Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/02/23
Area Forecast Discussion
National Weather Service Cheyenne WY
540 PM MDT Mon May 1 2023
.SHORT TERM...(This evening through Wednesday night)
Issued at 300 PM MDT Mon May 1 2023
Forecast concerns deal with increasing chances for showers and
storms each day through the week.
Currently...High pressure currently located over central South
Dakota with a stalled out cold front over western Carbon County.
Upper ridge of high pressure currently over Rivertons CWA south
into Grand Junctions CWA. This ridge will shift east over the next
24-36 hours...allowing more moisture to surge north out of western
Colorado.
Latest HRRR guidance does show isolated convection developing late
this afternoon for a couple hours across southern Carbon County.
Everywhere else remains dry. Do have low 20 percent chance PoPs
over the Snowy and Sierra Madre Ranges through 01-02Z this
evening.
Better chances for convection out west Tuesday afternoon as upper
ridge axis shifts east into the Panhandle. ECMWF/GFS/SREF and to a
lesser extent the NAM all show fairly widespread QPF across
Carbon and Albany Counties Tuesday afternoon. East of the Laramie
Range...conditions expected to remain dry.
Scattered showers and storms possible Wednesday afternoon across
the southern half of the CWA. Better chances will occur
Thursday...but areas along the I-80 corridor from Sidney to Elk
Mountain stand the best chance for afternoon showers/storms.
.LONG TERM...(Thursday through Monday)
Issued at 300 PM MDT Mon May 1 2023
An unsettled pattern will plague the extended forecast with moist
southwesterly flow and an upper-level trough, leading to near-daily
chances for precipitation. Luckily, temperatures will continue to be
on the mild side, with above average temperatures expected.
The upper-level ridge that was over the CWA for the beginning of the
week begins to break down and shift further east on Thursday. This
will open the door for moist southwesterly flow to stream into the
region. Moist flow combined with energy and lift from an incoming
upper-level trough will spark pretty widespread precipitation across
the area. Model sounding from the GFS show MUCAPE values of 500 to
1500 J/kg across the CWA which will likely lead to thunderstorms.
However, the potential for severe thunderstorms looks limited by
weak shear. These storms do, however, have the potential to produce
heavy rain with good rainfall totals. Model soundings show PW values
of ~0.50 inches in southeast Wyoming and ~0.75 in western Nebraska.
The wet weather continues into Friday thanks to the moist 700 mb
flow and trough moving into the CWA. Again, afternoon thunderstorms
look to lack any severe elements due to weak instability and shear.
Heading into the weekend, a similar set-up will likely lead to
afternoon scattered thunderstorms, at least on Saturday.
As mentioned, temperatures during this time period will remain above
average. The warmest day will be Thursday as temperatures will still
be influenced by the ridge. Expect highs in the 70s and 80s.
However, increasing cloud cover on Thursday ahead of a "cool" front
may lead to slightly cooler highs than expected. The "cool" front
moves through early Friday morning, dropping high temperatures by
about 10 degrees. Highs on Friday will range from the upper 50s to
low 70s. These will continue into the weekend as 700 mb
temperatures stay steady in the -2C to +2C range.
&&
.AVIATION...(For the 00Z TAFS through Tuesday afternoon)
Issued at 540 PM MDT Mon May 1 2023
A strong upper level ridge axis will remain over the state of
Wyoming tonight with generally clearing skies and light winds. This
ridge axis is expected to drift eastward Tuesday allowing a weak
disturbance aloft to move towards the Wyoming/Colorado border. A few
showers or thunderstorms are possible late Tuesday afternoon through
Tuesday evening, mainly across southeast Wyoming.
HAZARDS/WEATHER TRENDS: VFR Conditions will continue through
Tuesday. A few short-lived thunderstorms are possible at KRWL, KLAR,
and KCYS after 20z Tuesday, but confidence is too low to include in
area TAFs at this time.
&&
.FIRE WEATHER...
Issued at 300 PM MDT Mon May 1 2023
Two a day Fire Weather Forecasts begin today. Expect a morning
and afternoon Fire Weather Forecast each day through October.
