Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/24/22
Area Forecast Discussion
National Weather Service Goodland KS
803 PM MST Wed Feb 23 2022
.UPDATE...
Issued at 756 PM MST Wed Feb 23 2022
Model data this shift continues to indicate the potential for a
narrow band of snow to form over the northwest part of the
forecast area overnight into Thursday morning. Frontogenesis,
convective lapse rates, and isentropic lift over the northwest
part of the forecast area during this timeframe are favorable for
this band of higher snow amounts forming. The last 5 or so runs of
the HRRR have been highlighting this part of the forecast area for
higher snow amounts, but differ in the location of the band. The
last two runs of the HREF, and several runs of the RAP also favor
a band forming over the northwest part of the forecast area
tonight. Snow probability of the 25th percentile shows almost
three inches north of Wray, which adds confidence that advisory
level snow will occur under the band of snow.
Due to model variability with the placement of the band,
confidence is not high enough issue an advisory at this time. Will
highlight the potential for these higher snow amounts with other
products in the meantime.
These snow amounts will add to the hazardous conditions of the
cold wind chills tonight.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 235 PM MST Wed Feb 23 2022
A Wind Chill Advisory has been issued for a portion of the area
along and west of the eastern Colorado border region between 8pm
MST tonight and 8am MST Thursday morning.
The primary concern in the short term is the possibility of
Advisory level Wind Chill values Wednesday night into Thursday
morning.
Overnight low temperatures in the single digits above and below
zero will combine with mainly light east to southeast winds
overnight and early Thursday morning to produce wind chill values
as low as 15 to 20 degrees below zero. Along with the cold wind
chills, light snow is expected to develop after midnight as the
upper trough currently moving through the Intermountain West
moves east of the Central Rockies tonight and across the central
High Plains Thursday morning. The best lift associated with the
upper trough occurs between midnight tonight and mid-day on
Thursday, and will correspond to the highest snowfall
accumulations across the area. Snowfall amounts will generally be
light with a range of one half inch to 2 inches across the
forecast area. The greatest accumulations are expected across
southwest Nebraska and along the northern Kansas border area. Snow
tapers off Thursday afternoon as the upper trough moves east of
the area.
Overnight lows Thursday night into Friday morning will be in the
single digits above and below zero range again with some clearing
and light and variable winds that become light out of the
southwest. Wind chill values will range from 5 to 15 below zero.
Confidence is low, but there may be some locations that could dip
briefly down to wind chill advisory criteria overnight Thursday
night into early Friday morning.
The cold air begins moving out of the region on Friday and Friday
night as another short wave trough aloft sweeps across the region
and the upper ridge over the western U.S. approaches from the west.
.LONG TERM...(Saturday through Wednesday)
Issued at 150 PM MST Wed Feb 23 2022
For this long-term forecast period, the weather is looking much
better in terms of warmth and the lack of wintry precipitation. The
Tri-State Region will reside between split flow, or between the
northern and southern jet streams. This will keep any impactful
weather systems well north or south of the forecast area. That being
said, fire weather parameters will need to be monitored as a result
of the forecast warmth, particularly for Tuesday and Wednesday when
winds are higher.
For this weekend, no weather concerns are currently anticipated. The
warming trend that begins on Friday shall continue throughout the
weekend. Afternoon high temperatures Saturday should rise into the
40s, while Sunday will bring afternoon high temperatures in the 50s,
approaching 60 in some locales. West winds of 10-15 mph are
currently forecast, so overall the fire threat should be low
although if stronger winds are forecast or observed for Sunday, it
is possible that near-critical fire weather conditions are observed.
Currently though, based on other forecast parameters that factor
into fire weather forecasting, it does not appear Sunday will be a
fire weather day.
Going into next week, the warming trend will take a brief pause
Monday before continuing for Tuesday and Wednesday. Forecast
guidance indicates a lee trough should take shape along the Front
Range Tuesday. As this trough forms, warm air will advect in from
the southwest, pressure gradients will tighten, and winds should
increase. This, along with persistent dry weather and dry air
advection into the region, could set the stage for a few fire
weather days, particularly on Tuesday and Wednesday. There is still
some uncertainty in the forecast this far out as guidance varies
depending on which model is utilized. However, the general upper
level pattern would favor fire weather potential so will continue
mention of potential fire weather conditions for middle of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 428 PM MST Wed Feb 23 2022
VFR to MVFR conditions forecast. Low clouds will move in tonight
with the light snow. Am not expecting the snow to be much of an
impact. The snow will end from southwest to northeast.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Wind Chill Advisory until 8 AM MST /9 AM CST/ Thursday for
KSZ001-013-027-041.
CO...Wind Chill Advisory until 8 AM MST Thursday for COZ090>092.
NE...Wind Chill Advisory until 8 AM MST Thursday for NEZ079.
&&
$$
UPDATE...JTL
SHORT TERM...LOCKHART
LONG TERM...RRH
AVIATION...JTL
Area Forecast Discussion
National Weather Service Green Bay WI
516 PM CST Wed Feb 23 2022
Updated aviation portion for 00Z TAF issuance
.SHORT TERM...Tonight and Thursday
Issued at 333 PM CST Wed Feb 23 2022
The latest RAP analysis and satellite/radar imagery show scattered
to broken daytime convective clouds spreading south off Lake
Superior early this afternoon. Light snow showers continue over
northern Door counties, but these should diminish by the start of
the evening as low level winds back around to the west.
