Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/12/22
Area Forecast Discussion
National Weather Service Birmingham AL
725 PM CST Fri Feb 11 2022
.UPDATE...
Evening Update and 00Z Aviation.
&&
.SHORT TERM...
/Updated at 0634 PM CST Fri Feb 11 2022/
A double frontal structure was just northwest of Central Alabama
this evening. The latest surface map has 40s and 50s dew points
just south of the area. As we head into the overnight hours, we
will have increasing near ground level moisture over a cool
ground. This will promote the development of some fog and low
clouds after midnight. The specific placement is still being
worked on, but mostly likely will spread northward south of I-20.
Some of the fog may become dense in places. Will monitor another
hour or so and may add some mention into the HWO overnight. The
clouds and fog will be relatively short lived as the cold front
moves into the north half of the area Saturday. Some mixing will
also take place after sunrise.
75
Previous short-term discussion:
/Updated at 1142 AM CST Fri Feb 11 2022/
Through Saturday.
Features of Interest.
A longwave trough extended from over Southern Canada southwest to
over South Texas. Surface high pressure was centered off the
Southeast Atlantic Coast while a sharp cold front extended from
surface low pressure over the Great Lakes and extended southwest
into Northern Texas.
Today.
A shortwave trough will move over the area in dry fashion this
afternoon, ahead of the longwave trough diving southeast over the
Central Plains. The pressure gradient between an approaching cold
front from the northwest and surface high pressure to the
southeast will result in breezy conditions from the southwest at
times this afternoon.
Expect fair skies today with highs ranging from the upper 60s in
the higher elevations east to readings in the lower 70s south and
west. Winds will be breezy at times from the southwest at 7-14
mph.
Tonight.
The upper longwave trough will dive southeast into the Southern
Plains and Mid-South Regions overnight. The associated cold front
will push southeast into the northwest portion of the state later
tonight.
Expect some more clouds northwest overnight, but increasing
southerly flow in the lower levels will allow low-level moisture
in gradually increase with time. Patchy fog is forecast to develop
through the early morning hours and persist through mid morning
across the southern third of the forecast area and across the
east-central portions of the area. Lows will range from the upper
40s northeast to the lower 40s elsewhere. Winds will be from the
south 3-6 mph.
Saturday.
The longwave trough will move into the region during the day
Saturday as the cold front pushes through the forecast area.
Expansive surface high pressure extending from Southern Canada
down into Texas will build into the region from the northwest
through the day.
Clouds will continue to increase through the morning hours with
isolated showers generally along and northwest of the Interstate
59 corridor. Highs will range from the upper 40s northwest to the
lower 70s southeast. Winds will shift from the south to the
northwest 6-12 mph through the day.
05
.LONG TERM...
/Updated at 0223 PM CST Fri Feb 11 2022/
Model trends continue to show weaker forcing and less moisture as
the mid level trough moves through the area. The chance of light
rain or snow showers quickly diminishes Saturday evening, and will
not carry measurable pops or weather beyond 00Z. Won`t rule out a
sprinkle or flurry, but chances are very low.
A cold airmass will settle over the area to begin the week, but
quickly moderates ahead of the next frontal system, impacting the
area Thursday. Too early for any more details than what is
mentioned in the previous discussion, and will continue to
highlight the possibility of tornadoes in the HWO.
14
Previous long-term discussion:
/Updated at 0337 AM CST Fri Feb 11 2022/
Saturday night through Thursday.
Western ridge/eastern trough pattern remains in place for the
weekend. A shortwave moves through the area Saturday night,
eventually phasing with the subtropical jet once it passes the
area, while an associated strong cold front moves through. Models
seem to be coming into agreement on the shortwave remaining
positively tilted with weaker 850-700mb frontogenesis. Did
consider removing PoPs altogether Saturday night, but with some
high res guidance including the HRRR and HiResW-FV3 still
indicating light precipitation as well as some GEFS members, and
given decent 850-700mb mean RH values, will maintain the slight
chance of rain/snow for the area and continue to monitor. A
clipper system then moves in on Sunday. At this time it remains
moisture starved, but it will bring a secondary cold front keeping
temperatures below normal Sunday and Sunday night. Winds begin to
shift to the west on Monday with temperatures still running a
little below normal.
A pattern flip occurs next week as the West Coast ridge is
replaced by a trough, and a ridge strengthens over the western
Caribbean up into the Bahamas. Have continued to incorporate the
warmer NBM percentiles for highs beginning on Tuesday. The
synoptic pattern for Thursday checks a lot of boxes for severe
weather across the Deep South and Mid-South with a low amplitude
southern stream trough and deepening surface low lifting
northeastward across the Ozarks, with an associated mid-level
speed max on the shortwave`s southeast flank. A strong 60 to 70 kt
LLJ will also bring 65F dew points northward. I suspect models
are underdoing the forecast CAPE values in this setup. This system
is several days out and there is some uncertainty regarding how
the southern stream trough interacts with the northern stream
along with an upstream wave, but will introduce a low confidence
tornado mention into the HWO.
32/Davis
&&
.AVIATION...
00Z TAF Discussion.
A cold front moves into the area Saturday. Light and variable
winds are anticipated overnight and become northwest by afternoon
around 10kts. A few gusts are also possible. The restrictions come
in the form of fog and low clouds possible early Saturday. Warm
advection of very near surface moisture will take place after
06z. How widespread and what terminals are affect remain the
questions at hand. Will start off will tempo IFR vis/ceilings at
MGM and vis at TOI. It appears the next in line would be TCL/EET.
This will be relatively short-lived and gone by 15z.
75
&&
.FIRE WEATHER...
Dry weather will persist through the weekend, with only a low
chance of a shower in the extreme northwest Saturday afternoon.
Moisture does increase ahead of a cold front, with minimum RH
values in the 35 to 50 percent range tomorrow afternoon. Ceiling
heights should remain above 2kft. Low RH values (20-30%) return
Sunday through Tuesday. Southwesterly 20ft winds become northerly
Saturday morning, increasing to 6-10mph through the day and remain
elevated Sunday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 38 58 24 46 21 / 0 0 10 0 0
Anniston 40 62 28 46 24 / 0 0 10 0 0
Birmingham 43 59 28 46 25 / 0 10 10 0 0
Tuscaloosa 41 61 28 49 26 / 0 10 10 0 0
Calera 41 62 30 48 28 / 0 0 10 0 0
Auburn 41 67 34 49 28 / 0 0 10 10 0
Montgomery 41 67 34 53 28 / 0 0 10 0 0
Troy 42 73 35 52 29 / 0 0 10 10 0
&&
.BMX WATCHES/WARNINGS/ADVISORIES/...
None.
&&
$$
Area Forecast Discussion
National Weather Service Cleveland OH
926 PM EST Fri Feb 11 2022
.SYNOPSIS...
Low pressure will move across eastern Ontario tonight dragging a
strong cold front through the region. High pressure will attempt
to build into the Ohio Valley late Saturday, but a series of
troughs will drop across the region through the weekend. High
pressure will more firmly move in early next week before moving
east and allowing a warm front to lift through by Wednesday.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
Rain showers are beginning to exit east of the area this evening
as colder air begins to filter in behind the first cold front. A
secondary, reinforcing cold front will arrive later tonight into
tomorrow morning, introducing the next chance for snow showers,
especially across NE OH and NW PA.
Previous Discussion...
Latest surface and RAP analysis has the cold front still over
western Ohio, but it appears to be east of TOL and moving into FDY.
This front is tied to a significant mid/upper shortwave trough
digging into the Upper Midwest and western Great Lakes with an
associated 996 mb surface low passing north of Lake Huron. Strong
upper divergence from the right entrance of a 100-110 knot H3 jet
progressing out of lower Michigan is leading to a 45 to 50 knot
southwesterly low-level jet. Some mixing of this LLJ combined with a
tightening surface pressure gradient and downsloping near the
lakeshore is leading to SSW winds gusting to 30-40 knots at a few
sites, namely Burke Lakefront Airport and Fairport Harbor
Lighthouse. Inland areas are seeing gusts mainly in the 25-30 knot
range, so did not issue an advisory given the fairly isolated
coverage of the higher gusts. Widespread showers associated with the
aforementioned upper divergence and strengthening frontogenetic
forcing have now spreading across the entire area, so expect a wet
evening commute.