Tranquil weather conditions this afternoon as high pressure over
South Dakota continues easterly wind flow over much of southeast
Wyoming and Nebraska Panhandle this afternoon. A stalled out cold
front lays across Carbon County...that will slowly move east this
evening into Tuesday. Southwest wind flow west of the front
Tuesday expected to begin pulling moisture north from Colorado
during the afternoon. This will create afternoon showers and
thunderstorms west of the Laramie Range. Moisture increases each
day with greater coverage and intensity of showers and storms each
afternoon. Most widespread coverage of showers and storms looks
to be Thursday. Much of our fire weather zones along and west of
the Laramie Range expected to see storms that could produce heavy
rainfall. This wet weather finally spreads east of the Laramie
Range Friday and Saturday.
&&
.HYDROLOGY...
Issued at 300 PM MDT Mon May 1 2023
Flood Watch has been issued for the Little Snake River from 6 AM
Wednesday through 6 AM Saturday. River is running near or at
bankfull currently.
Previous Discussion from 310 AM MDT Mon May 1 2023
Warm temperatures through Thursday will accelerate the snowmelt runoff
into the Little Snake River and Upper North Platte River basins. The
Little Snake River near Dixon is forecast to climb above action stage
early this week. Slow rises were evident on the Little Snake River at
Baggs and near Savery, and Upper North Platte River at Saratoga and
near Sinclair. Snow levels will continue to be monitored later this
week for rain on snow with the approach of a upper level low pressure
system from the southwest.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...GCC
LONG TERM...SF
AVIATION...TJT
FIRE WEATHER...GCC
HYDROLOGY...MJ/GCC
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
525 PM MDT Mon May 1 2023
...New AVIATION...
.SYNOPSIS...
Issued at 200 PM MDT Mon May 1 2023
Moisture will slosh into the region tonight through Wednesday
night, increasing chances for showers and a few thunderstorms
mainly along and east of the Rio Grande. Drier and gusty showers
and isolated storms are possible over southwest New Mexico.
Temperatures will remain warm. Southwest winds strengthen and
humidities crater Thursday and Friday, leading to potential for
more widespread critical fire weather conditions. The upcoming
weekend appears dry, breezy to windy and warm.
&&
.DISCUSSION...
Issued at 200 PM MDT Mon May 1 2023
Models suggest today`s considerable high clouds will hang around
tonight and then at least partially clear out Tuesday. The RAP and
HRRR continue to hint at some isolated convection moving
northward out of Old Mexico into south central NM later tonight
with spotty light rain and most likely gusty winds given the sub
20 degree dewpoints over the region this afternoon. The better low
level moisture will slosh westward Tuesday into Wednesday
potentially reaching the Rio Grande Valley although it may be
rather shallow, with the deeper low level moisture along the
mountains to the east. The GFS indicates a moisture surge may move
into southwest/south central NM as the upper low along the CA
coast starts to eject into AZ and NV on Wednesday night but again
would suspect low level moisture may be somewhat lacking. Pretty
much stuck with the NBM pops for this forecast package which
seemed to have the general trends although may be a little high. A
serious drying trend commences over southwest NM by Thursday, and
low level moisture east of the Rio Grande Valley is swept out
Thursday night and Friday. Consequently, breezy to windy and dry
conditions develop with higher potential for critical fire weather
conditions. This dry southwest flow pattern persists through the
upcoming weekend. Temperatures will be seasonably warm, and
overnight lows should cool down given the dry air mass.
&&
.AVIATION...
(00Z TAFS)
Issued at 530 PM MDT Mon May 1 2023
Plenty of cloud coverage tonight with Gulf moisture moving
northward into S NM/W TX. Weak convective activity ongoing south
of the border in Chihuahua will drift north overnight, leading to
isolated rain showers. Much of this will result in virga showers
due to very air surface air, leading to low precipitation, gusty
downdrafts, and surface winds up to 25 knots. Will need to monitor
TAFs for any gust fronts next few hours. CIGs likely remaining
around 10-12K FT overnight, clearing by early Tuesday morning.
&&
.FIRE WEATHER...
Issued at 200 PM MDT Mon May 1 2023
An upper low is forecast to drop southward along the CA coast
bringing occasional bouts of stronger south to southwest winds and
brief moisture surges into southwest NM through Wednesday
evening. This will lead to potential for some dry and gusty
showers or isolated storms and elevated fire weather conditions.
One such surge in indicated by short term models for tonight
although it may be more focused up the Mesilla Valley/Rio Grande
Valley. Another may occur Wednesday night but models seem to have
more disagreement. East of the Rio Grande low level moisture will
slosh in and out, with better chances for wetting showers and
thunderstorms late Tuesday through Wednesday night, although can`t
rule out a few drier storms late Tuesday. Convection chances over
the forecast area diminish rapidly Thursday from west to east as
drier and stronger southwest winds dominate. Widespread critical
fire weather conditions are possible Thursday and Friday as a
result. Dry, breezy to windy and warm weather is indicated for the
upcoming weekend.