Otherwise, arctic high pressure was centered over the northern
Plains and slowly drifting towards the region. The next storm
system is taking shaping over the desert southwest and is poised
to impact the region on Thursday. Forecast snow timing and amounts
are the focus in this part of the forecast.
Tonight...The arctic high pressure will slide towards the state
slowly. As the desert southwest system ejects into the western
Plains late, mid and high clouds will be increasing overhead.
Cloud heights will generally remain above 10 kft so most of the
region will remain dry. The exception will be near the Lake
Michigan shoreline, where a convergence zone will develop in lake
induced troughing. With strengthening northeast or east synoptic
flow, a mid-lake snow band remains projected to shift towards the
northeast WI shoreline after midnight. The highest chance
continues too look like areas over southeast Kewaunee and
Manitowoc counties where around a half inch could fall by 6 am
Thursday. Low temps could fall quickly over the northwoods this
evening before clouds increase late. Lows to range from around 10
below to 15 below over Vilas county to 10 to 15 above over east-
central WI.
Thursday...The lake snow band will gradually lift northwest over
the course of the day, possibly moving into southeast Door county
in the afternoon. High resolution guidance doesn`t portray a
relatively strong band, and the movement should also limit
potential accumulations. Snow amounts along the lakeshore could
reach to around 1 inch by the end of the afternoon. Meanwhile,
increasing upper divergence and backing mid and upper flow will
support an area of light snow moving into the region from the
southwest to northeast in the afternoon. Thermal profiles are
favorable for dendritic snow growth thanks to a deep isothermal
layer. This should result in high snow ratios that could push
accums up to 1 inch over parts of central Wisconsin by 6 pm
Thursday. Will hold off on a winter weather advisory for tomorrow
considering forecast amounts may only reach or slightly surpass an
inch by 6 pm Thu. High temperatures will range from the mid teens
in the north to low 20s in the south.
.LONG TERM...Thursday Night Through Wednesday
Issued at 333 PM CST Wed Feb 23 2022
Main focus of the long term will be the snow totals and possible
headlines for the accumulating snow Thursday night into early
Friday. Otherwise, fairly quiet late February weather is expected
as the upper flow turns west/northwest, with only a couple weak,
fast moving clipper-type systems pushing across the Great Lakes.
Temps will be below normal on Friday, then near or slightly above
normal readings this weekend into early next week.
Thursday night into Friday...expecting a light to moderate snow
event for most of the area, with the exception being far north
central WI where little to no snow is expected. Expect the forcing
associated with the deformation band over central WI to wane in
the evening, and re-focus farther south and east as the surface
low passes well to our south and a sharp mid-upper level trough
crosses the area. Period of impressive forcing within the DGZ,
especially over east central WI, where the DGZ spans from
2,000-12,000 ft for a time. This will combine with some lake
enhancement from Lake Michigan with favorable delta Ts and
inversion heights. Snow ratios of 20+ are expected at times, where
these features overlap. Boundary layer winds become more
northerly after midnight, which will keep the enhancement over the
lake later in the night. As it looks now, where the best lift/QPF
occurs, an advisory snow is likely, mainly over the far southeast
CWA. However, after collaboration with surrounding offices, we
will hold off on an advisory for now. Thinking central WI will
stay just below criteria, and east central WI won`t see the more
significant impacts until later Thursday evening. Northeast to
north winds will gust up to 25 mph will create some minor blowing
and drifting. Everything wraps up by around 12z Friday with only
some lingering light precip possible in the morning before drier
air works in. Lows look to drop below zero over north central WI,
with single digits to lower teens across the rest of the area.
Highs will be upper teens to middle 20s.
Rest of the long term...flow turns westerly on Saturday then
northwest on Sunday. Quiet weather is expected. Southwest to west
winds will get gusty on Saturday, as the gradient tightens up
ahead of a frontal boundary, with gusts to 30-35 mph expected. The
front looks to come through mainly dry, with only a few light
showers possible, mainly over northern WI. The next shortwave and
associated clipper system will take aim across the area later
Monday. Still too many differences in timing and location for the
model blend to include chances, but some snow chances will
eventually need to be added.
&&
.AVIATION...for 00Z TAF Issuance
Issued at 516 PM CST Wed Feb 23 2022
Light snow showers over Vilas and northern Door counties will
diminish as low level winds back around to the west this evening.
Generally quiet weather is expected from this evening through the
rest of the taf period. Mid and high clouds will increase across
the region ahead of the next storm system overnight into Thursday
morning. The most uncertainty revolves around evolution of a snow
band as it drifts into northeast WI off Lake Michigan late
tonight into Thursday morning. The latest high resolution models
show the band arriving late tonight into Thursday morning. There
is some potential for MVFR/IFR vsbys as the snow arrives, but it
should be moving and therefore tried to handle the scenario with a
tempo. Light snow will generally overspread the area on Thursday
afternoon and should expect deteriorating conditions after 18-20Z.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......Bersch
AVIATION.......Kurimski
Area Forecast Discussion
National Weather Service Grand Rapids MI
Issued by National Weather Service Northern Indiana
622 PM EST Wed Feb 23 2022
LATEST UPDATE...