The deep surface low will lift through eastern Ontario early tonight
dragging the cold front across the rest of the CWA this evening. The
steadiest rain will be confined to the Ohio/PA line by 02Z exiting
the rest of the area by 04Z. This front is more of a wind shift and
moisture gradient since upstream observations are not showing a rapid
drop in temps behind it. There will be enough post frontal cold
advection to change lingering light precip to light snow showers
before tapering off. Winds behind the front this evening will
quickly diminish to 10-20 knots while veering WSW except for 20-25
knots lingering near the lakeshore the first half of the night. A
punch of drier mid-level air behind the front should lead to a
period of mainly dry conditions in the 04 to 08Z timeframe before
snow showers increase ahead of a secondary cold front/surface
trough. This trough will bring in the true arctic air. NAM and RAP
BUFKIT soundings immediately ahead of the trough suggest a notable
increase in low and mid-level moisture in the 08-12Z timeframe with
850 mb temps falling to -13 to -15C by 12Z and inversion levels
rising to 7-8 thousand feet. This will set up a lake response as
lake induced CAPE builds to a conditional couple hundred joules with
winds veering to westerly and a period of lift in the DGZ coincident
with the trough passage. Blended in higher PoPs from about 08Z
through mid morning, especially from Lorain County east through the
primary snowbelt of NE Ohio and NW PA. HREF members suggest that the
aforementioned parameters plus south shore convergence as the trough
passes will push a burst of snow through these areas putting down a
quick few tenths to inch and a half. The accumulating snow will
however not last long because moisture depth and inversion levels
are expected to quickly tank Saturday afternoon with a loss of
Omega, as well as increasing boundary layer shear as weak shortwave
ridging attempts to build in ahead of the next mid/upper shortwave
trough. This will lead to a rapid decrease in coverage and
organization of any snow bands Saturday afternoon, but still kept
PoPs fairly high for scattered light snow showers and flurries in
both the primary and secondary snowbelts through evening given 850
mb temps continuing to cool to -15 to -20 C and continued WNW flow
off the lake. Lots of water has opened up the past several
days, so believe forecast soundings are probably underestimating
the amount of latent heat flux despite the lowering inversion.
Clouds will remain widespread Saturday night as the next
shortwave drops into the western Great Lakes. Increasing mid-
level moisture and upper forcing will spread light snow across
Lake Erie into the northern tier of counties, so brought back
PoPs after 10Z.
Lows tonight will fall into the low/mid 20s with not much rise on
Saturday given strong cold air advection. Saturday night will be
very cold with lows dipping into the single digits and low teens.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A clipper will move across the region Sunday into Sunday evening.
Moisture and lift are limited enough that a broad synoptic shield of
snow is unlikely. However, models remain in agreement in showing PVA
ahead of a potent vort max that will move west to east across the
region Sunday afternoon and evening to go along with an increase in
low to mid-level moisture. Guidance shows a subtle low to mid-level
trough axis crossing the region during the afternoon and evening as
well. Forecast soundings show steep low-level lapse rates developing
across the entire region during the day Sunday, including through a
dendritic growth zone (DGZ) that will be located 2-4k feet above the
ground thanks to the cold airmass in place. Given what looks like
sufficient saturation in and above the DGZ to go along with the
various sources for lift, feel that much of the area will at least
see some flurries and scattered snow showers Sunday afternoon and
evening. Continued to carry slight chance to chance POPs area-wide
for this...suspect POPs will need to go up as we get closer and that
much of the area, even outside of the snowbelt, can see a dusting of
snow Sunday afternoon or evening. With steep low-level lapse rates
through the DGZ, some snow showers could have a bit of intensity.
With highs struggling to near 20 on Sunday and temperatures dropping
into the single digits for most areas Sunday night, even a light
amount of snow could stick to roads and cause slick conditions, with
a higher traffic volume than a normal Sunday evening expected given
a certain nationally televised sporting event that will be taking
place.
Believe that today`s runs of the regional Canadian model (RGEM) and
European are doing the best job of showing the rough mesoscale set-
up Sunday into Sunday night, which becomes important when trying to
pin-down lake effect potential not only off of Lake Erie but also
off of Lake Michigan towards the Toledo area. Am expecting a broad
west to west-northwest flow across the region Sunday into Sunday
evening, turning more northwesterly later Sunday evening, and then
backing more westerly late Sunday night into Monday morning. The
RGEM and Euro are both keying on a surface trough, connected to Lake
Michigan, working across extreme southern MI or far northwestern OH
towards western Lake Erie Sunday into Sunday evening. We often see a
trough develop here with that kind of flow. Believe the NAM`s idea
of taking this trough towards west-central OH is wrong due to what
appears to be a significant error in handling the heat/moisture flux
off of Lake Erie. Forecast soundings for Sunday afternoon and
evening in Toledo show a fairly deep layer of saturation and steep
lapse rates in the low-levels, and believe this trough may help
focus activity off of Lake Michigan into far northwestern OH on
Sunday. So, have some light snow accumulations in the grids here,
and some bursts of moderate to briefly heavy snow wouldn`t be
shocking. It`s possible this trough sets-up just north of the OH /
MI line on Sunday, but even if that`s the case it should sink south
into Sunday evening as the winds gain more of a northwesterly
component.
The Euro and RGEM show this same trough connecting to the southern
shore of Lake Erie Sunday afternoon through early Monday, and both
models have 0.10-0.20" of QPF in the Cleveland area as a response.
Given a decent chunk of open water both east of the islands and
along the central lakeshore, which will encourage modification of
the air over that part of the lake and upward motion, believe it
makes sense for this trough and convergence to focus in this area.
With the synoptic lift described above from the clipper system
moving through late Sunday into Sunday night, expect a fair amount
of lake enhancement to develop, focusing on where this surface
trough / convergence sets-up. With 850mb temperatures of -18 to -20C
and 700mb temperatures approaching -30C Sunday evening, there will
be moderate to nearly extreme instability over any open water with
inversion heights rising to 8-10k feet. These numbers further argue
for a robust lake response. As winds turn more northwesterly later
Sunday evening expect the trough to push inland, causing the lake
effect to move onshore and lose organization. Farther east, probably
enough moisture flux off the icy waters for at least some lake
enhancement into the rest of the primary northeast OH / northwest PA
snowbelt as the synoptic support maximizes Sunday evening. As winds
turn more westerly into Monday morning there may be another uptick
in snow showers along the eastern lakeshore into the northern
primary snowbelt, though overall conditions won`t be as favorable
for a robust lake response at that point, so expect activity by
Monday morning to be on the lighter side.
With all of this said, hit much of the lakeshore from Erie County,
OH points east into PA with likely POPs Sunday afternoon and
evening. Bring POPs / QPF inland a bit Sunday evening as the winds
turn more northwesterly, with POPs / light QPF then focusing up the
eastern shoreline by early Monday as the ridge approaches and winds
turn more westerly. Have 1 to locally 4" of snow in the grids from
eastern Erie County, OH points east through the snowbelt Sunday
afternoon through early Monday, but given what will be a fluffy snow
if any organized bands develop Sunday evening I don`t want to rule
out a locally higher amount. Given the light flow, expect greatest
snow accumulations to occur fairly close to the lakeshore overall.
The large area of open water east of the islands may help focus
accumulations as far west as Erie and Lorain Counties. Models may
struggle with this one given they`re initializing with an icy lake
and under-doing the flux off of it, so a tricky forecast with low
confidence, but potential is there for travel impacts near Lake Erie
Sunday afternoon and evening.
Aside from lingering lake effect near the eastern lakeshore Monday
morning, expect a cold but dry day. A clipper grazing the region to
the north may try scraping extreme northeast OH and northwest PA
with snow showers Monday night, but the rest of the area looks dry
with any snow with this system in the far northeast minimal.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
High pressure in control Tuesday and Wednesday with a return flow
developing and moderating temperatures expected. Next item of
interest is a wave of low pressure that will develop over the
southern Plains on Wednesday and track towards the area Thursday
into Thursday night, departing on Friday. For now am still expecting
mainly or all rain through Thursday, though models have trended
farther southeast with the track of this low so can`t rule out some
areas (especially northwestern Ohio and points east near Lake Erie)
trying to flip to snow Thursday or Thursday night as the low moves
by and colder air starts to return. While we`ll monitor the track of
the low for potential wintry implications, still feel most of the
QPF is likely to fall as rain at this point and that an outcome
similar to last week`s winter storm is quite unlikely.
Of greater concern is flooding...decent confidence in 0.75-1.50" of
QPF with this whole package late Wednesday or Wednesday night
through Thursday night (which is when the bulk of precipitation
looks to occur), with a lower potential for 1.50-2.50" shown on
ensemble guidance. The snowpack holds an inch or less of water east
of I-77, but is estimated to hold 1-2" of water to the east, with
locally over 3" in the snowbelt in northeast OH / PA. Some gradual
melting has occurred this week and a bit more will occur early next
week, with the potential for a more rapid melt Wednesday and
Thursday. It`s possible all of the water in the snow doesn`t get
released at once, but still enough meltwater likely getting released
that some flooding concerns will exist the second half of next week.
Questions about whether or not we get higher-end QPF, along with
questions about how quickly the water in the snow pack gets
released, precludes confidence in a significant flood threat for
now, but feel that at least some minor flooding on some area rivers
will be hard to avoid unless we trend towards a much colder system
or towards much less QPF. Will also need to monitor frozen rivers
for ice jam issues as temperatures moderate next week. Greatest
overall concern for flooding will be where snowpack is greatest in
eastern OH and into PA. Plenty of time to iron out details, but if
you are in an area prone to river flooding be sure to check back on
this situation as we head into next week and gain confidence in any
details.
Temperatures approach normal on Tuesday, with highs in the 40s and
50s for Wednesday and Thursday. Temperatures return towards more
seasonable values into Friday as colder air moves in behind the low
pressure.
&&
.AVIATION /00Z Saturday THROUGH Wednesday/...