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 62 86 59 87 / 20 10 10 10
Sierra Blanca 56 81 53 81 / 20 20 20 20
Las Cruces 57 86 54 86 / 20 10 0 10
Alamogordo 56 84 53 84 / 10 20 10 20
Cloudcroft 42 60 41 60 / 10 30 20 40
Truth or Consequences 54 83 51 83 / 10 10 0 10
Silver City 48 75 48 74 / 10 10 0 0
Deming 51 83 49 83 / 20 10 0 10
Lordsburg 50 80 49 81 / 10 10 0 0
West El Paso Metro 59 83 58 84 / 20 10 10 10
Dell City 55 86 51 85 / 10 20 20 20
Fort Hancock 55 87 53 88 / 20 10 10 10
Loma Linda 55 79 52 78 / 20 10 10 10
Fabens 57 87 54 87 / 20 10 10 10
Santa Teresa 55 82 54 83 / 20 10 0 10
White Sands HQ 62 84 58 83 / 20 10 10 10
Jornada Range 54 82 51 82 / 20 10 10 10
Hatch 56 84 52 83 / 20 10 0 10
Columbus 55 84 54 83 / 20 10 0 0
Orogrande 57 83 54 83 / 20 10 10 20
Mayhill 47 72 43 71 / 10 30 20 40
Mescalero 46 71 43 72 / 10 40 20 40
Timberon 44 70 43 70 / 10 30 20 30
Winston 47 74 44 73 / 10 10 0 0
Hillsboro 52 80 49 79 / 10 10 0 0
Spaceport 54 81 50 81 / 10 10 0 10
Lake Roberts 44 75 43 75 / 10 10 0 0
Hurley 46 79 45 79 / 10 10 0 0
Cliff 41 82 39 82 / 10 10 0 0
Mule Creek 46 76 46 75 / 10 0 0 0
Faywood 49 78 48 78 / 20 10 0 0
Animas 51 81 49 81 / 10 0 0 0
Hachita 51 82 50 81 / 10 0 0 0
Antelope Wells 49 81 48 80 / 10 0 0 0
Cloverdale 49 75 48 73 / 10 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...None.
NM...None.
&&
$$
SHORT TERM...99
LONG TERM....99
AVIATION...30-Dennhardt
Area Forecast Discussion
National Weather Service Glasgow MT
858 PM MDT Mon May 1 2023
.DISCUSSION...
EVENING UPDATE:
Winds continue to be 10-20kts through the western half of the CWA,
while we already had winds forecast to subside in magnitude. So
blended in ConsShort and HRRR which had a better grasp of current
winds. Otherwise, the below forecast remains valid.
-Enriquez
PREVIOUS DISCUSSION:
Omega block ridge has established itself over the area today and
will last through most of the week. During this time things will
remain dry and temperatures will rise to above early May averages.
Eventually as the week progresses the west coast trough will
slowly track to the northeast bringing rain chances a little bit
closer each day. By Thursday and Friday this feature will get
close enough to kick up the winds high enough that the first Lake
Wind Advisories of the season will likely have to be issued.
Precipitation chances could enter the southwestern zones as soon
as Thursday night and overspread most of the area on Friday. The
trough will continue sitting over our area next weekend keeping
things unsettled.
-Bernhart
&&
.AVIATION...
LAST UPDATED: 0300Z
FLIGHT CAT RANGE: VFR
DISCUSSION: High pressure is expected to bring dry weather and VFR
conditions over the next few days.
WIND: SE 10-15kt tonight, becoming 15-20kt SE winds Tuesday.
-Bernhart/Enriquez
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
weather.gov/glasgow
Area Forecast Discussion
National Weather Service Gray ME
1043 PM EDT Mon May 1 2023
.SYNOPSIS...
Even through the threat for heavy rain has ended, flooding in
some areas will continue through tonight with river flooding
possibly lasting for another couple of days. Unsettled
conditions will linger through the middle of this week as an
upper low remains near the area, but improvement in weather and
temperatures is foreseen this weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
1038 PM Update...Have updated the pops this evening with a few
showers moving across portions of the western part of our
forecast area per latest surface reports and radar imagery. Made
adjustments to the fog grids as plenty of low level moisture
will allow for the expansion of fog overnight. Minor edits made
to the temperature, dew point and wind near term forecasts.
