Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/17/22
Area Forecast Discussion
National Weather Service Cleveland OH
1010 PM EST Wed Feb 16 2022
.SYNOPSIS...
A strong low pressure system will move northeast into the Ohio
Valley along a nearly stalled cold front tonight into Thursday. The
cold front will slowly move southeast across the area on
Thursday followed by lingering troughing on Thursday night into
Friday. High pressure will briefly settle across the region on
Friday, followed by another strong low pressure system and cold
front on Saturday. High pressure will return across the region by
the end of the weekend.
&&
.NEAR TERM /THROUGH THURSDAY NIGHT/...
Update...
Most of the near-term forecast remains valid. The boundary
layer has stabilized slightly via nocturnal cooling. RAP
forecast mean boundary layer winds and 0-1 km AGL lapse rates,
and model soundings in BUFKIT continue to suggest a relatively-
stable boundary layer will promote shallow mechanical mixing. Do
not expect this mixing to tap into much stronger flow aloft,
including a SSW`erly to SW`erly LLJ of about 50 to 65 knots at
925 mb over our CWA, through mid to late Thursday morning. Any
peak surface gusts through Thursday morning will probably be
about 20 to 35 knots at most. Accordingly, the Wind Advisory has
been cancelled. Only other change was to adjust the Winter
Weather Advisory to be in effect from 4 PM Thursday to 7 AM EST
Friday for Lorain, Cuyahoga, Medina, and counties farther east.
This was based on our official forecast and trends seen in the
00Z/Thurs runs of the HRRR and NAM. Will let the overnight shift
analyze the full 00Z/Thurs suite of model guidance before
deciding whether to expand the advisory farther east and south.
Previous Discussion...
An active 36 hours is in store across the region with hazards
ranging from gusty winds, significant river flooding, the
potential for ice jams, and slippery road conditions from heavy
mixed- precipitation including snow, sleet, and ice. A flood
watch remains in effect for the entire region for the
significant river flooding threat, in addition to an extension
of the wind advisory this evening and tonight. A winter weather
advisory is now in effect for portions of NW OH and northern OH
for a period of moderate to heavy mixed- precipitation late
Thursday afternoon and evening.
For the rest of today, we`ll continue to see an increase of clouds
across the region as southerly wind gusts remain elevated in the 40
to 50 mph range. We may see a resurgence of some of these elevated
winds later this evening and overnight as the surface low and
associated cold front approach central MI, increasing the pressure
gradient across the region and resulting in a 55 to 60 knot 925 mb
jet. The aforementioned cold front will slowly sag southeast across
MI, reaching NW OH by mid-Thursday morning, and continuing to move
southeast throughout the day. The cold front may briefly stall
across the far southeast portion of our area from Mount Vernon to
Youngstown late in the day as a stronger low pressure system moves
northeast along the front, reaching the Ohio Valley by Thursday
evening.
Precipitation will begin as rain for the entire area Thursday
morning and even into the early afternoon. A changeover to freezing
rain and sleet for NW OH and northern OH is not anticipated until
the arrival of the stronger low pressure system Thursday afternoon
and evening as a strong, southwesterly 700 mb jet arrives and
overruns the cooler air below and near the surface. This could
result in an enhanced period of freezing rain and sleet in the
advisory area, with a half inch to an inch of sleet and up to a
tenth of an inch of ice possible late Thursday afternoon and
evening. Additional snow accumulations of generally 1 to 3 inches is
possible behind the sleet and ice activity. The higher end of the
snow amounts will most likely be found across far NW OH near the
Toledo area. An extension of the winter weather advisory is possible
across NW PA if current mixed-precipitation trends continue. We will
need to monitor the flash-freeze threat late Thursday night into
Friday morning as low temperatures will plummet into the low teens
to perhaps single digits behind the strong cold front.
Total precipitation amounts continue to be in the 1.5 to 2.0 inch
range which, combined with continued snowmelt tonight into Thursday,
will cause significant issues, especially across our area rivers and
streams. Recent snow-water equivalent measurements suggest a water-
logged snowpack holding as much as 1 to 2 inches of liquid. Several
of our area rivers are forecast to go into moderate and major flood
levels for which warnings have been issued in the highest-confidence
river forecast points. Stay tuned for more river warnings as the
event unfolds. In addition, ice jams along ice-covered rivers also
remain possible, given the extended period of warmer air and
rainfall.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The surface cold front will be well east of the region by Friday
morning, with the upper level trough lingering through Friday
afternoon. Low level winds look to align and become westerly by
Friday afternoon. Additionally, 850 mb temperatures will be cooler
as upper level CAA takes hold behind the passing of the trough. This
could allow for some lake effect to take place on Friday morning,
however with dry air quickly moving into place, accumulations should
be minimal and short lived. We will remain dry for the rest of the
afternoon and evening on Friday ahead of the next system. A low
pressure system and its associated 500 mb vorticity maximum will
move across the northern Midwest before entering our region by
overnight Friday into Saturday morning. The moisture associated with
this fast moving Alberta Clipper will bring light snow to the area
during the early hours on Saturday morning. Snow will eventually
transition into lake effect/lake enhanced across our snow belt
counties. The clipper quickly moves eastward and will be out of the
region by Saturday evening. High pressure begins to take hold and
upper level flow returns to a zonal pattern by Saturday night.
The passing cold front from Thursday evening will allow for
temperatures on Friday morning to be cooler and in the upper teens
to low 20s. By Friday afternoon, temperatures will rise into the mid-
to-upper 20s and remain there through Saturday evening. Temperatures
overnight Saturday into Sunday morning will be in the low 20s across
the CWA.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
High pressure will move into place on Sunday, but won`t stay for
long. Surface high pressure will shift east of the region by Sunday
evening. As the upper level flow remains zonal, we should remain dry
on Monday ahead of our next system. Tuesday brings a change in
conditions. A low pressure system and its associated shortwave will
move northeastward into the region Tuesday. Plenty of moisture
will be in place and southerly flow will bring in warm moist air
from the Gulf of Mexico making this a mostly rain event across
the region. The surface low will leave the region by Wednesday
afternoon with high pressure settling in its wake.
Temperatures in the long term period will remain above average and
mild for this time of year. Highs will be in the upper 40s to mid
50s across the CWA through Tuesday. Temperatures will be cooler on
Wednesday but still above average for this time of year.
&&
.AVIATION /00Z Thursday THROUGH Monday/...
A surface high pressure ridge will exit eastward slowly as a
cold front approaches from the northwest. This front should
begin to drift southeastward across our region after 12Z/Thurs
and near a line in vicinity of KGKJ/KYNG/KCAK/KMRT by 00Z/Fri.