Aviation
.DISCUSSION...(This evening through next Wednesday)
Issued at 255 PM EST Wed Feb 23 2022
Persistent lake effect snow showers have come to an end across the
bulk of the region by late this afternoon thanks to a gradual
weakening and shift in winds to more northerly. Exception has been
along the lakeshore (particularly Ludington) as satellite and obs
have shown little change in that nearshore band. Expectation is more
of the same at least through the evening commute until winds turn
more northeasterly around/after 00Z cutting off lake moisture. While
some lingering cloud will prevent a bottoming out of temps tonight,
light northeast flow leads to a chilly night as lows drop into the
teens with single digits possible north of US-10.
Mid/upper level trough over the intermountain west ejects east into
the southern Plains late tonight reaching the mid-Mississippi valley
by Thursday evening. Baroclinic zone currently draped from the Ohio
Valley into the Ozarks is drawn northward toward lower MI in
response to this wave as associated cyclogensis occurs across the
Tennessee/Ohio Valleys. Newly formed surface low pressure advances
into southern OH Thursday evening allowing the leading edge of
isentropic ascent to reach the I-94 corridor by 00Z Friday with
light snow overspreading the remainder of the CWA by 06Z. High
consensus among the deterministic runs this morning for the main
ribbon of PV/mid-level to cross west MI between 09Z and roughly 12Z
Friday morning. PV wave likely enhances the persistent isentropic
ascent with additional forced ascent leading to a modest uptick
snowfall rates with internal probabilities showing a increase in
chances of rates approaching or reaching 0.5"/hr for areas south of
US-10 in the 09-12Z timeframe. Snow ratios also look to increase in
this period as winds turn northerly on the backside of the low
drawing colder air back into the region. 850mb temps drop from -8 to
-10C around midnight down to -13 to -15C by 7AM Friday. Strong CAA
cools to column with forecast soundings showing deep layer
saturation between 900-700mb dropping into the DGZ enhancing ratios.
That said, limiting factor will be available QPF which only looks to
be 0.10" or less. NAM and RAP have been most aggressive on rates at
snow onset (of 0.25"-0.5"/hr) late Thursday (~00-03Z) evening
along/south of a Kalamazoo-Lansing line owing to elevated frontal
forcing along the edge of the baroclinic zone. Overall total
accumulations of 1 to 3 inches are possible (lowest amounts toward
the northern CWA) though wouldn`t rule out a local 4" amount south
of the Kzoo-Lansing line if the initial rates late Thursday
evening come in higher like what the NAM/RAP suggest.
System clears west MI by 15Z Friday morning ending synoptically
forced snow. Lake aggregate troughing over Lake Michigan lingers
through the rest of the day Friday allowing for some lake effect
snow showers to persist into Friday evening. Winds first half of the
day will be out of the north favoring bands being confined near the
lake shore. As high pressure builds into the region from the central
Plains, winds back to northwest/west northwest Friday afternoon
evening increasing potential for snow showers to move further
inland. High pressure should become established enough to taper off
any lingering lake effect by Friday night. Temperatures slowly
moderate over the course of the weekend as the arctic airmass pushes
east. Another arctic front drops through the region late Sunday
however is still expected to be a dry fropa. This airmass currently
looks to glance west MI with the core staying to our north and
east.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 612 PM EST Wed Feb 23 2022
High pressure arrives tonight and then vacates the area during the
afternoon hours tomorrow allowing a rise of CIGs out of MVFR and
into VFR for the southern TAF sites during the first few hours of
the TAF period. Then, expect CIGs to fall again and a chance for
precipitation to arrive during the last few hours of the TAF period,
but will let the next forecaster time out the precip with the next
TAF forecast. Winds will be veering more easterly and then
southeasterly ahead of the approaching low pressure wave through the
forecast period.
&&
.MARINE...
Issued at 255 PM EST Wed Feb 23 2022
Small Craft Advisories remain in effect through late this evening
before gusty onshore north/northwesterly flow and elevated waves
gradually subside as high pressure expands eastward from the upper
Midwest into the northern Great Lakes. Winds will veer more easterly
in direction and be moderate in strength Thursday in response to
developing low pressure ejecting out of the mid-Mississippi Valley
and eventually into the northern Ohio River Valley Thursday night
into Friday morning. This low will bring a round of snowfall to all
of the nearshore waters. Behind the departing low, strong high
pressure will settle into the central Plains with low pressure
traversing eastward towards Hudson Bay. Onshore winds backing to the
west will increase with a tightened pressure gradient leading to
likely small craft conditions for the weekend in ice free areas.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Small Craft Advisory until 10 PM EST this evening for LMZ844>849.
&&
$$
DISCUSSION...KDK
AVIATION...Roller
MARINE...IRL
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1039 PM EST Wed Feb 23 2022
.SYNOPSIS...