Update...Scattered showers continue across western portions of
the forecast area per latest radar imagery. Most of the
precipitation remains away from the stable layer near the coast,
however Portsmouth did report a brief shower. Have upped pops
in most areas with the latest trends and HRRR solution for the
next few hours.
Will continue with patchy late night fog as there is plenty of
moisture near ground level to produce lowered visibilities. Min
temperatures will drop down into the upper 30s to mid 40s by
morning.
Prev Disc...
Sfc low ans front lift N-NE tonight through Quebec and the
maritimes, and this should allow for a very brief period of
ridging. However, a weak wave rotating around 500 MB closed to
our left, could pus some light SHRA into NH and the ME mtns this
afternoon into early evening. Elsewhere it should stay mostly
clear. Through midnight. After midnight, will see the upper
level get closer as another weak wave rotates around it, which
will spread clouds in NH in the predawn, and over into wrn ME
toward daybreak. Some showers could work back into Srn NH around
sunrise, but most of the precip will likely not move in until
Tue morning. Lows should drop off quickly this evening, and then
slow their fall after midnight as wind shifts and more clouds
move in, along with some patch fog along the coast and on the
coastal plain. Lows will bottom out in the upper 30s in the
mtns, and the low to mid 40s in the S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
On Tuesday, and Tuesday night, the 500 MB low shifts slowly SE
from southern Ontario into central PA, it goes through several
pulses, as energy move in and out of it, but this means several
rounds of showers every every 8 hours or so, so expect cool and
showery conditions Tuesday and Tuesday night. Ern zones could
luck out Tuesday as they low is further W, but the showers will
eventually move in there by Tue afternoon. Highs on Tuesday will
Generally range from 50 in the N to around 55 in the S, with
lows Tue night in the low to mid 40s.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
The very slow continued approach of the upper low will result in yet
another mostly cloudy and showery day as more PVA aloft provides the
necessary lift. Ensemble means from the ECWMF and GFS are
advertising around 0.25" to 0.50" of additional rainfall, perhaps
higher as we approach the foothills and mountains with
aided orographic lift. With saturated ground from the copious
amounts of rain we saw last night/this morning along with
forecast rain Tues/Tues night, localized minor flooding can`t be
ruled out over the interior, particularly the mountains. Temperature
profiles may be even be cool enough for some snow to mix in across
northern areas into Wednesday night, and some light snow accums are
possible in the higher elevations.
The pesky low will finally pass off to our south and east by
Thursday morning, and while mostly cloudy conditions will continue,
shower coverage is not expected to be as high as previous days with
lesser upper support. Temperatures will remain cool just either side
of 50 degrees.
Since the upper low will be farther off to our east by Friday we
should start seeing a drying trend, especially toward the later part
of the weekend into next Monday with a ridge attempting to build in
(also bringing some warmer temperatures). However, the GFS in
advertising a couple of shortwaves diving south through the area on
the backside of the upper low Friday and Saturday, which could still
produce a few rain showers.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Short Term...The brief period of VFR conds comes to an end this
evening on the coast, and by late tonight elsewhere, as the
flow once again turns back onshore , but is weaker. Variable
conds expected , from MVFR to IFR expected in rounds of showers
Tuesday and Tuesday night.
Long Term...In addition to MVFR to IFR ceilings possible Wednesday
into Thursday, high coverage of rain showers and patchy fog will
also cause reductions in visibility, potentially to IFR, during this
time as well. It should be noted that some sites could see
occasional improvements to VFR outside of rain showers.
Can`t rule out a few showers on Friday and Saturday, but for the
most part, VFR conditions are expected into the upcoming weekend.
&&
.MARINE...
Short Term...SCA level winds will continue to diminish late
today and this evening, but seas will stay high right through
Tuesday, and although the bays should see SCA conds end
overnight, the open waters will be stuck with high seas at least
through the day on Tuesday.
Long Term...SCA conditions continue through Wednesday due to seas
remaining greater than 5 ft, although east to northeast winds could
occasionally gust to 25 kt. Going into Wednesday night through
Friday, north to northeast winds are expected to increase with gusts
over 25 kt looking more probable, prolonging the SCA conditions
through the end of the work week over portions of the waters. Winds
and seas are expected to diminish this weekend, bringing improving
conditions across the waters.
