 60 mph are likely for the mountains including the I-5
Corridor, Santa Monica Mountains, and Montecito Hills. Gusts of 20
to 40 mph will be common elsewhere, including the Central Coast,
Casitas, Santa Clarita Valley, San Fernando Valley, and possibly
the LA Coastal areas. While these winds will dry out and warm up
the coasts and valleys, lingering moisture should pile up on the
north slopes and bring a few rain showers up there.

.LONG TERM (MON-THU)...16/223 PM.

There is good consensus among the ensemble projections for a weak
to moderate Santa Ana wind event for Monday and Tuesday. Gusts of
25 to 45 mph are expected, with a range of outcomes plus or minus
10 mph. Along with a building ridge of high pressure, temperatures
will climb to the mid 70s to mid 80s, warmest over the coastal and
valley areas. Fire weather concerns will be limited thanks to the
recent rains. Weak offshore flow and warm conditions will carry
over into Wednesday. Beyond that, all indicators show a quick
shift to onshore flow and cooling conditions as an inside slider
moves into the western United States.

&&

.AVIATION...16/2327Z.

At 2300Z, there was no marine inversion at KLAX, but a deep moist
layer extended up to around 8000 feet.

Overall, low to moderate confidence in coastal/valley TAFs and
high confidence in desert TAFs with 00Z TAF package. Confidence in
development of MVFR CIGs overnight for coastal/valley sites is
only moderate at best.

KLAX...Overall, moderate confidence in 00Z TAF. Through this
evening, high confidence in VFR conditions. Overnight, there is a
60% chance of MVFR CIGs 09Z-18Z. No significant easterly wind
component is expected.

KBUR...Overall, moderate confidence in 00Z TAF. There is a 30%
chance of MVFR CIGs 10Z-18Z.

&&

.MARINE...16/220 PM.

For the outer waters and the inner waters N of Pt Sal, Small
Craft Advisory (SCA) level SE winds and seas have been lingering
across the northern outer waters (north of Pt. Sal), so have
reissued a SCA for these waters. There may be a dip in winds
overnight, but by Friday mid-morning, SCA level winds will expand
across the outer waters and northern inner waters. Winds will
shift to the NW and drop below advisory levels through the morning
hours on Saturday. However, there is a 30-40% chance of winds
increasing to strong SCA levels overnight Saturday, bringing a 20%
chance of Gale Force wind gusts Sunday into Monday. Short-period,
choppy seas will increase to SCA levels on Sunday into Monday.

For the Santa Barbara Channel, SE winds will remain below SCA
levels through Friday morning, then there is a 40-50% chance of
SCA level SE winds Friday afternoon into early Saturday, mainly
across the western portion. Winds should shift W by Saturday
afternoon. There is a 30% chance of winds increasing to SCA levels
overnight Saturday and possibly lasting into Sunday evening.

For the southern inner waters, E-S winds will likely remain below
SCA level through Saturday morning, and then shift W-NW Saturday
afternoon. There is a 30% chance of SCA level SE-S winds Friday
night and early Saturday. There is a 20% chance of NW-N SCA level
winds on Sunday afternoon into late night.

There is a chance of thunderstorms late Friday into Saturday
across most of the coastal waters. Any thunderstorm that forms can
bring locally gusty winds, small hail, and dangerous lightning.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 10 AM to 10 PM PST Friday for
      zones 353-377-378. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from 9 AM Friday to 3 AM PST
      Saturday for zone 645. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PST Saturday for
      zone 670. (See LAXMWWLOX).
     Small Craft Advisory in effect from 3 AM Friday to 3 AM PST
      Saturday for zone 673. (See LAXMWWLOX).

&&

$$

PUBLIC...Kittell
AVIATION...RAT
MARINE...Lund/DB
SYNOPSIS...RK

weather.gov/losangeles

Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox



Area Forecast Discussion

National Weather Service Marquette MI

 658 PM EST Thu Nov 16 2023

.SHORT TERM...(This afternoon and overnight)
Issued at 113 PM EST THU NOV 16 2023

Water vapor imagery and RAP analysis position the UP under the
influence of strong southerly flow ahead of an approaching shortwave
pressing through the Northern Plains. As of 18z, the cold front
associated with this shortwave was located moving into the Arrowhead
from the west. SPC mesoanalysis paints a strong low level jet of 45
to 50kts at 925mb across our forecast area. Temps ahead of the front
have been under a warm air advection regime and mixing has not only
been able to support winds upwards of 30-40kts at some sites, but
daytime highs climbing into the mid-upper 50s with some low 60s
sprinkled in here and there. Some mid to upper 60s have also been
reported so far in the west. Behind the cold front across the
Dakotas and northwest Minnesota, temps have been largely in the 30s
or low 40s today.

