Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/03/22
Area Forecast Discussion
National Weather Service Burlington VT
931 PM EST Fri Dec 2 2022
Strong winds are expected on Saturday, especially across
northern New York, along and behind a cold front which shifts
east during the afternoon. Bouts of rain are expected as this
weather system approaches and then departs late in the day, with
lingering snow showers on Sunday before trending mainly dry on
Monday. The next weather system arrives towards next Tuesday
.NEAR TERM /THROUGH SATURDAY NIGHT/...
As of 931 PM EST Friday...Focus of this update was adding
chance of precipitation associated with a large area of
elevated showers racing eastward into northern New York at this
time. There has been enough reflectivity returns off the TYX
radar (> 35 dbZ) to assume some rain will reach the ground
despite the very dry low level air below the rain producing
clouds. 00Z HRRR reflectivity initialized this line of showers
well and have incorporated its output into the precipitation
forecast through the next 6 hours as it moves eastward through
our region. Marginally cold low level temperatures and wet bulb
temperatures in the column below the cloud layer will likely
yield a variety of precipitation types as the showers reach
central and eastern sections of Vermont overnight. Fortunately,
amounts will be light enough to likely limit impacts of any
frozen precipitation with trace amounts of ice currently
forecast, but it bears watching.
Previous Discussion... Tonight will feature mostly dry weather
but strong gusty southerly winds. Winds will be increasing as
pressure gradient tightens between high pressure just off to our
east and low pressure system over the Great Lakes which will be
lifting north of our region on Saturday. Minimum temperatures
will be mild, dipping into the mid 20s to mid 30s, warmest in
the Champlain and St Lawrence valleys. A warm front will lift
across our area overnight, and will likely see some virga
associated with this first frontal passage, but certainly an
increase in clouds. Towards early Saturday morning rain will
start to spread west to east into our region, and some colder
pockets in the Adirondacks could have some freezing rain early
in the morning. Rapid warming will change all precipitation to
rain by mid morning Saturday as the rain continues to spread
across the rest of the area from west to east ahead of a surface
cold front. Will also have a surge in strong winds Saturday
morning. Winds will be out of the west southwest and will have
some downsloping effects north of the Adirondacks. Areas across
the northern tier of NY will experience the strongest gusts,
especially Malone, Chateaugay, Ellenburg, Chazy areas. Meanwhile
strong southerly winds continue in the Champlain valley over
and along the lake, especially Grand Isle county and in western
Franklin county. Isolated wind gusts will be as high as 50 mph.
See wind advisory for further details. High temperatures on
Saturday will reach the mid 40s to lower 50s. Winds will start
to let up as we head into the evening hours and cold front
pushes east of our region. Cold air behind the departing cold
front will change rain over to snow showers, especially in the
higher elevations. As the flow becomes northwesterly behind the
departing cold front, we`ll also see some lake effect snow
showers from Lake Huron reaching our area on Saturday night. Low
temperatures on Saturday night will dip into the 20s areawide.
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
As of 242 PM EST Friday...A quiet period of wx anticipated with
mid/upper lvl troughiness, while 1020mb sfc ridge builds into
our cwa. The cyclonic nw flow aloft and moderate llvl caa
supports lingering light mountain snow showers on Sunday
morning, but depth of moisture is very limited. Good news
thermal profiles wl support snowmaking operations at all
elevations at local resorts with 925mb temps in the -8C to -10C
at 12z Sunday, while 850mb temps are in the -13C to -14C range.
Have adjusted summit temps back into the teens for highs on
Sunday while valleys warm into the upper 20s to mid 30s. By
Sunday evening parameters become slightly more favorable for
minor lake effect snow showers to impact southern SLV, mainly
south of Route 3. Cloud layer flow shifts to a southwest
direction, while marginally cold air is available to produce
some lake enhanced snow showers. Any accumulations wl be light
and generally under an inch. Lows range from the mid teens to
mid 20s, but should warm aft 06z as southerly flow develops
ahead of our next system. Coldest valley wl be acrs eastern VT,
including the NEK.