&&
.HYDROLOGY...
Several flood warnings remain in effect, some until Tuesday,
while some streams and creeks should be trending down, and
continue to fall overnight. So, if you`re out, watch for
flooded roads and pay heed to closed road signs and barriers.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 2 PM EDT Wednesday for ANZ150-152-
154.
Small Craft Advisory until 4 AM EDT Tuesday for ANZ151-153.
&&
$$
NEAR/SHORT TERM...Cannon
LONG TERM...Combs
Area Forecast Discussion
National Weather Service Indianapolis IN
930 PM EDT Mon May 1 2023
.Forecast Update...
Issued at 930 PM EDT Mon May 1 2023
Few significant updates to the going forecast this evening. Made
minor low temperature adjustments based on latest HRRR/LAMP
guidance, primarily along the Lafayette/Indy/Rushville corridor.
Minor adjustments made to PoPs to bring them in line with latest
regional radar trends and continued expectation that showers will
steadily pull eastward and likely end for most of the area late
tonight.
Otherwise, lowered wind gusts overnight as latest ACARS data show
low level inversion development has been much stronger than larger
scale models originally anticipated, which will significantly limit
gustiness overnight.
&&
.Short Term...(This evening through Tuesday)
Issued at 258 PM EDT Mon May 1 2023
* Wind gusts to 40 mph through this evening
* Widespread rain north of I-74 diminishing overnight
* Isolated showers tomorrow, but still colder than normal
.This evening and tonight...
One of the coldest beginning`s of May for much of Central and North
Central Indiana with highs struggling to get out of the 40s! An
expansive upper level low over the Great Lakes is responsible for
the low clouds, rain, and wind across the region. Latest satellite
and radar imagery vividly show an upper trough rotating about the
main upper low into Central Indiana this afternoon with steady
stratiform rain along and north of I-74. This upper feature will
keep rain and lower clouds around through this evening, then
precipitation begins to diminish in coverage and intensity
overnight.
In addition to very cold highs for this time of year, a strong 40 kt
low level jet and a strong pressure gradient are resulting in gusty
winds to 40 mph across the region as well. Strongest winds have
occurred south of the I-74 corridor where the cloud deck is thinner
and boundary layer heating has led to deeper mixing. Expect winds to
remain elevated overnight around 10 to 20 mph; however the stronger
gusts of 30 to 40 mph will likely diminish after sunset.
Overnight temperatures won`t fall too much from daytime highs as
persistent cloud cover and winds prevent significant boundary layer
cooling. Expect lows in the upper 30s to low 40s.
.Tuesday...
Similar weather pattern continues into tomorrow, albeit a few
degrees warmer and less shower coverage. The main upper low pushes
northeast towards Toronto, but multiple upper waves will continue to
rotate around it into the region. RAP cross sectional views of the
atmosphere show mid level dry air advection tomorrow afternoon,
which may lead to a few breaks in the clouds at times, especially
across the south and western portions of Indiana. Keeping at least
20 PoPs across the northern 2/3 of the region as isolated showers
will likely persist under the cyclonic flow pattern. Lower
confidence exists in the timing of these weaker waves; however it
does look like tomorrow will be significantly drier than today has
been. With a strong low level jet aloft and a bit more boundary
layer heating tomorrow, expect gusts of 20-35 mph during the
afternoon hours. Temperatures should rise into the lower 50s for
most locations, except the far northeastern counties where clouds
and showers will be more prominent. However, since there is lower
confidence in timing of smaller waves, any afternoon showers would
likely cool temperatures down back into the 40s for a brief period.
Best chance of that occurring is along and north of I-74.
&&
.Long Term...(Tuesday night through Monday)
Issued at 258 PM EDT Mon May 1 2023
The long term period will start off still under the influence of an
upper level low slowly drifting east from the Great Lakes
continuing the chilly conditions. At the surface, high pressure
will start to move in for midweek, allowing a break in rain as
well as sunnier skies than we`ve seen the last few days. The first
few nights of the long term will have a risk of additional frost
with lows in the 30s, but as the the pattern changes through the
period, there will be a warming trend into next week.