A nearly stationary front will linger over our region through
early Friday. The next big low pressure moves northeast along the
front Thursday and Friday bringing more rain chances mainly for the
mountains. The front is forecast to cross our area late Friday with
dry and cooler conditions prevailing into Saturday. Another low
could move up from the Gulf on Saturday and Sunday, with more
precipitation, including possible mountain snow. Expect drier
conditions next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 1036 PM EST Wednesday: Dense fog has been settling in
across the area from the Lakelands and lower Piedmont of SC up
across the outer reaches of the Charlotte metro area. This area
held onto the cloud cover past peak heating this past afternoon,
thus didn`t have as far to go to cool off to saturation once the
clouds thinned and the sun went down. In fact, some locations over
the nrn Upstate have already cooled below their fcst low temps by
a few degrees, altho guidance insists the temp might actually rise
a bit overnight. Visibility has been more steady over the past
hour, and the near term guidance has picked up the signal with
indications the dense fog will stick around through daybreak. So,
we have issued a Dense Fog Advisory now instead of dumping in the
lap of the next shift. The fog should start to mix out over the
NC Piedmont first, perhaps before sunrise.
Otherwise, rain chances look to increase near daybreak across
western NC and portions of NE Georgia and the SC Upstate. However,
CAMs are not in good agreement regarding the placement of
rain overnight into Thursday. The HRRR and ARW show PoPs
increasing across much of the CWA early Thursday morning into
Thursday afternoon whereas the NAM and FV3 have a few scattered
showers across the CWA, but keep most of the rain to our north
and west. This leads to lower confidence than usual regarding
PoPs through the near term period. Capped PoPs to likely across
the far northern NC counties, with slight chance to chance PoPs
elsewhere. With sfc high pressure extending into the area from New
England on Thursday, winds will become NE`ly allowing cold air
damming to develop. This will lead to a tricky high temperature
forecast. Temps look to be the coolest across the western NC
Piedmont and northern NC mountains. Highs should be near to a few
degrees below normal across the NC Piedmont, with above normal
temps expected elsewhere. High temps will be monitored closely
and will likely need to be adjusted as needed to account for the
CAD on Thursday.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 200 pm EST Wednesday: The period will begin Thursday evening
with a wedge front draped solidly across the northern half of the
forecast area. There will likely be some light residual southerly
upglide ongoing over the surface damming layer, and at least chance
PoPs will be needed early to account for this. The numerical models
have the wedge layer retreating northward overnight, but it is
always questionable how much airmass recovery occurs during the
nighttime hours without a scouring mechanism. At any rate, will pare
back PoPs overnight east of the mountains. Meanwhile, a surface wave
lifting along the central Appalachians Thursday night will drag a
trailing cold front into the southern Appalachians around daybreak
Friday, where PoPs will ramp back up to likely before 12Z. Most of
the deeper moisture along the frontal zone trails the cold front,
and QPF is expected to diminish as the system transits the mountains
Friday morning. Will thus diminish PoPs quickly east of the
mountains with the fropa. Cannot rule out some weak pockets of
instability in the lower Piedmont with a midday fropa, but chances
of convection appear very limited. The fropa should be delayed long
enough for plenty of low to mid 70s temperatures to occur east of
the mountains Friday.
Falling heights upstream over the plains will then work quickly to
reactivate upglide moisture over the stalling frontal zone, with
light precipitation possibly returning to the southern Appalachians
by Saturday. At the very least, returning clouds should cap maximum
temperatures below climo.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 200 pm EST Wednesday: Confidence is fairly low on the PoPs,
QPF, and potential wintry mountain ptypes for the latter half of the
upcoming weekend. The GFS remains faster and more aggressive on the
moisture return along the activating front, with the best deep
moisture and QPF slated for primarily Saturday night through Sunday.
The ECMWF delays the better QPF until Sunday. Neither solution is
particularly cold, with just the higher ridges of NC mountains
seeing much of a snow chance as the moisture returns. The Canadian
remains the driest solution, with the stalled frontal boundary
suppressed farther south, and ensemble members are quite varied.
Will thus leave late weekend PoPs capped in the solid chance range
for now.
The ECMWF continues to feature low pressure development over the
coastal waters on Monday, but it has trended weaker and farther
southeast. The GFS has much less development and is drier, so a dry
forecast is maintained either way for Monday. Dry high pressure will
persist on Tuesday as a surface high slips off the East Coast. A
backdoor cold front should move southward through the region on
Wednesday, but any moisture looks quite sparse with this
boundary. Temperatures will be near climo through the period.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: VFR for the most part through the evening
hours, although MVFR lurks to the S/E of KCLT. Low clouds will
expand/redevelop during the early morning hours as low level
moist upglide starts to develop. As a result, a low cloud deck
should grow rapidly, perhaps initially at the MVFR level, but
will quickly drop to IFR/LIFR at most terminals before the start
of operations Thursday morning. There is some debate about the
coverage of light precip on Thursday morning, but the precip
will be light rain/drizzle and of secondary importance to the
low clouds and fog. Will use a TEMPO to describe the worst of
conditions from daybreak through mid-morning, which should be LIFR
at most terminals, but could be VLIFR at times. The development
of light precip over the top of a developing wedge boundary will
help to cool the air mass to the north of the region and drive
this boundary southward in the afternoon, which will lock in the
IFR conditions across the region.