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 242 PM EST Friday...Mid/upper lvl pattern wl feature a
fast west to east zonal flow acrs the conus, separating warmer
air to the south and cooler air acrs the northern tier. A series
of weak and poorly defined boundaries wl cross our fa on Tues
thru Thurs, resulting in an unsettled wx pattern. First wave
approaches cwa late Monday night into Tues, with strong
south/southwest 850mb winds of 40 to 50 knots, advecting in
warmer thermal profiles. Best 5h forcing along with narrow
ribbon of enhanced 850 to 500mb rh profiles moves from west to
east acrs our cwa on Tues. Strong southwest downslope flow wl
result in shadowing acrs the CPV on Tues, with a high pops and
light to locally moderate qpf event anticipated (0.10 to 0.35).
Given warming thermal profiles and initial sfc low pres tracking
to our west, expecting mostly rain again acrs our fa, but some
colder valleys could see a brief period of light mix on Tues
morning, as colder/denser air remains trapped. Any ice
accumulation wl be light. As fast confluent flow aloft prevails
for mid week, boundary becomes hung up acrs the Ohio Valley/NE
CONUS into New England. Uncertainty develops in the placement of
best moisture and forcing, along with thermal profiles, but
with boundary nearby an unsettled period of wx is possible for
mid week. For now have continued with chc pops and wl wait for
better agreement in guidance before increasing pops to
likely/cat. Unfortunately we remain on the warmer side with
southerly flow thru midweek, so most of the precip wl probably
be in the form of liquid, until some cooler air at 850mb arrives
late Weds into Thurs. Cooler 925mb to 850mb thermal profiles
gradually advect into the fa on Thurs into Friday, as 1036mb
high pres near Hudson Bay noses into our region. A brief period
of upslope snow showers are possible during the modest caa
pattern, but available moisture on the progged wind component is
limited. In the temp department, expect above normal values for
Monday thru Weds, before trending toward normal for Thurs into
Friday, while lows are mainly in the 30s but trend into the 20s
by late week. A period of breezy winds are possible on Monday
night into Tues, as gradient btwn departing 1032mb high pres and
approaching 1003mb low pres tightens, along with 850mb jet of
40 to 50 knots. Localized gusts 35 to 45 mph possible in the CPV
and northern dacks.
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Through 00Z Sunday...Mainly VFR conditions are expected through
12Z. South winds 8 to 15 knots, with gusts of 16 to 25 knots,
will continue to increase gradually at BTV, PBG, and RUT.
Areawide, south or southwest LLWS will also increase and peak
around 12Z, greatest at SLK with 65 knot shear up to 2000 feet.
After 12Z, 20 to 30 knot gusts will start to develop at all
sites, with strongest winds remaining at BTV gusts greater than
30 knots are expected. LLWS should abate after 18Z.
Two periods of rain showers are expected. The first area of
showers will help moisten the air and lower ceilings to MVFR in
most locations by 16Z. Then a more organized area of showers
along a cold front is expected, passing through MSS soon after
18Z, Champlain Valley around 20Z-21Z, and eastern Vermont around
22Z. Winds will shift sharply from southerly (or southwesterly
at MSS) to westerly with a few strong gusts in its wake, mainly
in the 20 to 30 knot range at Vermont sites and 35 to 40 knots
at New York sites. Ceilings should trend back up to VFR briefly
before MVFR ceilings likely redevelop, especially at SLK towards
Saturday Night: Mainly VFR, with local MVFR possible. Windy with
gusts to 30 kt. Slight chance SHRA, Slight chance SHSN.
Sunday: VFR. Slight chance SHSN.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. Slight chance SHRA, Slight chance SHSN.
Tuesday: Mainly MVFR, with local VFR possible. Likely SHRA.