Generally MVFR conditions exist across the TAF sites this
evening with a few, brief pockets of VFR possible over the next
several hours into the first half of tonight. Light rain showers
have been observed across some of the eastern TAF sites, though
no vsby restrictions have been noted at this time. Any IFR
ceilings should not last more than an hour or two. MVFR
conditions are expected to persist through much of the TAF
period, generally associated with lower ceilings. The best
chance for any IFR conditions would be at ERI late tonight into
Saturday morning from reduced vsbys in snow showers. Scattered
snow showers may also impact CLE/CAK/YNG and will need to be
monitored for any adjustments to IFR vsbys. VFR may begin to
appear towards the end of the TAF period across the western TAF
sites.
Southwest winds continue to be gusty this evening, 20 to 30
knots. Isolated pockets of 30 to 35 knots have also been
observed ahead of the rain. Southwest winds will begin to
decrease into the 10 to 15 knot range later tonight, becoming
more westerly by Wednesday morning. West to northwest winds of
10 to 15 knots will then persist through Wednesday.
Outlook...Non-VFR possible in snow showers Saturday into
Sunday. Non-VFR may persist Sunday night into Monday across NE
OH and NW PA.
&&
.MARINE...
Gusty southerly winds will turn more northwesterly into Saturday
morning and then subside over the weekend. Southerly winds will
increase Wednesday and Thursday of next week, turning more northerly
into Friday. Expect some ice growth over the nearshore waters this
weekend, though the milder weather and southerly winds next week
will cause renewed movement of the ice away from the southern shore.
As has already been said over the last week, the ice on Lake Erie
will not be a safe place to be anytime soon and it`s strongly
advised to stay off of it.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Garuckas
NEAR TERM...Garuckas/Kahn
SHORT TERM...Sullivan
LONG TERM...Sullivan
AVIATION...Kahn
MARINE...Sullivan
Area Forecast Discussion
National Weather Service Flagstaff AZ
904 PM MST Fri Feb 11 2022
.SYNOPSIS... Tranquil and warm weather continues across Arizona
through Monday. Expect periods of gusty northeast winds through
Saturday, with lighter winds Sunday and increasing southwesterly
winds Monday and Tuesday. A more active pattern is possible for
the early to middle parts of next week.
&&
.UPDATE...Another quiet night is unfolding across northern Arizona
outside of gusty northeast winds along and south of the rim.
Expect gusty northeast winds to continue in these areas through
Saturday morning with lighter winds returning by the afternoon.
The current forecast handles this well with no updates needed this
evening.
&&
.PREV DISCUSSION /208 PM MST/... The upcoming weekend will be warm
with daytime high temperatures ranging between the 50s to near 80
degrees toward southern Yavapai County. We`ll need to contend with
some blustery overnight/early Saturday morning conditions,
particularly along the Mogollon Rim, the White, Black, and
Bradshaw Mountains thanks to a diffuse shortwave trough diving
southward through the Four Corners. While the RAP model is the
most aggressive with 50 knot 700mb flow Saturday morning,
experimental NBM probabilistic guidance appears to advertise
reasonable magnitudes for wind gusts (though I`ve tapered these
down) with peak gusts of around 35-40 knots through at least
midday Saturday at the higher elevations. With weaker northerly
flow and no indication of any additional shortwave troughs
rippling through the remainder of the weekend and into early next
week, we`ll be looking at largely fair weather across the High
Country.
Toward the middle of next week, confidence is high that a pattern
shift will transpire. There`s still some uncertainty regarding
the ultimate track of the upper low which will dictate
precipitation chances and amounts. What is for certain is that
high temperatures Wednesday through the end of the week will fall
10 to 15 degrees below normal and so it`ll feel like winter across
the area. Southwesterly winds will also increase with speeds
between 20 and 30 mph Tuesday and Wednesday. Gusts close to 45 mph
are expected.
It does appear that enough of the deterministic and probabilistic
model guidance has slowed the ejection of the main upper trough
as blended guidance has trended upward just a touch with
advertised PoPs. Standardized anomaly PWAT values return to near
normal levels and while I don`t anticipate a widespread
significant precipitation event, the official forecast PoPs have
increased from the last forecast iteration. This is especially
true for areas along the southwest aspects of the higher terrain.
PoPs generally range between 30 and 70 percent across the area
late Tuesday and into early Thursday.
From a kinematic standpoint, the upper trough is impressive in
just about all of the major deterministic NWP as 150 to 200 meter
height falls are progged to expand across Northern Arizona.
Southwesterly 500mb flow also strengthens to magnitudes in excess
of 50 knots late Tuesday and into Wednesday. While moisture
content for widespread precipitation isn`t ideal, it`s quite
possible that the orographic ascent may augment what would
otherwise be a largely underwhelming event. Given the enhanced
upslope flow, the greatest PoPs run from areas along the Rim
(including Flagstaff), back toward the southeast (just north of
Payson), and into the White Mountains. From a probabilistic
standpoint, there appears to be a good chance (60%) of seeing at
least an inch of snow across the aforementioned geographic zones
with a 60-70% chance of 2-3" of snow across the White Mountains.
The White Mountains and parts of the rim could be beneficiaries of
a second shortwave trough that slides southward early Thursday.
Again, any shift in the track of the upper lows could result in
changes to the PoP, QPF, and expected snow amounts, so check back
for updates to the forecast.
&&
.AVIATION...For the 06Z package...VFR conditions prevail through
the TAF period. North/northeast winds at 10-15 kts with gusts
20-25 kts will be possible over the high terrain. Winds should
calm after 00Z Saturday. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...
Warm and dry conditions are expected. Winds continue from the
north/northeast Saturday, especially along and south of the
Mogollon Rim, with light winds Sunday.
Monday through Wednesday...Continued warm and dry conditions are
expected Monday. Winds increase from the southwest Monday and
Tuesday ahead of an approaching system, with chances for
precipitation increasing late Tuesday. Precipitation moves from the
northwest towards the southeast through Wednesday with winds
shifting from the southwest to the west.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...ET/Bain
AVIATION...ET
FIRE WEATHER...Kobold
For Northern Arizona weather information visit
weather.gov/flagstaff
Area Forecast Discussion
National Weather Service Goodland KS
850 PM MST Fri Feb 11 2022
.SHORT TERM...(This evening through Sunday)
Issued at 205 PM MST Fri Feb 11 2022
At the beginning of the short term period, current RAP analysis
shows the CWA having a northwesterly flow aloft being underneath the
back part of a trough. Radar data is showing some echoes moving from
the north into southwestern NE though current obs do not show
precipitation reaching the ground in the CWA or in the nearest
adjacent counties. Satellite imagery shows cloud coverage over most
of the CWA with high clouds moving eastward and lower clouds
traveling to the south-southeast. From the obs, winds are still
gusting up around 35 kts from the north-northwest. Due to these
winds and precipitation potential, brief snow squalls may be
possible lowering visibilities in the northern two rows of counties
in the CWA as this occurred with precipitation outside north of the
CWA this afternoon. Later Friday, models show the upper air flow
transitioning to north-northwesterly as the trough base moves just
south of the CWA. At the surface, chances for quick light snow
shower moves from north to south across the CWA along the leading
edge of a second burst of cold air moving into the CWA from the
north. Minimal accumulation looks to be expected should
precipitation. Overnight low temperatures on Friday look to be in
the middle teens with wind chills in the single digits.
On Saturday, model guidance shows the CWA underneath the back part
of the trough with a northerly to north-northwesterly flow aloft
throughout the day. At the surface, dry conditions are expected with
generally westerly winds as a surface low moves southeast through
the eastern portion of NE during the evening. Daytime highs on
Saturday look to be in the middle 40s while overnight lows range
from the upper teens to lower 20s.
For Sunday, the CWA has a northwesterly flow aloft as a ridge in the
western CONUS moves eastward throughout the day putting the CWA
underneath the front part of the ridge. At the surface, the CWA
continues to see dry conditions with possible elevated fire weather
conditions along and west of the CO border with minimum RH values in
the upper teens. Winds may come close to reaching criteria in these
areas with gusts exceeding 20 kts during the afternoon may be
possible. This situation will be monitored to see if conditions
change. Daytime highs for Sunday expect to be in the upper 40s to
upper 50s followed by overnight lows in the lower to upper 20s range.
.LONG TERM...(Monday through Friday)
Issued at 146 PM MST Fri Feb 11 2022
In the extended... Period will begin with low amplitude ridging in
place across the CWA with main concern being several cold frontal
passages intruding on the area. While there may be a window between
the cold fronts where fire weather could be a concern due to
intensifying winds, confidence with respect to the timing of each
feature remains very low. Low confidence continues into the later
half of the week as the next storm system takes aim at the southern
plains. Operational models and their ensemble clusters seem to be in
two general camps, a progressive open wave or a closed, slower and
more intense system. While the second scenario would definitely
give the region the potential for heavy snow, strong winds and
numerous other impacts, hard at this point to say that is a
favored or even most likely solution. Given the large amount of
uncertainty present in the upcoming system, I think it is
reasonable to say there is a good chance for accumulating snow in
the Wednesday night to Friday morning time frame. For those with
travel our outdoor interests, please stay aware of the latest
forecast for this time period as details become clearer.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 850 PM MST Fri Feb 11 2022
KGLD...VFR conditions are currently expected through the period. A
north wind around 10kts at taf issuance will gradually back to the
northwest at similar speeds around 10z then to the west-northwest
around 13kts at 16z. Occasional northwest winds gusting up to
25kts or so are expected from 18z-20z. From 21z-04z a west wind
around 10kts is expected, veering to the west-northwest around
12kts at 05z. Streamers of low clouds and sub VFR conditions are
possible from taf issuance through about 10z as they move from
northwest to southeast across parts of the forecast area.
