Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/27/24
Area Forecast Discussion
National Weather Service Gaylord MI
1141 PM EDT Tue Mar 26 2024
.KEY MESSAGES...
- Windy into Wednesday and becoming much colder. Rain changes to
light snow showers.
- Light mix of rain/snow early this weekend.
&&
.UPDATE...
Issued at 934 PM EDT Tue Mar 26 2024
Deep low pressure working its way steadily northeast across
central Lake Superior this evening, with its attendant
cold/occluded front set to exit into northern Lake Huron. Exit
of this front has taken most organized area of showers east
along with it. Increasing post-frontal low level moisture
advection within maturing surge of cold air advection is kicking
off some very light showers/sprinkles into the western half of
the area. Expect this general idea to continue, with continued
cooling allowing a gradual switchover to snow by sunrise
Thursday. Minimal lake contributions and lack of deeper
moisture/forcing will keep any amounts limited, with just
perhaps a dusting of snow in places. Gusty southwest winds will
continue tonight, at times gusting in excess of 35 mph.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Pattern/Synopsis: 988mb low pressure is over western upper MI,
tracking ne. The warm front has lifter clear of eastern upper
MI, while a wavy cold front is pushing into ne lower WI and sw
lower MI.
Forecast: Showers continue to lift northward into nw lower MI.
The nearest lightning activity is east of MKG, though central
Newaygo Co had a bit an hour ago. The mesoanalysis page from SPC
shows an axis of circa 250j/kg of SbCape, from central IN up to
about TVC. This reflects the richer airmass moving in, with
surface dew points around 50f in nw lower MI, along with some
cooling aloft. Wind fields and shear remain strong, and our
winds will be gusty thru tonight. Convection /could/ bump up
winds to strong/svr levels in isolated spots, via downward
momentum transfer. HRRR runs continue to show some further
organization/consolidation of convection into this evening. Will
be keeping an eye on radar trends into late evening, by which
time stronger convection will exit across Lk Huron.
High pops with fropa after 00Z are confined to ne lower/eastern
upper MI. A wraparound tongue of moisture (now in western WI)
will lift ne-ward with the larger system. That may scrape by nw
lower MI tonight, but will mainly impact eastern upper MI with
likely precip. By very late tonight though, all deeper moisture
will depart, and we will be left with chance for light lake
effect precip in nw lower and eastern upper MI.
Much colder air returns to the area tonight. 850mb temps will
tumble to at or below -10C by Wed morning in the west half of
the area. Precip this evening will remain liquid, but toward and
especially after midnight, leftover precip will turn to snow
from w to e. This isn`t expected to result in more than a thin/
crusty coating of snow anywhere, though some wet roads could
turn icy before than fully dry out.
Min temps mid 20s to lower 30s. Winds gusting to 30-40mph. Wind
chills in the teens at daybreak.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
Pattern Synopsis and Forecast:
Upper low center slowly moves east to northeast across northern Lake
Superior on Wednesday with an associated 60-70kt mid level jet
streak approaching northern MI. Thus, breezy conditions and light
snow showers expected on Wednesday, favoring areas along and west of
I-75. Upper low continues to move off to the northeast Thursday with
just a few lingering snow showers possible across eastern UP.
Primary Forecast Concerns:
Cooler temperatures are expected Wednesday and Thursday with upper
level energy spinning in the vicinity and just to the north of the
area. Thus, the potential will exist for light snow/lake effect snow
showers. Low level (850mb) temps ~-10C and lacking low level
moisture suggest just some lighter snow fluttering about out there,
mainly early on Wednesday. Not really all that impressive nor
impactful.
A modest pressure gradient does remain across the area on Wednesday
with boundary layer winds ~20-25kts. Thus, winds will be breezy with
gusts near 30ish mph. Quite chilly feeling with temps in the 30s as
well. A few lingering snow showers possible across eastern upper
Thursday, with chilly temps remaining. Heights begin to rise on
Friday as temperatures increase into the 40s most locations (close
to 50 degrees Gladwin and vicinity).
