Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/22/25
Area Forecast Discussion
National Weather Service Charleston SC
722 PM EST Tue Jan 21 2025
.SYNOPSIS...
A winter storm will impact our area through tonight. Another
weak storm system could clip the coast early Thursday. High
pressure will prevail for the end of the week and into next
week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
The long anticipated winter weather evening is in its early
stages, with wintry precipitation encompasses the entire
region. There is still a notable warm nose with the evening
sounding at KCHS, around 4-5C. But as deeper moisture with
increasing coverage of precipitation occurs, the warm nose will
no longer be a concern for most places. Thus the mixed
precipitation will change over to all or mostly snow, with some
mixed of freezing rain and sleet close to the coast, except for
some freezing rain in the mix over parts of coastal southeast
Georgia.
It is concerning that the HRRR and RAP show higher amounts than
now in the forecast, but there analysis of the warm nose is not
as warm. For that reason we`ll refrain from changing the snow
and ice amounts with the early evening update and monitor
trends.
There will be some potential for banding late this evening and
after midnight when the best frontogenesis is forecast to occur.
If this happens, then amounts of snow could be greater.
Lake Winds: Cold air will mix plenty of the 35-40 kt of
geostrophic winds at 1000 mb atop Lake Moultrie to hoist a Lake
Wind Advisory until 17Z Wednesday. It`s probably too long, but
makes it easier, as this coincides with the ending of the Winter
Storm Warning.
An active period is underway, with returns from KCLX entering
Jenkins County, GA and also developing along the coast of SC and
GA. These returns should initially begin as sprinkles/light rain
and likely transitioning to snow/sleet this afternoon. A Winter
Storm Warning remains in effect for the entire forecast area
from 5 PM this afternoon through Noon tomorrow (Wednesday). The
synoptic pattern features a large scale 500 hPa trough
positioned over the eastern CONUS with a 250 hPa jet located
roughly from Tennessee northeastward into the Mid Atlantic
states. At the surface a low pressure system, initially located
near the southern portion of the Florida Peninsula, will shift
northeastward a long a stalled boundary off of the southeastern
coastline. In addition to the low pressure offshore, across
inland locations high pressure will attempt to build into the
region from the west. This high pressure has ushered in an
Arctic airmass, with temperatures as of Noon today only reaching
the low to mid 30s. The moisture from the approaching low
pressure system combined with the Arctic airmass ushered in with
the high pressure sets the stage for wintry precipitation this
afternoon, evening, and into the overnight period.
With the synoptic stage set, all attention turns to the mesoscale
which will determine precipitation types and amounts. This
forecast has been particularly tricky, owing to a lingering
coastal trough in southeastern coastal GA. Initial guidance
yesterday indicated that this trough would be located near the
GA/SC border, in the vicinity of Savannah, GA. However, a hand
analysis of surface data at 12Z this morning indicates that
this coastal trough is further south than models were
indicating. This has several implications on the local forecast.
Initial guidance showed a significant warm nose at 850 hPa,
leading to a sleet forecast across coastal SC and freezing rain
chances across coastal GA. Forecast soundings this morning,
particularly the NBM and the HREF show a profile much more
conducive for snow, with little to no warm nose at 850 hPa.
Additionally, 12Z guidance has increased QPF across the entire
forecast area. Therefore snow totals have been increased with
this forecast, with generally 3 to 5 inches. Another fly in the
ointment is a possible band of 850 hPa frontogenesis that has
been persistent between model runs, located roughly along the
coastline. If this enhanced frontogenesis comes to fruition
there is the potential for higher precipitation rates and
slightly higher totals roughly from Statesboro, GA to
Summerville and Moncks Corner, SC. While thermal profiles are
more conducive for snow, sleet cannot be ruled out of the
forecast and if it occurs it will decrease the overall snow
totals. Additionally, freezing rain is still possible across
coastal southeastern GA, with amounts generally around 0.1".
Cold temperatures will remain across the forecast area through
the overnight period, with lows in the low 20s to upper 20s
along the coastal counties. A Cold Weather Advisory remains in
effect for the entire forecast area for apparent temperatures
between 10 and 15 degrees.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
A quick glance at recent guidance for max temperatures on
Wednesday, they are trending colder. Given a fresh snow cover
this seems plausible, and could result in less melting. We`ll
monitor trends, but no changes to the forecast though at this
time.
Wednesday and Wednesday night: Light snow or snow showers could
still linger for a few hours in the morning, with the best chance
along the immediate coast. The winter weather event will be over and
any additional accumulation should be very little. Clouds will clear
out and we should see quite a bit of sun. However, the presence of
snow and/or ice accumulation from Tuesday night will help keep
temperatures down. His will likely struggle to rise out of the mid
30s. The presence of 10-15 mph of northerly flow will keep wind
chill values in the upper 20s for most of the area through the day.
Temperatures will plummet during the evening before the next round
of cloud cover spreads in, especially with lingering snow/ice
on the ground. Lows in the upper teens are expected, likely
reaching those values in the late evening or early morning
hours. A Cold Weather Advisory will remain in effect.
Thursday through Friday: Model guidance continues to highlight an
offshore trough or weak wave with precipitation developing around
it. Overall, the guidance trend has been to keep this precipitation
mostly off the coast, with the potential for a few isolated showers
mainly along the Charleston County coast. Certainly the day will get
off to a very cold start, with temperatures at daybreak in the upper
teens, only warming up to around 40 in the afternoon. So, if any
precipitation were to make it onshore it is possible there could be
a period of freezing rain. However, most guidance is dry and we
continue to just have a small sliver of 20 percent chances. So, the
conclusion is that we don`t anticipate any additional winter weather
issues. Into Friday, the forecast is dry but still quite chilly.
Thursday night lows are forecast to be in the low to mid 20s with
Friday highs only in the mid 40s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
High pressure will settle across the area on Saturday and prevail
through Sunday. Temperatures should slowly moderate, with upper 40s
for Saturday followed by mid 50s for Sunday. A system could then
impact the area on Monday, though it does not look like a widespread
significant rain producer. Temperatures should continue to
slowly warm, but only back up to around normal for early next
week.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
00Z TAFs for KCHS/KJZI/KSAV: Mixed wintry precipitation and VFR
ceilings early on will give way to mostly SN/-SN the rest of the
night. As this occurs, MVFR or even IFR conditions will occur at
all terminals. Winds from the evening sounding reveal as much as
25-30 kt in the lowest 2K feet, some of which will mix down
through the night. As a result we have N winds of at least 10-15
kt with gusts around 20 kt.
