Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/17/25
Area Forecast Discussion
National Weather Service Bismarck ND
625 PM CST Thu Jan 16 2025
.KEY MESSAGES...
- Windy and colder Friday. Temperatures falling through the day,
with highs occurring in the early morning hours. 20 percent
chance for light snow.
- There is a chance of isolated snow squalls Friday morning.
- Very cold temperatures this weekend, and through early next
week, with life threatening wind chills.
- Temperatures warm to near average by the middle of next week.
&&
.UPDATE...
Issued at 618 PM CST Thu Jan 16 2025
Going forecast remains in good shape as winds continue to
gradually increase as the surface low is making its way over far
southeast Saskatchewan about to push into Manitoba. No changes
needed at this time.
&&
.DISCUSSION...
Issued at 345 PM CST Thu Jan 16 2025
Today will be the last day of temperatures above freezing. We
currently are sitting under a slight ridge aloft with a thermal
ridge at 850mb, at the surface a ridge is present. High clouds
have been moving in all day on the edge of the next system and
wave.
An arctic cold front will violently sweep through the region,
dropping temperatures and creating very windy northwest winds.
This front is the off an Alberta clipper that will just graze
the International Border. Light snow is possible with the cold
front. Timing for the frontal passage is Friday morning around
12z, however the pressure gradient off the low will move through
overnight. Therefore the winds will increase overnight, and a
Wind Advisory has been issued starting at Midnight CT tonight.
Winds will gust around 40 mph overnight, then when the front
kicks in with strong cold air advection, winds could gust up to
50 mph. The fast moving cold front will be through North Dakota
and into South Dakota by 18z.
Another concern with this front is snow squalls. There is low
level moisture, some instability, and convergence leading to a
high parameter for snow squalls. Unfortunately The RAP and the
NAM have different placement but similar timing. The RAP only
has the southwest lit up between 13 and 21z. The NAM is has
high parameter values entering the northwest at 09z and then
along the west/east front through 20z. With how fast the front
is moving the threat window seems small.
Sunday and Monday morning will be very cold. Lows around 20
below with life threatening wind chills at 50 below. Aloft
strong northernly flow will lead to this. There is very high
confidence in needing a warning and or advisory Saturday
through Tuesday morning. We will let this strong wind event
start before issuing Cold Weather products, so stay tuned.
Next week the flow changes to a slight ridge leading to
temperatures back in the 20s mid week. There are slight chances
(20%) as a weak clipper could spin through on Wednesday and
Thursday.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 618 PM CST Thu Jan 16 2025
Winds will be on the increase as a surface low slides through
southern Saskatchewan and Manitoba into Ontario. As this low
progresses, winds will become westerly, switching northwesterly
behind a strong cold front. By Friday morning, winds gusting
around 45 knots are expected across western and central North
Dakota. VFR conditions will continue through this evening, with
MVFR ceilings sliding in behind the cold front Friday morning.
In addition, low snow chances will develop on Friday. Given the
low confidence for snow at each individual TAF site, will not
mention for now, but if snow were to occur visibility could
become quite poor for brief periods of time given the strong
winds.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from midnight CST /11 PM MST/ tonight to 8 PM
CST /7 PM MST/ Friday for NDZ001>005-009>013-017>023-025-
031>037-040>048-050-051.
&&
$$
UPDATE...JJS
DISCUSSION...Smith
AVIATION...Smith
Area Forecast Discussion
National Weather Service Charleston SC
1010 PM EST Thu Jan 16 2025
.SYNOPSIS...
High pressure will prevail through the week. An area of low
pressure and associated cold front will impact the region this
weekend. Another low pressure system could impact the region
early to mid next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Tonight: Tricky forecast regarding the hourly and minimum
temperatures, driven entirely by how much wind is ongoing. For
example, as of late Thursday, where winds have gone calm,
temperatures are in the 30s. Where there is still some mixing
due to a 25-30 kt low level jet moving through, temperatures
are in the 40s. Expect temperatures to bounce around some due to
a light SW and W breeze, before more places go calm by morning
with a relaxed gradient around high pressure near the
Appalachians, and in wake of the low level jet. For actual lows
will mainly have lower and middle 30s inland, upper 30s and a
few lower 40s closer to the coast.
Satellite images still showing a few fires in and near parts of
the area. Utilizing the HRRR and RAP, and a continuation of
some mixing through much of the night, there might be smoke
noticed in some places. There has not been any visibility
reductions per surface observations, but with the formation and
strengthening of the nocturnal inversion overnight, there might
be a few places with visibilities lowering at the surface.
Lake Winds: Winds across Lake Moultrie will increase again
through 3 AM, as a 25-30 kt low level jet passes through. Some
guidance suggests conditions could get close to advisory
thresholds, and we continue to monitor. For now though no
advisory has been issued.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
High pressure will give way to an approaching cold front
Saturday as a series of northern stream shortwaves propagate
across the northern CONUS. Rain chances will increase quickly
Saturday ahead of the cold front as building moisture
characterized by PWATs >1" combine with forcing generated by
passing southern stream shortwave energy and the left exit
region of a power 150 kt subtropical jet. It appears most areas
will receive a solid 0.75-1.50" inch of rain with this system
and categorical pops 90-100% were maintained. Flooding is not
anticipated to be an issue. Rain chances will slowly diminishing
Saturday night into Sunday as the front pushes offshore. Highs
each day will warm into the upper 50s/lower 60s away from the
coast with overnight lows dropping into the mid-upper 30s Friday
night with upper 40s/lower 50s Saturday night.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
There remains much uncertainty the system that will impact the
region during the mid-week as a cold, arctic airmass settles
over the region. What is known is there is high probability for
temperatures to average well below normal levels for mid-January
with highs both Tuesday and Wednesday likely remaining solidly
in the 30s with minimum wind chills falling into the 10-20
degree range at night. This is well within Cold Weather Advisory
criteria (11-20 degrees). In fact, there are signals that some
locations could see wind chills drop below 10 degrees which is
dipping into Extreme Cold Warning territory (10 degrees or
colder).