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Pattern Synopsis and Forecast:
Generally zonal flow this weekend with the potential for an embedded
disturbance in the flow aloft and an attendant weak sfc cyclone.
Thus, there is the chance for precipitation early this weekend.
Ensemble guidance suggests light precipitation potential, the
steadiest south of northern Michigan. ENS guidance shows modest
probs (20-50%) for 0.1" (mix of GEFS & EPS), with very little to no
chance for 0.5" or more.
Definitely worth keeping a close eye on the early next week time
frame. Looking at ENS mean MSLP and "ensemble member pressure
centers" suggests a storm will be in the vicinity of Michigan, with
the ENS mean storm track generally southern MI-northern Ohio Valley.
The pattern is quite convoluted with pieces of energy merging/low
pressure intensifying (or not). This is about a week in the future,
so for now we`ll just monitor this development and the latest trends
in the coming days.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
MVFR to IFR producing cigs will continue to spread back west
into the region this morning, producing at times a few
insignificant sprinkles or very light snow showers. Slow
improvement expected to develop this afternoon, with more rapid
scouring out of the overcast this evening. Winds will remain
gusty as they slowly veer to a more west to southwest direction
today. Winds expected to become light this evening.
&&
.MARINE...
Gusty s to se winds veer sw late today, behind a strong cold
front. Gales will tend to diminish, except on parts of Lake MI,
where gale-gusts will continue into tonight. Brisk sw winds will
then persist all the way into Wed night.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 8 AM EDT Wednesday for LHZ345>349.
Small Craft Advisory until 8 AM EDT Wednesday for LMZ323-341-
342-344>346.
Small Craft Advisory until 8 AM EDT Wednesday for LSZ321-322.
&&
$$
UPDATE...MSB
NEAR TERM...JZ
SHORT TERM...JLD
LONG TERM...JLD
AVIATION...MSB
MARINE...JZ
Area Forecast Discussion
National Weather Service Billings MT
201 PM MDT Tue Mar 26 2024
.DISCUSSION...
Tonight through Thursday night...
Areas of snow showers, likely mixed with some rain showers,
continued to move SE through the forecast area this afternoon. Max
lapse rates continued around 8 deg C/km and the convergence zone
remained near KBIL. Areas around KBIL received an inch of snow in
a heavier area of snow showers earlier today, but that has since
melted. The surface convergence is progged to remain over central
parts of the area tonight as heights slowly build in from the W.
Kept 20-30% chances of snow showers from KBIL to KSHR W this
evening, then decreased PoPs overnight. Intensity of snow showers
will decrease after sunset. HRRR didn`t show much in the way of
fog, but kept some patchy fog in the grids per the NBM.
Upper ridge will slide across the region Wednesday through Wed.
night. Conditions will be dry, except some moisture will move into
the SW mountains Wed. night for a chance of snow. Warmer air will
advect into the area behind the convergence zone/front on Wed. and
temps will be in the 40s to 50s with 30s in the far E. Good mixing
will promote gusty winds from around KBIL to KSHR W.
SW flow with shortwaves will move over the area Thursday through
Thu. night. Cold front will push E into the area in the afternoon
and cross the region Thu. night. Some frontogenesis will accompany
the front with not a lot of moisture. Steep lapse rates will
precede the front with good mixing expected over much of the area.
Winds will be gusty W of KBIL and over the far E. Low elevation
rain showers with high elevation snow showers will overspread the
area from W to E through Thu. evening with moderate to high PoPs.
Mountain snow totals will be 2 to 6 inches in the W. Precipitation
will taper off late Thu. night as a mix of rain and snow mainly E
of KBIL. Thursday still looks warm with highs in the 50s to lower
60s. Chances of KBIL hitting 60 degrees are 60%.
Regarding any fire weather concerns, the Fosberg Index showed
values around 50 in KLVM and in the thermal belts in the foothills
Wed. afternoon through Thu. evening, otherwise Hot Dry Windy did
not show any concerns. Arthur
Friday through Tuesday...