Snow will taper off by daybreak and comes to end. With a
dramatic decrease in deep moisture, there will be an eventual
return to VFR by 17-18Z. It`ll continue a little gusty through
the day, but dependent upon the amount of mixing that occur.
Extended Aviation Outlook: Mostly VFR. There is a low potential
for sub-VFR conditions Thursday morning with a few showers,
mainly near KCHS and KJZI.
&&
.MARINE...
Given excellent mixing of the 50 kt geostrophic winds at 1000
mb, and as much as 40-45 kt in the mixed layer across the
Charleston County waters, we opted to raise a Gale Warning for
the waters situated out 20 nm off the Charleston County coast.
It`s certainly possible that it could be extended to include
other waters, but for now no other headline changes with the
early evening update.
Tonight: A low pressure system will be located off the
southeastern coastline while high pressure attempts to build
into the region from the west. The marine zones will become
pinched between these two features, leading to enhanced winds
and building seas. A Small Craft Advisory is in effect for all
nearshore waters for northerly wind gusts up to 30 knots. A Gale
Warning has been issued for the 20 to 60 nm offshore GA waters
for northerly wind gusts up to 35 knots. Seas across the
nearshore waters will generally be 3 to 5 with 6 to 8 ft across
the 20 to 60 nm offshore GA waters.
Wednesday through Sunday: Hazardous marine conditions will be in
progress Wednesday morning with high end Small Craft Advisory
conditions across all waters (outside Charleston Harbor). Winds and
seas will remain elevated, but gradually diminish as we head into
Thursday. Small Craft Advisories (after the ongoing Gale Warning
ends) will linger for the outer GA waters due to seas through
Thursday night, but should end for the nearshore waters Wednesday
night. Conditions will then continue to improve through the
weekend as high pressure settles in across the local waters.
&&
.CLIMATE...
Record Low Maximum Temperatures:
Wednesday, January 22:
KCHS: 31/1970
KCXM: 31/1970
KSAV: 34/1970
Thursday, January 23:
KCHS: 34/1970
KCXM: 38/2016
KSAV: 40/2016
Record Low Temperatures:
Thursday, January 23:
KCHS: 19/1985
KCXM: 24/2003
KSAV: 19/1960
Record Snowfall:
Tuesday, January 21:
KCHS: T/1984*
KSAV: 0.2/1910
Wednesday, January 22:
KCHS: T/2022*
KSAV: T/2011*
* A trace is not considered a record in terms of the daily
climate. Trace amounts shown above are more for information of
when the last instance of snow occurred on the listed date.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Cold Weather Advisory until 10 AM EST Thursday for GAZ087-088-
099>101-114>119-137>141.
Winter Storm Warning until noon EST Wednesday for GAZ087-088-
099>101-114>119-137>141.
SC...Cold Weather Advisory until 10 AM EST Thursday for SCZ040-
042>045-047>052.
Winter Storm Warning until noon EST Wednesday for SCZ040-
042>045-047>052.
Lake Wind Advisory until noon EST Wednesday for SCZ045.
MARINE...Gale Warning until noon EST Wednesday for AMZ350.
Small Craft Advisory until 1 AM EST Thursday for AMZ352-354.
Gale Warning until 5 AM EST Wednesday for AMZ374.
&&
$$
NEAR TERM...
SHORT TERM...BSH
LONG TERM...BSH
AVIATION...
MARINE...
Area Forecast Discussion
National Weather Service Des Moines IA
544 PM CST Tue Jan 21 2025
...Updated for the 00z Aviation Discussion...
.KEY MESSAGES...
- 40 to 70% chance of light snow and flurries after midnight tonight
into Wednesday
- Dry conditions with temperatures seesawing back and forth
around typical late January levels Thursday through the
weekend.
&&
.DISCUSSION...
Issued at 230 PM CST Tue Jan 21 2025
After a very cold morning with wind chills as low as 28 to 38
degrees below zero across central Iowa, this afternoon is feeling
much better with temperatures in the single digits ABOVE zero. Not
surprisingly, observations and RAP analysis shows that we have
strong warm air advection ongoing in the low levels and that
will continue into tonight with breezy winds at the surface and
in the low levels. This should result in temperatures that are
nearly steady and likely will rise overnight tonight. Beyond
temperatures, our attention turns to the northwest as GOES-East
Day Snow Fog RGB shows filaments of high clouds approaching the
state this afternoon with more substantial cloud cover over the
Dakotas. These clouds are associated with a shortwave trough
and surface low that are dropping out of Canada and will bring
the chance for light snow after midnight tonight into the day
Wednesday. Cross sections show that some level of saturation is
first achieved in the mid-levels, which propagates down into the
low level. Forecast soundings confirm this idea and also show
that moisture is somewhat limited, but with weak lift/omega and
no doubt about ice introduction, flurries or light snow should
fall for up to around 12 hours at some locations. Timing should
be after midnight over northern Iowa with snowfall slow to creep
southward reaching the I-80 corridor likely after sunrise
Wednesday. Trends over the last 24 hours have been upward
slightly in QPF and resultant snowfall over a portion of
northern Iowa, though ensemble means for more than an inch of
snowfall remain around or less than 30%. Latest 12z
deterministic guidance shows 0.10 to near 0.15 inches of liquid
along and just north of Highway 20. With snow ratios mainly of
13-16:1, an inch to an inch and a half of snowfall is expected
from around Highway 20 to around Highway 3 with lesser amounts
on either side of the `heavier` snowfall area. Latest HREF
probability matched mean largely agrees with this area, though
has a slightly larger footprint in the 1 inch area.