Towards the end of the week, a surface low in the central plains in
addition to return flow on the backside of the exiting high may
bring some chances for rain. Confidence is on the lower end for this
precipitation at the moment as at the upper levels a ridging pattern
will be moving in, which may suppress those rain chances. There is
quite a bit of noise in the models for next week, but central
Indiana could see another low pressure or troughing system that
would bring additional chances for rain. In terms of temperatures
for the latter half of the period, there is a high confidence in the
warming trend as there is general agreement on a regime allowing for
highs in the 60s and 70s and lows in the 40s and 50s.
&&
.Aviation...(00Z TAF Issuance)
Issued at 721 PM EDT Mon May 1 2023
Impacts:
* Showers early in the period gradually ending.
* Strong west northwesterly winds occasionally gusting above 20KT
this evening and again on Monday.
* MVFR ceilings return to LAF/IND 09-12Z and persist through 18-20Z
Monday.
Discussion:
Large upper low continues to spin over the eastern Great Lakes this
evening. Rain associated with this low will gradually move east of
the sites this evening. Cannot rule out additional showers at times
during the period, but chances are too low for mention at this time.
Widespread VFR ceilings will remain the rule until late tonight,
when MVFR ceilings are likely to build back into LAF/IND in the 09-
12Z time frame. These ceilings will likely persist into the early-
mid afternoon hours, 18-20Z before returning to VFR. HUF/BMG appear
likely to remain VFR throughout.
Winds will remain breezy from about 280-300 degrees. Gusts will be
much more sporadic overnight tonight and thus will not mention. More
consistent gustiness will return after daybreak Monday, with gusts
20-26KT likely at the sites through the day Monday.
No significant obstructions to visibility are expected through the
period.
&&
.IND WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Update...Nield
Short Term...CM
Long Term...KH
Aviation...Nield
Area Forecast Discussion
National Weather Service Marquette MI
627 PM EDT Mon May 1 2023
.SHORT TERM...(The rest of this afternoon through Tuesday night)
Issued at 308 PM EDT MON MAY 1 2023
In the short term, the historic spring winter storm continues across
the north central and western U.P. today into Tuesday as satellite
imagery shows the deformation zone of a low pressure digging into
Lower MI early this afternoon remaining over us. With high pressure
ridging persisting over the Rockies and Newfoundland for the first
half of this week, in addition to the low pressure over New England
phasing with the previously mentioned low, expect rain and snow to
continue across the region through the overnight hours into Tuesday.
As colder Canadian air slowly trudges eastwards the rest of today
into tonight, we are beginning to see rain transition over to
snowfall over the eastern half of the U.P. today; this is quite
evident over Alger County, as the transition to snowfall began this
morning over the west and is slowly moving eastwards with time. With
very heavy, wet snow and strong winds occurring over the north
central last night and this morning, large scale power outages and
multiple car wrecks have been seen across Marquette and Baraga
counties. With the low from New England phasing-in this afternoon
and evening, expect the heavy, wet snow and strong winds to continue
this afternoon into this evening as the sfc low over northern
Ontario retrogrades to the SW slightly. Therefore, expect to see
more reports of closed roads, power outages, downed powerlines and
trees/branches/etc., and car wrecks this afternoon through tonight
into Tuesday morning. IF YOU DON`T HAVE TO TRAVEL, PLEASE STAY OFF
THE ROADS, AS DRIVING CONDITIONS COULD BE DANGEROUS IN SPOTS,
PARTICULARLY ALONG THE HIGHER TERRAIN AREAS OF BARAGA AND MARQUETTE
COUNTIES NORTH AND WEST OF NEGAUNEE!!! In addition, with strong
winds coming off of Lake Superior today into this evening, some
lakeshore flooding and beach erosion could be seen along the tip of
the Keweenaw and from Marquette County eastwards.
CAMs guidance hints at an uptick in precip rates this afternoon into
early this evening as the best moisture and forcing from the lows
phasing over northern Ontario today and tonight moves across the
area. While snowfall accumulations may struggle over salted and
plowed roads this afternoon, roads over the Michigamme Highlands and
bridges may accumulate slushy snowfall quickly, which would greatly
reduce traction and could lead to the formation of ice in spots
where the liquid refreezes. Once we move into the early evening
hours, expect heavy, wet snowfall to begin sticking to roads more
efficiently across the area.