The long term forecast remains unsettled with cooler temperatures
and increased precipitation chances through the weekend. By early
next week, drier conditions will return before unsettled weather
looks to develop once again mid to late week.
This unsettled weather pattern comes from a low pressure system
that is expected to dig south over the west coast during the
weekend, lowering heights across our region. With that, shortwave
energy will also be pulled down from the northwest, increasing
chances for precipitation and bringing below normal temperatures
to our area. While cluster analysis shows there is good agreement
on the pattern and low pressure system, we will remain in the
inherently uncertain portion of the pattern. Therefore, it is
important to continue to monitor the forecast through the week for
updates. At this time, the precipitation and colder temperatures
do not look overly significant. The NBM probabilities for 0.25
inches or more of liquid through the weekend are 70-90% over the
mountains and foothills, 40-65% over the lower elevations of south
central MT and Sheridan Co, Wy, and 15-30% over far eastern MT.
Precipitation type will be all snow in the mountains, but more of
a rain/snow mix over the lower elevations. By Sunday,
precipitation type is anticipated to switch over to snow with the
coldest air of the system moving in. Sunday also has the best
chance for precipitation across the region at this time (50-95%
chance, highest in the mountains and lowest in eastern MT). By
Monday, conditions will begin to dry out as upper level ridging
moves in. Lots of uncertainty remains on how quickly the ridging
builds in, but conditions will improve for the beginning of next
week. Ensembles suggest more unsettled weather to return by mid to
late next week.
Temperatures Friday will be near normal with highs in the 40s and
50s. Saturday and Sunday will see temperatures drop below normal
with highs in the 30s and 40s. Monday and Tuesday will see a
warming trend, although a lot of uncertainty remains in the
temperature forecast for Monday. Arends
&&
.AVIATION...
Bands of snow showers will continue to create MVFR/IFR conditions
through the afternoon and evening, mainly for areas west of KMLS,
including KLVM, KBIL, and KSHR, as well as create mountain
obscurations. By tonight, the snow showers will come to an end,
but patchy fog is possible (overall low chance) mainly east of the
foothills and west of KMLS. Arends
&&
.PRELIMINARY POINT TEMP/POPS...
Wed Thu Fri Sat Sun Mon Tue
-----------------------------------------------------------
BIL 023/052 032/058 032/052 028/045 028/039 025/048 030/060
20/U 04/W 52/R 35/O 57/S 52/S 11/U
LVM 025/049 035/051 029/049 028/047 029/041 023/048 029/059
30/N 18/W 52/O 34/O 56/S 41/B 11/U
HDN 018/053 028/062 030/052 026/047 026/041 024/048 027/060
11/U 02/W 62/R 25/O 58/S 63/O 11/U
MLS 011/042 024/054 030/044 024/040 025/038 024/043 026/054
11/B 10/B 40/B 02/O 35/S 52/S 11/U
4BQ 012/047 026/059 032/047 025/045 029/040 025/043 026/055
11/B 00/B 21/B 13/O 46/S 62/S 11/U
BHK 001/038 018/050 027/044 021/039 022/038 021/040 023/051
01/B 00/B 41/B 02/S 45/S 52/S 11/U
SHR 020/049 026/061 029/049 025/048 026/041 022/043 024/057
21/B 01/B 42/R 35/O 57/O 73/S 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service Cheyenne WY
553 PM MDT Tue Mar 26 2024
.KEY MESSAGES...
- Light to moderate snow showers will persist across south
central and southeast Wyoming through this evening. Minor
accumulations could occur beneath any heavier bands.
- Strong wind gusts up to 60 MPH will be possible near Arlington
and Elk Mountain from Wednesday evening through early Thursday
morning. A High Wind Watch is in effect.
- We continue to monitor a strong weather disturbance which may
impact southeast Wyoming and the western Nebraska Panhandle
from Friday through Sunday. Specific details remain uncertain
at this time.
