Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/10/19

Area Forecast Discussion

National Weather Service Gaylord MI

 945 PM EST Sat Nov 9 2019

.UPDATE...
Issued at 945 PM EST Sat Nov 9 2019

Brief period of precip-free wx in northern MI was, well, brief.
Low-level moisture has pooled along the cold front that is moving
into eastern upper MI. This has re-activated the lakes in a regime
of marginal instability, with some light snow that started at the
twin Saults at about 7 pm. This has diminished in intensity
somewhat, though MQT radar already showing a post-frontal streamer
poking into the Gd Marais area. There will be more, with
central/northern Chippewa Co being the primary target. Potential
for 1-2" in snow overnight in western Chip.

Ahead of the front, mid-level moisture associated with a shortwave
is increasing into northern lower. The strongest forcing with this
wave will slip just to our south. However, with the surface cold
front making steady progress to the se tonight, we will have
enough deep moisture to allow weak lake enhanced precip to
develop. Latest guidance suggests this will spotty at best, with
an uptick in coverage perhaps toward daybreak over the higher
terrain of northern lower. Will be reducing pops in northern lower
MI for much of the night.

Even as (initially) weak cold advection begins post-fropa, clouds
will temper/delay further temp falls. Min temps have been boosted
a bit in northern lower MI.

&&

.NEAR TERM...(Through Tonight)
Issued at 337 PM EST Sat Nov 9 2019

...Back into snow showers later tonight...

High Impact Weather Potential: Minimal through tonight. Some
accumulating lake snows by Sunday morning.

Pattern Synopsis/Forecast: Surface low pressure has slowly
migrated into northeast Lake Superior with much of the state
within some semblance of a "warm sector" this afternoon (0C H8
isotherm is nudging into western Lower Michigan per latest RAP
forecasts). Warm/dry air advection into the region has eroded a
good portion of the lower cloud cover particularly south of M-72
where there is a good amount of bonus sunshine. Lake cloudiness is
hanging on across northern Lake Michigan into the tip of the
mitt/Straits and eastern Upper Michigan...although precip has
substantially dwindled this afternoon.

Upstream, surface cold front stretches back into Minnesota and
the Dakotas. Another round of thicker cloud cover and light precip
is sliding southeastward through the Upper Midwest along the
front/tight thermal gradient with some light RA/SN being reported.

Primary Forecast Concerns: Minor. Increasing lake effect snows
late tonight into Sunday.

Surface low over Lake Superior further departs into Canada,
gradually nudging the cold front back down into northern Michigan
later tonight. Round of upstream light precip will eventually
spread across the region later this evening and overnight. But
similar to last night, I don`t expect much...some light snow or
flurries with minor accumulations.

However, winds veer northwesterly with colder air spreading back
into the region. This will push lake effect precip back through
eastern Upper Michigan and eventually back into parts of northern
Lower Michigan as we go through the night. Heavier of the lake
effect snow showers will impact parts of northern Chippewa
county, especially around Whitefish Point, where a couple of
inches of snow are possible overnight. Lesser amounts in the
snowbelts of northern Lower Michigan, maybe an inch. No headlines
planned at this juncture.

&&

.SHORT TERM...(Sunday through Tuesday)
Issued at 337 PM EST Sat Nov 9 2019

...More Lake Lake Effect...

High Impact Weather Potential...There could be moderate to heavy
lake effect Sunday night as the winds veer north overnight into
Monday morning. Temperatures remain cold enough to keep the lake
effect at least moderate depending on the consistency of the wind
directions.

Pattern Synopsis/Forecast...As today`s clipper moves into Quebec,
the cold air behind it pushes into the Upper Great Lakes, and drops
our 850 mb temperatures to around -8c by 12z/Sun. High pressure
continues to build int the region, through the day, which veers the
winds from NW to NNW to N by 00z/Mon. 850 mb temperatures by 00z/Mon
are -17c in E Upper and -15c over N Lake Michigan. The models have
most of the snow bands roughly west of US-131 Sunday night into
Monday morning with the SREF showing some spread to put snow into
areas near I-75. Also, the models begin to have different degrees of
NNE winds over Lake Huron so that portions of NE Lower may see some
LES Sunday night as well. Monday, the winds begin to back to the NW
which looks to move the snow bands into the NW and NC Lower with the
more favored NW flow regions. This flow regime looks to last through
Tuesday afternoon before the 1000-850 mb layer wind ridge axis
pushes into the region by the evening, as well as the 850-700 mb
layer dry air.