Once we get past midnight tonight, expect the precip rates to slowly
decrease with time as drier air slowly creeps into the region; by
the overnight hours tonight, expect the precip to have become purely
snowfall across Upper MI. While drier air should slowly cut down on
snow totals, some lake and upslope enhancement across the NNW snow
belts should keep snowfall rates from dropping all that much,
although the snowfall might be a little bit drier than what was seen
this morning through early this afternoon (think 10:1 instead of 6:1
snow-to-liquid ratios). As we move into Tuesday, snowfall slowly
diminishes throughout the day for most of the area from east to west
(some CAMs like the HRRR show a sharp cut-off between snow and no
snow pushing from east to west). However, there may be an uptick in
snowfall over the western U.P. Tuesday as heavier snowfall moves
back over the area; would not be surprised to see moderate to heavy
snowfall rates return over the far west near Ironwood Tuesday, even
though they are currently experiencing light rainfall and were only
seeing light snowfall earlier this morning. As with the north
central today and tonight, the western U.P. may see some significant
snowfall accumulations over elevated sfcs and grassy areas Tuesday;
travel could be very difficult to near impossible at times. As the
phased low moves into the Eastern Great Lakes Tuesday evening, dry
air from Canada quickly moves back over the U.P. and ends most of
the snowfall by midnight Tuesday night.
.LONG TERM...(Wednesday through Monday)
Issued at 335 PM EDT MON MAY 1 2023
Expect much better weather conditions by the middle of this week and
going through this weekend as WAA and ridging slowly builds across
the area. Expect high temps Wednesday, while below normal, to return
to the 40s across the area, with the south central possibly getting
into the low to mid 50s. With each progressive day during the latter
half of this week through this weekend expect the temps to increase;
by next Monday, we could see high temps back in the 60s and 70s
across the area.
Precip-wise, a shortwave low digging through the area Wednesday
night into Thursday may bring some rainfall across the western U.P.;
there is a slight chance that there may be some rumbles of thunder
during the afternoon hours Thursday. As a troughing pattern builds
over the Great Plains during the middle of this week into this
weekend, rain chances persist across the western U.P. late this week
into this weekend; medium range guidance currently hints at a low
lifting from the Plains through the Upper Midwest into Canada late
this weekend/early next week as ridging builds back over the Plains,
which may bring rainfall back across Upper MI. That being said,
though, model guidance is kind of everywhere with the placement of
the low and its track at the moment.
One significant final concern for the middle to end of this week is
river flooding. When the wet, heavy snowfall melts later this week,
around 1 to 4 inches of liquid could inundate creeks, riverbeds, and
other hydrologic structures across northern Upper MI. With soils
already being incredibly saturated and river flooding already being
seen in places like Chassell, at least minor river flooding could be
seen in the north central and western U.P. for the latter half of
this week as warming temps quickly melt the snowfall.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 627 PM EDT MON MAY 1 2023
There has been some improvement to MVFR at IWD and CMX and this will
last through most of the period at IWD, but CMX will fall back to
IFR late this evening and then stay there. SAW will remain at IFR
with periods of LIFR tonight in heavier snow as well. In addition,
the strong northerly winds will persist with gusts up to 25 to 35
kts. LLWS will also be a threat at SAW tonight.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 348 PM EDT MON MAY 1 2023
A low pressure being phased with is bringing NNW gales to 35 knots
to storm force winds up to 50 knots across Lake Superior this
afternoon into early this evening. As the low finishes phasing this
evening, expect the winds to slowly die down late tonight to NNW
gales up to 45 knots over the central and eastern lake. As the low
pressure continues to dig towards to Eastern Great Lakes and New
England Tuesday and ridging builds in from the west, expect winds to
continue diminishing, going below gales by midnight Tuesday night.
By Wednesday, expect winds to lighten to 20 knots or less as sfc
high pressure settles over the region. The light winds continue
until Thursday, when a troughing pattern over the Great Plains
encroaches from the west, bringing NE winds of 20 to 30 knots back
over the far western lake. However, expect light winds of generally
20 knots or less to dominate the rest of the fcst period as high
pressure ridging stubbornly refuses to leave the area.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Flood Watch through Tuesday evening for MIZ001>006-009>011-084.
Lakeshore Flood Warning until 5 AM EDT Tuesday for MIZ001.
Winter Storm Warning until 8 AM EDT Tuesday for MIZ001-003.
Winter Storm Warning until 2 AM EDT /1 AM CDT/ Tuesday for
MIZ002-009-010-084.
Winter Storm Warning until 11 AM EDT Tuesday for MIZ004>006.
Lakeshore Flood Warning until 8 AM EDT Tuesday for MIZ005-006.