Simultaneously, a surface low should develop northeastward
along the front and near the Mid-OH Valley by 00Z/Fri as another
surface high pressure ridge builds behind the front. Southerly
to southwesterly surface winds of about 10 to 20 knots ahead of
the front should veer abruptly to northwesterly and then to
northeasterly behind the front. Gusts up to about 20 to 30 knots
are possible, especially behind the front. Of note, LLWS is
possible through about 12Z or 15Z/Thurs due a southwesterly low-
level jet of about 50 to 65 knots at 925 mb.
Scattered and light rain showers are possible well-ahead of the
cold front. Widespread light to moderate rain and MVFR to IFR
ceilings, in vicinity of and behind the front, should
overspread our area from the northwest between about 11Z and
16Z/Thurs. The light to moderate rain should begin to change to
a freezing rain/sleet mix after roughly 17Z/Thurs as colder air
at/near the surface follows the cold front and undercuts warmer
air farther aloft. This freezing rain/sleet mix should progress
southeastward to roughly a KBKL/KCLE to KAOH line by 00Z/Fri.
Visibility should vary between MVFR and LIFR in the precip, with
the lowest visibility expected where predominantly sleet
occurs.
Outlook...Non-VFR likely in widespread mixed precip Thursday
night. Periods of snow with non-VFR possible Friday through
Saturday, especially in northeast OH and northwest PA. Scattered
rain showers with non-VFR possible on Monday.
&&
.MARINE...
Winds will diminish and become southerly at 20 to 25 knots overnight
Wednesday. A cold front will cross Lake Erie Thursday morning and
bring plenty of precipitation along with it. Winds will shift with
the passing front and become northeasterly at 10-15 knots Thursday
morning, and northerly by Thursday afternoon remaining between 10-15
knots. Winds will briefly increase across the lake between 20 and 25
knots by overnight Thursday through Friday morning. Winds decrease
to 10-15 knots by Friday morning, remaining northeasterly. Another
cold front will sweep across the Great Lakes region on Saturday
causing winds to increase to 25-30 knots and shift to come from the
southwest. By Saturday afternoon winds diminish to 10-15 knots over
the lake. Winds are expected to increase again on Sunday with high
pressure in place southeast of the Great Lakes, winds will be
southerly ranging between 20 and 25 knots.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Flood Watch through late Thursday night for OHZ003-006>014-
017>023-027>033-036>038-047-089.
Winter Weather Advisory from 4 PM Thursday to 7 AM EST Friday
for OHZ010>014-020-021-089.
Winter Weather Advisory from 1 PM Thursday to 1 AM EST Friday
for OHZ003-006>009-017>019-027-028.
Winter Weather Advisory from 4 PM Thursday to 1 AM EST Friday
for OHZ029>031.
PA...Flood Watch through late Thursday night for PAZ001>003.
MARINE...None.
&&
$$
SYNOPSIS...Kahn
NEAR TERM...Jaszka/Kahn
SHORT TERM...Iverson
LONG TERM...Iverson
AVIATION...Jaszka
MARINE...Iverson
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
523 PM CST Wed Feb 16 2022
.AVIATION...
All airports are VFR at this time, but this will be short lived. MVFR
ceilings will return to Austin and San Antonio by around 02Z this
evening. DRT will remain VFR through the entire period. Strong gusty
southerly winds will continue at all terminals through the night. A
dryline will move through the region early Thursday morning. This
will turn the winds to the west. A cold front will follow the dryline
turning the winds again this time to the northwest. Wind speeds will
increase and become gusty behind the front.
&&
.PREV DISCUSSION... /ISSUED 221 PM CST Wed Feb 16 2022/
SHORT TERM (Tonight through Thursday Night)...
Brisk southerly winds, particularly over the eastern half of south-
central Texas, have generally been in the 10-20 mph range, locally
up to 25. Gusts of 25-35 mph have been observed as well with a few
higher values from time to time. Seasonally warm and humid
conditions continue, and dew points in the 50s and low 60s will tick
up a tad for many locations as we head into the overnight. Drizzle
and very light rain showers ongoing along and east of Austin to
Cuero will lift off to the NE late this afternoon but could return
late tonight.
RAP analysis currently places an H5 trough axis over the four
corners region. It will push east to TX tonight before lifting NE
and allowing sfc cyclogenesis to our north. A WNW to NW wind shift
will quickly move through late tonight through mid-morning Thursday,
and with it will come a very low chance for a shower or two mainly
northeast of Fredericksburg to Cuero, with the best chances north of
Austin, where a rumble of thunder cannot be ruled out. Most areas
will stay dry though, unfortunately.
Wind speeds behind the dryline will be largely in the 10-20 mph
range with gusts to 35 once again. The highest winds should come
within the first few hours of the boundary passage for locations
west of US-281, but a cold front will arrive tomorrow evening with
due N winds increasing once again across the entirety of the region.
In the interim, temperatures will remain relatively warm tomorrow
afternoon, mostly in the 60s in the Hill Country but mid to upper
70s south of I-10/US-90. Critical Fire Weather conditions are
forecast, with the worst conditions southwest of San Antonio, but
with additional grass loading east and a recent history of fires a
Red Flag Warning will be in place for the entire CWA during the day.
The push of colder air Thursday evening will bring a freeze to the
Hill Country early Friday morning. May also see locations like
Caldwell and Bastrop Counties briefly dip below freezing. Gusts will
remain elevated through the evening, particularly over the higher
terrain between Boerne and Del Rio. Wind speeds should gradually
slacken after midnight, but wind chill values in the low 20s are
possible north early Friday.
LONG TERM (Friday through Wednesday)...
After a cool start of the day with a light hard freeze across
parts of the Hill Country and upper 20s to mid 30s across the rest
of the area, a warming trend is in store for Friday. Even though
highs are forecast to stay slightly below climate normal values,
upper 50s to mid 60s are just fine for this time of the year. Skies
will remain sunny throughout the day with a few clouds mainly across
the Coastal Plains. Light to moderate northeast winds are expected
on Friday with minimum relative humidities in the teens and lower
20s for areas across the southern Edwards Plateau and Rio Grande
Plains, creating elevated fire weather concerns. Can`t rule out an
isolated or two spots reaching near critical fire criteria.
During Friday night into Saturday morning, a wind shift from the
northeast to the southeast brings increased moisture and low clouds
to the Coastal Plains and most areas across our CWA. Overnight lows
in the 30s over most places. Once clouds erode mid to late morning
across the Hill Country and across the southern half of the area in
the afternoon, temperatures will climb into the 60s and 70s. With a
dry airmass still in place, minimum relative humidities will sink to
the teens and lower 20s over most locations. However, light
southerly winds are forecast to stay in place with breezy conditions
across Val Verde and Edwards Counties for elevated fire weather
concerns. Can`t rule out an hour or two of near critical values
across the northwest part of Val Verde County.