KMCK...VFR conditions are expected through the period. A northwest
wind up to 10kts at taf issuance will back to the west around 6kts
by 11z and continue through 16z. From 17z-21z west winds
occasionally gusting up to 25kts or so are expected. From 22z
through the rest of the period, winds slowly veer to the northwest
around 10kts.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...076
LONG TERM...JRM
AVIATION...99
Area Forecast Discussion
National Weather Service Gray ME
950 PM EST Fri Feb 11 2022
.SYNOPSIS...
A cold front will approach the area from the west tonight before
crossing the region on Saturday. This will bring a few rain and snow
showers late tonight and on Saturday morning. Temperatures will
climb well above normal again on Saturday before much colder air
returns behind the front Saturday night. High pressure will
build in for the first half of next week with temperatures below
normal as a coastal storm misses the region to the south and
east. Temperatures moderate by the second half of next week.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
0245Z Update...
Latest update was to once again adjust hourly temperatures as
some areas have decoupled while most others have not. A southern
wind has increased in response to a strengthening jet aloft,
allowing more areas to climb through the 40s this evening.
Radar continues to indicate echoes across mainly northern
portions of the forecast area. Latest observations and most
webcams across the region only showing some flurry activity
across the higher terrain of the north. This appears to be
realistic based on 00Z GYX sounding which indicates dry air in
the lower and middle portions of the atmosphere, up to around
600 mb. Nevertheless, as moisture continues to advect into the
region, scattered snow showers can be expected over the higher
terrain with light accumulations above 2000 feet. For the rest
of the region, light rain showers may gradually spread mainly
towards central portions of the forecast area by later tonight.
Update...
Temperatures continue to fall very slowly this
evening as warm air advection increases over the forecast area.
Temperatures will follow with remaining steady or slowing rising
during the overnight hours as a low level jet develops over the
region. Mid level moisture will continue to advect into the
region this evening per latest surface observations and HREF
solution.
Echoes continue to mostly remain over northern New York State
and Vermont this evening. As low pressure rides east through
Canada, precipitation will mainly be confined to far northern
portions of the forecast area. This is supported by the latest
HRRR and 3 km Nam solutions.
Prev Disc...
High Impact Weather Potential: Minimal.
Pattern: Early afternoon water vapor imagery shows an amplifying
trough over the Great Lakes region with a longwave ridge just off
the west coast of North America. Associated with the trough is an
area of surface low pressure centered over the upper peninsula
of Michigan which is gradually moving north and east. This
places northern New England in the warm sector south and east of
the surface low with ongoing warm advection allowing spring-
like temperatures to flow into the area. For the near term
forecast period...the aforementioned surface low will move well
north of the region...with a surface cold front reaching the
eastern Great Lakes by daybreak Saturday. Thus...the primary
forecast focus will be on any shower potential as the front
nears from the west...and surface temperatures as these showers
arrive.
Through this evening...High clouds will continue to increase as the
shortwave trough to our west slowly approaches. Temperatures won/t
fall very far...remaining in the upper 30s and lower 40s south of
the mountains by 7pm with readings falling back into the lower/mid
30s to the north.
Tonight...Low pressure over the Ontario/Quebec border this evening
marches north and east overnight with top down saturation occurring
across our area ahead of the upstream shortwave trough. Moisture
deepens with PWATs pushing above 0.5" but best +DPVA brushes
our northern zones with westerly component of the flow favoring
little in the way of precipitation south of the mountains with
weak downslope component. Thus...will paint highest PoPs in the
mountains /chance to low likely/...chance in the foothills...and
slight chance to the south and east. Temperatures will be
marginal for rain and snow up north with a few sprinkles the
most likely Ptype south of the mountains. It will be a mild
night with strengthening gradient keeping the area coupled with
an impressive LLJ just off the deck /50-55kt at H9/. Thus...
expect temperatures to fall little after this evening...
remaining in the lower/middle 30s of the mountains...and the
upper 30s to lower 40s to the south. Any precipitation will be
light /generally less than 0.1"/.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
High Impact Weather Potential: Minimal.
Pattern: A surface cold front passes through the region on Saturday
and then offshore Saturday night. Our first focus is therefore on
shower potential with the front as well as temperatures ahead of the
frontal passage. Cold advection will continue Saturday night with
the focus shifting to colder temperatures.
Saturday: Surface cold front arrives from the west...crossing
the CWA in the afternoon. 0.5-0.7 inch PWAT plume overhead in
the morning will fold east before cold/dry advection ensue. Best
shower chances...therefore...will be in the morning with
activity increasingly becoming confined to the upslope areas in
the mountains as the deeper moisture heads east. The timing of
the front indicates that we/ll sneak in one more mild day as T9s
ahead of the boundary push towards +5C across southern areas
and +2-3C in the north. This would support mid 50s under full
mixing and though there will be some cloudiness...only went
below the fully mixed values a tad given what should be good
mechanical mixing and some glimpses of sun. Thus...lower 50s
should be widespread south of the lakes region in NH and far
southwestern ME with 40s elsewhere.
Saturday Night: Cold/dry air advection continues under westerly
flow with remaining mountain snow showers coming to and end and
a partly/mostly clear night expected. CAA will drive lows back
towards zero along the international border with teens and 20s
for areas to the south and east. The guidance consensus has this
idea well covered and was followed in the forecast.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
Long-range models continue to show disruptions to the +PNA
pattern at 500 MB that settled in for much of the the 2nd half
of January, as blocking over the E Pacific breaks down and
allows waves to move onshore into W NOAM. It`s not a complete
breakdown, but it is likely to put us back into a more
changeable pattern with alternating warm and cold spells through
next week and into next weekend. Only threat for more signify
precip will be toward the end of next week, but this looks like
it will be warm enough that p-type will be mostly rain, perhaps
even into the mtns, although at this time range confidence on
p-types is still low.
Sunday we`ll see southern stream energy move out of the gulf states
toward the Grand Banks, while lagging nrn stream trough moves across
the area Sunday night. This will mostly be a miss as far as precip
goes although interaction between these systems could produce
some light snow on the NW side of the storm which may bring a
short period of light snow or snow showers mainly to areas near
or just inland of the coast. Highs Sunday will be in the 20s to
around 30.
Behind this system the core of the coldest air will move in for
Monday. when highs will be in the teens to around 20, despite mainly
sunny skies. Mon night lows will drop to around -10 in the mtns and
generally -5 to +5 in the south. Sfc high passes over Tuesday and
Wed and Tue will be warmer than Monday but still below normal with
highs in the 15-10 in the mtns and 25-30 in the south. As the sfc
high shifts offshore Wednesday, return flow should allow temps
to jump up by 5-10 degrees on Wed with highs mostly in the 30s.
500 MB ridging builds in for Thu as 500 mb low closes off over the
srn plains, but also stretches out to the NE. This will allow
fairly decent mid-lvl baroclinic zone to develop just to our N. This
puts us on the warm side, and could see highs reach into the 50s in
many spots of Thursday, but it comes with a lot of clouds and
rain showers. Models then develop series of weak sfc lows along
this boundary, which will bring steadier precip into the region
Thu night and Fri, and again this will be mostly rain, but may
see lowering snow levels in the mtns on Friday. Still a lot of
time between now and then, so plenty of time for models changes.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Short Term...
Summary: A cold front will approach the region tonight...passing
through the area on Saturday. This will bring some lowering clouds
and some potential for a few showers.
Restrictions: VFR conditions will largely dominate the TAF period.
Ceilings will lower late tonight through much of the day on Saturday
with the greatest threat for restrictions being in the mountains
/HIE/ where a rain shower is possible.
Winds: Southerly winds around 10kts will diminish to 5-10kts
tonight before strengthening from the southwest and west on Saturday
12g18kts before veering northwest around 10kts for Saturday night.
LLWS: Southwest winds at 1.5kft increase to 45kt tonight with LLWS
for the overnight period throughout the area.
Long Term...Some MVFR possible in low cigs and light SN at
coastal terminals Sunday, but otherwise VFR expected Sun night
through Wednesday.
&&
.MARINE...
Short Term...Have included all of the waters in SCAs for tonight
based on latest observations and forecast conditions.
Long Term...SCAs will likely be needed late Sunday into Sunday
night in NW flow, and then again on Wed in SW flow.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 7 PM EST Saturday for ANZ150>154.
&&
$$
NEAR/SHORT TERM...Cannon
LONG TERM...Cempa
Area Forecast Discussion
National Weather Service Louisville KY
940 PM EST Fri Feb 11 2022
.Forecast Update...
Issued at 935 PM EST Fri Feb 11 2022
Double-barrel fropa is underway as the first cold front has pushed
southeast through most of central Kentucky and is now just NW of the
Lake Cumberland region, while the secondary boundary is just south
of Interstate 70 across Illinois and Indiana. In between a band of
light rain has been left behind, and is moving more slowly than
previously advertised. Will bump POPs for the next couple of hours
near and just south of the Ohio River, but there is a notable
weakening trend to our west as this precip tries to push through.