Winter Weather Advisory until 2 AM EDT /1 AM CDT/ Tuesday for
MIZ011-013.
Lake Superior...
Gale Warning until noon EDT /11 AM CDT/ Tuesday for LSZ162-242-
263.
Gale Warning until 4 AM EDT /3 AM CDT/ Tuesday for LSZ240-241.
Storm Warning until 3 AM EDT Tuesday for LSZ243>250-264>266.
Gale Warning from 3 AM to noon EDT Tuesday for LSZ243-244-264.
Gale Warning from 3 AM to 2 PM EDT Tuesday for LSZ245>250-265-
266.
Gale Warning until 8 AM EDT Tuesday for LSZ251-267.
Lake Michigan...
Gale Warning until 2 PM EDT Tuesday for LMZ221-248-250.
&&
$$
SHORT TERM...TAP
LONG TERM...TAP
AVIATION...07
MARINE...TAP
Area Forecast Discussion
National Weather Service Nashville TN
705 PM CDT Mon May 1 2023
...New UPDATE...
.UPDATE...
Issued at 702 PM CDT Mon May 1 2023
Radar this evening shows some scattered showers and sprinkles
have developed across our northeastern half. This activity is
occurring in association with the main upper level trough axis
moving overhead, which can be seen really well on water vapor
imagery. Have gone ahead and added a slight chance pop for our
northeastern quadrant of the cwa for the rest of the evening in
line with the HRRR and CONSShort models. Otherwise, windy and
cool conditions continue across the midstate, and with dewpoints
now down into the 30s, lows should drop into the 40s areawide
overnight. Made some minor adjustments to temps through tomorrow
but nothing significant. Rest of forecast looks to be on track.
&&
.SHORT TERM...
(This afternoon through Tuesday Night)
Issued at 107 PM CDT Mon May 1 2023
Fairly quiet conditions are still in store through much of this
week. Satellite imagery this afternoon shows an upper-level low
spinning over the Great Lakes region, and this feature will be
very slow to eject towards the northeast. While our weather will
be dry, strong upper-level winds, high mixing heights, and a tight
pressure gradient will keep our winds breezy to locally windy.
These winds will taper off after sunset with the loss of daytime
heating and mixing, but will strengthen again by late Tuesday
morning. These winds still look to remain below Wind Advisory
criteria, but some locations may be close. Otherwise, look for
high temperatures to gradually warm each day as well while staying
several degrees below normal.
&&
.LONG TERM...
(Wednesday through next Monday)
Issued at 107 PM CDT Mon May 1 2023
By Wednesday, the low moves far enough east that our upper-level
flow begins to relax and ridging begins to build over the area.
This should lead to a gorgeous Wednesday and Thursday with
temperatures warming into the upper-60`s and low-70`s with mostly
clear skies and lighter winds. Our next shortwave moves through on
Friday, increasing shower activity across the west by early
morning and then spreading westward as the day progresses. These
off-and-on showers will stick around through each day of the
weekend. Despite being a nuisance to those with plans this
weekend, no hazardous weather with severe weather or flooding is
expected.
Models are in poor agreement in regards to next week. It looks
like another low pressure system will be coming off the Rockies,
but how deep it is and its overall track is currently up in the
air. An minimum, a wet pattern looks to continue early next week,
but it could be a storm system worth watching depending on where
it goes.
&&
.AVIATION...
(00Z TAFS)
Issued at 607 PM CDT Mon May 1 2023
Conditions will remain VFR at all sites over the next 24 hours,
but windy conditions will also be continuing. A tight surface
pressure gradient will keep winds gusting between 20 and 30 knots
out of the west this evening. Gusts should let up overnight, but
will return by mid morning Tuesday. Scattered cumulus are over
most of the area this evening with similar sky conditions expected
tomorrow.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 45 66 45 69 / 10 0 0 0
Clarksville 43 66 42 67 / 10 0 0 0
Crossville 40 59 39 60 / 20 10 0 0
Columbia 42 66 42 68 / 10 0 0 0
Cookeville 40 61 40 62 / 20 10 10 0
Jamestown 40 59 39 61 / 20 10 10 0
Lawrenceburg 40 66 42 67 / 10 0 0 0
Murfreesboro 43 66 42 67 / 10 0 0 0
Waverly 42 65 42 66 / 10 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.......Shamburger
SHORT TERM...Clements
LONG TERM....Clements
AVIATION.....Whitehead