What is more uncertain is how the precipitation pattern will
evolve Monday night through Wednesday morning when temperatures
will be at the coldest. Much will be dependent on how far south
and offshore low pressure tracks off the Southeast U.S. coast in
response to an impressive upper trough propagating across the
eastern CONUS. Given the amount of cold air in place, it remains
quite reasonable that varying degrees of accumulating winter
weather could occur over Southeast South Carolina and Southeast
Georgia with specifics on p- types, intensity and possible
accumulations remaining highly uncertain this far out. While a
few of the operational runs of the various long-term guidance
have trended drier over the past few cycles, many of their
accompanying ensemble counterparts remain quite wet and cold.
All number of outcomes remain plausible ranging from little to
no precipitation to a full blown winter storm with significant
impacts; however, net accumulating snow and freezing rain
probabilities are creeping up with each forecast cycle. The
official forecast remains fairly steady state with some minor
upward adjustments in pops, showing various degrees of a mix of
snow, freezing rain and rain in the Monday night to Wednesday
morning time frame. Right now, sleet looks the be the least
likely p-type to occur.
Most of the precipitation should end Wednesday morning. There
are signals that a weak wave of low pressure could develop
offshore Wednesday night into Thursday and with temperatures
still cold, some lingering pockets of freezing rain could occur.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
VFR conditions will prevail at KCHS, KJZI, and KSAV through 00Z
Saturday.
Extended Aviation Outlook: Flight restrictions are likely
Saturday as widespread rains move through in association with a
cold front. The risk for restrictions in low vsbys and ceilings
will return Monday night into Wednesday morning as a potential
winter storm impacts the region. There is a chance for freezing
or frozen precipitation impacting all terminals during this
time.
&&
.MARINE...
Tonight: We maintain the Small Craft Advisories for the South
Carolina Atlantic waters and for the outer Georgia waters until
late. We considered dropping the advisory on the lower South
Carolina waters since conditions of late have been below
advisory thresholds. However, with some stronger geostrophic
winds and a little weak cold advection, winds could strengthen
again. In general there will be W or WSW winds up near 15 or 20
kt and gusty most of the night, turning more toward the WNW and
dropping about 5 kt or so late in wake of a surface trough. Seas
will be 4 feet or less throughout, except for a few 5 footers
over parts of the distant Charleston County waters and beyond
50 nm off the Georgia coast.
Friday through Tuesday: Northwest winds will surge behind a
cold front Sunday night with speeds reaching 15-25 kt with gusts
to 30 kt. Small Craft Advisories are likely during Sunday night
into Monday morning. Seas will peak 3-5 ft over the nearshore
waters out 20 NM and 4-6 ft over the Georgia offshore waters out
20-60 NM. Another surge will occur Monday night into Tuesday as
the pressure gradient tightens between inland high pressure and
a developing low offshore. North to northeast winds 20-25 kt
with gusts to 30 kt will occur during this time with seas 2-4 ft
within 20 NM and 4-6 ft over the Georgia offshore waters out
20-60 NM. Some winter precipitation could fall over the coastal
waters Monday night into Tuesday.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 4 AM EST Friday for AMZ350-352-374.
&&
$$
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
Area Forecast Discussion
National Weather Service Grand Forks ND
634 PM CST Thu Jan 16 2025
.KEY MESSAGES...
- Strong winds are expected on Friday. Potential winter impacts
range from brief whiteout conditions due to snow showers to
more sustained blizzard conditions or even snow squalls.
Uncertainty is tied to coverage of snow showers and
blowability of snow pack.
- Hazardous wind chills this weekend through Monday. Wind chills
of -40 or lower are expected across North Dakota and northern
Minnesota.
&&
.UPDATE...
Issued at 633 PM CST Thu Jan 16 2025
Pretty much in a lull on this evening shift before the action
begins late on the midnight shift. There are some echoes on
radar across the northern Red River Valley into adjacent areas
of northwest Minnesota. However there is nothing reaching the
surface, with most observations showing only mid level clouds
(10,000 feet or so). Temperatures are quite mild, and these may
actually rise a little going into the night. Seeing upper 30s to
low 40s temperatures back in the Minot to Bismarck corridor. As
winds turn to the west by mid to late evening, these warmer
temperatures may shift eastward, although they will likely not
be as warm as they are now.
Did notice that Environment Canada has a Blizzard Warning for
southern Manitoba (and Winnipeg) for the Friday event. For our
area, we are under a Winter Weather Advisory. There are a lot of
questions about the state of the snow on the ground, what areas
may or may not have a crust, the potential for snow squalls,
and what 50+ mph winds will do it. Also, there may be some dirt
particles lofted as well, but that is hard to know too. The snow
that could get lofted over our FA Friday may come from southern
Manitoba, even up toward the Manitoba Lakes region, where we
just don`t know what the state of the snow is like. We are
anticipating wind directions to be about 340 degrees (NNW),
which does give a long fetch across the Manitoba Lakes, which
could stretch down into the Red River Valley. So there are still
a lot of unknowns.
&&
.DISCUSSION...
Issued at 238 PM CST Thu Jan 16 2025
...Synopsis...
Fairly quiet for the moment under northwesterly flow, but a
positively tilted trough will start digging down out of Canada
tonight, coming into the Northern Plains and settling in with a
broad area of low heights over the central CONUS through this
weekend and early next week. Northwesterly flow by mid-week
should allow for some moderation by the end of the period.
...Arctic front and snow showers Friday...
While temperatures today are not as warm as yesterday with high
clouds around and have stayed in the 20s, there will be a strong
warm tongue tonight ahead of the cold front. Some of the high
resolution models such as the RAP and HRRR actually have
temperatures rising overnight and reaching above freezing which
would lock in more of the snow pack. Not quite sure about that
but definitely will see a non-diurnal temperature curve
tomorrow as the Arctic cold front starts to move into our
northwestern counties tomorrow morning. The front will shift
winds to the northwest and drop temperatures as is usual for
such features. Snow squall parameter along the front is around
3-5, so could see some well defined snow showers that reduce
visibility for a period and have started messaging to improve
education about the phenomenon. Even after the initial front
passes and snow squall parameter decreases, there will still be
some steep lapse rates and unidirectional boundary layer shear
that could help horizontal convective rolls develop. These HCRs
could be fleeting or stick around, and any that produce
additional snow will reduce visibility. While much of the snow
pack is not blow able to very warm recent temperatures, there
are some spots, particularly near the Langdon area as well as
just east of the Red River in the MN side of the Valley where
snow could be a bit more loose. A medium chance of more
widespread blowing snow impacts in those areas so will have to
keep a close eye out. For now, have a winter weather advisory,
and will upgrade as needed for higher impacts or any snow
squalls if they develop.