Should just be a chilly rain with amounts around a tenth of an inch,
if that. As we get deeper into the night, still expect to come into
line with the going forecast. Updates on the way shortly.
Issued at 600 PM EST Fri Feb 11 2022
Winds are gradually diminishing across central Kentucky, with only a
few spots along and just north of the I-64 corridor still touching
Advisory thresholds. With the cold front now dropping through
southern Indiana, and the sun setting, would not expect that to last
long enough to merit extending the Wind Advisory, so will let that
headline expire on schedule at 23Z. Minor tweaks to the timing of
the band of light rain that will accompany the cold front, but
otherwise the previous forecast is fairly well on track.
&&
.Short Term...(This evening through Saturday)
Issued at 254 PM EST Fri Feb 11 2022
Winds have gusted into the 40-50mph range this afternoon, but those
gusts will be dropping off quickly late this afternoon as cloud
cover increases and the sun sets. We have flirted with higher fire
danger in our southeast (Lake Cumberland/southern Blue Grass) but so
far fuel moisture has remained just high enough for most of the day
and most areas have experienced generally high enough humidity to
preclude needing a Red Flag Warning. RH and fuel moisture are lower
over eastern Kentucky.
A cold front stretching from Michigan to Texas will push southeast
through the Ohio Valley this evening accompanied by a band of light
rain and precipitation amounts less than a quarter of an inch. Can`t
rule out a few snowflakes as the precipitation ends late tonight but
no impact is expected. Morning lows will range from the mid 20s in
southern Indiana to the mid 30s around Lake Cumberland. Winds will
keep up around 10-15 mph and help to dry off any wet roads.
Saturday cold air advection will bring flow off the Great Lakes into
the middle and upper Ohio Valley, and we`ll be ahead of an
approaching upper trough axis. Moisture will be very limited under a
strong inversion. Will account for a small chance of isolated light
snow showers, which is supported by the HRRR and RAP, but most
locations will likely stay dry. The best chance for a snow shower
will be along and north of I-64. It will be a chilly day with winds
coming in from the northwest around 10-15 mph and afternoon highs
in the 30s.
.Long Term...(Saturday night through Friday)
Issued at 300 PM EST Fri Feb 11 2022
Synoptic...The long term forecast starts with broad cyclonic flow
aloft as a trough axis is oriented SW-NE from the Great Lakes
towards the Gulf Coastal Plains. Dropping from the Canadian Prairie
provinces, an upper-level low opens up at the same time it swings by
the upper Ohio Valley. The accompanying low pressure and cold front
are relatively weak, so no major changes are expected during the
weekend. Thereafter, surface high pressure and zonal westerlies
support a dry and cold spell for KY and IN. However, the mean wave
pattern will change by the middle of next week as the long-anchored
above-average heights over the Western US retreat to the Pacific and
an amplifying trough/closed low settles in. As a result, the
preferred corridor of frontal waves will be located from the
Southwest US to the Great Lakes, opening the possibility of heavy
rain and thunderstorms in the Ohio Valley.
Saturday night-Sunday...Arctic post-frontal airmass lowers temps to
the upper teens on Sunday morning. Despite some sunshine during the
first half of the day, the aforementioned cold front will slightly
increase precipitation chances in the afternoon and early evening.
Below-freezing thermal profiles along the vertical and saturation in
the lowest layers (including the DGZ) support snow as this system`s
precipitation type. Nonetheless, the limited moisture and DGZ depth
combined with the weak mesoscale lifting should only account for
uneventful snowfall rates. Highs at the end of the weekend should
stay at or near the 32 degrees mark.
Monday-Wednesday...Surface high pressure and strong mid-level
subsidence will impose blue-sky days by the start of next week. Lows
on Monday and Tuesday will stay below freezing, although Monday will
be the coldest of the two. There is a notable warming trend between
highs on Monday (around 40) and Tuesday (low 50s) due to the wind
shifting to a southerly direction. As a shortwave trough and
attendant surface low approach from the southern Great Plains, the
pressure gradient will tighten and winds will speed up on Wednesday.
This resultant WAA will take afternoon temperatures to the low 60s
while dewpoints reach the low 40s. Overall, Wednesday should stay
dry with increasing high-level clouds.
Thursday-Friday...This period is the main focus of the 7-day
forecast due to the growing possibility of impactful weather. Models
are indicating a phasing between the northern and southern streams.
The interaction will take place along a baroclinic wave draped NE-SW
across the Mississippi and Ohio Valleys. But as it is characteristic
with a forecast this far out, models are struggling with timing and
most importantly strength of the northern stream (as highlighted by
the 500-hpa EOF guidance). There are two main scenarios to consider:
weak vs strong northern trough. If the trough is weaker than
expected, then the lower Ohio Valley will maximize the residence
time in the warm sector of the upcoming storm system. On the other
hand, a stronger trough will push the storm system southward so that
the heavy rain axis will fall near southern Indiana and northern
Kentucky. Regardless of the main output, anticipate rain and
possible thunderstorms to manifest in the second half of next week
as the main ingredients for convection will be present.
&&
.Aviation...(00Z TAF Issuance)
Issued at 605 PM EST Fri Feb 11 2022
Cold front came through HNB within the last hour with a quick wind
shift to NW and light rain, but no restrictions to cig/vis. Ahead
of the front we have gusty west winds touching 25 kt at times at SDF
and LEX. Expect the same wind shift to push through by mid-evening,
with sustained speeds dropping to 10-15 kt and diminishing gusts.
Precip type along the front shouldn`t be a problem as it`s just a
couple hours of light rain without vis restrictions.
However, behind the front a decent stratus shield will build down
into MVFR after midnight, but cigs should remain above 2000 feet.
NW winds will maintain a steady 10-12 kt for most of the period as
diurnal mixing will be cancelled out by the weakening of the CAA
surge. Could see a few flurries or snow showers, but not confident
enough to include anything more than VCSH and not expecting any
further restrictions to ceiling or vis.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...RAS
Short Term...13
Long Term...ALL
Aviation...RAS
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
923 PM CST Fri Feb 11 2022
.UPDATE...
Issued at 920 PM CST Fri Feb 11 2022
This evening`s scattered snow showers have mostly shifted east
over Lake Michigan with some lingering isolated light snow showers
and flurries across portions of northeast Illinois. We have also
had a few reports of some very light freezing drizzle/mist at
times. Flurries will likely linger across the area for the next
few hours.
A secondary boundary, mentioned in the afternoon short term
discussion below, is currently making its way south across Lake
Michigan. There remains some uncertainty with whether this feature
will still add to the longevity of snow shower chances into Cook
County. For now, opted to maintain the ongoing forecast for a
chance of snow showers lingering a couple hours past midnight
into Cook county and the immediate shoreline, with higher chances
into northwest Indiana.
No changes were made to the lake effect snow forecast into
northwest Indiana and more specifically northeastern Porter County
through Saturday morning, with 1-3" still possible. Will note
that the better chances still appear to be just east of our
forecast area into LaPorte County.
Lastly, given the quickly dropping surface temperatures below
freezing this evening after a warm day with plenty of snow melt,
any lingering puddles could freeze over, resulting in patchy
slick spots on untreated roadways and sidewalks. Do think that the
gusty winds should have helped dry out most roadways to prevent
it from being a widespread issue, but something to be aware of.
Petr
&&
.SHORT TERM...
Issued at 325 PM CST Fri Feb 11 2022
Through Saturday night...
The main concerns in the short term center on tonight, with
blustery conditions settling in behind a strong cold front. Snow
showers will also be seen in parts of the area, mainly northeast
Illinois and northwest Indiana, and some of these will probably
provide an isolated coating and sharply reduced visibility,
including the latter part of the commute in the northern suburbs.
Finally, lake effect snow in far northwest Indiana overnight into
Saturday morning looks to result in accumulating snow, possibly
up to 3 inches, for Porter County.
The advertised strong cold front is sweeping eastward through the
area as of 3 PM. West-northwest winds immediately behind the
front are gusting 35 to 40 mph in north central Illinois. These
winds are advecting in colder air quickly with Sterling, IL down
8F in just an hour, for instance. Temperatures are already in the
mid teens in northern Iowa and this will advect in here through
the night, aided by surface pressure rises on the order of 10-12
mb over just six hours this evening. Wind chills will be in the 0
to -5 range for much of the area by daybreak Saturday.
Along the front itself are developing isolated rain showers from
the Chicago metro down I-57. These not only have a convective
look on radar but also appearance visually, as out the window it
resembled more of a late spring day! These showers should largely
remain rain, though could have some graupel as they gradually
increase in coverage into northwest Indiana after 4 PM. The main
attention though is on the batch of snow showers in Wisconsin
associated with the low level front and frontogenesis along it,
as well as strong upper forcing and PVA above. This forcing, in
tandem with steepening low-level lapse rates within cold air
advection, should steer this into northern Illinois at least
along/north of I-88 through mid-evening. Confidence diminishes on
how far south this will spread, although any heavier snow showers
would be more favored in the northern locations. Upstream
reflectivity and visibilities indicate there are some sub 1 SM,
and would not be surprised if briefly under 1/2SM given the
concurrent winds and snow. This will likely overlap the latter
part of the evening commute in northern portions of the Chicago
metro. With accumulations likely to be streaky, and the mild
pavement going into this at first, feel that Graphical NOWcasts
and other more tactical messaging will address this.