As we progress through the remainder of the afternoon and overnight
period, expecting the winds to remain until the front moves through
later this evening. The highest gusts are expected late this
afternoon when mixing is maximized due to dinural heating while the
40-50kt 925mb low level jet remains overhead. While winds so far
have underperformed some, I`m still confident (>75%) that 45 mph
wind gusts will be realized near Lake Superior in a number of
locations.

There`s some small differences in when the frontal passage will take
place, but the rough consensus is that it should be around 5-8pm in
the west, 7-10pm central, and 9pm to midnight in the east. Light
rain ahead of the front should press west to east. Expecting the
upstream colder air to build in immediately behind the front,
supporting a quick drop in temps, some snow mixing in with any lake-
effect showers that develop, and a wind shift to the northwest.
Winds should settle through the night, but immediately behind the
front, wind gusts may gust upwards of 30-40 mph, highest near Lake
Superior. Lake Superior lakeshore areas may continue to see winds in
excess of 25 mph through the night. Overnight lows should dip into
the upper 20s or low 30s.

.LONG TERM...(Friday through Thursday)
Issued at 434 PM EST THU NOV 16 2023

Key Messages:
-Seasonable temperatures trend below-normal by midweek with Saturday
and Monday expected to be the warmest days.
-Light lake effect chances, mainly across the east Friday morning.
-For anyone with travel plans during the week of Thanksgiving,
please continue monitoring forecasts as chances are increasing for a
moderate rain/snow mix Tuesday transitioning to several days of
potentially heavy lake effect snow.

There is good model agreement through the weekend and Monday with
some uncertainty beginning Monday night as we track out a mid level
low and associated sfc low northeast from the Lower Mississippi
Valley into the Great Lakes Basin. Starting Friday morning, a mid
level shortwave trough will be situated over Ontario, rotating into
Quebec. CAA will hinder diurnal warming with 850 mb temps cooling to
around -10C; highs will feel much cooler than today as they drop
back down near normal in the mid 30s to low 40s. With supportive
Lake Superior sfc-850mb Delta-Ts and inversion heights around 4-6
kft, some lingering lake effect showers and flurries are possible
over the east in the morning. Confidence however is low (>30%) as
model soundings show the moist layer below the DGZ and inverted v
structure extending up to around 2-3 kft, sfc ridging juts in from
the west shifting winds in the afternoon, and low level convergence
is lacking. Any showers that are able to develop are not expected to
yield any accumulations. Light winds in the morning will taper down
through the day becoming southwest in the afternoon as cloud cover
diminishes.

Our attention then turns to a low tracking through Northern Ontario
Friday night into Saturday, continuing east into Quebec Saturday
evening before phasing with a low off the Atlantic Coast. Guidance
has been moving toward a dry solution for our CWA, shifting the
track of this low farther north of the CWA. Also model soundings
lack good moisture with such weak forcing to yield much of any
precip. This lack of moisture along with similar conditions to the
previous lake effect showers mean chances for lake effect showers
Saturday night into Sunday are minimal. WAA will help yield the
warmest day of the extended forecast for Saturday with highs in the
40s. Dry weather then is expected to continue through Monday with
plenty of sunshine mixing into the forecast.

Moving into Monday evening, the main story of the extended comes
into play. Strong ridging will start out over the west coast with
weaker ridging over the northeast coast. Two troughs, one
subtropical and one polar, amplify Sunday night into Monday before
undergoing some complex phasing Tuesday into Wednesday over the
Great Lakes Basin. This will ultimately result in a deep mid level
low over the northern end of the Basin and Ontario mid next week.
The subtropical trough will develop a sfc low over the southern
plains Sunday night that tracks east into the Lower Mississippi
Valley on Monday before tracking northeast into the Great Lakes
Basin. Ensemble guidance is beginning to close in on the track, but
both ECMWF and GFS ensembles have a second group of members that
continue farther east toward the east coast instead of northeast
into the Basin. The polar tough`s sfc low stays over the northern
end of the Prairie provinces on Monday, heading eastward over Hudson
Bay Tuesday. As these two troughs phase on Tuesday, amplified
troughing will swing southeast through NE Minnesota and then the
U.P. A associated cold front will push east through the region on
Tuesday. Between the PVA and the frontal boundary, there will be
ample forcing for precip through the mid week. 850mb temps behind
the cold front drop below -10C, staying in the negative teens
through next week yielding a supportive Delta-T for LES over the NW
becoming NNW wind snow belts. Overall, we can expect a rain/snow mix
starting Monday night into Tuesday which transitions to all snow on
Tuesday behind the cold front with potential for moderate to heavy
LES trailing behind the system. If you have any holiday travel
plans, continue to monitor this forecast as guidance begins to hone
in on a solution. You may need to consider a contingency plan.
&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 658 PM EST THU NOV 16 2023