...Arctic cold weekend into next week...
After the trough on Friday, a 1040 to 1050 mb high pressure
system settles from Canada into the Plains states. Another
reinforcing shortwave coming down from Canada on Monday will
help push the center of the surface high further east, and that
looks like the coldest day with highs in some areas not getting
out of the teens below zero. Apparent temperatures look to be
down into the -40 or below range, so will continue to message
hazardous cold.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 546 PM CST Thu Jan 16 2025
Besides low level wind shear, no impacts overnight with VFR
conditions. Things change early Friday morning, as an
approaching cold front pivots winds to the northwest. Winds will
be strongest in the late morning through the afternoon, with
gusts of over 40 knots at times at KDVL, KGFK, KFAR and KTVF.
Along the leading edge of the front, brief but heavy snow may
occur. Therefore, added a TEMPO group showing reduced visibility,
timed out as best as possible from north to south as the front
passes through. Note, visibility may be worse at times then
this TEMPO group shows, depending on the strength of the snow
squall feature, but due to the low predictability of snow
squalls, did not want to lower visibility further. BLSN will
continue into the afternoon, reducing visibility. How severe
these reductions will be depends on how much snow continues to
fall, and if old snowfall can loft. Conditions improve in the
evening as winds slowly decrease and any remaining falling snow
ends.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Winter Weather Advisory from 9 AM to 9 PM CST Friday for
NDZ030-038-039-049-052-053.
Winter Weather Advisory from 6 AM to 9 PM CST Friday for
NDZ006>008-014>016-024-026>029-054.
MN...Winter Weather Advisory from 9 AM to 9 PM CST Friday for
MNZ001>003-005-008-013>015-022-027-029-030-040.
Winter Weather Advisory from 6 AM to 9 PM CST Friday for
MNZ004-007.
&&
$$
UPDATE...Godon
DISCUSSION...JR
AVIATION...Rafferty
Area Forecast Discussion
National Weather Service Indianapolis IN
926 PM EST Thu Jan 16 2025
.KEY MESSAGES...
- Brief reprieve from sub-freezing temperatures on Friday with highs
in the mid 30s to near 40.
- Warm up to end the work week, with rain likely Friday night and early
Saturday. Snow will mix in with the rain by Saturday morning
with a possibility for very light accumulations
- Bitterly cold air is expected Sunday through the middle of next
week with multiple nights of subzero lows likely. Single digit highs
expected in most areas Monday and Tuesday
&&
.FORECAST UPDATE...
Issued at 926 PM EST Thu Jan 16 2025
- Becoming partly cloudy overnight; Fog Possible
Surface analysis this evening shows a ridge of high pressure over
the Mississippi Valley. This was allowing light westerly flow across
Central Indiana. GOES16 shows extensive cloud cover over Central
Indiana, however a back edge to the cloudiness was found over
northern IL and SE Wisconsin. Dew point depressions across the area
were generally less than 5F. Aloft ridging was in place over the
northern plains, with continuing northwest flow spilling into the
Ohio Valley.
Overnight, the surface ridge is expected to push eastward, allowing
more of a southwest to southerly flow to develop. As this builds
across Indiana, it should help to nudge the pesky strato-cu across
the area farther east, as clearing skies across Central IL and WI
build east. The NW upper flow will continue to allow the passing of
some high cloud overnight. Thus overall, becoming partly cloudy will
work well.
Clearer skies across southwest Central Indiana will allow
temperatures to fall quicker there overnight. Given the expected
cooler low temperatures, better chances for fog development will be
expected there. Models continue to suggest warm air advection
overnight. Given our snow pack across the area, this will be another
favorable element for fog. Thus will include some patchy freezing
fog across the forecast area overnight due to this potential.
Freezing fog does have the potential to create slippery surfaces.
&&
.SHORT TERM (This evening through Friday)...
Issued at 301 PM EST Thu Jan 16 2025
A brief break from the sub-freezing temperatures will only stick
around for today and tomorrow before another arctic blast engulfs
the region. The arctic airmass that had been in place for much of
the week is being eroded by slight warm air advection aloft and
breezy westerly winds. ACARs soundings from around the region show a
stronger low level warm nose than what the RAP suggests around 1 km
agl with a shallow mixing layer from the surface to about 0.5 km
agl. A stronger surface pressure gradient over the area and shallow
mixing into the 30 kt LLJ has resulted in westerly surface winds
today of around 15 mph with gusts upwards of 25-30 mph at times.
Despite low stratus across much of Indiana this afternoon, mixing
and windy conditions have helped "warm" areas along and south of the
I-70 corridor to the freezing mark and mid to upper 30s in southwest
Indiana.
Breezy conditions are expected to diminish after sunset tonight as
warm air advection aloft and diurnal cooling strengthen the low
level inversion and mixing shuts off. Surface flow will be fairly
light most of the night, but turns southerly towards dawn around 4
to 8 mph. Relatively warmer air flowing over the cold snowpack may
result in patchy fog, particularly for areas that end up clearing
out with temperatures falling closer to the dew points. Confidence
is lower on if clearing will take place overnight as satellite
imagery does show another large area of stratus pushing into
Illinois from the NW which could overspread Central and North
Central Indiana later tonight. Best chance for clearing and some
patchy fog tonight looks to be along and southwest of I-74. Lows
tonight should fall back below freezing into the low to mid 20s for
most locations.
Another relatively "warmer" and breezy day tomorrow with much
stronger warm air advection aloft. Forecast soundings look similar
to today with such a strong warm nose around 1 km agl and denser
colder air stuck at the surface. The boundary layer should be a bit
drier tomorrow as compared to today with less of a threat for low
clouds during peak heating hours of the day, so expect increased
sunshine to help most locations, even with snow pack, to rise into
the mid 30s to near 40.