Much of the snowfall will taper off Wednesday evening as this
shortwave trough moves off to the southeast Wednesday night. Cold
air advection will follow it with high temperatures falling back
into the teens and low temperatures staying in the single digits
above zero. Our upper level pattern of northwest flow will evolve
with passing weak ridging and then flattening out to more zonal
flow into this weekend. This will keep the back and forth above
and below normal temperatures going through another cycle
Friday/Saturday and Sunday with milder temperatures into early
next week. No significant winter precipitation systems are on
the horizon with conditions dry in the extended forecast.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 544 PM CST Tue Jan 21 2025
VFR conditions will prevail early tonight, but low clouds and
light snow will move in during the early morning hours Wednesday
and linger through much of the remainder of the TAF period. This
will introduce periods of MVFR ceilings/visibilities, with
isolated/brief IFR possible at times. Have handled mainly with
PROB30 groups for now, but included prevailing -SN and MVFR at
FOD and ALO where probabilities are highest on Wednesday. Expect
refinement of details for the 06Z TAF issuance, and amendments
will be likely overnight and Wednesday.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
DISCUSSION...Ansorge
AVIATION...Lee
Area Forecast Discussion
National Weather Service Jacksonville FL
923 PM EST Tue Jan 21 2025
...New UPDATE...
.UPDATE...
Issued at 912 PM EST Tue Jan 21 2025
For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf
Updates so far this evening have been almost continuous with
respect to primarily temps, POPs, weather/Ptype, and snow/ice
accumulations as we continue to monitor trends and
observations/reports closely around the region.
Temps have overall been coming down a bit faster than expected,
especially near the I-10 corridor and out towards coastal Duval
where onset of rain mixing with ice pellets/freezing rain has been
bumped up (a few sites in Duval County briefly reported snow
earlier, though suspect this may have been just a brief snow/sleet
mix along with consistent rain). Some rather impressive
reflectivity and snowfall reports/obs across far interior
southeast GA also prompted a bump up in expected snowfall amounts
mostly north and west of US 84, where a general 2-4" is expected
except for locally higher amounts possible where any bands
develop/train over certain areas.
Ice accumulations are generally unchanged, with highest totals in
the 0.1-0.25" range expected across the western half of Duval
County and I-10 corridor, with a sharp cut off further south and
east. Still expecting at least a light glaze of freezing rain as
far south of northern Marion County, northwest Putnam County, and
western St. Johns County towards morning as precip gets close to
tapering off. Some sleet/snow could also mix in for these areas at
times as well, though accumulation are expected to be very
limited (under 0.5") with primarily cold plain rain expected.
Stay tuned for updates later tonight and through the morning
hours as this rare and dynamic situation continues to unfold.
&&
.NEAR TERM...
Issued at 216 PM EST Tue Jan 21 2025
For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf
Low pressure will continue to develop as it moves east across the
Gulf. The surface low will be supported by a mid/upper level
shortwave energy diving south from the upper plains phasing with a
southern stream shortwave emerging from the 4 corners region into
a strong deep trough stretching from the western Great Lakes SSW
into the lower MS valley. This trough will also create a potent
jet streak from the TN valley into the Mid Atlantic coast that
will place the right entrance region over our area, allowing
precipitation to fill in over our area by this afternoon as the
surface low moves east. With cold temperatures aloft below
freezing over interior SE GA and surface temperatures initially
above freezing, precipitation will begin as a mix of rain and snow
NW of US-84 until evaporative cooling in the column (due to dry
cold dew points in the low 20s) lowers temperatures below freezing
towards closer to sunset. South of US-84 to I-10, precipitation
will begin as rain, but change as temperatures fall to below
freezing early this evening after sunset with a mix of rain,
sleet, freezing rain falling with a mix of snow and sleet north of
the FL/GA state line. Rain will also begin to change to Freezing
rain mixed with sleet along the SE GA coast and then become mixed
with snow after midnight. Highs will reach the mid/upper 40s in SE
GA and the low/mid 50s over NE FL.
Colder temperatures will arrive late tonight as strong arctic
high pressure shifts into the upper OH valley and pushes
subfreezing temperatures south of I-10 into north central FL and
eastward to the NE FL coast down to St Augustine. This will
support rain changing over to freezing rain to locations south of
I-10 such as Gainesville and eastward to the JAX Beaches. As
temperatures fall through sunrise, freezing Rain is expected as
far south as Ocala and as far east as St Augustine before
temperatures can rise above freezing Wednesday mid to late
morning. Guidance from the HRRR and other model guidance help
support additional confidence in light icing impacts into St
Johns, eastern Putnam, and Marion county and therefore a Winter
Weather Advisory has been issued for these areas.
The Winter Storm Warning has expanded to include all of downtown
Jacksonville east to the JAX beaches and into coastal Nassau
county due to several hours of mixed precipitation and ice
accumulations of a tenth of an inch along with a half inch of
sleet/snow mix that will produce moderate impacts to travel and
utilities. The greatest potential for ice accumulations of a
quarter of an inch or higher will be west of Jacksonville along
I-10 into the Suwannee river valley where major impacts due to
icing are possible. About 1-3 inches of snow or snow/sleet will
remain NW of a line from Homerville to Waycross to Everett.
Lows will fall to the mid 20s over SE GA and the upper 20s over
NE FL along I-10 west of Jacksonville with lows 30-32 along the NE
FL coast as far south St Augustine and SW to Palatka and Ocala.
Brisk northerly winds 10-20 mph with gusts to 35 mph along the
coast will deliver very cold wind chills Wednesday in the early
morning hours with wind chill values in the upper teens over SE GA
and the low/mid 20s over all of NE FL and a cold Weather Advisory
has been issued for these very cold conditions through 10AM
Wednesday.
&&
.SHORT TERM...
(Wednesday through Thursday night)
Issued at 216 PM EST Tue Jan 21 2025
Wednesday... Dangerous travel conditions will linger through the
day on Wednesday, with any ice accumulation having a hard time
thawing. Most areas in inland SE GA will not hit 40 degrees
despite mostly sunny skies, with most of northeast Florida only
reaching the lower to upper 40s. Low temperatures will drop into
the 20s for all of SE GA, and most of inland NE FL, with only
areas along and east of the St. Johns river basin, and Marion
county, staying above freezing. Wind chills will likely fall into
the upper teens to 20s for most of the area, and Cold Weather
Advisories may be necessary for some locations. There is a slight
(20-30%) chance of precipitation Wednesday night for the NE FL
coast, for now that area coincides with above-freezing
temperatures.
Thursday... Another cold day forecast, with high temperatures only
in the 40s other than a few locations in Flagler and Marion
reaching the low 50s. Showers remain possible through the day for
NE FL and the SE GA coast, with things tapering off around sunset
before yet another freezing night. Lows will be in the 20s for SE
GA and most of NE FL, with high potential for a hard freeze and
Cold Weather Advisories.&&
.LONG TERM...