Outlook: A relatively active pattern will remain in place through
the work week with associated flight restrictions. A lull is
expected to develop Friday with conditions returning to VFR into
early Saturday before another storm system enters the area with
likely flight restrictions late Saturday into Sunday.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...Dense Fog Advisory until 8 AM EST Thursday for NCZ068>072-082.
SC...Dense Fog Advisory until 8 AM EST Thursday for SCZ006>014-019.
&&
$$
SYNOPSIS...DEO
NEAR TERM...AP/PM
SHORT TERM...HG
LONG TERM...HG
AVIATION...PM
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
854 PM EST Wed Feb 23 2022
.UPDATE...
Issued at 854 PM EST WED FEB 23 2022
Temperatures are running cooler across the area this evening, with
lower 30s having penetrated west of I-75, along portions of the
Mountain Parkway, and near the I-64 corridor. Light precipitation
has also been making it further east than forecast, and despite
some drier air to overcome, some of the highest resolution model
guidance has been indicating a window of enough saturation up
north to allow for a better chance of measurable precipitation.
Consequently, this will allow for a little more in the way of
freezing rain across the northwest portion of the area. Most of
the guidance is running too warm, so have relied more on the HRRR
idea, which keeps temperatures fairly steady through the night.
This seems reasonable, as northeast flow is maintained in the
lower levels through at least early Thursday. Warm ground
temperatures will prevent any significant impacts; however, some
light glazing will be possible on elevated surfaces. It is also
possible that a few higher elevation bridges and overpasses could
pick up some light glazing, allowing for a few slick spots. As
such, have issued a Special Weather Statement mentioning these
concerns, again, generally west of I-75 and through portions of
the Mountain Parkway and near the I-64 corridor. Updates have been
sent.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 529 PM EST WED FEB 23 2022
Despite strong arctic high pressure over the northern plains
sending colder air into our region and ending significant precip,
skies remained cloudy all day, with low level moisture trapped in
the frontal inversion on the upwind side of the Appalachians.
Radar also shows drizzle persisting. The drizzle may shrink toward
the southeast this evening, but clouds will persist until the next
system moves in.
That next system is already underway to our west and southwest. A
cold front is laid out from just east of the central Appalachians
to the southern tip of TX. Flow off the gulf is overriding the
shallow cold air mass in the Deep south and then getting picked
up by flow aloft and riding northeast on isentropic lift on the
east side of a large mid/upper level trough centered over the
western CONUS. This has resulted in precip breaking out as far
east as western KY late today. This precip will continue to
develop eastward tonight, affecting at least our southern counties
by morning, and then spreading north. If it reaches our northern
counties soon enough (overnight or early Thursday), freezing rain
could result, with temperatures there expected to be at or just
below freezing at that time. However, there is a question of
whether it gets there that early, and whether or not anything but
elevated surfaces would manage to accumulate light ice. For that
reason, at this time it does not look terribly significant, but it
will need to be watched.
The heart of this mid/upper level trough is ejecting to the east
northeast and will support development of surface low pressure
over the lower Mississippi Valley on Thursday, which will
track/develop quickly north northeast to the region of western
NY/PA by early Friday morning. This will bring the initial area of
precip north through eastern KY during the day Thursday, with a
break arriving from south to north during the course of the day.
The system`s cold front then plows through from northwest to
southeast during the night with another round of rain.
There is a risk of hydro problems once again with this system.
The greatest risk is in our southern and central counties where
the heaviest rain fell in the last system, and where the heaviest
totals are also expected out of this one. Another factor is the
potential for weak instability and convection. For these reasons,
a Flood Watch has been issued for all but the northern portion of
the forecast area. The back edge of the main precip should be in
southeast KY and heading southeast early Friday morning,
.LONG TERM...(Friday through Wednesday)
Issued at 234 PM EST WED FEB 23 2022
The start of the extended begins with the tail-end of a system that
is expected to bring widespread precipitation. The associated cold
front is progged to cross through the area early Friday afternoon
but ongoing rain and maybe a few rumbles of thunder will be possible
for early Friday morning. Temperatures are expected to drop behind
the front due to CAA; however, daytime highs for Saturday are
expected to recover back into the mid-40s. Models continue to hint
at another system that is forecasted to skirt the area late Saturday
night into early Sunday morning. In recent model runs, deterministic
models have this system taking a more southerly track and missing
the forecast area but opted to keep PoP across the southern zones.
With the timing of the system, precipitation looks to be messy as
snow changing to rain-snow, to all rain is possible before ejecting
out of the area. Accumulations look to be minor if any accumulation
at all. If they`re are any accumulations, it could happen on the
highest terrain across the south. After the weekend system ejects,
zonal flow remains over the area. This will keep seasonal
temperatures and dry weather across the region. However, models
begin to diverge on toward the end of the period with respect to
another system that`s expected to impact the forecast area for
Tuesday into Wednesday. Did opt for the drier solution in the
forecast grids for this even as confidence is extremely low.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 854 PM EST WED FEB 23 2022
Mainly IFR or lower conditions will be the rule through the
majority of the period, with the exception at KSYM, where MVFR
conditions will be maintained through much of the forecast. Light
precipitation will move in overnight from the west. Some light
freezing will be possible mainly along and northwest of a line
from KSYM to KSME, with some glazing possible on elevated
surfaces. More sustained rainfall will move in from the southwest
on Thursday, with temperatures warming above freezing. The rain
could be heavy at times. Northeast winds of 5 to 8 kts will veer
to the east and southeast by late Thursday.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
Flood Watch from midnight EST tonight through Friday morning for
KYZ058-068-069-079-080-083>088-107>120.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...HAL
LONG TERM...VORST
AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
958 PM CST Wed Feb 23 2022
.UPDATE...