Will have to watch dew points and wet bulb temperatures tomorrow as
they could have a big impact on how much snow melt occurs, which in
turn may have an affect on certain forecast aspects later this
weekend and into next week. If dew points and wet bulb temperatures
remain at or below freezing, despite surface temperatures above 32,
melting of the snowpack will take much longer to occur. Any
remaining snowpack after Friday evening`s rain could lead to icy
surfaces during the next arctic blast and colder overnight lows.
&&
.LONG TERM (Friday night through Thursday)...
Issued at 301 PM EST Thu Jan 16 2025
As mentioned in the short term, the presence of a thermal ridge
Friday will help provide a brief thawing as daytime highs push well
above freezing. This should help reduce the snowpack of central
Indiana, prior to the start of precipitation, but the biggest
question is, how much? Currently, we are expecting may locations
south of I-70 and west of I-74 to have a near zero snowpack by
Friday evening. Elsewhere, higher uncertainty resides. This is
mostly due to the lack of surface moisture mitigating sublimation,
despite the warmer air temperatures.
This all matters due to the emergence of strong isentropic lift
Friday night with precipitation expected to begin between 8PM and
12AM across central Indiana. Any areas that have no snowpack will
start and stay as rain through most of the event (could be slight
mixing due to dynamic cooling Saturday morning). Areas that remain
within a snowpack could lead to greater wetbulb cooling with
slightly cooler surface temperatures allowing for an earlier mix,
and potential for light, slushy accumulations. The greatest threat
for this will be over far NE portions of central Indiana.
Colder air will advect into the region Saturday morning, allowing
for a quick chance of a rain/snow mix of most of central Indiana.
This should push off to the SE quickly as CAA arrives behind the
system. In total, SW of I-74 should receive a tenth of an inch or
less, with a gradual gradient towards 0.5 in or less in far NE
central Indiana.
Yet another extended stretch of bitterly cold temperatures will
arrive Sunday through most of the work week next week. An
exceptionally strong corridor of cold air advection will work to
push very strong surface high pressure into the Ohio Valley,
potentially greater than 1050mb. This CAA will also work to compress
the midlevels leading to a very shallow troposphere and arctic air
mass over the region; this will likely result in the coldest weather
yet for this winter by Monday and Tuesday.
High temps will revert back to the teens by early next week, with
single digits likely Monday and potentially Tuesday. The pattern
supports multiple subzero nights early next week as well, although
what is left of the snowpack after the rain Friday night and early
Saturday will factor into just how low those temperatures will be
able to go.
&&
.AVIATION (18Z TAF Issuance)...
Issued at 1246 PM EST Thu Jan 16 2025
Impacts:
- MVFR ceilings and wind gusts 18-24KT from 280 deg through this
evening
- Slight chance for fog tonight, with patchy dense fog possible.
Discussion:
Latest satellite imagery shows MVFR stratus pushing southeast
through Central Indiana associated with a weak mid level disturbance.
Latest IND ACARs sounding indicates a stronger low level inversion
that what hi-res guidance suggest for early this afternoon, so
expect lower MVFR stratus to persist under that inversion for at
least the next several hours, especially at KIND and KLAF. Despite
the inversion, gradient winds are strong enough to limit overall low
level wind shear. Still some slight shear to mention as surface
winds are from 260-280 gusting to 20-25 kts and LLJ winds around
2000 ft agl are from 280-300 around 30-35 kts. Not enough to mention
it in the TAF, but worth mentioning it here. Any threat for LLWS
should diminish after sunset this evening as the LLJ and surface
winds both weaken considerably.
Lower confidence in high fast MVFR cigs will lift or clear out
tonight as upstream satellite imagery and observations show a more
extensive area of MVFR stratus in Wisconsin and Iowa pushing
southeast towards Indiana. Guidance does show a rising trend in cigs
tonight, but confidence on that actually occurring for KLAF and KIND.
Tonight, as skies clear in the southern half of Indiana and winds
turn back to the south/southwest, some advection fog may be possible
over the remnant snowpack as warmer air continues to move into the
area. Guidance is struggling to handle this, but will include a
6SM/BR/BCFG mention for now as there may be some potential for at
least patchy dense fog as well.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Puma
SHORT TERM...CM
LONG TERM...Updike
AVIATION...CM
Area Forecast Discussion
National Weather Service Marquette MI
623 PM EST Thu Jan 16 2025
.KEY MESSAGES...
- Northwest lake effect snow gradually tapers off tonight.
Additional snow accumulations are expected to be less than an
inch, although, an additional 1-2 inches is possible in Luce
county eastward.
- Dangerously cold arctic air settles into the area this weekend
into early next week, leading to temperatures remaining
subzero from Saturday night through at least Tuesday morning
over interior western Upper Michigan. Much of the rest of west
and central Upper Michigan may see temperatures fail to rise
above zero on Monday and maybe Tuesday.
- Homeowners and property managers should take action now for
this cold period, especially if past very cold periods have
yielded impacts. Ensure your Winter Car Survival Kit is up-to-
date. This weekend through Tuesday, limit time outdoors for
you and your pets, and check on vulnerable neighbors.
- Frequent whiteouts are expected in the northwest wind snow
belts Saturday through Tuesday morning due to the falling snow
being a fine, powdery type snow that is highly effective at
reducing . Expect very hazardous driving conditions in the
lake effect snow areas.
- No widespread, significant snowfalls for Upper MI through next week.
Nearly all of the snow that occurs will be lake effect driven.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 302 PM EST Thu Jan 16 2025
Afternoon RAP analysis and water vapor imagery reveal troughing
nudging into the Upper Great Lakes and drier low level air making an
eastward trek across Lake Superior. This is actively working to
diminishing NW lake effect snow across the forecast area, where the
west half has been dry the last several hours. Meanwhile, light lake
effect snow showers are ongoing across the east half of the UP and
will continue through the evening. Into tonight, dry air will
continue to eat away at lake induced inversion heights, tapering off
LES across the east before the surface ridge axis presses into the
UP, backing winds to the SW and kicking any remaining showers
offshore. Overall, snow accumulations through Friday morning are
expected to remain low, generally less than an inch across the east-
central, though Luce county could pick up another 1-2" considering
the far east will hold onto low-level moisture the longest. Lows
tonight will dip into the teens across the interior to near 20F
along the lakeshores.