&&
.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 300 PM MDT Tue Mar 26 2024
A seasonably cool afternoon across southeast Wyo and the western
Neb Panhandle on the back side of deep longwave troughing across
the central CONUS. Daytime highs have climbed into the middle to
upper 30s across the majority of the area, though we have seen a
few sites reach 40 deg F as thermal profiles continue to warm w/
the departure of the upper low. Scattered to numerous light snow
showers have persisted for much of the day, roughly along/south-
west of a line from Wheatland to Kimball near a stationary front
draped from NW-SE across south central & south east Wyoming. The
past few iterations of the HRRR have suggested the potential for
a heavier band of snow across Laramie County near Cheyenne after
20z, but would prefer to see a trend toward more organized bands
by now. As such, confidence in this 2 to 4 inch band is very low
but this will be something to monitor over the next couple hours
into the late afternoon.
Temperatures will continue to trend warmer Wednesday in response
to downslope warming off the Laramie Range. Daytime highs should
warm into the upper 40s/low 50s along and east of I-25. Trending
windier as well though in response to steepening lapse rates and
a belt of 40 to 50 knot 700-800-mb flow overhead along and south
of I-80. Both 700/850 millibar CAG-CPR gradients reach or exceed
50 meters by 00z Thursday. The presence of weak WAA aloft should
support the development of a low-level inversion, likely helping
contribute to enhanced gap flow near ARL from Wednesday evening-
Thursday morning. The GFS parameter space was sufficient to push
in-house random forest probabilities at ARL to 55-60 percent for
exceeding 58+ MPH gusts. A marginal scenario indeed, but w/ some
past experience with these WAA-driven events near ARL, sometimes
it does not take much. Opted for a High Wind Watch, valid from 6
PM MDT Wednesday through 9 AM MDT Thursday.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 330 PM MDT Tue Mar 26 2024
Breezy conditions (by Wyoming standards) will continue in the
ARL area on Thursday afternoon given the aforementioned setup,
however local machine-learning guidance generally depicts a
slight decrease in wind speeds throughout the afternoon hours.
Will have to keep an eye on a potential second round of higher
winds on Thursday later afternoon and evening as the nose of
some stronger flow aloft and decent omega fields pass through
ahead of our next precipitation-maker. Speaking of this, fast
west-southwest flow will usher in a much more saturated profile
over the Sierra Madre and Snowy ranges from around 3z Friday
onward through Friday afternoon. Earlier model guidance
supported a narrow 12hr or so window of heavy snow in the Sierra
Madres, but latest guidance now favors a bit longer-duration
moderate to possibly heavy snow event in the mountains lasting
through Saturday.
From a broad, synoptic point of view...the large trough over the
western CONUS progged to move through the Rockies from Friday
through the weekend has a dramatically different look in today`s
12z guidance. What was a cutoff low pressure system and diffuse
trough now looks quite a bit more connected as the formerly
cutoff upper-level low never really splits from the mean flow.
In fact, some ensemble guidance members now support a potent
singular longwave trough slowly moving through the west through
the weekend. This solution would favor much better lift over the
southeast Wyoming mountains. A period of frontogenetic forcing
also is beginning to become apparent along and east of the I-25
corridor, generally from Sunday morning through Monday morning
in most guidance solutions. The placement of this forcing/lift
will be key, and the location of this feature still varies
wildly among guidance members - some place it in northeast
Colorado and southeast Wyoming, others farther north from
northern Wyoming into South Dakota. Overall, the forecast for
the weekend remains quite uncertain. However, confidence has
increased quite a bit with regard to precipitation chances and
amounts, especially in the higher terrain. Another late-season
winter storm event is likely, with guidance favoring at least
an inch of QPF in the Sierra Madre, Snowy, and perhaps northern
Laramie ranges as well. Temperatures have also trended downward
given the increased precipitation forecast and stronger trough
passage. The weekend looks to feature near to slightly-above
average temperatures, down nearly 10 degrees from the forecast
yesterday. If current guidance remains on track, temperatures at
least 10 degrees below average could be present from Monday
into Tuesday of next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 546 PM MDT Tue Mar 26 2024
Show showers are decreasing in coverage, but will continue to
move through the vicinity of WY terminals plus KSNY through the
evening hours. Most of this activity should be done by
midnight. While less likely than earlier this afternoon, we
still may see brief VIS/CIG drops to IFR if a snow shower moves
directly over a terminal. Be alert for possible AMDs if that
occurs.