Sharp cold front has entered the western U.P. as of 00z. It will be
accompanied by -shra lasting about an hr or so as it quickly sweeps
e thru the evening. At IWD, -shra are e of the terminal. Expect nw
winds gusting 35-40kt for the next hr or so, then winds will
diminish thru the night. There is a band of lower clouds, MVFR cigs,
in ne MN, and those MVFR cigs will reach IWD this evening. While
this fcst has MVFR cigs scattering out to VFR overnight, they may
linger into early Fri morning. Otherwise, VFR will prevail at IWD on
Fri. At CMX, -shra in the vcnty will exit in the next hr. Expect nw
winds gusting up to 45kt for the next couple of hrs and then to
around 40kt for the remainder of the evening. Winds will then
diminish overnight into Fri morning. As with IWD, expect MVFR cigs
to arrive at CMX this evening. The MVFR cigs will probably linger
thru Fri morning before scattering out to VFR. At SAW, LLWS will
continue ahead of the cold front for another couple of hrs. With
fropa, sfc winds will shift w to nw, gusting to around 30kt, and
expect an hr or two of -shra. Postfrontal downslope nw winds at SAW
should keep cigs from falling to MVFR. Winds will diminish overnight
with VFR prevailing thru Fri.
&&

.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 434 PM EST THU NOV 16 2023

Good model agreement on the expected synoptic pattern continues this
forecast package and not many changes were made.

A strong low level jet is over the lake, yielding some gusty
southerly winds going into this evening. These winds lead up to a
cold front expected to quickly cross the lake this evening. Behind
the front, strong cold air advection and rapid pressure rises result
in gusty northwest winds. Strongest wind speeds will occur at
observation platforms above the 10m forecast height where they will
be more exposed to stronger mixing. The pressure gradient is more
than adequate to support gales across the lake with the strongest
winds expected over the east. Internal probabilistic tools suggest
between 45% and 60% chance of high end (>40 kt) southerly gales this
evening into tonight. Chances for storm force gusts (>47 kt) remain
low (>20%), over the far east if any are able to mix down at all the
rest of today as mixing weakens toward sunset. Downsloping winds off
of terrain near the lakeshores will also be possible, particularly
in the shipping lanes near the Keweenaw and points eastward. Winds
aloft quickly diminish behind the front suggesting winds falling
below gales Friday morning.

Models continues to trend farther north/east with a clipper system
tracking southeast across Ontario on Saturday. West-southwest to
west winds ahead of the clipper increase to 25-30 kts across western
and north-central portions of the lake Friday night. Elevated west
winds around 25 kts continue on Saturday before veering northerly
behind the clipper Saturday evening and dropping below 20 kts
Saturday night. Winds are expected to remain below 20 kts through
Monday when Gale potential returns to the forecast with our next
system.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Wind Advisory until 10 PM EST this evening for MIZ001-003.

  Wind Advisory until 9 PM EST /8 PM CST/ this evening for MIZ002-
     009.

  Lakeshore Flood Advisory until 4 AM EST Friday for MIZ013-014.

Lake Superior...
  Gale Warning until 7 AM EST /6 AM CST/ Friday for LSZ162-240>242-
     263.

  Gale Warning until 10 AM EST Friday for LSZ243>251-264>267.

Lake Michigan...
  Gale Warning until 1 AM EST Friday for LMZ221-248-250.

&&

$$

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



Area Forecast Discussion

National Weather Service San Francisco CA

 402 PM PST Thu Nov 16 2023

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1225 PM PST Thu Nov 16 2023

Isolated to scattered rain showers and a slight chance for
thunderstorms will persist through the day. A more steady band of
rain with push across the region by Friday afternoon/evening. Rain
showers will linger into the first part of Saturday before
clearing by Sunday. Temperatures warm to above seasonal averages
Monday and beyond.