Upper level zonal flow is forecast for Saturday night into Sunday
with the flow shifting to the southwest on Sunday afternoon into
Monday morning as an upper level short wave moves across northern
Mexico into the Southern Plains. The GFS is faster with this feature
than the ECMWF by about 6 hours or so. As the pulse of energy pushes
across the area, there should be enough moisture in place to generate
scattered showers and isolated thunder activity across the area,
however, favoring locations along and east of Interstate 35 and
Interstate 37.
Slight to low end chances for showers and isolated thunderstorms are
possible on Tuesday as the GFS solution shows a Pacific front
pushing across the area. The ECMWF guidance brings the frontal
boundary on Wednesday with most of the QPF activity happening across
the northern part of the Hill Country. Went with a blend for this
particular period with chances for showers and isolated thunderstorms
since the GFS also shows a good signal for precipitation.
FIRE WEATHER...
A dry airmass will begin to move in late tonight as winds shift to
the NW. Winds will increase again into the 10-20 mph range with
gusts of 25 to 35 mph once again behind the boundary. By late
morning, we expect RH values to begin falling below 20 percent over
the Winter Garden Region and they`ll minimize in the lower teens
there. Elsewhere, MinRH in the teens to low 30s are forecast,
highest from Austin northeastward. While there will be some
moderation in the wind gusts in the midday hours, a cold front will
bring a shift to due N winds and speeds will increase again through
the evening as RH begins to recover. Locations west of I-37 and
south of US-90 will see the most overlap of gusty winds and dry air
on Thursday, however a Red Flag Warning will be in effect through
the daytime across the entirety of south-central TX.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 58 70 32 57 35 / 20 - 0 0 0
Austin Bergstrom Intl Airport 59 71 32 58 32 / 20 - 0 0 0
New Braunfels Muni Airport 59 75 34 60 34 / 20 0 0 0 0
Burnet Muni Airport 53 66 29 56 32 / 20 0 0 0 0
Del Rio Intl Airport 54 73 38 64 38 / - 0 0 0 0
Georgetown Muni Airport 57 67 31 57 33 / 20 10 0 0 0
Hondo Muni Airport 53 79 33 63 33 / 10 0 0 0 0
San Marcos Muni Airport 58 73 32 58 33 / 20 - 0 0 0
La Grange - Fayette Regional 64 76 35 57 35 / 20 20 0 0 0
San Antonio Intl Airport 59 75 35 60 37 / 10 0 0 0 0
Stinson Muni Airport 61 78 38 62 37 / 10 0 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 9 AM to 8 PM CST Thursday for Atascosa-
Bandera-Bastrop-Bexar-Blanco-Burnet-Caldwell-Comal-De Witt-Dimmit-
Edwards-Fayette-Frio-Gillespie-Gonzales-Guadalupe-Hays-Karnes-
Kendall-Kerr-Kinney-Lavaca-Lee-Llano-Maverick-Medina-Real-Travis-
Uvalde-Val Verde-Williamson-Wilson-Zavala.
&&
$$
Short-Term/Aviation...05
Long-Term...76
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
545 PM CST Wed Feb 16 2022
...AVIATION UPDATE...
.DISCUSSION...(This evening through Wednesday)
Issued at 248 PM CST Wed Feb 16 2022
Main challenge for this forecast will be stratus today and wind
gusts tonight, with possible light snow nearby. Also, cold snap
arriving next week as models and ensembles clearly trend colder.
For tonight, there is some light snow possible from mid-level
frontogenetic forcing, especially in our west/northwest tonight
before the main show really starts ramping up with the shortwave
trough swinging through within northwest/west flow. Not a whole
lot of support for big snow amounts. Models continue to trend
south with southern Plains system. Low chances of very low qpf in
our far south. Was liberal with flurries considering the extra
cold air advection push we get tonight. The RAP predicts some
flurry activity for much of the CWA later on. For the most part,
we are missed with the winter system to our south/southeast. Wind
speeds pick up a bit with surface pressure gradient tightening.
Temperatures continue to trend cold for Thursday and wind will
still be brisk, lending to a rather brisk raw day. Winds will
finally decrease as the pressure gradient decreases. General
warmup Friday through the weekend on track with fire weather
concerns, especially Saturday.
Major transition ensues on Monday as an arctic cold front moves
through, introducing much colder air, and by Tuesday, forecast
highs are in the teens to lower 20s as temps continue to plummet
in ensembles. Looks more and more likely for teens for highs
Tuesday and perhaps Wednesday, if trends continue to look this
way.
This will likely introduce a prolonged cold snap, with below
normal temps into early March according to both ECMWF and GFS
ensembles. Ensembles also point toward an accumulating snow
situation in the Thursday/Thursday night time frame next week,
with GFS ensembles more favorable with a more northern track,
swiping our southeast. Still outside of the range of this
forecast, but something to keep an eye on.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 543 PM CST Wed Feb 16 2022
Significant weather: Persistent gusty N/NNW winds.
VFR through the period. Abundant cloud cover has overspread the
terminals with CIGs around 4-5K ft. These may lower slightly, but
nearly all guidance keeps both terminals VFR. Included a VCSH
group at EAR for maybe some flurries, but greatest potential for
impactful snow should bypass the area. CIGs will raise towards
dawn and clds should decr thru the daytime Thu. Brzy N to NNW
winds are expected for much of the period, with a significant decr
in speeds likely not arriving until Thu aftn. Confidence: Flt
Cat/CIGs - medium, wind - high.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
DISCUSSION...Heinlein
AVIATION...Thies
Area Forecast Discussion
National Weather Service Grand Rapids MI
847 PM EST Wed Feb 16 2022
LATEST UPDATE...
Update
.UPDATE...
Issued at 839 PM EST Wed Feb 16 2022
The main change to the forecast with the update was to add some
fog to the forecast. Fog has been on the increase across
northwestern parts of the CWA including the Hart area which is
down to a half mile. The relatively warm and moist airmass ahead
of the front was interacting with the snowpack and colder waters
over Lake MI to lead to fog in that area. As the front pushes down
from the northwest...the fog should move into/develop for much of
the remainder of the CWA tonight. The latest HRRR does indicate
that locally dense for could occur...especially closer to Lake MI.
Any fog should dissipate as the colder air moves back in from the
northwest later tonight. For now we will include fog with the
update...mainly patchy.
We did notice a few thunderstorms in Illinois tracking northeast.
Based on the forecast elevated instability...the potential for
thunderstorms should remain south of the CWA tonight.
UPDATE Issued at 642 PM EST Wed Feb 16 2022
The winds will largely remain below gale force but still hazardous
to small craft over the next couple of periods. The front will
drop southward through the zones this evening causing the winds
to become northerly and gusty over the lake as the cold air
advection strengthens. Based on forecast mixing heights and winds
at those levels gusts in the 25 to 30 knot range will be common
into Thursday evening.