An area of low CIGs/fog may develop along the Cheyenne ridge
tonight into early Wednesday, which could cause IFR conditions
at KSNY and possibly KCYS (lower probability). The most likely
period for this is between 09z and 14z.
Skies will turn clearer Wednesday with NW winds increasing at
all terminals in the late morning through the afternoon hours.
Expect gusts of 25 to 35 knots in Wyoming and 20 to 30 knots in
Nebraska.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Watch from Wednesday evening through Thursday
morning for WYZ110.
NE...None.
&&
$$
SHORT TERM...CLH
LONG TERM...MAC
AVIATION...MN
Area Forecast Discussion
National Weather Service Marquette MI
713 PM EDT Tue Mar 26 2024
.KEY MESSAGES...
- Scattered rain showers this afternoon change over to snow this
evening with a cold front moving through.
- Rapidly falling temperatures behind the cold front tonight may lead
to a flash freeze on untreated roadways.
- Westerly lake effect snow develops early Wednesday morning and
continues through Thursday evening, mainly across the Copper
Country.
- Several inches of snow and blowing snow expected, mainly
across the Copper Country. Heaviest snow expected Wednesday
afternoon and night. A Winter Weather Advisory has been issued
for the Copper Country.
- Next chance of widespread precipitation occurs Friday night
and Saturday, followed by a system worth monitoring for
Monday/Tuesday next week.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 331 PM EDT Tue Mar 26 2024
Water vapor imagery and RAP analysis show a tight closed low moving
over western Lake Superior, amid broader midlevel troughing
extending across the Plains and into the Great Lakes. A pronounced
dry slot is evident across the UP and the eastern 2/3rds of Lake
Superior. At the surface, a 990mb surface low is analyzed over
western Upper Michigan, with a sharp cold front directed from
western Lake Superior to far western WI. Most of the area has been
able to enjoy a brief period of dry weather this afternoon, with Day
Cloud Phase showing lower cloud cover even mixing out across much of
the eastern half of the UP. Another embedded shortwave zipping
around the closed low is touching off another round of scattered
rain showers across north-central WI, which are moving into the
central UP already. Temperatures so far have stayed plenty warm
enough for precipitation to remain as all snow, with most of the
area hovering in the upper 40s.
This evening, the closed low will continue to move NNE over Lake
Superior, reaching Ontario closer to midnight. The frontal boundary
will soon begin tracking into the western UP, and should be through
most of the area by midnight. This should kick up another round of
light precipitation, with a quick transition over to snow. Given a
warm nose aloft in model soundings across the western UP, will not
rule out some pockets of freezing rain or ice pellets. A quick
transition over to a lake effect snow regime is expected the second
half of the night as 850mb temperatures quickly fall back to near -
12 to -15C. With winds generally out of the WSW, LES should be
confined to the far western UP, particularly the Keweenaw. Light
snow totals well below an inch are possible across much of the UP
with the passing cold front, with higher totals around an inch in
the WSW snow belts of the western UP.
Otherwise, with a rather tight pressure rise/fall couplet, and
robust CAA resulting in increasing lower level lapse rates (thus
allowing us to tap into stronger winds aloft), expect blustery
conditions to develop along and behind the cold front. Will note
that winds are already gusting up to 20-30mph in eastern MN, where
surface temperatures are already in the upper teens and lower 20s.