Issued at 949 PM CST Wed Feb 23 2022
We have had a lot of debate this evening on putting a Winter Weather
Advisory up for Thursday afternoon, with the HRRR and other CAMs
showing the potential for a band of 3-4" of snow from roughly Eau
Claire back to Waseca. However, we decided to remain headline free.
The biggest reason is snowfall amounts this high are highly dependent
on snow ratios being much greater than climatology (13:1). Though
HRRR outputs over 3" of snow at EAU and ACQ, BUFKIT snow amounts
using the Cobb technique are about an 1" lower. In fact, all BUFKIT
soundings from south central MN into western WI are showing snow
totals of just 1-2", indicating our snow ratios may be overly
optimistic as much of our sounding is actually colder than the DGZ,
with the strongest lift (per omega profiles) well above the DGZ. When
this happens, you tend to get very fine crystals, with a snow ratio
that often stays down in the 10-12:1 range. With HREF probabilities
for 1" per hour snow rates at 0%, there`s just not enough support out
there to change our going non headline stance.
&&
.DISCUSSION...(This evening through Wednesday)
Issued at 258 PM CST Wed Feb 23 2022
KEY MESSAGES:
- 1 to 3 inches of snow is expected from the Twin Cities south and
eastward Thursday.
- Return towards average temperatures early next week.
A mid level cloud deck is approaching the area this afternoon ahead
of a surface low that will pass far to our south through tomorrow.
Increasing cloud cover and light winds will allow us to only brush
Wind Chill Advisory criteria for our far northwestern counties
overnight, so have opted to hold off on any headlines. Even though
we will be on the northern edge of the aforementioned system,
sufficient mid level forcing coupled with a 500mb shortwave moving
into the Dakotas by late Thursday morning will allow for some light
snow to develop. The main challenge with this forecast is determining
where a potential fgen band will set up and lead to increased snow
totals. Snow ratios are another deciding factor in snow amounts.
Nudged ratios up to 20:1 with a deep DGZ across southern Minnesota,
but it`s possible they could end up being closer to 25:1. Overall,
snowfall totals will range from 1 to 3 inches, with confidence
quickly dropping off for higher amounts. It is worth noting that
there has been a slight upward trend in QPF/snow totals and this
could end up being a low end Winter Weather Advisory event, but have
decided to hold off for now. Snow will continue from early Thursday
afternoon until eventually tapering off overnight.
The remainder of the period will be dry with below normal
temperatures continuing through the end of the week. We`ll see highs
near average Saturday before a brief dip Sunday with a signal for
warmer temperatures on the horizon as we head into March.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 526 PM CST Wed Feb 23 2022
Expect snow to overspread all MPX terminals, with the northwest edge
of a broad snow shield expected to get all the way up to AXN in the
afternoon. A burst of heavier snow, with visibilities as low as
1/2sm may impact RWF/MKT/MSP/RNH/EAU. We`ve seen a slowing trend with
recent models for snow onset. Spread for snow onset is about 2
hours and have onset timing close to what the HRRR has. Winds will
be light and variable overnight, becoming northeasterly Thursday,
though with speeds under 10 kts.
KMSP...Did slow snow onset some, with the RAP/GFS/NAM all showing
snow starting after 18z, with a slowing trend noted in the GFSlamp as
well. Expect snow to start between 16z and 19z. Between 19z and 23z,
we could see some periods with a vis down to 1/2sm in snow, but left
that potential out for now this far out with confidence in that
occurring not high enough.
/OUTLOOK FOR KMSP/
Fri...Mrng MVFR cigs, bcmg VFR. Wind WSW 5-10 kts.
Sat...VFR. Wind SW 10G25 kts.
Sun...VFR. Wind N 5-10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
UPDATE...MPG
DISCUSSION...Dye
AVIATION...MPG
Area Forecast Discussion
National Weather Service Nashville TN
555 PM CST Wed Feb 23 2022
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Went ahead and updated the forecast as temperatures particularly
in the northwest were too warm by 5 or 6 degrees. HRRR seems to
be handling the shallow cold air the best so temperatures were
adjusted with more weight put toward the HRRR solution. Looking at
model soundings, the northwest part of our area will likely see
some sleet and freezing rain this evening with the onset of
precipitation. Temperatures are expected to warm a couple degrees
overnight in the northwest allowing all precipitation to switch to
rain. It is possible that some vehicles and elevated surfaces
could develop a glaze in the far northwest, otherwise, no
accumulations or impacts are expected.
As far as rainfall amounts with this wave of precipitation, 1-2
inches of rain is possible which could cause creeks and rivers to
rise again given the saturated ground conditions and already
swollen bodies of water. The flood watch goes in effect at 6 PM.
&&
.AVIATION...
00Z TAF DISCUSSION.