&&
.DISCUSSION...(This evening through next Wednesday)
Issued at 355 PM EST Wed Feb 16 2022
- Rain tonight changing to mixed precip then snow late
Moisture transport from the Gulf is pooling across Lower Michigan
ahead of advancing cold front. Light rain this evening in area of
strengthening isentropic ascent/warm advection will be focused by
the front trailing a northern stream low moving across Canada.
Cold air behind the front gradually seeps in overnight from the
northwest with rain changing over to a brief period of freezing
rain and sleet and then snow as surface temperatures fall back
below freezing with light accumulations causing some icy roads for
the morning commute. This is the reason we began the winter
weather headlines early, even though there will be a break in the
precip until the snow returns for the afternoon with the southern
stream low.
Model soundings continue to show that the transition from rain to
snow should be rather quick, with only about an hour long window
when some sleet or freezing rain is possible, so icing from
freezing rain is not expected to be much of a threat.
- Snow on Thursday afternoon and evening
The front clears the southern zones in the morning with only light
residual snows behind the front, which taper off and end before
noon. The area of f-gen associated with the southern stream low
then arrives during the afternoon with mesoscale banding most
likely across the far southern and southeast forecast area, with
Jackson County having the best chance to see totals greater than 6
inches in 12 hours.
The models are in agreement on a broad area of weaker mid level
frontogenetic forcing further north with Grand Rapids and Lansing
near the northern edge of it during the afternoon. Snow totals of
1 to 3 inches can be expected there, with 2 to 5 in the zone in
between I-96 and 1-94. The snow tapers off during the evening as
the area of f-gen and deformation axis moves east.
- Clipper on Friday night
Clipper low passes north of the forecast area on Friday evening
with some lake-enhanced snow and low-level convergence bringing a
general 1 to 2 inch snow event with some locally high amounts.
- More storminess early next week
Active pattern continues next week with a couple southern stream
lows tracking near or south of Lower Michigan in the Tuesday
through Wednesday or Thursday time frame. At this point it looks
like enough cold air will be present to bring the chance of wintry
precip, especially on Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 642 PM EST Wed Feb 16 2022
The southwest winds will remain gusty this evening as the cold
front drops down from the northwest. The winds will shift to the
northwest to north behind the front for later tonight into
Thursday. Colder air will flow in as the front drops in and the
numerous rain showers will transition to a wintry mix leading to
hazardous aviation conditions especially later tonight into early
Thursday morning. IFR conditions will move in as the front arrives
and then persist into Thursday morning. There will be a lull the
precipitation during part of Thursday...but as a low pressure
system approaches from the southwest later in the day...snow will
be spreading in from the southwest. KMKG may be too far north to
see any snow from this system which is why we have held off on any
afternoon snow for that site.
&&
.MARINE...
Issued at 355 PM EST Wed Feb 16 2022
The Gale Warning continues through 7 pm and it will either be
extended or replaced with a Small Craft Advisory at that time
depending on the current wind forecast, as it looks like
conditions will be on the cusp between 30 to 35 knot wind gusts
later tonight and Thursday.
&&
.HYDROLOGY...
Issued at 355 PM EST Wed Feb 16 2022
Rapid snowmelt is underway for much of West Michigan. This will
continue overnight, as rain moves in this evening and speeds melting
up even more. Our best estimate is that around 1 inch of water will
be melting out of the snowpack, and add on to around three-quarters
of an inch of rain expected tonight. This is going to make for a
sloppy mess with lots of standing water in low spots and poor
drainage areas for the next day or two. Frozen ground is going to
make this worse, simply because the water won`t be able to soak in
much at all.
As all this water starts finding its way to our rivers and streams,
water levels will come up dramatically. We`re not expecting any
widespread significant flooding on the rivers, but some of the
medium-sized rivers - particularly in the Lansing area - will
probably come up to bankfull over the next few days.
The main hydro concern continues to be the risk of ice jams, as the
water rises and forces ice to break up and move. Our main concern is
the Grand River - and the streams that flow into it - simply because
this is where the most river ice is located. The Kalamazoo River has
a lot of open water, so the risks are a bit lower there, even though
there will still be notable increases in water levels. The ice jam
threat will begin Thursday/Friday for the medium sized rivers, and
then shift more to the Grand River itself by this weekend (it takes
time for the water to flow through the river system!).
It`s worth repeating again that ice jams are notoriously
unpredictable. and their formation is not guaranteed. However, if an
ice jam does form, it`s important to remember that water levels can
come up (and down) much faster than you might be used to for our
West Michigan rivers. Report all flooding to local authorities or
the National Weather Service as soon as you safely can.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Storm Warning from 6 AM Thursday to 1 AM EST Friday for
MIZ073-074.
Winter Weather Advisory from 6 AM Thursday to 1 AM EST Friday
for MIZ065>067-071-072.
LM...Small Craft Advisory until 11 PM EST Thursday for LMZ844>849.
&&
$$
UPDATE...MJS
DISCUSSION...Ostuno
AVIATION...MJS
HYDROLOGY...AMD
MARINE...Ostuno
Area Forecast Discussion
National Weather Service Houston/Galveston TX
525 PM CST Wed Feb 16 2022
.AVIATION [00Z TAF Issuance]...
Some light showers and patchy fog has popped up in the southerly
flow across the area bringing some reduced visibilities down to
around 1 to 2 miles at times for terminals north of I-10. The
shower activity should wane for a few hours after sunset, however
CIGs will be lowering to 700 to 1500ft for most of the area that
will persist through tomorrow morning. Sea fog may bring some
periods of dense fog to GLS during the late night/early morning
timeframe. Two boundary will be passing through the area
tomorrow, the first being a dry line that pushes through in the
early to mid morning that brings an increase in shower activity
for the northern half of the area and ushers in a westerly wind
across the entire area. Then a cold front moves through in the
afternoon bringing a northerly wind shift. The southerly winds
tonight will continue to gust to 20 to 30kts, and the strong wind
gusts will persist with the westerly and northerly wind shifts
tomorrow.
Fowler
&&
.PREV DISCUSSION /Issued 306 PM CST Wed Feb 16 2022/...
.SHORT TERM [Today Through Thursday Night]...
Wednesday...more like "winds-day" am I right?! It`s another windy
one out there with 850mb winds around 35-40 knots in combination
with steep low-level lapse rates past 1km and unidirectional flow
aloft. A Wind Advisory remains in effect till 6pm for counties west
of the Brazos River as a result. Look for the 850mb winds to
increase further going into the overnight hours as the LLJ
strengthens ahead of FROPA. We`ll jump back to that in the next
paragraph. WAA continues this afternoon along with persisting
onshore flow, and with sufficient mixing (hello gusty winds),
temperatures have been able to reach the mid to upper 70s.