Temperatures likewise plummet with the passing front through the
first half of the night here in the UP. This is posing a concern for
a flash freeze tonight given wet roadways following the past day`s
precipitation. However, with most of the area having enjoyed a brief
dry period today, only a brief burst of light rain/snow this evening
with the passing front, and blustery conditions tonight potentially
helping to dry things out, this may not end up being particularly
widespread.
&&
.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
Issued at 414 PM EDT Tue Mar 26 2024
Broad troughing mid-week will gradually shift to something more
zonal as the ongoing system lifts northeast and a deep closed low
drops south to near southern California. Together, this will support
a lake effect episode until ridging to shifts eastward across CONUS,
setting up a dry Friday before another eastward progressing system
moves into the midwest for the weekend.
Beginning Wednesday, cyclonic flow overhead in the wake of a
northeastward lifting surface low toward Hudson Bay and a closed low
pushing through Minnesota, combined with 850mb temps of -17 to
-15C will support lake effect snow for the western counties of Upper
Michigan. Inversion heights of around 4-5k ft should limit the
convective potential, but access to the DGZ should still support
widespread snow showers through the day. Model soundings show strong
winds within the mixed layer, upwards of 40 mph or so in the
Keweenaw Peninsula. These blustery winds will primarily be westerly
in the morning, but shift to southwesterly by afternoon, allowing
the best convergent signal to gradually lift and focus into northern
Houghton and Keweenaw County by Wednesday night. This northward
shift coincides with increasing cyclonic flow, which would further
increase snowfall rates. This matches well with the recent HREF >1
inch per hour rates, which lights up the Keweenaw with the greatest
potential beginning late Wednesday. Overnight Wednesday, winds
become more westerly, potentially enabling the more intense showers
to dip back into northern Houghton and Ontonagon counties. Between
Wednesday afternoon and Wednesday night, confidence is high (>75%)
that snow amounts will climb above 4 inches across the west wind
snow belts and medium (50%) that 8 inches will be exceeded. This,
with the wind potential and the likely blowing snow risk, opted to
issue a Winter Weather Advisory. Lake effect snow should gradually
taper off during the day Thursday.
Elsewhere in the southern and eastern portions of Upper Michigan
Wednesday into Thursday, mostly dry conditions with winds
potentially gusting upwards of 25 mph are expected. Daytime highs
Wednesday should top out in upper 20s to near 30F in the west and
low to mid 30s south and east. Overnight lows in the teens are
expected in the interior west. Elsewhere, near 20F lows are expected.
By Friday, surface high and mid-level ridging should support a dry
and seasonable day across the region. Daytime highs near 40F or in
the 40s are expected. As the pattern shifts to something more zonal,
a shortwave will press east across the Northern Tier as a weak
southern stream impulse shifts into the Illinois/southern Wisconsin
region. As the surface low pushes eastward into Lower Michigan and
eastern Great Lakes Saturday, inverted trough tied to the northern
stream shortwave will move through the Upper Great Lakes, giving us
a chance for another rain/snow mix Friday night and Saturday.
A quick look at next week is interesting. The trough setting up over
the western US will shift eastward, enabling a low to eject out of
the Central Plains while to the north, a northern stream shortwave
will drop southeast through the Northern Plains. Whether or not
these phase is the question, as their proximity to us could support
a moderate to heavy precip event if they do. 0 and 12z
deterministic present mixed options; these phase the two features
but vary greatly in where this occurs. No surprise, ensemble
clustering highlights this spread well in the location of the
surface low lifting out of the Plains. At this point, its advised
that anyone with travel plans Monday/Tuesday keep tabs on the
forecast.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 713 PM EDT Tue Mar 26 2024
IFR/LIFR conditions will continue as a cold front continues to pass
through the area at CMX and IWD overnight and stay at CMX through
the period. It is already through CMX and IWD and will pass through
SAW within the next hour or two. Once the front passes, the rain
changes over to snow. MVFR conditions will occur at IWD by mid Wed
morning. SAW will have IFR conditions until the front moves through
early this evening, then conditions go to MVFR with a rain and snow
mix and then all snow. VFR conditions move into SAW then by Wed
afternoon. Winds will be gusty at IWD and CMX through the period.