Tuesday Night: Mainly MVFR, with local IFR possible. Chance SHRA.
Wednesday: Mainly MVFR, with areas IFR possible. Chance SHRA.
Strong south winds of 20 to 35 knots with gusts up to 50 knots
will continue until a cold front passes through Saturday
evening. Strongest winds will be in the morning hours and over
the broad lake and Inland Sea. As winds turn westerly during the
evening, wind speeds will gradually diminish into the 15 to 20
knot range. Wave heights will build to 3 to 5 feet with an area
of 5 to 7 feet over the broad lake, greatest near Colchester
Reef, diminishing during the afternoon.
The KCXX radar will be down for around 2 weeks (through
approximately December 12) for a scheduled pedestal replacement
on site. This a critical repair to ensure the operational
longevity of the equipment.
VT...Wind Advisory from 5 AM to 6 PM EST Saturday for VTZ001-002.
NY...Wind Advisory from 5 AM to 6 PM EST Saturday for NYZ026>031-
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
537 PM CST Fri Dec 2 2022
.DISCUSSION...(This evening through Friday)
Issued at 316 PM CST Fri Dec 2 2022
* Near-critical to critical fire weather conditions remain a
concern across southern portions of the CWA over the next couple
hours, so will keep the Red Flag Warning as is through 6 PM.
* Though the area of highest wind gusts the rest of this
afternoon/evening looks to be primarily focused across western
portions of KS, the threat for isolated gusts near 60 MPH
remains, so will also keep the High Winds Warning as is through
10 MPH. There is a chance this may be cancelled early.
* The majority of this 7-day forecast is dry. Precipitation
chances are lower-confidence at this point, and are in the
Monday night and Wed night-Thursday time frames.
Though dry across the region, it certainly hasn`t been a quiet and
calm day, as a strong surface cold front continues to push south. In
the mid-upper levels, satellite and upper air data show a trough
axis continuing to push east through the Nrn/Central Plains, the
main driver of this sfc front. As models had shown the past couple
days, pressure rises have been hefty behind the front, a trend that
will continue south-southeastward through the rest of the day. Here
at mid-afternoon, the stronger gusts are working their way into the
northern/western fringes of the CWA, with higher gusts currently
focused just off to our west. Skies have gradually cleared through
the day, making it easy to pick out the impressive wall of dust that
developed around midday along the sfc front, and has intensified as
it treks SSE through western KS. HRRR has been handling things fairly
well today, and continues to focus the worst of both the wind/dust
just off to our WSW through the rest of this afternoon. If anything,
the front moved in just a touch faster than forecast, and while some
timing adjustments were made with time to wind, temps,
dewpoints...overall there hasn`t been any surprises. Will be keeping
a close eye on how that main area of dust trends over the next
couple hours and its potential impact on our western areas to see if
any type of shorter-fused dust headline may be needed.
As far as the headlines go, will keep things as is at this point.
For the Red Flag Warning across our south, sub-20% RH values are
solidly in place, winds are switching and remain gusty...once the
colder air builds in the RH values will climb, but the warning only
runs until 6PM so am fine letting it ride for now. The High Wind
Warning for areas along/south of Interstate 80 runs through 10 PM.
Compared to 24hrs ago and even last night`s mid shift runs, models
today have trended back a touch on the highest gust potential for
our CWA...as mentioned above, keeping the worst of it just off to
our WSW. However, especially for roughly the west-southwest third or
so of the CWA, certainly not ruling out at least isolated gusts near
60 MPH through this evening...so will keep the warning going as is
Mid-evening through the overnight hours tonight, winds will taper
off. Models remain in good agreement showing sfc high pressure
continue to sink southeast out of the Nrn Rockies, settling over the
heart of the Central Plains by sunrise Saturday. Could have some
gusty conditions linger through late evening/midnight across far ESE
areas, but after midnight speeds to diminish to closer to 5-10 MPH.