(Friday through next Tuesday)
Issued at 216 PM EST Tue Jan 21 2025
It will stay chilly on Friday and Saturday, with highs in the 40s
to 50s across the area, with luckily no precipitation chances.
Friday night will be brutally cold, with low temperatures dropping
down into the low 20s across inland SE GA, mid to upper 20s
across the SE GA coast and inland NE FL, and low 30s near the St.
Johns river basin and NE FL coast. These lows promote hard freeze
conditions for most inland areas, but with calm winds, wind chills
will hover just above Cold Weather Advisory criteria for SE GA at
this time, however inland NE FL is forecast to fall below the
threshold of 25 degree wind chills. Temperatures will be a tad
warmer Saturday night, but it is still likely to fall below
freezing for inland southeast Georgia and the Suwannee valley.
Highs Sunday and Monday will finally reach the 60s, with low
temperatures staying above freezing area-wide.
&&
.AVIATION...
(00Z TAFS)
Issued at 609 PM EST Tue Jan 21 2025
Restrictions in stratus are expected throughout this TAF period.
Precipitation will result in visibility restrictions through the
night into Wednesday morning. The lowest restrictions are expected
in any snow showers.
A wintry mix of precipitation types is expected throughout the night
for all sites, but KSGJ. The wintry mix is only expected to affect
KSGJ for a few hours around sunrise Wednesday. The precipitation
is expected to move southeast of area TAF sites a few hours after
sunrise on Wednesday.
Winds will be elevated and gusty especially at the coast.
&&
.MARINE...
Issued at 216 PM EST Tue Jan 21 2025
An inverted trough developing over the coastal waters bring
increasing chances for precipitation for area waters throughout
the day, reaching 60-70% chances by this evening. High pressure
will be situated to the northwest today, as low pressure moves
southeast across the Gulf, increasing northerly winds out over the
the local waters. A broad ridge of high pressure will extend down
the southeastern US coast Wednesday afternoon through Wednesday
night. A trough of low pressure will be just east of the region
Thursday into Friday with high pressure to the west. High pressure
will build over the southeastern US Saturday.
Rip Currents: High rip current risk at all area beaches today
through Wednesday night.
&&
.CLIMATE...
Issued at 505 AM EST Tue Jan 21 2025
Below are the record lowest maximum temperatures and minimum
temperatures.
Climate sites are Jacksonville, FL (JAX), Craig Airfield, FL (CRG),
Alma, GA (AMG), and Gainesville, FL (GNV).
DATE | SITE | Record Low Max | Record Low
------------------------------------------
------------------------------------------
1/21 | JAX | 30 (1985) | 7 (1985)
CRG | 30 (1985) | 9 (1985)
AMG | 42 (2016) | 20 (2011)
GNV | 29 (1985) | 10 (1985)
------------------------------------------
1/22 | JAX | 41 (2022) | 16 (1985)
CRG | 47 (1985) | 18 (1985)
AMG | 40 (2022) | 16 (1985)
GNV | 46 (2022) | 17 (1985)
------------------------------------------
1/23 | JAX | 45 (1960) | 25 (2011)
CRG | 48 (2003) | 28 (2011)
AMG | 42 (2016) | 20 (2011)
GNV | 48 (1987) | 23 (1960)
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 23 33 21 39 / 100 0 10 0
SSI 26 38 30 43 / 100 40 10 10
JAX 25 40 30 47 / 90 40 10 20
SGJ 30 46 38 50 / 90 80 20 30
GNV 25 42 32 47 / 90 40 10 20
OCF 29 48 34 51 / 90 50 10 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Winter Storm Warning until 1 PM EST Wednesday for FLZ021-023-024-
030-031-035-120-124-125-132-136-220-225-232-236-237-322-325-
422-425-522.
Cold Weather Advisory until 10 AM EST Wednesday for FLZ021-023-
024-030-031-033-035-038-120-124-125-132-133-136>138-140-220-
225-232-236-237-240-322-325-340-422-425-522.
Freeze Warning until 10 AM EST Wednesday for FLZ021-023-024-030-
031-033-035-120-124-125-132-133-136-137-140-220-225-232-236-
237-240-322-325-340-422-425-522.
Freeze Watch from Wednesday evening through Thursday morning for
FLZ021-023-024-030-031-035-120-124-136-220-225-232-236-322-
422-425-522.
Winter Weather Advisory from 1 AM to 10 AM EST Wednesday for
FLZ033-133-137-140-240-340.
High Rip Current Risk through late Wednesday night for FLZ124-
125-133-138.
Wind Advisory until 10 AM EST Wednesday for FLZ125-133-138.
High Surf Advisory until 7 PM EST Wednesday for FLZ133-138.
GA...Winter Storm Warning until 1 PM EST Wednesday for GAZ132>136-149-
151>154-162-163-165-166-250-264-350-364.
Cold Weather Advisory until 10 AM EST Wednesday for GAZ132>136-
149-151>154-162-163-165-166-250-264-350-364.
Freeze Warning until 10 AM EST Wednesday for GAZ132>136-149-
151>154-162-163-165-166-250-264-350-364.
Freeze Watch from Wednesday evening through Thursday morning for
GAZ132>136-149-151>154-162-163-165-166-250-264-350-364.
High Rip Current Risk through late Wednesday night for GAZ154-
166.
AM...Small Craft Advisory until 4 PM EST Thursday for AMZ450.
Gale Warning until 10 AM EST Wednesday for AMZ452-454-470-472-
474.
&&
$$
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
904 PM CST Tue Jan 21 2025
.KEY MESSAGES...
- Wind chills of -15F to -20F will persist through this evening.
The Cold Weather Advisory remains in effect until midnight.
- Accumulating snow (locally up to 1") is expected Wednesday
through early Thursday morning leading to slippery travel.
- Lake effect snow may linger across northeast Porter County
during the day on Thursday.
&&
.UPDATE...