Primary Forecast Concerns...Most of this forecast is dominated by
the cold air that is pushing into the region from the Arctic high
that has been progged over the last couple of days. So the main
concern will be the wind direction. While temperatures are expected
to fall, and put us into a favorable LES pattern that could support
some really good instability, the main concern then comes down to
the wind direction and how long the wind remains from a particular
direction, and thus how long will the snow be falling in one place.
Also a concern, when the winds veer or back, if the change in
direction is significant enough, then band mergers are possible, and
very heavy snow is possible in a smaller time period. All of the
models point at these being an issue, especially the SREF as the
mean snow fall amounts are spread out quite a bit, with fewer bull`s
eyes down the streamlines. That seems to mean that the snow is more
spread out, than any of the deterministic models.

.LONG TERM...(Tuesday night through Saturday)
Issued at 337 PM EST Sat Nov 9 2019

High Impact Weather Potential...The rest of the week looks to be LES
dominated as the cold temperatures (<-10c 850 mb) continue.

Extended (Tuesday evening through Saturday)...Tuesday evening, the
ridge axis moves through the region, and turns the winds from NW to
S. This would produce some snow in NW lower, but probably closer to
MBL and FKS, otherwise the band that would form would impact ISQ to
about Naubinway overnight and into Wednesday evening. Wednesday
evening, the trough moves through the region and the winds veer NW,
and we continue the chance for snow showers through Thursday.
Thursday night, the winds begin to back again to the west, and the
850 mb temperatures warm to around 0C. So the precipitation will
come to an end by Thursday evening. The models show another cold
front on Friday, but all of them are bringing it through dry. With
the 850 mb temperatures falling upstream, not sure that I buy it.
However, will leave the forecast as is. The reason I`m not sure
about it is the -15C temperatures over Lakes Superior and Michigan.
Think that with the instability there will be some snow, but the air
is very dry, so it may be flurries if there are any.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 628 PM EST Sat Nov 9 2019

IFR cigs PLN late tonight.

Low pressure ne of upper MI will continue to move away from the
region. However, this system will drag a cold front across
northern MI tonight and early Sunday. MVFR cigs are already
prevalent across eastern upper and far northern lower MI. These
will expand southward today and lower a little further. Expect IFR
cigs for a period at PLN late tonight. Otherwise, a mix of MVFR to
VFr conditions is forecast. Patchy light snow will also expand
back into the region as cooler air returns.

Present ssw winds will become nw early Sunday and north later in
the day.


&&

.MARINE...
Issued at 337 PM EST Sat Nov 9 2019

Gustier SW winds diminish this evening. Will keep small craft
advisories going on Lake Michigan through the evening as waves
diminish back below small craft criteria. Gustier NW winds develop
late tonight through Sunday night...and a fresh round of small
craft advisory headlines will likely be needed at that time.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...SMALL CRAFT ADVISORY until 11 PM EST this evening for LMZ342-
     344>346.
LS...NONE.
&&

$$

UPDATE...JZ
NEAR TERM...BA
SHORT TERM...JL
LONG TERM...JL
AVIATION...JZ
MARINE...BA



Area Forecast Discussion

National Weather Service Charleston SC

 1020 PM EST Sat Nov 9 2019

.SYNOPSIS...
High pressure will linger into early next week. A cold front
will pass through the area Tuesday, before high pressure
returns and prevails through Thursday. A low pressure system
could the impact the region next weekend.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
The biggest concern for tonight is in regards to how cold temps
get and how much frost there will be. Almost ideal radiational
cooling will continue away from the coastline, and we expect
lows most places inland to drop colder than they were Saturday
morning. There is definitely a potential for us being too cold
as the HREF, HRRR, SREF and RAP all continue to show min temps
a bit above freezing. But since much of this guidance
initialized to "warm" and some of the MOS guidance still
suggests min temps of 31-32F, we have maintained the Freeze
Warning as before. No changes to the Frost Advisory, with
scattered to widespread coverage.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
Sunday and Monday: The center of sfc high pressure will remain
across the forecast area on Sunday, sliding NE along the Atlantic
coast Sunday night into Monday. Sunny conditions and light winds
will remain across the CWA, resulting in temperatures to warm around
30 degrees between sunrise and mid-afternoon. High temperatures are
forecast to generally range in the mid to upper 60s. As the high
center shifts north, light return flow should develop across the
region late Sunday night into Monday. As a result, milder
thicknesses will limit cooling Sunday night, but values are expect
to fall 3 to 6 degrees below normal. Using a blend of MOS, I will
forecast low 40s inland to the mid to upper 40s across the coastal
counties. A cold front is forecast to run from the Arklatex NE across
the Ohio River Valley by sunset Monday. LLVL return flow is expected
to gradually increase through the day. High temperatures on Monday
should peak around seasonable normals, ranging in the low to mid 70s.