BNA/MQY/CKV/CSV...Middle Tennessee remains north of a surface
trough extending out of the Gulf of Mexico. Temperatures therefore
remain quite cold across the mid state owing to a persistent north
wind, and low stratus and fog have stuck around a good part of
the day. An area of precipitation is currently making its way
across the Tennessee River, and some of this precipitation is
going to start off as freezing or frozen, especially at CKV.
Temperatures will gradually warm overnight as the aforementioned
surface boundary lifts northward and focuses the most intense
precipitation band across northern Middle Tennessee. So look for
rain to settle in this evening and continue throughout Thursday
with persistent IFR/LIFR ceilings.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
Flood Watch through late Thursday night for Cannon-Cheatham-Clay-
Cumberland-Davidson-De Kalb-Dickson-Fentress-Hickman-Houston-
Humphreys-Jackson-Lewis-Macon-Maury-Montgomery-Overton-Perry-
Pickett-Putnam-Robertson-Rutherford-Smith-Stewart-Sumner-
Trousdale-Wayne-White-Williamson-Wilson.
&&
$$
DISCUSSION......Reagan
AVIATION........08
Area Forecast Discussion
National Weather Service Phoenix AZ
524 PM MST Wed Feb 23 2022
.UPDATE...Updated Aviation Discussion.
&&
.SYNOPSIS...
A storm system moving across the area today will bring lower
elevation rain, mountain snow, gusty winds, and well-below normal
temperatures. More tranquil weather conditions are then expected
beginning Thursday and continuing through the rest of the forecast
period with temperatures gradually moderating.
&&
.DISCUSSION...
Latest water vapor imagery as well as objective analysis are now
short the deep upper low center that is bringing a variety of
weather conditions to our CWA is now moving across SE CA and is
expected to move into NW AZ shortly. A 90 kt jet max at 500 mb is
now moving in the southern AZ, with good mid-level diffluence
ahead of the main low center across most of AZ. The associated sfc
cold front has now moved into eastern Maricopa/NW Pinal counties.
Along/just behind the sfc front, widespread rainfall has occurred
over much of South-Central AZ with rainfall amounts in the
0.25=0.50 inch range being reported so far. Lesser rainfall
amounts have been reported across SW AZ/SE CA, mainly 0.10 inch or
less across SW AZ and 0.00-Trace across SE CA. latest 88-D radar
output is currently showing the heaviest/steadiest rain now moving
into southern Gila/NW Pinal/extreme eastern Maricopa counties with
some showers still falling from central/western Maricopa county
westward all the way thru SW AZ/SE CA. Along with the rainfall,
much cooler air has spread across south-central AZ. Phoenix Sky
Harbor fell from a temp of 56 degrees shortly after midnight down
into the mid-40`s at this hour. Given the very cold airmass (850
mb temps around 0C on latest high-res guidance), snow levels are
also quite low, with reports of flakes in the air at elevations as
low as 2700 feet over far-north Scottsdale being reported.
Further to the west, breaks in the clouds have allow temps to rise
into the 50`s.
As far as the short-term forecast is concerned, latest HRRR high-
res model forecasts are indicating that the band of heaviest
rain/snow will progress eastward across eastern AZ this evening,
then into western NM late tonight. NBM QPF guidance is showing
anywhere from 0.50 to 1.25 inch across southern Gila county this
evening. Given the continued low snow levels (3000-4000 ft),
confidence remains high that at least a few inches of snowfall
will occur above 4000 feet, with amounts as high as 12 inches over
the highest peaks. Given the low snow levels, runoff into area
streams/washes should be kept in check, with the forecast for
Tonto Creek nears Roosevelt now remaining below Action Stage.
Further to the west, athough a gradual drying/clearing trend is
expected to continue thru the rest of the afternoon/evening, some
additional shower activity could occur that could add a few more
hundredths of an inch to the buckets. There is still a slight
chance that a isolated TS could occur as well (10-15%) thru the
rest of the afternoon/early evening, given the still-unstable
forecast soundings (150-250 J/kg of CAPE) and breaks in the cloud
cover allowing temps to locally warm a bit. Any storms that do
occur could briefly lower freezing levels, perhaps allowing a bit
of small hail/graupel to reach the ground across the lower
elevations of south-central AZ. Along with the hail/graupel,
locally gusty winds could also occur, with speeds as high as 35
kts possible.
AS far as the forecast is concerned for late tonight thru Friday,
the much colder than normal daytime high temperatures will set
the stage for a couple of very cold early mornings both Thursday
and Friday. The combination of clear skies and light winds will
cause temperatures to dip to around freezing across many of the
rural communities, especially across La Paz County
tonight/Thursday night and NW Pinal County on Thursday night.
Across the Phoenix area, early morning temperatures in the middle
to upper 30s are expected both days.
A return to a more tranquil weather pattern is then expected as we
head towards the end of the week and into the weekend. After the
passage of the storm system today, heights aloft will be on rise
during the next several days as a ridge over the eastern Pacific
moves into the west coast. A shortwave trough will move across the
intermountain west Friday into Saturday and remain northeast of the
area. No impacts are expected from this system other than possibly
some enhanced northerly breezes along the Lower Colorado River
Valley, especially on Saturday, when wind gusts in excess of 20 mph
are possible. By Sunday and continuing into most of next week, there
is good agreement amongst the ensemble cluster analysis of ridging
aloft taking hold across the western CONUS.