Lake effect snow will take over as the more dominant driving
method of snow by overnight into northwest Indiana. Prior to that,
during the late evening, there is some indication of a secondary
trough/wind shift moving down the lake with some enhanced QPF on
the HRRR runs. This could provide a pretty good burst of snow
accompanied with a re-uptick in the winds, and may even graze the
Cook County shore. Evening shift will have to keep an eye on
mesoscale trends for this as its tough to say if that will
materialize at this point. Into the overnight, multicell lake
effect showers are expected into Porter and possibly Lake County
in northwest Indiana. Lake-enhanced equilibrium levels will rise
up to around 7,000 ft and with the cooling profiles the dendritic
growth zone is better intersected. This should continue into
Saturday morning, gradually waning late morning into the early
afternoon. Accumulations of 1 to 3 inches are forecast for
northern and eastern Lake County, but as always with lake effect
some variability is expected. Higher amounts, as well as
temporary convergence signatures, are better seen in high-
resolution guidance signatures further east. Some snow covered
roads can be expected through in parts of Porter County to start
Saturday.
Otherwise on Saturday, northern Illinois should see some breaks of
sunshine to offset an otherwise cold day. The 850 mb temperatures
are forecast -17C to -20C, and if we had fresh snow cover it would
be notably colder. Have highs only 18 to 22 across the area.
MTF
&&
.LONG TERM...
Issued at 232 PM CST Fri Feb 11 2022
Saturday Night through Friday...
Forecast concerns include two weak clipper systems, the first
Sunday morning, the second Monday morning and then a large storm
system to affect the region the middle of next week with the
potential for heavy rain, accumulating snow and possibly a wintry
mix.
A ridge of high pressure will move across the area Saturday
evening as a fast moving clipper system moves from the Dakotas
Saturday evening to southern IL by midday Sunday. A narrow band
of light snow is expected northeast of the track of this system
and currently appears to move across central IL, possibly
including the southern half or so of the cwa. Moisture is somewhat
limited and the fast movement will limit duration of the light
snow but a few tenths of an inch are possible. Blended pops
continue to be dry for this time period and continued low chance
pops. Even if there isn`t a swath of minor accumulation, flurries
will be possible across much of the area. As this system departs
early Sunday afternoon, there will be the potential for some lake
effect snow showers into far northwest IN. Confidence is fairly
low for how long these may persist but did include low chance pops
into Sunday evening.
Another ridge of high pressure will cross the area Sunday evening
and another fast moving clipper will move across the area around
or just before daybreak Monday morning. Moisture is even less
impressive during this time period but opted to carry low chance
pops across the northern half or so of the cwa for this potential.
Similar to Sunday morning, its possible that only flurries will
materialize.
Each of the two high pressures noted above will bring the
potential for a sharp drop in temps each evening and then temps
may level off as clouds spread in ahead of each system and only
medium confidence for lows each morning. The lighter winds should
keep wind chill values each morning near zero or higher. High
temps on Sunday will likely struggle to reach 20 degrees.
After the Monday morning clipper, dry weather is expected through
Wednesday morning with highs moderating into the lower 30s Monday
and mid/upper 30s Tuesday as southerly flow returns.
By Wednesday, low pressure will develop over the southwestern
Plains and is expected to lift northeast across northern or
central IL Thursday as it accelerates across the eastern Great
Lakes Thursday evening. Any precipitation on Wednesday appears to
be mainly in the afternoon, mainly rain and generally light, for
the daylight hours. Southerly winds may be gusting into the 30-35
mph range.
From Wednesday evening through Thursday evening, it remains too
early for specifics and small changes in the track of this storm
system will have large impacts on where accumulating snow may
develop, where any wintry mix may occur and where the heaviest
rains may develop. As an example, the 12z operational ECMWF has
jogged south slightly and changes like this can be expected for at
least the next few days.
As for items of concern, precipitable water values approach 1
inch, especially in the southern cwa, even higher further into
the warm sector. Storm total qpf from the models have been
consistently showing a swath of 1-2 inches, of rain. If this were
to materialize over parts of the area, there would be some
flooding potential, especially due to localized ice jams given
the current river ice coverage. As the colder air settles into the
northern side of the system, there will likely be a narrow
corridor of a wintry mix, including freezing rain. Unless there
were a significant shift north or south with this system, this
corridor of a wintry mix could possibly be right across the cwa.
And as the system finally departs, there will likely be a final
changeover to all snow and given the accelerating forward speed as
it departs, snow on the back side could be somewhat short in
duration. These are current concerns as the models show now.
Again, this time period is too far out for any specific yet. cms
&&
.AVIATION...
For the 00Z TAFs...
Aviation Forecast Concerns:
* Blustery west-northwest winds with sporadic 30+ kt gusts early
this evening.
* Period of convective snow showers this evening with brief IFR
visibilities and minor accumulations.
* MVFR ceilings prevail into Saturday, though gradually lift.
Strong surface cold front was pushing east across the area late
this afternoon, and was moving through the Chicago area terminals
as of 530 pm. Blustery west-northwest winds will shift more
northwest with time, and will be accompanied by sporadic 30-35+
kt gusts briefly this evening. A period of convective snow showers
behind the front will also bring brief periods of IFR visibilities
and some quick minor accumulations, though lowest conditions will
be be somewhat hit and miss due to their scattered nature. Snow
shower intensity should diminish later this evening, though
flurries and lighter snow showers persisting past midnight. KGYY
may see a little longer period of snow showers as lake effect
develops overnight, though the focus for heavier lake effect snow
showers should be largely east of KGYY especially toward morning.
Otherwise, MVFR ceilings will likely persist well into Saturday,
though with a gradual increase in cloud base heights above 2500
feet. Northwest winds will gradually diminish during the day,
eventually settling below 10 kts by Saturday evening.
Ratzer
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...Small Craft Advisory...IN nearshore waters until 9 PM Saturday.
Small Craft Advisory...IL nearshore waters until 3 PM Saturday.
&&
$$
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Area Forecast Discussion
National Weather Service Mobile AL
623 PM CST Fri Feb 11 2022
.UPDATE...Upon further review of model guidance for dense fog
tonight, decided to issue a Dense Fog Advisory for areas along
and west of the Alabama River (including Clarke and Baldwin
counties in AL). In addition, a Marine Dense Fog Advisory was
issued for Mississippi Sound and Mobile Bay. Both Advisories go
into effect at midnight tonight and continue through mid-morning
on Saturday. Take caution if traveling or boating tonight and
tomorrow morning! /26
&&
.AVIATION...
00Z issuance...VFR conditions were present at the TAF sites at
issuance and will continue at least for the first part of this
evening. Conditions will then begin to deteriorate late this
evening and into the overnight hours due to the development of
fog. Locations along and west of the Alabama River including the
Mississippi Sound and Mobile Bay will likely see dense fog
development by late tonight, with more patchy to areas of fog
anticipated over the Florida Panhandle and south-central Alabama.
In terms of the TAF sites, dense fog will therefore most likely
impact MOB and BFM, but not so much at PNS. Model guidance
indicates that this fog has the potential to linger into mid-
morning Saturday, so VFR conditions are not expected to return
until late morning to early afternoon. Light winds overnight will
increase to around 5-10 knots and shift to be northwesterly by
Saturday afternoon. /26
&&
.PREV DISCUSSION... /issued 438 PM CST Fri Feb 11 2022/
NEAR TERM UPDATE /Now Through Saturday/...The axis of the weak
shortwave trough moving east across the region today will be east of
the area by this evening. An area of light showers associated with
this feature over the Gulf is dissipating and will continue to move
off to the east. This area of precip mainly remained offshore. A
scattered to broken mid level cloud deck over the Gulf and the
southern half of the forecast area will be east of our area by this
evening.
A dry, zonal to southwest flow aloft returns tonight and continue
through Saturday in the wake of this feature. The deep layer dry
airmass will remain entrenched across our area through Saturday,
with precipitable water values ranging less than 0.6" across our
region. A somewhat variable light wind flow will continue across the
area as a weak surface ridge axis remains oriented along the north
central Gulf Coast. The next front will be approaching the
Mississippi Valley region by late Saturday, with clouds increasing,
but the still dry mid levels should inhibit any precipitation as the
front approaches. There is some return moisture at the very lowest
levels of the atmosphere though, and forecast soundings late tonight
indicate a very favorable profile for the development of patchy to
areas of fog over much of our region with the still very dry airmass
aloft over the saturated airmass right at the surface. Conditions
look favorable for possible areas of dense fog development late
tonight into early Saturday morning, but mid and upper level cloud
cover could be a hindrance. Later shifts will need to monitor trends
overnight for a potential Dense Fog Advisory issuance.