The cold front is forecast to slide across the southern Appalachians
Monday night. Mid and high clouds ahead of the cold front will
spread across the CWA, yielding at least BKN sky conditions by
Tuesday morning. Low temperatures are expected to remain around 10
degrees warmer than Monday morning values. Short range guidance
times a band of showers associated with the cold front sweeping west
to east across the CWA during the daylight hours Tuesday. I will
forecast low likely PoPs on Tuesday, QPF should favor values around
a quarter of an inch. High temps expected to range in the mid to
upper 60s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Dry/cool high pressure will build across the area behind a departing
cold front Tuesday night, then will persist through at least early
Thursday. The main issue will be cold overnight temps Tuesday night
and Wednesday night. Latest guidance suggests cold air advection
followed by radiational cooling helping temps lower into the upper
20s inland to lower/middle 30s near the coast Tuesday night. A Frost
Advisory or Freeze Watch/Warning could eventually be needed for most
areas away from the coast. Conditions will remain dry and struggle
to warm during the day on Wednesday with afternoon highs only
peaking in the upper 40s to lower 50s. Wednesday night will see
conditions similar to the previous night as a light north/northeast
wind prevails along the southern edge of high pressure centered to
the north. However, low temps should be a degree or two warmer,
ranging in the low/mid 30s inland to upper 30s/lower 40s near the
coast.

Temps should slowly warm back into the mid/upper 50s Thursday while
a coastal trough develops along the Southeast coast. Isolated to
scattered showers are possible, especially later in the day as the
coastal trough enhances ahead of a potentially strong low pressure
system developing over the Gulf of Mexico. The low pressure system
could track across the Southeast United States and/or just offshore
Thursday night through Saturday, producing scattered to perhaps
numerous showers during the weekend, some of which could be heavy
rainfall producers given PWATs approaching 1.5-1.75 inches across
southern areas.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
VFR at KCHS and KSAV through 00Z Monday.

Extended Aviation Outlook: VFR conditions will prevail through
Monday night at both CHS and SAV terminals. Ceiling and/or low
vsbys restrictions are possible Tuesday morning into Tuesday
night due to showers along and ahead of a passing cold front.
VFR conditions expected at both CHS and SAV terminals Wednesday
and Thursday.

&&

.MARINE...
Tonight: Winds and seas will continue to slowly decline through
the night as high pressure builds over the Southeast United
States. We still have a Small Craft Advisory for lingering 6 foot
seas on the outer GA waters, with seas no more than 3 or 4 feet
elsewhere. Winds on average will be north at 10-15 kt.

High pressure will remain across the coastal waters Sunday
through Monday night. The pattern should yields winds 10 kts or
less with seas of 1 to 3 ft. A cold front will sweep across the
region on Tuesday, gusty NW winds are expected during the late
afternoon and evening hours. Short term guidance indicates that
winds will strengthen to near gale force with the arrival of CAA
Tuesday night. Gale Watch/Warning Tuesday night into Wednesday
morning. Small Craft Advisory conditions may linger across
waters on Wednesday, the outer GA waters through Wednesday
night.

&&

.TIDES/COASTAL FLOODING...
Tide levels in the Charleston Harbor will be close to the
requirement of a Coastal Flood Advisory early Sunday morning.
Our latest thinking is for around 7.0 to 7.1 ft MLLW. Tide
levels will not be high enough at Ft. Pulaski for an advisory.

Levels will remain elevated through at least the middle of the
week, and Coastal Flood Advisories could be required for the
morning high tides.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Freeze Warning until 8 AM EST Sunday for GAZ087-088-099>101.
     Frost Advisory until 8 AM EST Sunday for GAZ114>116-137-138.
SC...Freeze Warning until 8 AM EST Sunday for SCZ040-042>045-047.
MARINE...Small Craft Advisory until 5 AM EST Sunday for AMZ374.

&&

$$
NEAR TERM...
SHORT TERM...NED
LONG TERM...DPB
AVIATION...
MARINE...
TIDES/COASTAL FLOODING...