Spotty rain showers have popped up throughout the day, mainly
west of I-45 where moisture availability is slightly more
favorable. Dry air remains above 850mb, so there isn`t much room
for enough moisture to develop anything more than light
rain...for now. Speaking of rain, let`s talk about
thunderstorms...or the lack of them this afternoon/evening. We
have a pretty stout capping inversion in place generally from
850mb-700 mb with CIN around -150 to -100 J/kg across our northern
counties. Suffice to say...not gonna get much of anything
punching through that without a lifting mechanism, and the front
is still quite a ways out at this point (relatively speaking).
After 06Z on Thursday (midnight), 850mb winds substantially increase
to 60-70 knots. With WAA becoming strong along with a thick blanket
of MVFR cloud ceilings, I bumped up tonight`s temperatures a bit to
reflect lows in mid 60s. Along the coast, winds may taper off enough
along Galveston Bay early Thursday morning to allow some sea fog to
briefly roll in. Model trends are pointing towards this only
impacting Galveston Island/Bolivar Peninsula until the winds switch
around. A pre-frontal trough will push through the region in the
early morning hours and will be the boundary that moisture converges
along. PWATs surge to 1.5"-1.7" along this boundary, so heavy rain
is possible in any of the stronger updrafts that manage to develop.
This is more likely for our northeastern counties, where there is
also the best chance of hearing a few claps of thunder. The 12Z CAMs
differ a bit in terms of SHRA coverage for Thursday morning with the
HRRR and NAM3km less aggressive on coverage and depict our
southwestern counties not receiving much if any rain.
The high temperature forecast for Thursday is pretty tricky based on
FROPA timing. With temperatures in the mid 60s overnight, should see
them rise to at least the low 70s up north just before the front
moves through. Further south, there`s plenty of time for prefrontal
heating to raise temperatures into the upper 70s (isolated spots
hitting 80). The cold front pushes through shortly after the pre-
frontal trough in the afternoon to the tune of moderate northerly
winds as dry air funnels in and CAA prevails. Expect the skies to
gradually clear through Thursday afternoon, but some high clouds may
redevelop on Thursday night with a shortwave trough still lingering
over Texas.
Northerly winds around 15 knots will prevail into Thursday night,
so we`re not looking at exactly a prime setup for max radiational
cooling. However, it`ll still get pretty cold with a light freeze
for our northern counties as lows drop into the low to mid 30s
north of I-10 and the mid to upper 30s to the south. The
prevailing winds will make it FEEL like we had max radiational
cooling though! Wind chill values on Thursday night/Friday morning
will be as low as the lower 20s around the Brazos Valley and the
upper 20s in the Houston metro area and southward.
Batiste
.LONG TERM [Friday Through Wednesday]...
Surface high pressure moving slowly eastward across the north Texas
area will keep our area cool and quiet to close out the week.
Elevated north winds in the morning (especially near/along the
coast) will weaken as the day progresses. High temperatures in the
mid to upper 50s can be expected with maybe a spot or two reaching
60 degrees between the Houston area and the Matagorda Bay area. The
high will be moving off to the east over the weekend, and this will
allow for southeast winds to return to the area and set up a warming
trend. Before those temperatures begin to warm up, inland lows
mostly in the 30s can be expected Friday night with a few far
northern spots at or slightly below freezing. Saturday`s highs will
be back into the 60s (probably closer to the mid to upper 50s at the
coast) followed by Saturday night`s lows in the 30s/40s).
Strengthening southeast to south winds on Sunday will help to boost
afternoon high temperatures closer to 70 degrees, and this flow will
support a significant increase in cloud cover as the day progresses
eastward. Low rain chances are back into the forecast Sunday
afternoon and evening with better rain chances coming during the
first half of next week as disturbances/impulses begin to track
across the state in an increasingly active southwest flow aloft.
Currently carrying best rain chances Monday and then again Tuesday
and Wednesday (higher across our north and northwest areas and lower
across our southwest areas), but this timing will likely change over
the next several days as we await for better model/consensus
agreement. If you like it warmer, Monday`s and Tuesday`s highs could
be approaching 80 degrees. 42
.MARINE...
Onshore winds will continue to strengthen and seas will continue to
build tonight. Will carry Caution flags for the bays and Advisories
for the 00-60 nm waters). Patchy sea fog is possible tonight as
surface dew points remain above bay water temperatures, but fog
development may be inhibited by the elevated winds. A cold front and
accompanying showers will push through the coastal waters Thursday
afternoon. Strong offshore winds and building seas can be expected
to develop behind the front with Gale conditions possible Thursday
night through early Friday morning (a Gale Watch has been issued).
Winds and seas will come down Friday and on through the weekend as
high pressure builds into the area but will shift to the southeast
on Sunday as the high moves off to the east. A strengthening onshore
flow and building seas can be expected for the start of next week
with more cautions/advisories anticipated. 42
.FIRE WEATHER...
Moderate and gusty southeasterly winds will persist through Thursday
morning/early afternoon when a prefrontal trough and cold front
pushes through the region. Winds at 850mb (~4500 ft) are around
35-40 knots this afternoon, but will increase to 60-70 knots
overnight ahead of the front. RH values this afternoon remain
relatively high (55%-65%) with onshore flow prevailing, but will
drop substantially on Thursday as drier air filters in. On
Thursday afternoon, expect min RH values around 30%-35% along
with gusty northerly winds. Winds become lighter by Friday, but RH
values will remain on the low side with another day in the range
of 30%-35% and even lower on Saturday with a range of 25%-30%.
Onshore flow returns Saturday night leading to increasing moisture
heading into Sunday.
Batiste
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 64 73 32 57 33 / 40 30 0 0 0
Houston (IAH) 65 77 36 57 38 / 30 50 0 0 0
Galveston (GLS) 61 72 41 57 47 / 20 50 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until 6 PM CST this evening for the following
zones: Austin...Brazos...Burleson...Coastal
Jackson...Coastal Matagorda...Colorado...Inland
Jackson...Inland Matagorda...Matagorda
Islands...Washington...Wharton.
High Rip Current Risk through Thursday morning for the following
zones: Bolivar Peninsula...Brazoria Islands...Galveston
Island...Matagorda Islands.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Thursday morning for
the following zones: Galveston Bay...Matagorda Bay.
Gale Watch from Thursday evening through Friday morning for the
following zones: Coastal waters from Freeport to Matagorda
Ship Channel TX out 20 NM...Coastal waters from High Island
to Freeport TX out 20 NM...Waters from Freeport to
Matagorda Ship Channel TX from 20 to 60 NM...Waters from
High Island to Freeport TX from 20 to 60 NM.
Small Craft Advisory until 9 PM CST Thursday for the following
zones: Coastal waters from Freeport to Matagorda Ship
Channel TX out 20 NM...Coastal waters from High Island to
Freeport TX out 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION until 6 PM CST this evening
for the following zones: Coastal waters from Freeport to
Matagorda Ship Channel TX out 20 NM...Coastal waters from
High Island to Freeport TX out 20 NM.