Not quite as chilly tonight, with lows mainly in the low to mid 40s
over inland (a few upper 30s possible in some normally colder
locations) areas and ranging from the mid 40s to near 50 degrees
along the immediate coast and beaches. High temperatures on Saturday
continue to look mild as the front approaches from the west, topping
out in the upper 60s to lower 70s at most locations (perhaps mid 60s
over northwestern zones which will be closest to the approaching
front). /12
SHORT TERM /Saturday night Through Monday night/...Overall the
short term should be dry for most of the area despite a
positively tilted trough moving across the area Saturday night
into Sunday morning. However, as prior shifts have noted there
could be a chance of a wintry mix to some light snow (flurries to
maybe light dusting) possible along and north of highway 84.
Upfront, this forecast seems very simple in that no precip will
occur as the main upper shortwave centered over the great lakes
and the southern stream shortwave are just not in phase with each
other leading to weak ascent in a rather dry regime.
Unfortunately, like many other forecasts before, it can never be
that easy. Majority of the guidance has trended towards the drier
solution with the out of phase troughs, then this afternoon the
18Z High-Res Rapid Refresh (HRRR) decides to spite all forecasters
around the area. Why you ask? Well, the 18Z HRRR is much quicker
with the southern stream shortwave and allows for a much better
phase between the two troughs. The result is a band of moderate
850mb to 700mb frontogenesis overlapping a slightly moister
environment and cold profile. This area of frontogenesis would
result in a quick moving band of moderate precip after midnight
Saturday through Sunday morning. Given precip rates, evaporative
cooling would allow for an all snow profile and some dusting would
be likely across areas along highway 84 and north. While we
mainly just kinda had a chuckle in the office about it and no
forecast should ever go off 1 run of 1 model it does hint at what
trend in guidance we would have to see in order to get wintry
precip. Given the trend in 99.9% of the guidance, we elected to
remove the mention of wintry precip from the grids; however, if
more guidance begins to trend towards the more in phased troughs
like the HRRR is showing then we may have to consider re-adding
the wintry mix with later issuances. Probability of this scenario
happening seems low (10% ish) and decreasing; however, there`s
still a tiny chance for you snow lovers. After that whole debacle
the trough pivots through pushing a surface cold front across the
area leading to a dry and cool Sunday through Monday night.
Surface northerly flow and high pressure aloft will keep skies
clear.
Temperatures will be cooler with highs climbing into the low 50s on
Sunday and mid to upper 50s on Monday. A few locations could see low
60s by Monday as the surface cold advection relaxes. Lows will be in
the upper 20s to low 30s Saturday and Sunday night before slowly
beginning to increase into the mid 30s on Monday night. BB/03
EXTENDED TERM /Tuesday Through Friday/...Zonal flow aloft
transitions into southwesterly flow early next week as an upper
level ridge begins to build in over the Caribbean. Meanwhile, a
developing upper level trough begins to dig across the western and
central CONUS. Surface high pressure is expected to dominate
across the eastern U.S. before moving out over the western
Atlantic on Wednesday. The progression of this surface high will
cause winds to become southeasterly which will enhance warm, moist
advection off of the Gulf waters on Tuesday and Wednesday. With the
surface high in place, dry and pleasant conditions will continue
for the early part of next week. Temperatures will also trend
warmer as a result of the southerly flow with highs reaching the
mid 60s to lower 70s. Although, lows will still be rather chilly
at night with temperatures falling into the upper 30s inland to
the mid 40s along the coast.
By Wednesday evening and into Thursday, conditions begin to
change as the aforementioned upper level trough becomes unphased
and a potent shortwave approaches the Plains and Mississippi
Valley. At the surface, a low pressure develops over the Central
Plains and tracks northeast and will bring a cold front through
the region sometime Thursday and Thursday night. We`re continuing
to monitor this system for the potential of severe storms and a
flood threat, but at this point in time it is difficult to iron
out the specifics for any hazards. Overall, guidance is in pretty
good agreement with this shortwave taking on a negative tilt on
Thursday with a strong upper level jet. A diffluent pattern aloft
also sets up which would support lift across the region.
Additionally, a strong low level jet looks develops over the
region on Thursday which would further enhance the warm, moist
advection off of the Gulf. Bulk shear does not look hard to come
by at this point with instability looking slightly more present
than in previous updates. We`ll continue to monitor these trends
as we get closer, but overall showers will be on the rise as we
head into mid next week with the potential for some strong to
severe storms. Temperatures continue on the warming trend through
Thursday, before drier and cooler conditions return in the wake
of the cold front. /14
MARINE...A weak ridge of high pressure will remain over the
marine area through Saturday. Winds becoming light southeasterly to
southerly through this evening. Winds will turn more westerly late
tonight ahead of an approaching cold front. Patchy fog may impact
area bays and sounds again late tonight into Saturday morning. A
strong northerly flow is expected Saturday night into Sunday
following the passage of the front. Conditions will become hazardous
for small craft over the weekend, and Small Craft Advisories will
likely be required for at least the Gulf marine zones during the
latter part of the weekend, with no less than Exercise Caution
levels (possibly SCA) for the bays and sounds. /12
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...Dense Fog Advisory from midnight tonight to 9 AM CST Saturday
for ALZ051>053-261>266.
FL...None.
MS...Dense Fog Advisory from midnight tonight to 9 AM CST Saturday
for MSZ067-075-076-078-079.
GM...Dense Fog Advisory from midnight tonight to 9 AM CST Saturday
for GMZ630>632.
&&
$$
This product is also available on the web at:
http://weather.gov/mob
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Morristown TN
800 PM EST Fri Feb 11 2022
.UPDATE...
EVENING UPDATE.
&&
.DISCUSSION...
Dewpoints remain fairly steady state this evening, but RH values
have risen above 30 percent most everywhere this evening thanks to
falling temperatures. Winds have also come down significantly as
well. All this to say that red flag conditions are no longer being
seen and went ahead and dropped the warning.
For the overnight hours, winds will remain elevated as a cold
front approaches from the west but will be far less than what was
seen today. In light of today`s guidance performance, felt it was
necessary to massage overnight dewpoints and temperatures. NBM
guidance seems too high on the former, and too low on the latter,
though mainly over the plateau in that regard. For dewpoints, did
a blend of current forecast with HRRR and the NBM 10th percentile
which fit current obs very well and seemed to be indicative of
what upstream dewpoints would advect in overnight. On the
temperature side of things, leaned more heavily towards the
CONSShort which warmed lows up a degree or two across the board,
with more notable increases over the plateau areas. Didn`t make
any changes to the forecast tomorrow as it seems to be in good
shape at the moment.
CD
&&
.AVIATION...
00Z TAF DISCUSSION.
VFR flight categories are expected through the overnight hours,
then lower into MVFR territory for KTYS and KTRI after daybreak
tomorrow as the cold front and precipitation moves in. Will
mention SHRA or VCSH at those locales too. KCHA likely remains VFR
and rain free. High pressure builds south into Arkansas tomorrow
so should see winds remain NLY to NWLY. This would yield downslope
flow off the plateau into KCHA as well which further gives
confidence in lack of MVFR CIGS there.
CD
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 46 55 26 44 22 / 10 10 0 10 0
Knoxville McGhee Tyson Airport, TN 45 52 27 41 20 / 10 20 20 10 0
Oak Ridge, TN 44 50 25 42 19 / 10 20 20 10 0
Tri Cities Airport, TN 42 50 28 38 18 / 10 30 40 20 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Pocatello ID
759 PM MST Fri Feb 11 2022
.UPDATE...
Seeing several observations including Idaho Falls and Burley
falling to 1/4sm visibility already this evening. Most of the
models don`t show fog developing until later and then keeping it
mainly patchy. Think most of the models may be too dry as our
forecast lows in the Snake Plain could be too cold although didn`t
raise the lows. The HRRR seems to have a better idea of where the
fog is as it expands rapidly from the INL region out to the
interstates which is what we`ve seen this evening. Have issued a
dense fog advisory until 17z. Some light icing on roadways is
possible, but as last night expecting that visibility will be the
main concern.
13
&&
.PREV DISCUSSION... /issued 136 PM MST Fri Feb 11 2022/
SHORT TERM...Tonight through Saturday night. Satellite imagery
shows significant erosion of the moisture trapped under the
inversion this afternoon. Observations show considerable
improvement in visibility as well, so have opted to cancel the
Dense Fog Advisory. Model soundings continue to favor a mix of
stratus and fog, and guidance still indicates potential for at
least locally dense fog in the Lower and Upper Snake Plain, but
spares the remainder of the region. Thus opted to broadbrush
patchy dense across the forecast for late tonight and will hold on
issuing another Dense Fog Advisory for now. A potential repeat is
expected Saturday night. DMH
LONG TERM...Sunday through next Friday. Upper ridge remains in
place through Sunday. Next upstream Pacific trough advances into the
NW coast late Sunday night and splits as it moves onshore across the
NRN Great Basin/Rockies Monday night/Tuesday. Typically we don`t get
a whole lot of moisture from splitting systems as they work through
the region and will float along with the National Blend of Models
here which shows some fairly decent precipitation potential for the
event with light to modest snow accumulations favoring the
mountains. Secondary energy trails across WRN Montana Wednesday
which is expected to provide ongoing support for snowfall across the
mountains through early Thursday morning. It looks like the ridge
rebounds across the region late next week and heading into the early
part of the weekend for a return to an inverted temperature regime
and drier conditions. Huston
AVIATION...Per the latest satellite imagery, it looks like the
fog and stratus are solidly entrenched across the Snake River
Plain and adjoining mountain-valley locations. Model time sections
continue to hint at some erosion occurring later this afternoon
and terminals may yet see a break in the LIFR CIGS and VSBY but as
time goes on, my optimism is fading on this point. Even if we do
get a break late this afternoon, it will likely be short-lived
with fog redeveloping across the region late tonight impacting all
terminals but perhaps KSUN and KBYI. Huston
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM MST Saturday for IDZ052>055.