Issued at 904 PM CST Tue Jan 21 2025
This evening, a meridionally-oriented warm front extends down
the spine of the Plains with a broad region of efficient low
level warm advection out ahead of it overspreading western
portions of the Midwest. This warm advection is driven by a
southwesterly low level jet ahead of the front that will be
intensifying through the night before moving over our CWA. This
system will bring light to moderate snow to parts of the area
tomorrow, beginning in the morning with this warm advection
regime. It`s a consistent and agreed-upon signal that the snow
probs during the morning and afternoon tomorrow will be focused
toward the nose of the 925mb jet, which translates to areas
mainly north of the I-88 corridor and up into southern WI as low
level moisture may remain scarce farther south. This is the
pattern we`re seeing upstream as the only snow currently being
reported along this jet is found way up in MN. The RAP and NAM
have been wanting to bring some snow near and north of I-80 and
across much of the Chicago metro during the day tomorrow, but
they are notably more saturated than other camps. If snow does
fall on areas south of I-88 during the daytime, the best chances
appear to be the during the morning before some additional dry
air looks to wedge into the area for the afternoon.
Snow coverage should begin to expand southward late in the day
with the approach of the upper wave, although most guidance
keeps snow out of the Chicago metro until after dark. Snow
chances will be pushed off to the east by the cold front early
Thursday morning. There remains a bit of discrepancy regarding
coverage and intensity owing to differences in moisture and
forcing. But the going forecast for a few tenths to around a
half an inch across much of our CWA still looks good with
locally higher amounts to around an inch north of I-88.
Additionally, we`re still expecting a good push of wind tonight
through early tomorrow afternoon with that low level jet moving
over. Gusts in the 30 to 35 mph range are expected into early
afternoon with some up to near 40 mph possible. A few sites out
in Eastern IA are already gusting to 25 to 30 mph on the leading
edge of the jet. Winds will gradually subside during the
afternoon and evening. Only minor tweaks were made to the going
forecast and updated products have been sent.
Doom
&&
.DISCUSSION...
Issued at 304 PM CST Tue Jan 21 2025
Through Wednesday Night:
An arctic high continues to slide across the Midwest and Great
Lakes this afternoon which has resulted in bitterly cold
temperatures despite the nearly unabated sunshine. Highs today
have leveled off around 0 degrees and look to remain nearly
stationary through sunset. With winds expected to remain breezy
through this evening, wind chills in the -15F to -20F range are
expected to prevail through midnight. Therefore, the Cold
Weather Advisory was extended until midnight to highlight this
threat.
After midnight, temperatures are expected to gradually warm as
strong south-southwest winds develop and advect in "warmer" air.
However, temperatures are still expected to be in the single
digits through the night with wind chills hovering in the -10F
to -15F range. Since these wind chill magnitudes are above the -20F
threshold used for advisories, the expectation is for no
additional cold weather headlines to be issued once the
aforementioned one expires. Though wind gusts will be increasing
into the 20-25 mph range overnight which will keep a notable
chill in the air to start our Wednesday.
The broad shortwave trough currently in Alberta will be
pivoting into the northern Plains and eventually the Great Lakes
through the day on Wednesday. As this occurs, the surface low
ahead of the system will be pivoting into the northern Great
Lakes which will force a cold front to advance across the Upper
Midwest Wednesday morning. Snow is expected to develop beneath
this wave and along the cold front and begin to move into far
northern IL towards the mid-morning and early afternoon hours.
However, the front is forecast to get hung up near the IL-WI
line which should keep the bulk of the snow along the state line
and points north through much of the day. Though, the front is
expected to pivot southward through the rest of the area late
Wednesday afternoon and evening as the shortwave dives into the
Ohio River Valley. Since the front should be fairly progressive
as it moves across northern IL and northwest IN, the duration of
snow at any one location should be only 3-4 hours at most and
thus keep accumulations around half an inch. However, locally
higher totals up to an inch are possible especially near the IL-
WI line where longevity is forecast to be maximized.
Regardless, the cold surface temperatures will allow for some
snow covered roads and slippery travel so be sure to use caution
if traveling tomorrow.
Snow is expected to gradually taper after midnight Wednesday
night, though some lingering light snow and flurries may persist
into Thursday morning for areas east of I-57. Otherwise, expect
temperatures to warm into the 20s Wednesday afternoon before
cooling into the teens Wednesday night. Winds will also be gusty
on Wednesday as the system moves through with gusts in the
25-30 mph range likely and locally higher gusts possible. Though
winds will subside Wednesday evening as the system begins to
exit to our east.
Yack
Thursday through Tuesday:
Snow will be winding down toward daybreak on Thursday though a
few flurries may linger near/southeast of I-55 through mid
morning. Conditions become favorable for lake effect snow
oriented into northeast Porter County during the day on Thursday
(northwesterly fetch, increasing inversion heights, steep lapse
rates and saturation through the DGZ) which could result in
additional accumulations (locally up to 0.5-1") and continued
slick travel. Cloud depths begin to thin toward Thursday evening
with the main area of snow shifting further east.
Winds will be breezy out of the northwest in the wake of a cold
frontal passage Thursday morning which combined with
temperatures only warming into the upper teens to lower 20s will
result in wind chills in the single digits persisting during
the day. Low temperatures Thursday night drop into the single
digits once again areawide with wind chills in the 0 to -10
degree range. More of the same is expected on Friday with highs
in the lower 20s. A return to southwesterly flow Friday night
should allow temperatures to slowly rise through the night with
temperatures on Saturday currently forecast to briefly warm
above freezing (33-36F) in the afternoon.
While there remains variability in the handling of the upper
level pattern into early next week, the general expectation is
for an elongated positively tilted upper level trough
(potentially cut-off low) to develop across the western CONUS
with quasi-zonal flow extending east. This pattern largely
favors keeping more moisture laden weather disturbances largely
south of the area and is supported by the latest ensemble
guidance keeping probs for >0.1" of precipitation generally
under 20% through early next week.
Petr
&&
.AVIATION /00Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 539 PM CST Tue Jan 21 2025
Aviation Forecast Concerns for 00Z TAFs:
- Brief lull in winds this evening, then becoming breezy again
from the southwest late tonight and Wednesday with gusts ~25
kts.
- Period of light snow possible Wednesday morning across far
northern IL/southern WI, Lower probability for Chicago
terminals, greater for KRFD. MVFR/brief IFR possible.
- Another more likely potential for a period of light snow
Wednesday evening. IFR/low-MVFR possible.
Weak surface high pressure ridge was passing south of the
terminals early this evening, with decreasing winds backing to
the southwest. These southwest winds are expected to increase
again after midnight tonight, with gusts around 25 kt developing
and persisting into the day Wednesday. Winds will then ease
gradually Wednesday evening.