Area Forecast Discussion

National Weather Service Cheyenne WY

 443 PM MST Sat Nov 9 2019

.UPDATE...
Issued at 432 PM MST Sat Nov 9 2019

Afternoon update to the forecast included the cancellation of the
Red Flag Warning for Fire Weather Zone 313 in the Nebraska
Panhandle. Several daytime maximum high temperatures were tied or
broken in regard to temperature records. A more detailed report
will likely be available on social media and the website within
the next 12-24 hours.


&&

.SHORT TERM...(Rest of this afternoon through Monday night)
Issued at 200 PM MST Sat Nov 9 2019

The early afternoon WV/IR loop revealed a upper ridge over the
southwestern US, with a west-northwest flow aloft prevailing.
Warming/drying downslope winds lee of the Front Range and mostly
sunny skies resulted in near record or record high temperatures.
Cheyenne WY tied its record high of 70 in 2016, and may exceed
the record by late afternoon. Scottsbluff and Sidney NE already
broke their respective record high temperatures. Strong westerly
winds continued across portions of the wind-prone areas of
southeast WY. Bordeaux (zone 106) measured a peak gust of 58 mph
and Arlington (zone 110) 57 mph. Peak gusts of 50 to 55 mph were
observed near the I-80 Summit. Winds the past hour were slowly
diminishing, as are the 700/850mb gradients and winds aloft. High
Wind Warnings may be cancelled by 3 PM. Expect partly cloudy skies
and seasonably chilly temperatures tonight.

Attention turns to the arrival of the arctic front which currently
extends from northern MT and ND into central MN. There are minor
timing differences, with the GFS a bit faster than the ECMWF.
Front enters east-central WY and the northern NE Panhandle early
Sunday afternoon, and southeast WY and southern NE Panhandle late
Sunday afternoon. Temperatures will reach the low to mid 50s
ahead of the front Sunday afternoon, and fall through the 30s and
40s behind it. Rain will transition to a wintry mix of snow and
freezing drizzle Sunday evening, then become all snow per model
sounding profiles. Modest dendritic growth will result in light
snow accumulations, mainly one to two inches east of the Laramie
Range. Ice accretion will be minimal. Travel impacts will be
limited to snow-covered, slick road surfaces. Visibility
restrictions will be minimal due to light snow and lack of
blowing snow.

Snow tapers off from north to south Monday morning. It will be
much colder compared to today/s highs with 700mb temperatures in
the -10 to -16C range. The arctic front stalled just west of
the Front Range shifts east Monday night. CAG-CPR and CAG-BRX
700/850mb gradients increase to 55 to 65 meters by 12Z Tuesday
as well as GFS 700mb winds near 45 kt. High wind headlines may
be required for Arlington late Monday night.

.LONG TERM...(Tuesday through Saturday)
Issued at 150 PM MST Sat Nov 9 2019

Cold air quickly departs the CWA Tuesday as the surface high sinks
into the southern plains with temps rebounding nicely. It will
also be windy at times across southeast Wyoming. Next shortwave
clips the area Weds but latest model runs backing off on effects
with little or no QPF and just a minor cool front. Will keep low
pops in place for now to see if this stays consistent. Upper
ridging Thursday and Friday keeps mild and dry weather over the
area. Next shortwave approaches the CWA Saturday and could spread
some pcpn into the CWA by late in the day.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 406 PM MST Sat Nov 9 2019

Changes coming in the TAFs as a backdoor cold front moves into the
area from the northeast after 06Z. Northeast winds behind the
front will create low clouds and some fog over the northern
Nebraska Panhandle airports...possibly as far southwest as KTOR
and KBFF. Used HRRR timing on onset of low clouds. Next surge with
front moves in Sunday afternoon with snow developing after 00Z
Monday.


&&

.FIRE WEATHER...
Issued at 111 PM MST Sat Nov 9 2019

Minimum relative humidities from 10 to 15 percent combined with
gusty west to northwest winds up to 30 mph and prime fuels will
create critical fire weather conditions this afternoon. A Red Flag
Warning remains in effect until 6 PM MST for the southern Nebraska
Panhandle. A surge of colder air arrives Sunday afternoon and
evening, along with occasional light snow and freezing drizzle.
The mixed precipitation will end by Monday afternoon. Breezy and
milder weather is forecast Tuesday and Wednesday.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&

$$

UPDATE...BW
SHORT TERM...MAJ
LONG TERM...RE
AVIATION...GCC
FIRE WEATHER...MAJ