&&
$$
Area Forecast Discussion
National Weather Service Phoenix AZ
505 PM MST Fri Feb 11 2022
.Update...Updated Aviation Discussion.
&&
.SYNOPSIS...
Strong high pressure situated along the West Coast will result
in clear skies and well above normal temperatures through early
next week. High temperatures in the upper 70s to as warm as 85
degrees are expected through Monday with no chance of
precipitation. A weather system is then expected to move through
the region next Tuesday and Wednesday bringing locally windy
conditions, chances for light precipitation, and pushing
temperatures back to below normal for the latter half of next
week.
&&
.DISCUSSION...
Latest water vapor imagery and RAP streamline analysis reveal a
broad ridge positioned off the California coast. Northerly flow
around the ridge is resulting in a continuation of the sunny skies
and seasonably dry conditions across the Desert Southwest. While
the strongest EFI temperature values are concentrated in
California, high temperatures as much as 10 to 15 degrees above
normal extend into portions of Arizona. However, probabilities for
record breaking temperatures are less than 5 percent today, even
in areas such as El Centro, California. For tonight and early
Saturday, a strong surface high building across the Rockies will
again result in breezy conditions, particularly across the
foothills of the Tonto National Forest.
Ensemble model suites remain in exceptionally good agreement over
the next several days, depicting the aforementioned ridge
persisting across the intermountain West, but gradually weakening.
Latest guidance indicates the above normal temperatures will
continue through Tuesday. Thereafter, an anomalously strong closed
low is likely to drop southward from the Pacific Northwest and
then sweep eastward through Arizona.
Cluster analysis indicates strong agreement between the ensemble
suites with a dominant cluster showing light precipitation
confined mainly to the higher terrain north and east of Phoenix.
Grand ensemble points to roughly a 40 percent chance of measurable
precipitation in the Valley, though the greater impact will be
the breezy/windy conditions preceding the system Tuesday and
sharply cooler conditions Wednesday. High temperatures in the
Phoenix area may only reach the lower to mid 60s, though the trend
continues to be colder. Model guidance also indicates a strong
signal for lower snow levels, though an unfavorable storm track
and limited moisture will likely yield only minor accumulations in
the higher terrain of Gila County. A warming and drying trend is
then expected in the wake of this system Thursday and Friday.
&&
.AVIATION...Updated at 0000Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Light westerly winds currently will switch to easterly around
04-05z and remain easterly through the rest of the period. A
northeasterly gradient is expected to develop overnight and
continue into Saturday morning before weakening Saturday
afternoon. This will result in an increase in low-level winds,
however LLWS is expected to remain mostly between 25-30 kts, below
the threshold of 30 kts for mention in TAF. As the nocturnal
inversion weakens by mid to late morning, some of the stronger
winds above the surface will mix down to create gusts of ~20 kts.
Winds will weaken by Saturday afternoon. Skies will remain mostly
clear.
Southeast California/Southwest Arizona including KIPL and KBLH:
No aviation concerns expected through the period. Aside from winds
becoming westerly tonight at KIPL, a northerly component is
favored. KBLH will experience winds of 7-10 kts and KIPL will
experience winds aob 5 kts. Skies will remain mostly clear.
&&
.FIRE WEATHER...
Sunday through Thursday:
Strong high pressure will persist early in the period with no
measurable precipitation and above normal temperatures prevailing
through at least Monday. A weather system is then likely to pass
through the region next Tuesday and Wednesday, but overall chances
for wetting rains look to be less than 30% and mainly over the
Arizona high terrain. Winds are likely to be the main impact with
the system with locally windy conditions on Tuesday and possibly
Wednesday. Much cooler temperatures are also expected by mid next
week. Humidity levels will remain quite low for much of the period
with Min RHs ranging between 7-15% through Monday before rising to
20-30% by Wednesday.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook, Twitter, and at weather.gov/phoenix
DISCUSSION...Hirsch
AVIATION...Lojero/18
FIRE WEATHER...Kuhlman
Area Forecast Discussion
National Weather Service Pueblo CO
329 PM MST Fri Feb 11 2022
.SHORT TERM...(This evening through Saturday)
Issued at 329 PM MST Fri Feb 11 2022
Key Messages:
1) Winter Wx Advisory Eastern Mountains and I-25 corridor this
evening, with brief snowfall rates of 1-2 inches per/hr producing
low visibility.
2) On average, total accumulations along I-25 will run from 1-3
inches, while eastern mountains and higher terrain west of the
Interstate see 3-6 inches.
Upper wave diving southward through the Rockies this afternoon, with
heavy banded snow dropping through the Denver metro as of 22z.
Mesoscale models and radar trends are in good agreement for this
evening, bringing at lighter snow to the Pikes Peak region and
portions of the plains north of the Arkansas River before 5 pm, then
heavier snow band setting up over El Paso County beginning 5-6 pm,
before shifting slowing southward toward the NM border through
the evening. Heaviest snow will likely occur in the 5 pm-10 pm range
at most locations, and judging from obs in the Denver area, a few
brief periods of 1-2 inch per/hr rates and visibility below 1/2sm
are likely along and west of I-25 this evening. Snow ends from north
to south fairly quickly after midnight, and should be out of the
region by sunrise on Sat morning. Made just a few small changes to
previously forecast storm total accumulations for the event, nudging
snow amounts and qpf upward slightly around Colorado Springs and
Pueblo, where HRRR shows heavier band setting up this evening.
Mainly minor blowing/drifting expected as lower elevation winds stay
in the 10-20 kt range, mountains a little stronger with slightly
more areas of blowing snow over higher exposed peaks/ridges.
On Saturday, clearing skies and generally light winds in the wake of
the upper wave, with temperatures staying slightly cooler than
seasonal averages at most locations. Did trim a few degf from maxes
along the I-25 corridor to account for expected snow cover, though
readings should still be warm enough to melt a good deal of snow, at
least at lower elevations.
.LONG TERM...(Saturday night through Friday)
Issued at 329 PM MST Fri Feb 11 2022
...A warming trend into the weekend with snow and colder
temperatures for the middle of next week...
Saturday night-Sunday...Moderating north to northwest flow aloft
remains progged across the region into the weekend. This will bring
dry conditions and warmer temperatures to the area, with highs on
Sunday expected to be in the 50s to lower 60s across the plains,
with temperatures mainly in the 30s and 40s across the higher
terrain.
Sunday night-Tuesday...Flow aloft looks to become more westerly
across the region into early next week, as models continue to
indicate eastern Pacific energy moving onshore across the Pacific
Northwest on Monday, which then continues to translate across the
Intermountain West through the day on Tuesday. This pattern will
again keep dry, warm and occasionally breezy weather in place across
the region through the day on Tuesday.
Tuesday night-Friday...While operational models do agree on the
eastern Pacific energy moving across the Intermountain West on
Tuesday, there remains a lot of variability in the timing, location
and strength of this system as it moves across the Rockies in the
Tuesday night through Thursday night timeframe. Most of the ensemble
mean data suggests the main portion of this system digging south
into southern Arizona before lifting out across the southern
Rockies, however, there is some support to secondary energy also
digging across the northern and central Rockies through this
timeframe, leading to a variety of possible outcomes across south
central and southeast Colorado.
At any rate, timing of the greatest impacts of this system
eventually moving across the region seems to be later Wednesday
morning and afternoon, with the most widespread snowfall Wednesday
night before slowly tapering off through the day on Thursday. Total
snow accumulations through this timeframe will remain in flux until
the track of this system becomes more defined, however the greatest
amounts look to favor areas over and near the eastern mts. After
very warm temperatures on Tuesday, highs on Wednesday and Thursday
look to fall below seasonal levels, with a slow warming and drying
trend expected across the region on Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 329 PM MST Fri Feb 11 2022
At KCOS and KPUB, expect a period of IFR vis from roughly
00z-07z as main band of snow drops south through the area. Current
thinking is still 1-3 inches of accumulation possible at both
terminals. N-NE winds at 10-20 kts will slowly diminish
through the evening. Conditions improve back to VFR after 07z
as snow ends and ceilings rise, with VFR through the day on Sat.
At KALS, prevailing conditions will be VFR overnight, but
with a low risk of a -shsn and brief MVFR vis 02z-06z as a weak
weather system moves through the area. Will carry vcsh for now,
may need a brief tempo group for showers this evening, though will
monitor radar trends before adding anything. On Sat, VFR.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 PM MST this evening for COZ083-
085-086.
Winter Weather Advisory until 11 PM MST this evening for COZ081-
082-084.
Winter Weather Advisory from 6 PM this evening to 2 AM MST
Saturday for COZ074-075-087-088.
Winter Weather Advisory until 2 AM MST Saturday for COZ079-080.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...MW
AVIATION...PETERSEN