&&

.SHORT TERM...
(This evening through Friday)
Issued at 1225 PM PST Thu Nov 16 2023

Isolated to scattered rain showers with a slight chance of
thunderstorms is expected from this afternoon and into the
evening. Instability will increase enough to warrant a mention for
convection by this afternoon. By tonight, mostly dry conditions
are expected.

Friday afternoon/evening is when a better defined band of
precipitation sweeps inland resulting in light to moderate
rainfall. Again, chances for thunderstorm exist on Friday which
will linger into Friday night. As such, locally heavier rainfall
will be possible with any thunderstorm or more convective cells
that develop. As mention in previous discussions, the threat for
flooding remains extremely low.

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 1225 PM PST Thu Nov 16 2023

Post frontal rain showers will continue into Saturday morning
before diminishing throughout the day. Additional rainfall is
expected to range from 1.00"-2.00" in the coastal ranges,
generally 0.50"-1.00" in the City, North Bay and wetter pockets of
the region, and less than 0.50" elsewhere.

By Sunday and beyond, drier conditions are likely to persist.
Monday a subtle warming trend will occur as high pressure builds
aloft. Colder overnight temperatures are also expected next week.

&&

.AVIATION...
(00Z TAFS)
Issued at 342 PM PST Thu Nov 16 2023

VFR conditions are expected through the TAF period for the
majority of terminals, with the chance for ceilings to drop into
MVFR category late Fri afternoon. A few scattered showers are
currently observed on radar, and the chance for a lightning strike
or two will persist through the evening. The TAFs for STS, SJC,
and LVK have VCSH through 02Z, as the storms are too isolated to
show anything more definitive. It is quite possible for showers to
hit these or other stations, and some amendments may be needed
over the next few hours as the storms materialize. Otherwise,
rain returns to the forecast from south to north starting Fri
morning in the Monterey Bay, and reaching the North SF Bay by
early Fri afternoon.

Vicinity of SFO...Currently VFR with several mid-level cloud
layers and light NE wind. The biggest question for the remainder
of the day is whether a shower will hit the terminal. The current
radar loop looks to keep storms to the East of SFO, and OAK
probably has a better chance. The TAFs don`t explicitly mention
showers today as the confidence is just too low. By tomorrow, the
rain should return around 20Z and persist on-and-off for over 6
hours. This persistent rain fall may lower the ceilings to MVFR
after 00Z at both SFO and OAK.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Shower activity has decreased
substantially this afternoon and MRY and SNS should remain dry
through early morning. The rain is expected to return around 15Z,
but there is some uncertainty between different models. The TAFs
leans towards the earlier HRRR guidance. One concern is the wind
speed at SNS Fri. The surface winds should soon decrease to a
gentle breeze and remain that way through the night. Stronger SE
winds will persist in the middle atmosphere, and the rain may help
bring these winds down to the surface Fri morning. As such, the
TAF calls for 12020G30kt to begin at 16Z, which is stronger than
most guidance.

&&

.MARINE...
(Tonight through next Tuesday)
Issued at 342 PM PST Thu Nov 16 2023

On and off chance for thunderstorms continues into Saturday across
the coastal waters. Occasional gale force gusts are possible near
thunderstorms should they develop, but not expecting long
lasting, widespread gale force conditions. However, fresh to
locally strong southerly breezes will develop Friday into
Saturday. Low pressure will dissipate as it moves inland Saturday
and rain chances will diminish by Sunday. In addition,
southwesterly swell will build tomorrow night into Saturday and a
new northwest swell train arrives Sunday.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Friday to 3 AM PST Saturday for
     PZZ540-545-560-570.

     Small Craft Advisory until 3 AM PST Saturday for PZZ565.

     Small Craft Advisory from 3 AM Friday to 3 AM PST Saturday for
     PZZ575.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Flynn
MARINE...McCorkle

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Area Forecast Discussion

National Weather Service Blacksburg VA

 1030 PM EST Thu Nov 16 2023

.SYNOPSIS...
High pressure overhead shifts east through Friday morning. A
front enters the mid-Atlantic Friday night. Scattered showers
will be possible, mainly for the mountains. Cooler weather
arrives for the next several days. After a dry weekend, rain
chances increase again for early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 1030 PM EDT Thursday...

Made some adjustments to hourly temperatures this evening just
to get closer to current cooling trends. No major changes were
made. Smoke will settle into the valleys again tonight so expect
continued visibility reductions and bad air quality over
Amherst/Rockbridge/Bedford Counties.



As of 1205 PM EST Thursday...