As the heights aloft rise through the end of the week and into
the upcoming weekend, temperatures will gradually rebound back to
near normal levels with above normal readings likely through most
of next week. In fact, NBM probabilities for temperatures of
greater than 80 degrees for Phoenix is greater than 60% from
Tuesday onwards, with the probabilities at greater than 80% for
southeast California.
&&
.AVIATION...Updated at 0010Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Rain showers, low CIGS, and reduced visibility remain the top
aviation weather concerns early this evening. Bands of light to
moderate showers, and areas of more isolated showers, will
continue to move through the terminal area until approximately
01-03z this evening. A slight 15% chance of isolated showers
(VCSH) will also linger until this evening at 06Z. Cigs will
generally stay between 4-6 kft through early evening with
temporary lower cigs between 2-3 kft during shower activity.
Visibility will be reduced to 2-5 SM during showers depending on
rain intensity. All of these conditions should improve fairly
quickly after 01-02z this evening. Otherwise, W component winds
will prevail while speeds decrease to AOB 7 kts this evening after
03-04Z. Early Thu mroning there is a ~20-35% chc of FEW low clouds
forming at 1-2 hft and occasional limited vsby of 2-5 SM in
developing patchy morning fog between 13-16Z. Otherwise there is
uncertainty regarding wind directions and the timing of any shifts
later tonight through early afternoon Thu, but speeds will be
light by then AOB 6 kts with clear to mostly clear skies.
Southeast California/Southwest Arizona including KIPL and KBLH:
Showers in the vicinity and lingering low cloud CIGs AOB 6 kft
will persist early this evening until about 03-04Z at the
terminals. At KIPL, strong W winds with gusts of 15-30 kts will
last until about 07Z tonight. At KBLH, very breezy W winds with
gusts of 22-27 kts are also expected until 03-04Z. Slightly lower
visibilities AOA 6 SM in patchy light fog is also probable for
KIPL on Wed morning. Otherwise lighter winds and clear to mostly
clear skies will take over.
&&
.FIRE WEATHER...
Friday through Tuesday:
Below normal temperatures are expected on Friday, climbing to near
normal on Saturday, and then above normal the rest of the period.
A dry disturbance will result in enhanced breeziness late Friday
into Saturday, with gusts in excess of 20 mph possible, mainly
along the lower Colorado River Valley area. Otherwise, mainly
light winds will prevail during the rest of the period. Min RH
values will range between 10-20% with overnight RH values
recovering to between 30-60% across eastern districts and
between 20-35% across western districts.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Winter Weather Advisory until 11 PM MST this evening for AZZ545-
557-558-562-563.
CA...None.
&&
$$
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DISCUSSION...Percha/Lojero
AVIATION...Sawtelle/12
FIRE WEATHER...Lojero
...Update to aviation forecast discussion...
.DISCUSSION...
Issued at 222 PM CST Wed Feb 23 2022
Key messages:
- Light wintry precipitation impacts the morning commute Thursday
towards far eastern Kansas.
- One final chilly afternoon Thursday before sun and warmer temps
return this weekend into next week.
Mid to high level clouds continue to stream across eastern Kansas
this afternoon, as the associated midlevel clipper system translates
into the Mississippi Valley. Reports of snow and sleet with this
system are just to our south near Chanute as the precip shield lifts
northeast into southern Missouri. This evening is cool and dry as
the next southwesterly upper trough lifts into the central plains by
Thursday morning. Similar to previous forecasts, models are
consistent on the weak and narrow area of lift in the 600-700 mb
layer that quickly moves east of the area by mid afternoon. Forecast
soundings vary somewhat in the moisture availability, particularly in
the dendritic growth layer over far eastern Kansas where light snow
may mix with light freezing drizzle. The HRRR and RAP past runs are
more pronounced with this scenario along and southeast of I-35 while
consensus leans more towards a shallow and very cold profile below
700 mb, similar to Tuesday morning where snow was observed. Overall
snow accumulations through Thursday afternoon are an inch or less,
despite some ensemble members clustering close to 2 inches. After
collaboration with surrounding offices, opted to hold off on an
Advisory headline and will evaluate later this evening as this
event has the potential to cause hazardous travel for the morning
commute.
One final day of lows in the teens and highs in the 20s Thursday
before the upper pattern transitions to dry northwest flow aloft,
signaling warming and dry conditions likely. Above freezing,
downsloping air arrives in time for the weekend as highs warm from
the 40s Saturday to upper 50s on Sunday. Similar pattern persists
into next week allowing temps to peak in the middle 60s once again.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 530 PM CST Wed Feb 23 2022
High clouds are continuing to filter in from the southwest as a
system off in northwest Arkansas moves eastward. VFR conditions
will continue overnight but by Thursday morning, expect MVFR
ceilings to move in around 14z as light snow will begin to fall
at all terminals. This snow could limit visibilities a bit, but
should stay MVFR at the worst. Snow showers will begin to end in
the area by 4-5 pm with visibilities and ceilings raising back to
VFR criteria. Winds should remain light around 10 knots or less
throughout the TAF period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...22
AVIATION...Griesemer