Small Craft Advisory until 9 PM CST Thursday for the following
zones: Waters from Freeport to Matagorda Ship Channel TX
from 20 to 60 NM...Waters from High Island to Freeport TX
from 20 to 60 NM.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1040 PM EST Wed Feb 16 2022
.UPDATE...
Issued at 1040 PM EST WED FEB 16 2022
Freshened up the near term grids with the latest obs, but
otherwise forecast remains on track.
UPDATE Issued at 730 PM EST WED FEB 16 2022
Made tweaks to Pop and sky cover overnight, along with near term
wind gusts. Today`s wind advisory expired, so re-sent the NPW for
tomorrow`s wind headlines and updated the HWO. Updates sent to
NDFD and web servers.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 428 PM EST WED FEB 16 2022
Through 12z Thursday...
Surface high pressure off the eastern seaboard will continue to
keep warmer and drier weather across the area. The forecast area
is also located within the warm sector ahead of a cold front that
is expected to cross the area tomorrow night. As for late this
afternoon, warmer temperatures and gusty winds will be dominant.
Surface winds could reach 40 to 45 knots as a strong 850 low-level
jet moves overhead into the evening. Winds diminish slightly
overnight; however, winds are still expected to be strong.
Overnight temperatures are progged to be in the mid to upper-40s
with a few low-50s.
12z Thursday-12z Friday...
A powerful storm system will impact eastern Kentucky with strong
winds and a marginal to slight risk for severe thunderstorms late
Thursday into Thursday evening. The primary severe threat will be
damaging wind gusts, although an isolated tornado cannot be ruled
out. Outside of thunderstorms, widespread south to southwest wind
gusts of 40 to 55 mph are expected Thursday into Thursday night.
There is a possibility for stronger wind gusts near the Virginia
border.
The 16/12z model suite is generally in good agreement with the
overall large-scale pattern but there are differences in timing,
location, and strength of the smaller scale features. Rapidly
deepening low pressure will race from eastern Oklahoma Thursday
morning to eastern Maine late Thursday night. An intense warm
conveyor belt jet will feed rich Gulf moisture into the Ohio
Valley ahead of the low pressure system and its trailing cold
front.
The powerful low-level jet is highlighted by both the NAEFS and
ECWMF ENS which show 850 mb winds peaking at 70+ knots (4 to 5
standard deviations from climo) over eastern Kentucky Thursday
evening. Some of the higher res guidance shows wind speeds in this
jet reaching an incredible 80 to 90 knots. The big question
remains how much of this momentum will mix down to the surface.
Soundings continue to show weak low-level lapse rates but no
notable inversions, thus anything that can enhance vertical mixing
probably will. The BUKFIT momentum transfer remain surprisingly
weak compared to hi-res models and especially the global models,
only suggesting peak environmental wind gusts in the 30 to 45 mph
range. This may very well end up being the case for locations away
from any mechanism to overcome the weak surface stability. These
wind gusts are still strong enough for Wind Advisory -- one has
been hoisted for all of eastern Kentucky from 9 AM onward to cover
this wind potential. In our two southeastern tiers of counties,
the advisory transitions into a High Wind Watch at 4 PM. Some of
the guidance, such as the RAP13, indicate that the core of the
strong southerly jet flowing over the Cumberland Mountains may be
dynamically forced downward in the lee of Pine, Black, and
Cumberland mountains, which could lead to enhanced mechanical
mixing, downslope warming, and more efficient momentum transfer.
This was well depicted in the 12z HRRR. If this occurs,
significantly stronger environmental wind gusts are possible in
this area. A High Wind Watch has been hoisted for those counties
where this is a concern. If later guidance shows greater
confidence in this potential, all or a portion of the Watch may be
upgraded to a warning. Otherwise, later shifts will continue the
ongoing advisory for these counties.
In addition to the widespread strong winds, the powerful jet will
produce extreme amounts of 0-6 km bulk shear (60+ knots) and
storm relative helicity, but the the lack of instability should
keep the atmospheres kinematic potential from being fully
realized. Any deep convection will struggle to develop in the warm
sector before being torn apart by the excessive shear. Instead,
expect a vast majority of the convection develop along the
systems cold front (and possibly a leading prefrontal trough)
where the minimal instability will be enhanced by strong upward
forcing. Current forecasts show the leading convective line
reaching the I-75 corridor around 00z and exiting to the east in 3
to 4 hours. Any deeper convection along this line will be capable
of mixing down momentum from aloft and producing damaging wind
gusts in excess of 60 mph. While the lack of instability severely
limits the potential for sustained supercells with this
convection, the HRRR and HRW-ARW (often the best CAM for high
shear/low CAPE supercell environments) are depicting weak helicity
swaths and perhaps some transient weak supercell features. Given
0-1 km SRH values of greater than 150m2s2, a brief tornado cannot
be ruled out with stronger convection. The greatest threat for a
tornado would likely be near/north of I-64 closer to the passing
surface low.
At this point, the flooding threat appears minimal due to
extremely fast cell motions. However, an isolated minor flooding
issue cannot be ruled out under any locations that experience the
most cell training. Storm total rainfall amounts are generally
expected to range from 0.5 inch in Pike County up to 1.25 inch
west of I-75 and north of I-64. The 16/12z HREF LPMM 24-hour
precipitation plots suggest that a few isolated amounts of around
1.50 inches are possible.
Besides the wind, rain, and severe potential, Thursday will be a
very warm and windy day with temperatures warming well into the
60s to near 70 for most locations. Once the front passes Thursday
evening, winds turn northwesterly sending temperatures tumbling
to below freezing by sunrise Friday. While most of the rain will
exit with the front by midnight, lingering low-level moisture and
some forcing ahead of an approaching vort lobe will keep the
threat for rain showers transitioning to snow shower or flurries
going through the remainder of the night. Any snow accumulations
will be minor, ranging from a trace to a few tenths.
.LONG TERM...(Friday through Wednesday)
Issued at 449 PM EST WED FEB 16 2022
The models are in decent agreement with the long wave pattern
deamplifying through this weekend, before sharpening up a bit
more once again towards the end of the period. A trough axis
aligned from the Great Lakes down through the southern Plains will
cruise eastward, bringing the Ohio and Tennessee valleys a quick
shot of cold air. The flow will flatten out east of the Rockies
this weekend, before ridging amplifies across the eastern Pacific
into next week, allowing for troughing to take shape west of the
Rockies. This will set up warm and moist southwest flow across the
Mississippi Valley, allowing for a more persistent baroclinic
zone and a return to a wet and above normal temperature pattern
across the Ohio and Tennessee valleys. Details remain murky by
next week, as timing and amplitude differences is allowing for
larger ensemble spread. Overall, did favor a slower timing to the
transition, given the pattern evolution.