Key Message:

1. Increasing clouds late tonight into Friday.Showers possible
in the mountains Friday afternoon.

2. Wildfire smoke impacting the Bedford/Amherst/Botetourt/Rockbridge
areas this afternoon.

High pressure will slowly shift east tonight through Friday
morning. Flow turns more south and will likely see humidity
levels surge upward above 50 percent Friday.

For this afternoon/evening HRRR Smoke models showing the plume
of smoke from the wildfire near the Bedford/Rockbridge/Amherst
intersection will start overspread Rockbridge into portions of
eastern Alleghany and Bath counties, before somewhat dissipating
later tonight. The smoke will cross parts of I-81 and perhaps
I-64, but should stay somewhat elevated this afternoon but could
settle to the ground by dusk.

Clear skies will start cloud up late tonight into Friday morning
thanks to southwest flow aloft advecting moisture in ahead of
the cold front. This front will stay west of us through tomorrow
but enough low level convergence ahead of it allows for a few
showers to reach as far east as the I-81 corridor but best
chances arrive after Friday afternoon.

With increasing moisture, lows tonight will be in the 40s for
most, then warming into the 60s Friday.

Forecast confidence is moderate.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 1220 PM EST Thursday...

Confidence is high for gusty winds on Saturday, then dry weather
will resume for the remainder of the weekend.

A cold front will reach the Appalachian mountains on Friday
night to provide light rain. However, a separate low pressure
system well offshore will promote subsidence across the Piedmont
to cause any moisture to struggle with crossing the Blue Ridge.
Rainfall amounts should vary from near zero in the Piedmont to
around a third of an inch along the higher elevations of
southeast West Virginia.

By Saturday, the wind should turn towards the northwest and
increase. Gusts up to 35 MPH will be possible for the higher peaks
of the Blue Ridge. Any lingering moisture should vanish by midday,
but it is possible for a couple snowflakes to mix with the rain in
western Greenbrier County as cold air advection increases. High
pressure should build across the Mid Atlantic during Saturday night
and persist through Sunday night to provide dry weather.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 1220 PM EST Thursday...

Confidence is moderate for widespread rainfall during Monday night
and Tuesday, then gusty winds should follow for Wednesday.

High pressure will drift eastward on Monday, and clouds will
increase as a potent low pressure system approaches Tennessee.
Moisture with this system should spread into the Mid Atlantic during
Monday night and provide a widespread and beneficial rainfall
throughout Tuesday to help in alleviating the ongoing drought
conditions. Some gusty southeast winds are possible ahead of the
cold front, especially west of the Blue Ridge.

The wind will shift towards the west on Wednesday and become gusty
after the frontal passage. Any lingering rain showers in the
mountains may switch to snow showers as cold air advection
intensifies. Temperatures will plummet by Wednesday night as the
moisture dissipates and high pressure builds eastward. Thanksgiving
Day appears dry and about ten degrees cooler than normal. The wind
may still be breezy but not as strong compared to Wednesday.

&&

.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
As of 705 PM EST Thursday...

Mostly VFR conditions are expected through the period. Clouds
increase and lower ahead of a front Friday morning, but
generally looking at ceilings in the 3-10kft range.

With low level moisture increasing ahead of a cold front, a few sub-
VFR ceilings with showers possible late Friday night in the far
western mountains, close to the end of the valid 24hr TAF
period.

Winds remain out of the south around 10mph.


Extended Aviation Discussion...


Improving conditions everywhere by mid morning Saturday.

VFR into Monday before another system arrives late Monday for
the mountains and Tuesday for the remainder of the area. Higher
chances of rain as well as MVFR/likely lower/ ceilings are
expected in -RA/RA Tuesday. Rain showers may linger in the west
on Wednesday.

&&

.FIRE WEATHER...
As of 715 PM EST Thursday...

Smoke will once again settle into the Shenandoah Valley tonight.
Areas seeing the heaviest concentration of smoke will be
Botetourt/Rockbridge/Bedford/Amherst Counties.

Air quality in these areas will continue to be poor. Some areas
of low visibility will also be possible.

According to the HRRR near-surface smoke, should see another
increase in smoke tomorrow afternoon, favoring Rockbridge County
and the cities of Lexington, Buena Vista and other communities
in the vicinity.

Burn bans or burn restrictions are in effect for many counties.
Consult your local Forest Service or Department of Forestry for
these guidelines.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.

&&

$$
SYNOPSIS...SH/WP
NEAR TERM...BMG/WP
SHORT TERM...PW
LONG TERM...PW
AVIATION...BMG/WP
FIRE WEATHER...BMG/WP