Upstream, a clipper is forecast to dig into the Upper
Great Lakes and send a sub-990mb sfc low north of Lake Superior
through Friday. Isentropic uplift noted around the ~290k theta sfc
Friday morning could touch off some light snow showers across the
west-central UP in the AM hours, however forecast soundings show a
stout dry layer below 700mb, which will be difficult to overcome;
thus PoPs have been capped to around 20%.
Otherwise, south-southwest winds will be on the increase early
Friday morning coinciding a 40-45kt low-level jet nosing into the
west-central UP. Areas susceptible to strong downsloping along the
Lake Superior shoreline in Marquette and Alger counties could see a
gusty morning with sfc winds upwards of 35-40 mph (>75% chance).
&&
.LONG TERM /FRIDAY THROUGH THURSDAY/...
Issued at 506 PM EST Thu Jan 16 2025
Medium range model guidance remains in excellent agreement on the
large scale surge of arctic air into the U.S. this weekend into
early next week. This surge of arctic air will be driven by a
building ridge over the ne Pacific that becomes highly amplified
northward thru Alaska/nw Canada into the high Arctic over the
weekend, forcing a significantly deepening trof downstream across
central to eastern N America. Negative height anomalies at 500mb in
this trof settle at ~320m (2.2-2.6 sigma) over WI on Mon. Over the
last 24hrs of model runs, ensembles have settled on 850mb temps
dropping to -30 to -31C into western Upper MI in the core of the
cold air as it reaches Upper MI. 850mb temps that low at this time
of year very easily support 2m temps remaining subzero during the
daylight hrs across interior western Upper MI and likely thru much
of central Upper MI as well. In addition, with 850mb temps at -30C
to -31C at lowest, would expect temps during the daylight hrs over
interior western Upper MI (generally Ironwood to Iron River area) to
struggle to get above -10F Sun/Mon, Mon in particular as the core of
the coldest air passes on that day, leading to the coldest day fcst
area wide. Once temps fall blo 0F over interior western Upper MI Sat
night, they won`t rise above 0F until sometime Tue aftn at the very
earliest, but it seems more likely now that it will be late Wed
morning before that happens. With the exception of areas from
Menominee to Escanaba, Manistique and Newberry, and along the Lake
Superior shore where w to nw winds are onshore, much of the rest of
the fcst area may remain blo 0F Mon and potentially Tue. Min temps
will range down thru the negative teens and -20s F away from Lake
Superior. Temps will even fall subzero to Lake Superior, except
where w to nw winds are onshore. There is the potential for a
morning or two with air temps falling to or blo -30F in Iron County,
maybe Gogebic County, but that will depend on whether sfc winds
largely decouple. Seems unlikely, but Sun night and Mon night would
be the nights to watch. A few record low min and record low max
temps may be set across Upper MI with this arctic outbreak.
Homeowners and property managers who have had issues with water
pipes freezing during periods of very cold conditions should make
preparations now. Areas that have very little snow cover could also
become at risk for freezing of water supply lines early next week as
ground frost depths deepen rapidly.
Fortunately, winds won`t be strong to really drive wind chills down
during this the arctic outbreak. Nonetheless, the cold will be
dangerous, and expect conditions to warrant cold weather advisories.
A few extreme cold warnings will be possible interior w. Even light
winds could result in conditions feeling like -20 to -40. These
conditions can result in hypothermia and frostbite in less than 30
minutes. Anyone with outside plans in this period should limit time
outside. Everyone is encouraged to ensure their Winter Car Survival
Kit is up to date. Check on vulnerable neighbors and limit outdoor
time for pets.
As for pcpn, this pattern will not support any widespread,
significant snowfalls for Upper MI through next week as only a few
clipper type waves will generate some brief periods of -sn. So,
snowfall will be almost exclusively lake effect driven. While the
arctic air arriving over the weekend/early next week will lead to
extreme overlake instability, the cold will also suppress the DGZ
toward the sfc or eliminate it altogether, leading to a fine/powdery
type snow (low SLR) that does not accumulate as efficiently. On the
flip side, this type of snow is highly effective at reducing
visibility, leading to frequent whiteouts in snow showers. This type
of snow is also easily kicked up on roads by vehicles, leading to
mini whiteouts trailing vehicles. Travel in the areas affected by nw
flow LES Sat thru Tue will be very hazardous due to poor visibility.
From Tue onward, flow across N America deamplifies, but there will
continue to be some degree of ridging in the mean over the ne
Pacific/adjacent N America forcing troffing in central and eastern N
America. The deamplification will allow for moderation from the
early week bitter cold, but the pattern will still support the
potential for colder air to at least graze Upper MI with the passage
of clipper type shortwaves. Expect temps on most days during the
last half of next week to be blo normal.
Beginning Fri, a clipper shortwave will pass across the area. This
wave will initiate the start of the arctic air surge. WAA/isentropic
ascent ahead of the wave will need to overcome drier air as that
ascent overspreads the area late tonight thru Fri morning. Models
are split on whether that will occur, but sufficient saturation will
occur deeper into the retreating colder air where it is easier to
achieve. Thus, will hold onto chc pops over the eastern fcst area in
the morning. Any snow accumulation will be less than 1 inch. Bigger
fcst concern is wind. Pres falls will pass across the area in the
waa regime with the center at 6-8mb/3hr passing just n of Lake
Superior. The resulting isallobaric wind will be aligned with the s
to sw gradient wind and thus enhance the wind. Wind direction will
be particularly favorable from the downslope areas of Marquette
County into the eastern fcst area. Given that HRRR/NAM/GFS fcst
soundings show potential to mix to 40-50kt winds for a few hrs and
considering the isallobaric enhancement, will hoist a wind advy for
Marquette/Alger counties for gusts up to 50mph Fri morning until
about mid aftn (13z-20z). In reality, peak winds will likely occur
in a 2-3hr period, so the advy timing runs a little long. Later
shifts will need to consider adding Schoolcraft and Luce as 180-190
wind direction is an ideal direction for strong winds there. Fcst
reflects 40-45mph gusts in that area for now. Any loose snow will
lead to blowing/drifting snow on roads. Cold front that passes late
Fri aftn/evening will be followed by incoming 6-9mb/3hr pres rises,
bringing another round of stronger winds, this time nw winds to the
Keweenaw and to lakeside locations from Alger County eastward. Based
on mixed layer winds in fcst soundings, expect 40-50mph gusts, maybe
peak up to 55mph on the Keweenaw. Will hold off on headline for
these winds given the late aftn/evening time frame. High temps on
Fri should reach the low/mid 30s F.