With skies expected to remain mostly clear and a cooler air mass
accompanying that sfc high, overnight lows tonight are forecast to
fall into the single digits above zero in NWrn portions of the area,
with low-mid teens across the SSE.
In the wake of this mid-upper level trough axis sliding east today,
models continues to show zonal flow setting up across the region,
with an overall lack of any notable disturbances to bring us
precipitation chances. At the surface, we`ll see a fairly quick
return of southerly winds during the daytime hours tomorrow as the
main area of high pressure slides east...and there will be the
potential for gusty winds during the afternoon for areas along/west
of HWY 183. Not looking at anything like today, but gusts near 20-25
MPH will be possible. The cooler airmass looks to keep highs for
Saturday in the mid 30s east to low 40s west...and while skies are
mostly clear to start the day, increasing upper level clouds are
expected during the afternoon. Lighter winds are expected for
Sunday, with a bump up in highs into the mid 40s to near 50.
Next week - Monday through Friday...
With the busier ongoing short-term, didn`t spend a lot of time
fretting over the details of the longer term forecast. For the most
part, dry conditions are expected, with two main chances for any
preciptiation. The first chance comes Monday night with the arrival
of a low-amplitude shortwave embedded in the continued zonal flow.
However, overall confidence is low...as models/NBM have gone back
and forth with whether or not our CWA sees anything, if we do -
when, etc. PoPs are low, and chances look like they`d mainly affect
portions of south central NE with some light snow. The other chances
are focused in the Wed night-Thurs time frame...but similar to
Monday, confidence is low.
As far as temperatures go, currently not looking at any significant
swings either way in temperatures...with highs generally in the
30s/40s and lows in the teens/20s.
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday)
Issued at 530 PM CST Fri Dec 2 2022
VFR conditions persist through the forecast period at KGRI and
KEAR terminals. Gusty northwest winds continue as a strong cold front
continues its push to the southeast this evening. Winds are
expected to continue to decrease over the next few hours at the
surface, however, there continues to be a concern of some LLWS
around 05-09Z as winds aloft remain strong. Winds will continue to
decrease through around sunrise where they transition from
northwest to southwest.
NE...Red Flag Warning until 6 PM CST this evening for NEZ082>087.
High Wind Warning until 10 PM CST this evening for NEZ060>064-
KS...Red Flag Warning until 6 PM CST this evening for KSZ005>007-
High Wind Warning until 10 PM CST this evening for KSZ005>007-
Area Forecast Discussion
National Weather Service Memphis TN
856 PM CST Fri Dec 2 2022
Issued at 824 PM CST Fri Dec 2 2022
00Z upper air analysis indicates broad nearly zonal to slightly
southwest flow aloft across the Southern Plains and Lower
Mississippi Valley with a mid-level shortwave trough located over
the Northern Plains and Rockies and a subtle shortwave trough
over the Lower Mississippi Valley this evening. Meanwhile, at the
surface a cold front stretches from Western Lake Superior back
through Western Missouri and into Kansas and Texas. Lift produced
by the shortwave and increasing low/mid level moisture has
resulted in the development of additional showers across the Mid-
South. As of 8 PM CST, temperatures across the forecast area are
in the 50s to lower 60s.
Short term models including Convective Allowing Model solutions
(CAMs) indicate the potential for showers will increase overnight
into Saturday morning. A few thunderstorms may be also be possible
as some weak elevated instability will be present. Will make some
adjustments to rain chances to account for short term trends.
Otherwise, forecast overall in good shape.
Updated grids will be available shortly.
(This evening through next Thursday)
Issued at 240 PM CST Fri Dec 2 2022
Showers and thunderstorms will move through the area tonight and
persist through Saturday morning. Then a short lull will occur
Sunday into Monday. More showers will push into the area Monday
night through Wednesday near a stalled boundary. Up to 2 to 4
inches of rainfall are possible.