&&
.MARINE...
Issued at 459 AM EDT Tue Mar 26 2024
Lake Superior will remain under the influence of low pres that will
track from ne IA early today across western Lake Superior this
aftn/early evening. Result will be changing wind directions and wind
speeds across the lake. Ongoing ne gales of 35-40kt across western
Lake Superior will temporarily subside in the vcnty of the passing
low this aftn. Over eastern Lake Superior, se winds will
occasionally gust to 35kt gales this morning closer to the
International Border. As the low lifts n of the area this evening, w
to wsw winds will ramp up to 35-40kt gales over much of w and
central Lake Superior. These gale force winds will continue thru Wed
before diminishing by late Wed evening. Internal probabilistic
guidance indicates a 25-35pct chc of gusts into the 40-45kt range in
a large area surrounding the Keweenaw Peninsula. Freezing spray will
also occur during these gales, and some hvy freezing spray will
occur at times over portions of western Lake Superior late
tonight/Wed morning. Westerly winds of 25-30kt will then prevail
across Lake Superior late Wed night thru Thu. A high pres ridge will
then arrive on Fri, leading to winds diminishing to mostly under
20kt. Wind should remain mostly under 20kt into and thru the
upcoming weekend.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Winter Weather Advisory from 2 PM Wednesday to 8 AM EDT
Thursday for MIZ001>003.
Lake Superior...
Small Craft Advisory until 8 AM EDT /7 AM CDT/ Wednesday for
LSZ240-249>251.
Gale Warning until 11 PM EDT /10 PM CDT/ Wednesday for LSZ162-
244-263-264.
Heavy Freezing Spray Warning from 5 AM EDT /4 AM CDT/ to 2 PM
EDT /1 PM CDT/ Wednesday for LSZ162-240>244-263-264.
Small Craft Advisory until 8 PM EDT /7 PM CDT/ this evening
for LSZ241>243.
Gale Warning until 11 PM EDT /10 PM CDT/ Wednesday for
LSZ241>243.
Small Craft Advisory until midnight EDT tonight for LSZ245>248.
Gale Warning from midnight tonight to 5 PM EDT Wednesday for
LSZ245>248-265.
Gale Warning from midnight tonight to 11 PM EDT Wednesday for
LSZ266.
Lake Michigan...
Small Craft Advisory until 8 AM EDT Wednesday for LMZ221-248-
250.
&&
$$
SHORT TERM...LC
LONG TERM...JTP
AVIATION...07
MARINE...Rolfson
Area Forecast Discussion
National Weather Service Reno NV
319 PM PDT Tue Mar 26 2024
.SYNOPSIS...
The region expects to see the warming trend continue this
afternoon along with mostly dry weather following the showers this
morning. The first of two impactful weather systems arrives in
the area during Wednesday afternoon with the passage of a cold
front. Gusty to strong winds across the region as well as rain in
the valleys and snow in mountains are all expected with this
initial system going through Thursday morning. Following a brief
break in the remainder of Thursday, a second impactful system is
in the forecast that will cause more chances for mountain snow and
valley rain starting on Friday and going through Easter weekend.
Those with outdoor holiday plans are encouraged to watch for the
latest forecast information.
&&
.DISCUSSION...
According to the latest RAP analysis, the CWA currently has a strong
northwesterly flow aloft being underneath the forward portion of an
upper air ridge this afternoon. Forecast guidance shows the ridge
continuing to move eastward with its axis passing over the CWA on
Wednesday morning. For the rest of today and into tomorrow morning,
dry conditions are expected with this upper air setup with slightly
warmer daytime highs today and tomorrow compared to Monday`s
highs.
On Wednesday afternoon, models continue to show an upper air low
moving towards the coast of the Pacific Northwest turning the upper
air flow to southwesterly by the late afternoon/evening hours as the
low pushes the ridge eastward. With this upper air setup, a cold
front associated with a surface low off of the coast of WA looks to
make its way across the CWA bringing some stronger winds and wintry
precipitation with it to the region through the night into Thursday.