Cold fropa will initiate LES and lead to progressively colder air
flowing into the area thru the weekend on predominantly nw low-level
flow. Temps will fall thru the day on Sat as 850mb temps fall from
just after midnight Fri night readings of around -10C e to -15C w to
to around -22C e to -25C w by Sat evening. By sunset Sat, temps will
be nearing 0F w to around 10F above e. The increasingly colder air
surrounding the lake will progressively strengthen lake induced
thermal troffing, leading to winds developing an offshore component,
particularly off of nw WI, off of Marquette County and off of
Ontario along the e side of Lake Superior. This will favor enhanced
convergence into Ontonagon/southern Houghton counties and also into
Alger/Luce counties. Expect LES to be most persistent/heavier in
those areas. However, by later Sat and thru Tue, the cold will
suppress the DGZ to near the sfc or eliminate it altogether, leading
to a fine/powdery type snow that does not accumulate as efficiently
as typical LES. Initial thoughts are that snow accumulations will
end up in a 2-4 to locally 6 inch range on Sat before the arctic air
largely eliminates the DGZ. Then, a general 1-3 to isold 4-5
inches/12hr range Sat night thru Tue. The higher amounts are more
likely in eastern portions of Alger into Luce Counties due to longer
fetch and because the offshore wind component off of Ontario often
leads to particularly strong low-level convergence. In fact, given
the magnitude of the cold and the not particularly strong low-level
gradient wind fields as we get into Sun thru Tue, easterly winds may
push out a good distance over eastern Lake Superior at times,
converging with the wnw/nw winds over the lake. That may boost snow
amounts more than previously mentioned. Will be something to monitor
as we get closer to that time frame. Bigger issue with the snow will
be whiteouts as previously discussed. Winds will be stronger on Sat,
leading to blsn, but during the coldest period Sun into Tue, winds
won`t be particularly strong, gusting to around 25mph near the Lake
Superior shore and Keweenaw and up to around 20mph elsewhere. Even
so, the fine/powdery snow will be easily lofted by these winds to
further reduce the already very poor vis from the falling snow.
Wind begin to back westerly Tue with onset of waa, shifting LES to
mainly the Keweenaw over the w and closer to shore over the e.
Clipper type shortwave will pass at some point Wed/Thu to provide a
chc of -sn, followed by some LES.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 623 PM EST Thu Jan 16 2025
Dry air is slowly working its way into the area. MVFR conditions at
all sites will go VFR this evening and will stay that way into
Friday morning. Friday, a low pressure passing north of Lake
Superior will increase south-southwest winds in the morning where
gusts upwards of 25-30kts are possible at all sites through the
afternoon. The uptick in winds aloft will also bring potential low
level wind shear impacts at IWD. MVFR conditions will come back in
by Fri afternoon. CMX will have some blowing snow with the gusty
winds where it could get down into the IFR category.
&&
.MARINE...
Issued at 506 PM EST Thu Jan 16 2025
A couple of passing clippers will result in a strong pressure
gradient over the lake at times in this period, followed by
deepening arctic cold this weekend and early next week.
Ongoing nw winds to 20-30kt, strongest over eastern Lake Superior
will fall briefly to 20kt or less by late evening as sfc high pres
ridge quickly passes. Winds then increase again late tonight into
Friday as next clipper system approaches. S to sw gales are likely
by Fri morning as winds are enhanced by strong pressure falls
passing over the area with the max pres falls passing by just n of
the lake. Gales will reach 40-45kt across the e half, including a 15-
25pct chance of peak gusts reaching storm force. After the cold
front associated with the clipper crosses the lake Fri aftn/night,
nw gales will develop as colder air flows into the area with winds
enhanced by incoming pres rises. Another high end gale will occur
with the nw winds, including a 15-25pct chance of peak gusts
reaching storm force. These stronger winds will diminish during the
day Sat, but increasingly colder air flowing over the lake will
support 20-30kt winds. There is also some local gale potential where
wnw/nw winds over the lake converge with winds locally altered by
very cold air flowing off of the land. There area some indications
for another clipper middle of next week, which could increase winds
again.
The increasingly colder air arriving over weekend will support ice
accretion from freezing spray. Expecting moderate to heavy ice
accretion rates at times.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Wind Advisory from 8 AM to 3 PM EST Friday for MIZ005-006.
Lake Superior...
Gale Warning from 7 AM EST /6 AM CST/ Friday to 1 PM EST /noon
CST/ Saturday for LSZ162-240>251-263>267.
Lake Michigan...
Gale Warning from 9 AM to 7 PM EST Friday for LMZ221-248-250.
&&
$$
SHORT TERM...BW
LONG TERM...Rolfson
AVIATION...07
MARINE...Rolfson
Area Forecast Discussion
National Weather Service Blacksburg VA
935 PM EST Thu Jan 16 2025
.SYNOPSIS...
Front pushes east to the coast this evening with snow showers
over the mountains and gusty winds across most of the area
through early overnight. High pressure will expand to cover the
Mid- Atlantic Friday. A large storm system will bring
widespread precipitation Friday night into Saturday in advance
of an Arctic airmass that will arrive on Sunday.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 920 PM EST Thursday...
Key messages:
1) Winter Storm Warning downgraded to Advisory for r Western
Greenbrier tonight for up to 2 inches of additional snow.
2) Winter Weather Advisory cancelled for Mercer and Summer
Counties.
3) A Wind Advisory is in effect for much of the Blue Ridge
tonight.