Mostly cloudy and cold conditions will start out across eastern
Kentucky, with ongoing cold air advection through the morning and
upslope flow and a traversing trough axis supporting some
flurries through the day. These look to diminish in the afternoon from
west to east as high pressure and its associated drier air work
in. Have stayed on the cooler side of guidance for the highs, with
mid to upper 30s expected. Mostly clear skies will build in for
Friday night, allowing for lows in the 20s, although a quickly
moving low pressure system to our north and approaching cold front
should allow for a modest ridge/valley split within the relative
warm sector. The cold front passes through dry on Saturday, with
some potentially lower relative humidity values occurring for the
weekend. As such, stayed toward the 10th percentile of the
blended guidance for dew points. Saturday highs will be closer to
seasonal, before highs return to around 60 on Sunday. Dry weather
will hold on through early Monday morning, before rain chances
ramp up thereafter with the approach of a slow-moving cold front.
Temperatures will average well above normal, with highs in the
60s and lows modifying from the 30s and 40s, to the 40s and 50s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 730 PM EST WED FEB 16 2022
VFR to start the 00Z TAF period. Southerly winds will remain
breezy with gusts of 15-20 kts overnight before ramping up again
mid-morning Thursday through the end of the TAF period. Expect
winds of 10-15 kts with gusts of 30-40 kts, especially during the
afternoon into the evening. Showers and isolated thunderstorms are
also expected on Thursday, mainly during the afternoon and
evening. Ceilings will fall throughout the day, with SYM the most
likely to fall to MVFR late in this TAF cycle.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 9 AM Thursday to 1 AM EST Friday for KYZ044-
050>052-058>060-068-069-079-080-083-084-104-106>109-111-112-114-
119.
Wind Advisory from 9 AM to 4 PM EST Thursday for KYZ085>088-110-
113-115>118-120.
High Wind Watch from Thursday afternoon through late Thursday
night for KYZ085>088-110-113-115>118-120.
&&
$$
UPDATE...CMF
SHORT TERM...GEERTSON/VORST
LONG TERM...GEOGERIAN
AVIATION...CMF
Area Forecast Discussion
National Weather Service Marquette MI
637 PM EST Wed Feb 16 2022
.SHORT TERM...(Through this evening)
Issued at 138 PM EST WED FEB 16 2022
Vis imagery and RAp analysis show a 999mb low currently approaching
James Bay from the west. Extending south of this feature is a cold
front that`s currently draped over the western UP. Ahead of the
front, lingering isentropic forcing and weak jet dynamics have
enabled an uptick in radar returns, but so far these haven`t
resulted in any obs with precip mentions. Temps so far have been
above average. The western UP have largely remained in the 20s,
while most folks in the central and east have climbed above
freezing. We`ve even observed some low 40s in Menominee and
Manistique.
As we progress through the remainder of the afternoon, colder air
will begin filtering into the region behind the front. It doesn`t
look like lake effect will get going until later this evening, so
the west should remain mostly dry. For the central and east before
the frontal passage, continued weak forcing should maintain the
change for a mix of light snow, drizzle, or freezing drizzle.
.LONG TERM...(Tonight through Wednesday)
Issued at 319 PM EST WED FEB 16 2022
Most notable item: folks should be aware of unfavorable outdoor
conditions Friday into Friday night as a disturbance passes
through and causes windy conditions. See continued discussion
below.
For tonight into tomorrow, expect generally typical U.P.
conditions for this time of year with LES within the NW to NNW
wind belts occurring. Some brief periods of -FZDZ can`t be ruled
out in eastern portions of the U.P. tonight into early tomorrow,
but otherwise the dominant wx type is expected to be of the fully
ice crystal kind, i.e. snow. LES looks to continue into tomorrow
night, especially downwind of LSZ-266 where waters remain open and
`warm.`
Friday is when weather conditions start ramping up areawide,
having the potential to impact not only outdoor activities but
travel as well. Clipper originating from British Columbia will
traverse Lake Superior Friday night, intensifying as it does so,
marching across northeastern Ontario early Saturday. The
combination of this tightening pressure gradient along with rapid
pressure rises on the backside of the exiting low will create some
rather windy conditions Friday night into early Saturday, not too
dissimilar in impacts to the event that occurred this past
Friday. Although the snow associated with this clipper will be
largely winding down as the night goes on, BLSN will become the
larger issue, contributing to reduced visbys and drifting, in
addition to any impacts as a result of the winds themselves.
Speaking of snow, a couple of widespread inches appears to be the
general consensus, with enhancement possible in the east courtesy
of Lake Michigan under the southerly flow on Friday. Upon lowpa
Friday evening/early night, snow will transition to LES in nature
under Wrly to NWrly flow.
The rest of the long-term period will be rather active, with the
pattern remaining progressive and multiple systems visiting. The
next system approaches late Saturday/early Sunday, covering at
least the northern portions of the U.P. within this time frame.
This Alberta clipper looks weaker in nature as compared to the one
just before it, but takes a similar Lake Superior path. Expect LES
again on the backside, but will merge rather quickly right into
the next disturbance.
Zonal, confluent flow takes over early next week, with attention
then turning to it setting up to be a prolonged precip period.
Mid- to upper-jet is anticipated to be flowing into the Great
Lakes region, with deamplifying upper jet axis approaching toward
the end of this forecast period. Given this setup, with NErly
surface flow prevailing, the combination of the system-based snow
looks to have Lake Superior enhancement, and with the waters
still as open as they are, could drive up accums in some places.
But, still a bit out to nail down specifics at this time.
Temperatures for this time of year are normally in the 20s for
highs and single digits for lows. With the exception of Sunday,
temps will generally be running below normal for mid-February.
However, even on Sunday, confidence isn`t incredibly high on temps
exceeding the freezing mark outside of the south-central, given
the anticipated 850mb temps and of course steady snowpack, in
addition to cloud cover moderating temps (noting that the sun`s
angle is steadily increasing this time of year and therefore
becoming more of an influence rounding out the late winter
period). Backtracking to Friday night with those aforementioned
winds, coupled with CAA, wind chills will decidedly be well below
zero everywhere, with widespread negative teens likely by early
Saturday. Stay warm.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 632 PM EST WED FEB 16 2022
Northwest winds in the wake of a cold frontal passage will
support lake effect clouds and light snow showers through the
period at all the terminals. Expect MVFR cigs to prevail at all
sites with occasional MVFR vsbys in lake effect snow, mainly at
KCMX.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 421 PM EST WED FEB 16 2022
NWrly gusts to just under gale-force will persist tonight, slowly
winding down to under 30 knots tomorrow. Srly to SWrly winds will
then ramp up Friday, with gales likely. Winds then veer NWrly
Friday night into Saturday, with high-end gales expected and
perhaps a brief period of some storm-force gusts. Winds then drop
below gales later Saturday, remaining generally below 25 knots
Saturday night well into next week.