Latest NBM probabilities show around 80-90% probability of greater
than 6 inches of snowfall within 24 hours for the Sierra ridgetops
in the far western portions of the CWA along with a 10-30% chance
for greater than 12 inches of snowfall in the same location. Higher
elevation portions of western Mono County and the Tahoe Basin not
included in the previously mentioned area look to have around a
50- 60% probability for 4 inches of snowfall or greater in 24
hours. The precipitation type for lower elevation portions of the
CWA still looks to be mostly rain though some light snow may mix
in overnight. Little to no snowfall accumulation is expected for
lower elevation areas within the CWA at this time. As for wind
gust probabilities, Sierra ridge gusts have a 60-80% probability
of around 65 mph or greater. Currently, the forecast calls for
Sierra Ridges gusts ranging around 70-80 mph late Wednesday with
some locations seeing a little over 90 mph possible. With these
expected winds and snow chances, hazardous traveling conditions in
the Sierra Ridge are expected due to the expected snow amounts as
well potential blowing snow late Wednesday and going into early
Thursday. Please see the Winter Weather Advisory in effect on
Wednesday and Thursday for Mono County and the Tahoe Basin for
more details. There is also a Lake Wind Advisory in effect
Wednesday evening through Thursday morning for the Pyramid Lake
area with expected gusts up to 35 mph. By Thursday afternoon,
precipitation chances look to taper off for most of the region
though remaining around 10-20% within the Sierra Mountain portions
through the rest of the day.
For Friday, long term model guidance show the upper air low
traveling southward just off the Pacific Coast until it is west of
central CA when it cuts off more from the general upper air flow.
There looks to be some discrepancy between the ECMWF and GFS models
going forward from Saturday through early Monday as the ECMWF
moves the low east and over the CWA on Saturday morning before
opening into a trough over the Rockies late Sunday into early
Monday. The GFS as an alternative takes the low on a path that
moves around the south of the CWA on Saturday and Sunday before
reaching the Four Corners area on Monday. Due to this difference
in tracks, the details on the impactful weather system within the
area still remain rather uncertain though models do agree that
precipitation chances will return once again for Friday, Saturday,
and Sunday with a surface low system moving south along the
Pacific Coast before cutting across Southern CA on Saturday and
Sunday. While there is good confidence of wraparound valley rain
and mountain snow across the region during these days, the model
forecast snow and QPF totals have been fluctuating quite a bit
lack of consensus in the low`s track. Please continue to watch for
forecast updates for the holiday weekend especially those with
outdoor plans and events.
Precipitation chances look to taper off within the CWA on Monday
with long term model guidance showing an upper air ridge starting to
move over the Pacific Coast and giving the CWA a northeasterly upper
air flow. This positively tilted upper air ridge is then forecast
to move over the CWA on Tuesday allowing for the dry conditions
to persist as well as allow for warmer daytime temperatures.
-MRC
&&
.AVIATION...
VFR conditions are expected for all REV terminals going through the
remainder of today and into tomorrow morning. Generally westerly
winds gusting up to around 20 kts during the afternoon that decrease
going into the night are in the forecast for most terminals with the
exception being with KTVL seeing slower southerly winds through the
rest of today and into tomorrow. With a cold frontal passage
expected Wednesday afternoon and evening, surface winds look to
speed up a bit and turn more southwesterly as chances for
precipitation expect to enter the region which may affect flight
restrictions later Wednesday and into Thursday.
-MRC
&&
.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory from 2 PM Wednesday to 11 AM PDT
Thursday NVZ002.
Lake Wind Advisory from 5 PM Wednesday to 2 AM PDT Thursday
NVZ004.
CA...Winter Weather Advisory from 2 PM Wednesday to 11 AM PDT
Thursday CAZ072.
Winter Weather Advisory from 5 PM Wednesday to 11 AM PDT
Thursday CAZ073.
&&
$$