Have dropped the Winter Storm Warning to an Advisory for western
Greenbrier as calls made up that way show only a dusting to no
more than an inch have fallen so far for this evening, which we
were expecting more with the warm front, and now only snow
showers will bring maybe 2 inches over the northwest parts of
Greenbrier as the upper shortwave is already pushing away and
there is no good lake connection to be had, with winds turning
more west as the night progresses. Further south, no more than a
dusting expected so dropped the advisory for Mercer and Summers.
Winds will be strongest from now until midnight, then should see
a diminishing trend overnight. No changes to the wind advisory.
Previous discussion...
The snow expected with the warm front ahead of the clipper
system was a no-show for our area through the afternoon, as main
axis of moisture stayed further north. Will be relying more on
upper disturbance this evening and upslope, which for now does
not seem it will be enough for warning criteria. However, some
low level instability may allow for heavier snow showers, so for
now, will leave headline as is.
Best low level jet arrives by 11pm, then letting up toward 4am,
so no changes to the wind advisory.
Previous discussion...
Satellite imagery indicates sunshine for much of the lower Mid-
Atlantic, with southwesterly winds in place ahead of an
approaching upper level disturbance. The disturbance will move
across the mountains this evening shortly after sunset,
resulting in upslope snow showers affecting mainly portions of
southeast West Virginia into the Alleghany Highlands and the New
River Valley. Still running with a Winter Storm Warning for
western Greenbrier County, where 4 to 6 inches of snow is
forecast, with locally higher amounts. Up to 3 inches remain in
the forecast for Mercer and Summers Counties, where a Winter
Weather Advisory remains in place.
The disturbance will also bring a brief period of strong winds
across the central Appalachians, bringing 45 to 50 mph gusts
across the higher ridges from Watauga County through the
southern Shenandoah Valley. The window for these winds are
short however as the disturbance moves quickly away to the east
overnight, and have therefore issued a Wind Advisory in effect
from 7 pm this evening through 4 am Friday.
Once the disturbance begins to exit to the east overnight, high
pressure will quickly fill in from the west. This will result
in decreasing wind speeds, in addition to diminishing mountain
snow shower activity and decreasing clouds as dawn approaches.
Upper level ridging passing across the region on Friday,
combined with sunshine and winds shifting from the south will
make for near-normal afternoon temperatures. Highs will range
from the mid 30s along the Interstate 64 corridor west of
Lexington, to the mid/upper 40s across the Piedmont.
Keeping an eye on an approaching disturbance
Short wave crossing through the long wave eastern United States
trough will move through the Mid Atlantic area today and tonight.
The best synoptic scale lift with the upper jet and positive
vorticity advection, followed by upslope lift will be in the 10AM-
10PM time frame. Enough liquid equivalent precipitation, around 0.5
inches and large enough snow ratios, roughly 15:1 to get snow
accumulations in southeast West Virginia of 2 to 8 inches. Some
locally higher amounts are possible in Western Greenbrier County.
Also models are suggesting some relative instability this afternoon
that may be enough for snow squalls or at least narrow bands of
heavier snowfall rates. Colder air aloft does arrive in the area
around that time. Biggest question is the amount of moisture. The
air mass is starting the day well below 0.25 inches of precipitable
water and some of the early snowfall may go into saturating the air
mass instead of accumulating. But, eventually the precipitable water
values are back up around 0.25 inches. Latest HRRR has the snow
reaching most of southeast West Virginia between 7AM and 10AM.
This feature goes by with the 500MB trough axis to the east by
Friday morning. Winds turn to the west and northwest tonight. The
low level jet increases this evening with the strongest 850mb wind
from 00Z/7PM to 06Z/1AM with good pressure rises, 5-8MB in 6 hours
at the same time. Will assess again today to determine if a Wind
Advisory is needed along the southern Blue Ridge. Wind speeds drop
off quickly by Friday morning. By then surface high pressure
directly over the central and southern Appalachians.
Upper ridging on Friday and more sunshine will result in
temperatures around normal. Stayed close to a NBM/LAV guidance blend
for highs and lows through this period.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 220 PM EST Thursday...
Key Messages:
1) Wintry mix of snow, sleet, and freezing rain expected
Saturday morning becoming mostly rain by afternoon.
2) Windy, becoming bitterly cold, with mountain snow showers
Monday into Tuesday.
A vigorous southern stream shortwave ahead of a deepening
eastern U.S. trough will move through the region Saturday
morning, bringing precipitation to the region. At the onset time
of this precipitation around daybreak Saturday, temperatures
will be in the mid 20s to lower 30s across the CWA. A weak warm
nose is evident in the model soundings suggesting that
precipitation will transition from snow, to sleet, to
potentially freezing rain in the southern parts of the CWA.
Temperatures are expected to rise above freezing by late morning
into the early afternoon allowing all precipitation to change
over to rain. The limited duration of frozen/freezing
precipitation and the limited QPF overall from having to
overcome an antecedent dry air mass, will limit ice/snow
accumulations. Nonetheless, could certainly see a scenario where
a Winter Weather Advisory will be warranted with later
forecasts for much of the CWA during the late Friday
night/Saturday morning time frame. Temperatures should top out
in the upper 30s to lower 40s by afternoon with just weak
wedging. QPF looks to be in the 1/4 to 1/3 inch range, thus an
inch or so of snow/sleet/freezing rain mixture will be possible
during the morning hours.
The passage of this initial short wave will quickly result in
further deepening of the upper trough across the eastern U.S.
and also bring the first surge of what will prove to be the
coldest Arctic air to visit this region in several years.
Precipitation along/east of the Blue Ridge will mostly end by
Saturday evening and transition to typical upslope snow showers.
On Monday, the first of two brutally cold surges of Arctic air
will settle over the area in the form of a 1044mb Arctic high.
This first surge will pale in comparison to the next midweek
surge. Look for a non-diurnal temperature trend on Monday with
strong cold advection all day as 850mb temperatures plummet from
-4C early in the day to nearly -20C by the end of the day.
/Confidence Levels in Forecast Parameters/
- Moderate to High Confidence in Temperatures,
- Moderate Confidence in Precipitation Probabilities,
- Moderate Confidence in Wind Speed, High Confidence in Wind
Direction.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 245 PM EST Thursday...