Currently, warm air advection showers can be seen on radar as a
front begins to approach the area. The aforementioned front will
begin to move into eastern Arkansas tonight and continue
throughout the night. The front will make its way into Memphis
around 6 AM with temperatures quickly dropping behind it. Ahead of
the front expect temperatures in the 60s, then there will be a
quick drop to the 50s and 40s. Wind gusts could be up to 35 mph
before the front moves through and after. Rain will diminish as
the front exits the region by tomorrow afternoon.
High pressure will move into the area Saturday night but will
swiftly push eastward. After the front pushes through, Saturday
should be a nice day, but chilly. Temperatures will be in the 60s.
Lows Saturday night will be in the 30s. Temperatures Sunday will
generally be in the 40s with low temperatures in the upper 30s.
By Monday the subtropical jet will be in full swing as a warm
front begins to slowly lift northward. Upper level flow will be
oriented parallel to the boundary. Thus, expect showers to
continue to affect the region. Furthermore, with the potential
for cell training, some instability will be in play and could add
to rainfall totals. The warm front will finally move eastward and
showers should end by Thursday. We could see up to to 2 to 4 inches
of rainfall over the next 7 days. We could see even more rainfall
depending on location of the front. Will continue to monitor.
Issued at 555 PM CST Fri Dec 2 2022
Low level wind shear and prefrontal CIG transition timing to high
IFR/low MVFR remain the main story for the evening. NAM FL020
winds depicted at 60 to 65KT around JBR by 03Z. MEM will remain
near the tail of this southwesterly low level jet during the
arrival push. May need a bump to 23060KT for FL020 winds at MEM,
if the NAM`s characteristic conservatism comes into play.
Overnight TS chances minimal, and considered removing VCTS.
Otherwise, IFR CIG chances increase toward the end of the MEM
Latest HRRR guidance suggests the surface cold front has sped up
slightly. Surface winds will be the main concern Saturday, with a
secondary concern of VFR timing at TUP. Followed a GFS LAMP/NBM
blend for TUP sky conditions trends on Saturday.
Area Forecast Discussion
National Weather Service Morristown TN
1026 PM EST Fri Dec 2 2022
Issued at 1018 PM EST Fri Dec 2 2022
Light showers have started falling across parts of the area.
Updated the forecast to account for this, as original thinking
was it might take a bit longer for moisture to reach the surface
due to the dry air that was in place. Nudged temperatures a bit
to a warmer guidance overnight due to the cloud cover and rain
that may keep temperatures a bit more mild overnight. As a result,
RH`s overnight will be increasing as well.
(This evening through Saturday)
Issued at 315 PM EST Fri Dec 2 2022
1. Chances of rain increase tonight through tomorrow morning as a
cold front approaches and moves through the area.
2. Strong southwesterly flow at 850mb tonight into tomorrow morning
will produce gusty winds for the higher elevations of the East TN
mountains, southwest VA, and the northern Cumberland Plateau.
Tonight and Tomorrow
Dewpoints are still on the low side this afternoon as reflected in
both area observations and soundings. This dry air in the low to mid
levels will moisten through time as southwest flow increases ahead of
the cold front. The HRRR and RAP both show measurable precip not
moving in until after midnight, though a few sprinkles are certainly
possible before then. From midnight onward, precip chances ramp up
from slight chance to categorical POPs by Saturday morning. We begin
to dry out Saturday afternoon as the front passes through but precip
chances will linger across the far eastern TN mountains through the
remainder of the day. Total precip will average around 0.25 inches
for most places. Lastly, soundings still showing very little
instability so while mainly rain is expected don`t be surprised if
there is a rumble of thunder or two.
850mb flow increases this evening ahead of the cold front and peaks
at 40 to 50 kts between 06Z and 12Z. The current wind advisory
across the east TN mountains goes into effect tonight at 7 PM EST
and expires at 7 AM Saturday morning. However, based on latest model
guidance, will extend the advisory until 15Z. Wind gusts from 40 to
50 mph are expected within the advisory area. Other areas such as
the mountains of southwest VA and the northern Cumberland
Plateau can expect to see gusts from 30 to 40 mph.