Clear skies across the region this evening will eventually give
way to increasing mid-level VFR cloud cover overnight, in
response to a strengthening low level jet and associated warm
advection (especially aloft) ahead of an approaching upper level
trough. Saturation in response to this forcing will result in
VFR cloud bases continuing to lower Wednesday, with some
potential for an area of light snow to develop from IA into WI
and potentially far northern/northwest IL during the morning.
Confidence is somewhat low in the south/southeastward extent of
the snow potential, as various model guidance shows considerable
spread in the degree of saturation in lower levels. KRFD has
the highest probability of seeing snow during the morning, with
decreasing likelihood farther southeast into the Chicago area. A
lull is then expected by midday especially for the Chicago
terminals.
A better potential for light snow looks to come later in the
day/evening across the area, as the main upper level trough
moves through. Have indicated a period of prevailing light snow
after 22Z at KRFD and after 00Z in the KORD/KMDW 30-hour TAFs,
along with a prob mention of IFR conditions in the 02Z-06Z
period. Given relatively cold temperatures, some accumulation
is likely (generally less than an inch) with both the potential
morning and evening periods of light snow.
Ratzer
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Cold Weather Advisory until midnight CST tonight for ILZ003-
ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-ILZ011-ILZ012-ILZ013-
ILZ019-ILZ020-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039-ILZ103-
ILZ104-ILZ105-ILZ106-ILZ107-ILZ108.
IN...Cold Weather Advisory until midnight CST /1 AM EST/ tonight
for INZ001-INZ002-INZ010-INZ011-INZ019.
LM...Small Craft Advisory until 6 PM CST Wednesday for the IL and
IN nearshore waters.
&&
$$
Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Melbourne FL
918 PM EST Tue Jan 21 2025
...New UPDATE...
.KEY MESSAGES...
Issued at 915 PM EST Tue Jan 21 2025
- Cold rain continues tonight, with shower activity decreasing
Wednesday afternoon.
- Windy, especially along the coast, with a period of Gale
conditions spreading rapidly southward into Wednesday morning.
High, pounding surf and beach erosion near the time of high tide
overnight, especially Cape Canaveral northward.
- Even colder low temperatures forecast late this week but
increased sunshine this weekend.
&&
.UPDATE...
Issued at 915 PM EST Tue Jan 21 2025
An impressive pressure gradient (noted by RAP analysis) has
settled across much of east central Florida tonight, while
scattered shower activity persists. Winds of 15 to 25 mph are
gusting as high as 30 to 40 mph at times, especially closer to the
coast. This surge of northerly winds will continue southward
overnight with higher gusts reaching the Brevard and Treasure
Coasts. A Wind Advisory remains in effect through 9 AM for all of
the east central Florida coast.
With windy conditions spilling south a few hours earlier than
previously modeled, wind chill values have tumbled into the 30s
from the Orlando metro area northward. As of 9 PM, Deland was
reporting a wind chill of 30 degrees, with Leesburg at 31 degrees,
and Orlando at 37 degrees. Temperatures in those locations are
still in the upper 30s to mid 40s, so a 7-10 degree spread in the
observed temps and apparent temps is occurring. In general, the
timing of the Cold Weather Advisory (starting at 1 AM) is in good
shape. However, trends will be monitored over the next couple of
hours to determine if colder wind chills are realized a bit
faster.
This forecast update brings overnight low temperatures more in
line with recent guidance and observed trends. Temperatures may
approach the 32 degree mark across extreme northern Lake and
Volusia counties by sunrise, with most other locations across
those counties reaching the mid to upper 30s. Farther south, from
Orlando and interior Osceola/Okeechobee counties to the Space
Coast, temperatures will range from the mid/upper 30s to mid 40s.
Expect temps in the upper 40s to mid 50s closer to the coast,
especially from Sebastian southward along the Treasure Coast.
&&
.PREVIOUS DISCUSSION...
Issued at 400 PM EST Tue Jan 21 2025
Tonight...A brief lull in showers this afternoon will be short
lived, with short range guidance hinting at increasing coverage
once again overnight. The frontal boundary is draped across south
Florida this afternoon, with a plume of moisture north of the
boundary keeping central Florida under cloudy skies and showers
into the overnight period. Lightning activity is still not
forecast with these showers.
A surge of northerly winds moving from the north towards the
south across east central Florida will lead to winds increasing to
10 to 20 mph, with gusts to 30 to 40 mph possible. A Wind
Advisory goes into effect at 5 PM along the Volusia and Brevard
coasts, and expands to southern Brevard and the Treasure Coast at
midnight. These increasing winds will cause an increase in seas as
well, with high, pounding surf expected to develop particularly
north of the Cape. A High Surf Advisory was issued from 7 PM
tonight to 7 AM Wednesday for breaking waves of 8 to 10 feet for
the Volusia and northern Brevard coasts. It is also worth noting
that high tide occurs at 1:30 AM, which will further enhance the
potential for some beach and even dune erosion. Southward,
breaking waves of 4 to 6 feet overnight will be possible, though
it will be short lived and confidence in erosion is not as high.
In addition to the rain and wind concerns, cold temperatures are
forecast overnight, with lows generally in the mid to upper 30s
near and north of the I-4 corridor, and in the 40s southward. Some
spots along the Treasure Coast are forecast to fall into the low
50s. Wind chill values north of the I-4 corridor are forecast to
fall into the mid 20s to low 30s, and as a result, a Cold Weather
Advisory has been issued from 1 AM to 9 AM for Lake, Volusia,
Seminole, and Orange counties.
Wednesday-Thursday...The unsettled weather pattern is forecast to
persist over the next couple of days as the frontal boundary
remains draped across south Florida. A plume of moisture north of
the boundary and draped across central Florida will cause persistent
shower activity Wednesday and Thursday, with rain chances
remaining between 40 to 70 percent. Cloud coverage also remains
high as a result of the moisture, so it may be a few days until
the Sunshine State actually sees some sunshine. Lightning activity
is not expected with these showers. Model guidance is hinting at
some diminishing rain chances Wednesday night, but kept a 20 to 30
percent chance in across the area for now. Another weak wave of
low pressure is forecast to ride along the boundary Thursday,
eventually dragging the front away from the area Thursday night
into early Friday. Rain chances diminish Thursday night across the
peninsula as an area of high pressure begins to slowly build in
across the peninsula, with some lingering activity possible across
the local Atlantic waters.