Key Messages:
1). Bitterly Cold with Dangerously Low Wind Chills Through the
Period.
2). Potential Snow Event Just Behind This Period...Need to Watch
Closely.
Truly one of the coldest air masses to visit the region in many
years will spread across much of the eastern U.S. during the mid
part of next week. Looking for 850 mb temperatures to range
anywhere from -20C to -25C from the Midwest to the Mid-
Atlantic to settle over the forecast area as a 1050+ mb surface
high drifts southeast out of Canada by midweek. A large core of
-30C temperatures is noted within the center of this frigid air
mass, larger than I have seen in several years. This will
eventually be very close to the CWA midweek.
Look for multiple days with highs well below freezing and lows
near to even below zero during the later half of the week. Plan
accordingly for some of the coldest temperatures of long
duration in several years. This will be colder than the spell
during Christmas 2022. Wind chills will be dangerously low
multiple mornings in a row.
Finally, keeping an eye on a potential winter storm for next
weekend. Will leave that discussion for later.
/Confidence Levels in Forecast Parameters/
- High Confidence in Temperatures,
- Moderate Confidence in Precipitation Probabilities,
- High Confidence in Wind Direction and Speed.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
As of 635 PM EST Thursday...
VFR for most of the area through the period. Exception will be
IFR to MVFR cigs and vsbys at BLF with snow showers through 12z,
with mainly MVFR at LWB. May see MVFR cigs at BCB as well
between 02-08z. West winds will pick up and gust 20-30kts across
the mountains between 02z-09z, with less wind in the LYH/DAN
area.
High pressure builds in bringing VFR back to the mountains and
lowering the wind speeds by midday Friday.
AVIATION OUTLOOK...
Clouds will increase again Friday evening as an approaching low
pressure system is expected to bring widespread precipitation
and poor flying conditions Friday night and Saturday across the
region. Sub-VFR conditions will persist through Sunday with
upslope snow showers in the mountains.
Monday and Tuesday will be unseasonably cold, dry and VFR.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Wind Advisory until 4 AM EST Friday for VAZ007-009>020-022>024-
032>035.
NC...Wind Advisory until 4 AM EST Friday for NCZ001-002-018.
WV...Winter Weather Advisory until 7 AM EST Friday for WVZ508.
&&
$$
SYNOPSIS...AMS/NF/WP
NEAR TERM...AMS/NF/WP
SHORT TERM...RAB
LONG TERM...RAB
AVIATION...AMS/NF/WP
Area Forecast Discussion
National Weather Service Tucson AZ
134 PM MST Thu Jan 16 2025
.SYNOPSIS...A weather system will be passing over the region
tonight bringing slight chance of showers mainly from Tucson
north and northeastward. Cooler temperatures return starting
tomorrow and persist through early next week.
&&
.DISCUSSION...The latest water vapor imagery, as of this writing,
show a closed off low located over Southern California to Baja
California. Southeast Arizona has a large swath of diffluence and
some low level clouds have recently developed southwest of Tucson.
This weather system will be moving northeast for the rest of today
and into night. The easterly breezes will start to shift to the
southwest by the middle of the afternoon once the low pressure
center comes more inland. The 12Z HREF radar reflectivity plots
have a a handful of the models with showers developing this
evening and moving the northeast. The showers are on the low end
and the better chances to receive showers will be northeast of
Tucson. The last 4 HRRR runs continue to show the rain showers
developing along northern portions of Graham and Greenlee
counties. With that, there are slight chances for rain showers and
mountain snow tonight.
Tomorrow and the weekend...The low pressure will help draw in
cooler air into the region. Temperatures will come down several
degrees starting tomorrow. There can be a some cold feeling mornings
across the region, Tucson being a few degrees above freezing on
Saturday and Sunday morning. There will be some westerly to
northwesterly breezes tomorrow, mainly in Graham, Greenlee, and
Cochise County.
Next week, the ensembles attempt show another change in pattern by
early next week, but there is still some uncertainty on the speed
and location of the system. This morning ensemble run shows a
decent amplified ridge along the western coast with a low
pressure center moving on shore. The ridge will likely absorb the
low and bringing some troughing in the intermountain west. There
is now a lean of 38% of ensemble members keeping the low north of
our region and keeping us fairly dry. It won`t be able to tap into
the better moisture sources in this scenario. This also presents
a challenge for temperatures with the ensembles disagreement of
the position of the system. Currently, there is a 10 degree
spread in the max temperatures and 8 degree spread in the min
temperatures for Tuesday to Wednesday. It is a quite a spread and
could mean it be way cooler or cool by the middle of next week.
With this forecast package, temperatures will be slightly below
normal by the middle of the week.
&&
.AVIATION...Valid through 18/00Z.
FEW clouds at or around 10K feet AGL and then becoming SCT-BKN
after 17/01Z. Another SCT-BKN cloud layer at or around 20k feet
AGL moving through area between 16/23Z until 17/06Z. There are 15-30%
chances for light showers (KTUS to the northeast) and mountain
snow showers in the White Mountains tonight from 17/02Z to
17/10Z. After 17/12Z, SKC until the end of the forecast period.
Todays afternoon winds will be easterly to southerly at 10-15 kts
with gusts up to 25 kts. By 16/22Z, winds will shift to the
southwest at similar speeds until 17/03Z. Overnight winds will
generally light and variable. Tomorrow morning, after 17/18z,
winds will return to westerly to northwesterly at 5-10 kts with
gusts around 20 kts. Terminals from KSAD to KDUG and east will see
stronger breezes in towards the end of the forecast period.
Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Dry conditions will prevail across much of
southeast Arizona the next 7 days, with a slight chance (15-30%)
of light precipitation from Tucson north to northeast tonight
into Friday morning. Low chances (10-15%) again on Monday through
Monday night (mainly towards the White Mountains). Southwesterly
winds through this afternoon with gusts up to 25 mph. Tomorrow, west/northwest
winds, especially in Cochise and Graham counties, at speeds of
15-20 mph and gusts to around 30 mph. 20-foot winds will be 15 mph
or less Saturday and Sunday, with increasing winds again by
Tuesday. Min RH values will be 12-20 percent in the valleys and
20-30 percent in the mountains through early next week.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
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