(Saturday night through next Friday)
Issued at 315 PM EST Fri Dec 2 2022
1. Dry weather to start the period with near normal temperatures.
2. Wet pattern sets up Monday and continues through Thursday.
Possibility of flooding if a location gets several days of moderate
to heavy rainfall.
Behind the front cooler and drier weather is expected for Sunday and
into the first part of the work week, as surface high pressure sets
up along with quasi-zonal flow through the mid levels of the
atmosphere. Temperatures on Sunday will be about 10 degrees colder
than Saturday, but they won`t remain that cold for very long as a
quick warmup is expected early next week.
Along with the warmer temperatures, we move into what should be a
much wetter pattern through most of the upcoming work week, as
multiple synoptic systems look to impact the region. First system
looks to be a shortwave moving through the southern stream across
the Tennessee Valley ahead of an approaching front. Models are
coming into better agreement on the onset timing of this system,
which should move into eastern Tennessee Monday evening. The peak
intensity of this rain is expected to be Monday night into Tuesday
morning, along with the strongest surge of Gulf moisture. Forecast
soundings continue to show over 1" of PWAT in the atmosphere south
of Interstate 40, with lower amounts to the north. This is above the
90th percentile based on climatological sounding data. So there
could be periods of moderate to heavy rainfall overnight, and if a
urban or poor drainage locations see`s multiple rounds of moderate
to heavy rain, there could be some localized flooding.
However there will likely be a higher flooding threat during the
middle and second half of the week, as more rain continues to fall
across the Ohio and Tennessee Valleys. The frontal boundary behind
this initial round of rain is forecasted to stall out somewhere
across the Ohio or Tennessee Valley. The location of this boundary
will be the key factor in determining what locations get the
heaviest, and repeated, rounds of rain... Unfortunately at this time
there is still disagreement in the long range models of where this
boundary will set up. If it sets up across the Tennessee Valley,
then our area would likely see repeated rounds of rain Tuesday
through the end of the week. If the boundary stalls out further to
the north and west (across the Ohio Valley) then we`d likely still
see rain, but more dry periods in-between. Long story short, it
looks like there will definitely be moderate to heavy rain moving
across the Ohio or Tennessee Valleys through much of next week, but
there is still uncertainty on exactly WHERE this heavy rain will
occur. Current QPF amounts are showing the possibility of 3+ inches
in some parts of the eastern Tennessee Valley for the entire work
week... however these amounts can (and likely will) change as the
models wrestle with where the frontal boundary will stall out and
slowly meander around. Will continue to highlight the threat of
isolated flooding in the HWO. Temperatures next week should be back
above normal, and with the cloudy skies, overnight lows also stay
above normal... Warm enough that any precipitation next week should
be all liquid across the entire region.
Issued at 637 PM EST Fri Dec 2 2022
At least the first 6 hours of the TAF period expected to be VFR at
all 3 terminals. After 06Z, CHA and TRI possible LLWS within the
vicinity, so this is reflected in the TAF. Closer to morning, LLWS
threat subsides, CIGs lower and the chance of rain increases as a
front approaches from the west. MVFR CIG and VSBY with occasional
IFR conditions at times. Winds could gust out of the southwest around
15kts within the passing of the front. Conditions expected to
improve behind the front towards the end of the TAF period.
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 50 64 37 52 / 70 80 0 10
Knoxville McGhee Tyson Airport, TN 50 62 35 50 / 70 80 0 10
Oak Ridge, TN 49 61 33 50 / 80 80 0 10
Tri Cities Airport, TN 46 58 32 49 / 70 80 10 0
TN...Wind Advisory until 10 AM EST Saturday for Blount Smoky
Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky
Mountains-Southeast Carter-Southeast Greene-Southeast