Cooler temperatures are forecast to persist across the area over
the next couple of days, with afternoon highs generally in the 50s
and some low 60s possible along the Treasure Coast. Wednesday
night, lows in the 40s across much of the interior and in the 50s
along the coast south of the Cape and across the Treasure Coast.
Cooler on Thursday night, with lows in the 30s across much of the
interior and in the low to mid 40s along the coast south of the
Cape and near Lake Okeechobee. Wind chills in the upper 20s to mid
30s Thursday night.
Friday-Tuesday (previous modified)...Significant drying is forecast
to overspread the area Friday through Saturday with the coldest
temps forecast for this week. Widespread 30s is forecast by Saturday
morning with low to mid 40s limited to the immediate Treasure Coast.
Despite increasing sunshine, maximum temperatures may still hold in
the upper 50s across Lake and Volusia counties with low to mid 60s
elsewhere. But a warming trend appears in the cards as high pressure
tracks east into the Atlantic off the Carolina coast Sunday, veering
the local winds onshore and finally losing the north wind component.
Dry conditions are forecast to prevail through the remainder of the
weekend and into early next week. Lows Sunday morning in the 40s and
50s, rising to the low to mid 70s, and a couple/few degrees warmer
on Monday and Tuesday.
&&
.MARINE...
Issued at 915 PM EST Tue Jan 21 2025
Hazardous to dangerous boating conditions are forecast across the
local Atlantic waters over the next few days. Gale conditions are
developing tonight as a surge of northerly winds moves southward
across the waters, causing seas to quickly build to 9 to 14 feet.
Winds diminish into Wednesday, but seas will remain hazardous over
the next few days. An increase Thursday afternoon in northerly
winds to around 20 knots and persistent seas across the Gulf
Stream will keep conditions hazardous on Thursday.
As a result of these conditions, a Gale Warning is in effect
through 5 AM Wednesday across the Volusia and Brevard waters, and
will transition to a Small Craft Advisory after 5 AM tomorrow
morning, continuing through at least Thursday evening. A Small
Craft Advisory goes into effect (slightly sooner) at 10 PM
tonight for the Treasure Coast waters, and continues through at
least Thursday evening. Extensions to the Small Craft Advisory may
be needed for all legs of the local Atlantic waters.
In addition to the hazardous to dangerous boating conditions,
numerous to widespread shower activity is forecast to persist
across the local Atlantic waters tonight through Thursday.
Conditions begin to dry out on Friday, with boating conditions
still remaining poor through Friday. By Saturday, winds and seas
are forecast to diminish, and a return to favorable boating
conditions is likely Sunday into early next week.
&&
.AVIATION...
(00Z TAFs)
Issued at 656 PM EST Tue Jan 21 2025
IFR conditions prevailing tonight, lifting to MVFR by mid morning
across the interior and by early afternoon along the coast. Increasing
coverage of showers this evening into tonight, with SHRA and -SHRA
prevailing across all TAF sites through tonight, ending across the
interior sites around 14Z and along the coast by around 16Z.
Occasional reductions to LIFR will be possible with these showers,
but confidence in timing continues to be low. Northerly winds
persist through the TAF period, with winds increasing this
evening to 15-20 KT with gusts 25-30 KT. Winds will remain
elevated through the TAF period, with speeds decreasing to 10-15
KT with gusts 20-25 KT by early evening on Wednesday. The
strongest winds look to be along the coast from the Space Coast
northward (DAB/TIX/MLB).
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 39 52 45 55 / 90 70 30 40
MCO 40 53 46 54 / 80 60 20 40
MLB 45 60 50 61 / 80 80 30 50
VRB 49 63 54 65 / 70 80 30 50
LEE 36 50 40 52 / 90 60 20 30
SFB 39 52 45 55 / 90 70 20 40
ORL 39 52 45 54 / 80 70 20 40
FPR 49 62 54 65 / 70 70 30 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...High Surf Advisory until 7 AM EST Wednesday for FLZ141-347-447.
Wind Advisory until 9 AM EST Wednesday for FLZ141-347-447-647-
747.
Wind Advisory from midnight tonight to 9 AM EST Wednesday for
FLZ154-159-164.
AM...Gale Warning until 5 AM EST Wednesday for AMZ550-552-570-572.
Small Craft Advisory from 5 AM Wednesday to 7 PM EST Thursday
for AMZ550-552-570-572.
Small Craft Advisory until 7 PM EST Thursday for AMZ555-575.
&&
$$
UPDATE...Schaper
AVIATION...Watson
Area Forecast Discussion
National Weather Service Marquette MI
641 PM EST Tue Jan 21 2025
.KEY MESSAGES...
- Arctic air begins to modify tonight. Minimum temperatures of
-5 to 15F will occur this evening, then temperatures will
slowly rise. Cold weather advy for low wind chills remains in
effect across the entire forecast area until 06z tonight.
- Moderating airmass will see temperatures trending more or
less towards normal values from midweek onwards.
- Passing clipper systems will bring in rounds of light lake
effect/enhanced snow through the extended period, but
widespread significant snowfall is not expected.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 337 PM EST Tue Jan 21 2025
Water vapor imagery and RAP analysis show mid-level ridging just off
of the W Coast extending into AK/nw Canada and a deep trof over
eastern N America. This pattern has forced arctic air into the
central and eastern U.S. The troffing is beginning to relax now as
waa is spreading across the Plains in response to a shortwave
dropping thru Alberta/Saskatchewan. Another shortwave is dropping s
toward northern Manitoba. Closer to home, low-level winds have
already backed to the sw, shifting all Lake Superior LES offshore of
Upper MI. Despite sunny skies, temps only range mostly thru the
negative single digits F across much of the fcst area at 20z. Some
locations across the e have pushed just above 0F.