Expect prolonged periods of heavy freezing spray throughout much
of this forecast period, dominating in the east, especially where
the waters remain `warm` and fairly open. Should have a period of
no heavy freezing spray early Friday, then again late Saturday
night into Sunday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Heavy Freezing Spray Warning from 10 PM this evening to 1 AM EST
Friday for LSZ249>251-266-267.
Heavy Freezing Spray Warning until 1 PM EST Thursday for LSZ243-
244-264.
Lake Michigan...
None.
&&
$$
SHORT TERM...JP
LONG TERM...lg
AVIATION...Voss
MARINE...lg
Area Forecast Discussion
National Weather Service Pueblo CO
637 PM MST Wed Feb 16 2022
.UPDATE...
Issued at 629 PM MST Wed Feb 16 2022
Snow is filling in across Fremont, El Paso and western Pueblo
counties along with the northeast facing slopes of the Wet
mountains. Have bumped up timing of pops for these areas. This
coincides with deepening upslope and band of frontogenesis which
is dropping southward through the evening. Intense snowfall rates
of an inch per hour can be expected over the next few hours. HRRR
also continues to advertise increasing snow accumulations over the
northern slopes of the Raton Ridge though amounts still stays
within sub advisory criteria. Will watch this area closely as 00z
runs come in for further updates. Have bumped up pops/qpf
slightly for Las Animas county which puts snow totals in the 2 to
3.5 inch range for now. Also increased pops across Baca county.
-KT
&&
.SHORT TERM...(This evening through Thursday)
Issued at 322 PM MST Wed Feb 16 2022
Key Messages:
1) Quick moving system develops widespread snowfall across south
central and southeast Colorado tonight before ending Thursday
morning.
2) Icy and snowpacked roads to impact the Thursday morning commute.
Current water vapor imagery and upper air analysis has moderate west to
southwest flow aloft across region, as a broad upper trough continues
to dig across the Intermountain West. GOES data is also indicating
stratus associated with the secondary/main cold front across
northeastern Colorado this afternoon, with MSAS data indicating
pressure falls across the plains and a meso low across eastern Las
Animas County at this time. Regional radars are indicating showers
increasing along and west of the ContDvd this afternoon, as well across
the Front Range at this time.
Tonight and Tomorrow...Models remain in good agreement of the upper
trough continuing to dig across the Rockies tonight before continuing
into the High Plains through the day on Thursday. Movement of this
system will bring increasing moisture and lift across the region, as
well as, allow for surface to h7 flow to become more north to northeast
and increase across the region tonight. This develops widespread
snowfall across the region tonight and before snow diminishes and ends
from northwest to southeast through the morning on Thursday. Latest
model runs continue to indicate a h7 frontogenetical band setting
up across the La Garita Mtns through Fremont and Teller County
this evening, which looks to enhance snowfall amounts across these
areas. With that said, have added these areas to current winter
weather advisories across the eastern mts, with snow amounts of 4
to 9 inches, along with possible local higher amounts on north and
northeast facing slopes. Have kept Northern El Paso County in a
winter weather advisory though have also added the mid Arkansas
River Valley, the Wet Mtn Valley and Huerfano County to it, with 2
to 6 inches possible through Thursday morning, and possible local
higher amounts closer to the higher terrain. Snowfall across the
rest of the higher terrain looks to range for 2 to 6 inches, with
the high mountain valleys seeing 1 to 3 inches. Snowfall across
the rest of the I-25 Corridor look to range from 1 to 4 inches
with snowfall up to 2 inches possible across the far southeast
plains.
Temperatures will cool into the teens and 20s overnight, and with
initial melting of precipitation, icy and snowpacked roadways are
expected to cause impacts for the Thursday morning commute across all
of south central and south central.
Subsident northwest flow developing across the region through the day
on Thursday will allow for snow to diminish and end from north to south
through the morning, with clearing skies through the afternoon.
Temperatures will remain below seasonal levels warming into the 30s
through the late afternoon across the plains, with highs mainly in the
20s and 30s across the higher terrain.
.LONG TERM...(Thursday night through Wednesday)
Issued at 322 PM MST Wed Feb 16 2022
Key Message...
Cold with the potential for snow Monday through Wednesday. Still
much uncertainly, but there is the potential for a significant
snow event along with unusually cold temperatures.
.Friday through Sunday...Ridge builds into the region with a
warming trend and dry weather. On Sunday, a stronger upper trough
moves into the northern Rockies with the flow aloft becoming more
westerly. Will have to watch for some spotty critical fire weather
conditions on Saturday and Sunday as minimum humidities approach
15 percent over portions of the plains. Highs on Saturday and
Sunday will reach the 60s on the plains.
.Monday through Wednesday...A series of shortwaves move into the
intermountain west with a mean trough developing over the Rockies.
There is much variability in the evolution of the system. One
camp of solutions has a further north solution for trough,
another camp is further south, and a third camp has two
shortwaves moving across the region. Timing and specifics of the
event are tough to forecast at this time. This pattern would tend
to support precipitation for the Continental Divide region. The
San Juan Mountains appear to be the most favored at this time with
southwest flow aloft being likely. Further east, cold air will
move south over the eastern mountains and eastern plains. The cold
air could reach the plains as early as Monday with solutions
showing a wide spread in the timing of the frontal passage. On
Tuesday and Wednesday, cold air will be over the region, and the
models vary on how cold it will get. Cooled the maximum
temperatures Tuesday as the EPS and GEFS means have substantial
850 mb cool anomalies. The NBM v4.1 25 percentile has highs mostly
in the teens Tuesday and Wednesday on the plains, highlighting the
potential for some quite cold air over the region. With the
upslope and the trough in the region, there is the potential for
snowfall over the eastern mountains and possibly the plains. The
NBM and ensemble means suggest the potential for a few tenths of
QPF over the eastern mountains and onto the interstate 25
corridor. However, the NBM QPF percentiles show a wide range in
QPF during this period. Some solutions suggest minimal snows in
these regions while other solutions suggest a more significant
event is possible. --PGW--
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 322 PM MST Wed Feb 16 2022
COS and PUB...VFR conditons through the early afternoon as clouds lower
and thicken as cold front continues back across the southeast plains.
Will see MVFR and IFR conditions with snow developing after 00Z at COS
and after 02Z at PUB. MVFR to low end VFR conditions expected by 10Z as
snow diminishes and ends and winds become breezy northerly 15-25Kts
with VFR conditions aft 18Z.
VFR conditions with breezy southerly winds expected at ALS through the
rest of the day. Cold front backs across the lower eastern slopes late
this afternoon, with breezy easterly winds expected to develop at ALS
after 00Z. MVFR and brief IFR conditions in snow showers expected at the
terminal through daybreak as broad upper trough moves across the
Rockies.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 AM MST Thursday for COZ065-066-
072>082-084-087.
&&
$$
UPDATE...KT
SHORT TERM...MW
LONG TERM...PGW
AVIATION...MW