WAA/isentropic ascent will strengthen into the Upper Great Lakes
tonight in response to the aforementioned waves. Per 275/280/285k
sfcs, 30-40kt winds become oriented nearly perpendicular to the
isobars, but pres steadily rises on those sfcs, indicating that not
all of the advection is going into lift. Combined with a lack of
moisture, not expecting much snow to develop in this waa/isentropic
ascent regime. Fcst reflects mostly a 30-60pct chc of -sn beginning
w near midnight and spreading eastward overnight. Winds should back
just enough to bring some lake enhancement off of Lake MI into far
se Schoolcraft County and se Luce County by 12z. Snow accumulations
will be less than 1 inch with paltry moisture avbl (mixing ratios
around 1g/kg in roughly the 700-750mb layer).
Min temps ranging btwn -5 and -15F will occur this evening before
clouds increase/thicken and low-level winds increase further,
resulting in temps slowly rising. The cold conditions along with
wind support cold weather advy thru the evening hours. The 06z end
time for the advy appears ok for now as slowly rising temps result
in apparent temps crossing advy criteria threshold over much of the
area at around that time.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 257 PM EST Tue Jan 21 2025
A more active pattern looks to set up for the midweek and beyond as
the first in a series of shortwaves transits through the Midwest
region on Wednesday. While details in timing and intensity of the
following shortwaves is still high, there is a general agreement on
a brief period of local ridging for Friday before another shortwave
passes Friday into the weekend. From there, more shortwaves (with
plenty of spread among models, and varying degrees of
strength/timing) are expected through the rest of the period. These
are embedded in broad troughing over the Great Lakes as a split flow
pattern sets up with a cutoff low over the Desert Southwest.
Wednesday morning, a weakening clipper low will be moving along the
border of northern MN, set to track along/north of Lake Superior
through the afternoon. High pressure extending fro the Mid Atlantic
southwest to Texas will cut us off from the Gulf of Mexico (and its
much-needed moisture), and given prior similar setups in moisture-
starved clippers this season, only a couple to a few tenths of
snowfall are expected with this system as it passes Wednesday. One
feature to watch with the Wednesday system is any potential
southerly to southwesterly lake effect/enhanced snowfall as despite
the relatively warm advection, 850mb temperatures are still expected
to be in the negative teens above an open Lake Michigan. CAMs
continue to show stronger banding extending into Mackinac and
Chippewa counties, just east of our CWA. However, if future forecast
cycles shift this more westerly, at least Luce county could be
clipped by some advisory amounts.
Otherwise, mainly light northwesterly lake effect snowfall is
expected in the wake of the trough`s passage with LREF 6-hourly
precip rates for Wednesday evening through Thursday are only around
0.01-0.05", and some locally higher amounts up to 0.10" Wednesday
night where any localized terrain enhancement can occur in the
western UP. Will also note that some of the latest CAM guidance is
hinting at some locally higher amounts in the eastern UP Wednesday
evening/night with some localized convergence or meso-low
development moving onshore from eastern Lake Superior. With snow
ratios only peaking at around 20:1, around an an inch of snow per
six hours is expected for the most part across the NW wind snow
belts Wed-Thurs, with locally higher amounts to 1-2in/6hrs Wednesday
evening and night in those areas of localized enhancement. Into
Thursday, slowly backing winds and a drier airmass working in as a
ridge slowly builds into the Great Lakes will cut back on snowfall
accumulations throughout the day.
Meanwhile, temperatures continue to come in slightly below average
Wednesday through Thursday, but more seasonable air is expected to
return to the area late week with highs generally in the teens and
20s and lows in the single digits. As long as Lake Superior remains
in its current mainly ice-free state, temperatures aloft continue to
support lake effect snow in the wake of any passing shortwaves. For
the weekend and beyond, the most common 925mb wind direction remains
NWerly, so that will continue to be the expected regime for LES
bands to set up in following any clippers. However, strong synoptic
snows look unlikely until at least next week, when there`s a weak
signal in the ensembles for a sub-900mb low to pass...somewhere
through or near the Great Lakes. Spread is high at this time period,
so this prospective system is just as likely to miss the UP as it is
to provide any winter impacts. CPC outlooks for early February
highlight slight favoring of cooler than normal temperatures and
higher precipitation than normal for the Upper Great Lakes region.
This likely stems from ensemble mean 500mb height charts favoring
troughing stretching from northeast Canada to the Great Lakes and
ridging over western North America, favoring transport of cooler air
over still-open waters of the Great Lakes (save for bays, etc that
are icing over currently) which should support continued LES.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 641 PM EST Tue Jan 21 2025
VFR conditions will fall to MVFR tonight as a weak system moves
through the region, spreading a chance of snow to all terminals late
tonight into Wednesday morning. Visibilities may fall to IFR at KIWD
and KCMX. Gusty southwesterly winds of 20-25 kts are also expected
overnight as the system moves through. Late in the period, lake
effect snow will be possible at KCMX/KIWD.
&&
.MARINE...
Issued at 257 PM EST Tue Jan 21 2025
For today, westerly winds will back southwesterly ahead of an
approaching clipper low. A few isolated gale force gusts are
expected late this evening through tonight, especially across the
west half of the lake, but confidence of more widespread coverage at
any given time is too small to issue a Gale Warning. An approaching
clipper low on Wednesday will bring southwesterly wind gusts up to
near 30 kt, veering to the NW overnight, with chances of gales of
around 30-50% Wednesday to Wednesday night across the eastern half
of the lake. As high pressure influences the forecast for Thursday,
mainly westerly winds around 20-25 kt are expected. For Friday into
the weekend, primarily westerly and southwesterly winds around 25 kt
are expected, but gales to 35 knots are possible into early Sunday
(around 30-50% chance) as winds shift to the NW again behind a
passing clipper system. NW winds remain elevated at around 20-30kts
into early next week. With some of the most frigid air of the last
few years over Lake Superior, Heavy Freezing Spray Warnings are in
effect through at least Wednesday morning as waves of up to 10 feet
feet will allow for supercooled spray to form.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Cold Weather Advisory until 1 AM EST /midnight CST/ Wednesday
for MIZ001>007-009>014-084-085.
Lake Superior...
Heavy Freezing Spray Warning until 7 AM EST /6 AM CST/
Wednesday for LSZ162-240>251-263>265.
Heavy Freezing Spray Warning until 1 PM EST Wednesday for
LSZ266-267.
Lake Michigan...
Heavy Freezing Spray Warning from 4 AM to 1 PM EST Wednesday
for LMZ248-250.
&&
$$
SHORT TERM...Rolfson
LONG TERM...LC
AVIATION...JTP
MARINE...LC