Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/06/25
Area Forecast Discussion
National Weather Service Des Moines IA
534 PM CST Wed Mar 5 2025
...Updated for the 00z Aviation Discussion...
.KEY MESSAGES...
- Strong winds gradually wane late this afternoon and more so
this evening, but blowing snow and difficult travel conditions
remain, especially north, into at least early evening.
- Band of moderate snowfall over central Iowa Thursday night
into Friday. 1" per hour snowfall rates possible, especially
Friday morning. Snow amounts trending towards need for
another winter headline.
- Weekend into early next week turns dry and warmer with highs
pushing 20 degrees above normal. Will need to monitor for
break-up ice jams - see hydrology section.
&&
.DISCUSSION...
Issued at 255 PM CST Wed Mar 5 2025
REST OF TODAY/TONIGHT:
Strong low pressure system has moved northeast of the state early
this afternoon with snow having come to an end by around midday.
Snow amounts with today`s system have been exceptionally hard to
measure, as expected with the winds, but reports have ranged from 1-
8" in a band covering much of west central into north central Iowa,
with lighter amounts to the east. However, impacts remain across
much of the area with many roads partially to fully covered, and a
number of roadways also with `travel not advised` designations per
the Iowa DOT. Area road and plow cameras continue to show snow
blowing across roadways, in some cases causing them to be completely
drifted over, with visibility reductions also remaining at a number
of locations, especially north, with blowing snow ongoing early this
afternoon. With visibilities all improved over 1/4 to 1/2 mile, did
transition the blizzard headline to a Winter Weather Advisory which
remains in effect until 6 PM at this point, though may need to be
extended if blowing snow remains a problem after that time. Will let
next shift evaluate. Regardless, travel impacts will continue in
many areas through the evening commute so caution is certainly
advised.
The strong winds have also started to diminish, especially west and
south, though winds remain quite gusty with gusts of 40-50 mph or
more in areas west and south changed over to a Wind Advisory.
Meanwhile, some near 60 mph gusts have been noted in northeast areas
this afternoon with mixing still quite efficient even though the
pressure gradient itself has started to relax a bit compared to last
night into this morning. A High Wind Warning remains in the
northeast for where these stronger gusts are still ongoing, but both
wind headlines also continue until 6pm at this point. Winds will
gradually decrease through the rest of the evening hours becoming
fairly light overnight into Thursday as a quick surface ridge moves
through the area. This will ultimately mean a quiet night for us in
central Iowa, however the calm winds, surface ridge, and fresh
snowpack will lead to more efficient cooling as skies continue to
clear west to east tonight. This translates to low temperatures
tonight back in the teens to 20s with the lowest temperatures west
to north where radiational cooling is likely to be more
efficient.
THURSDAY AND BEYOND:
The wave analyzed this morning over Montana at 850mb
will dive southeast along the northwest flow into the state by
midday Thursday. Meanwhile, thanks to the influence of an inbound
longwave trough in the Rockies, lee cyclogenesis will commence and
continue to churn moisture up into the Upper Mississippi Valley.
Strong isentropic ascent ramps moisture into the state. In regards
to the first minor wave, soundings insist on delaying boundary
layer saturation until late Thursday evening, so precipitation
chances remain low for that first wave. This is due to its
projected weakening as it arrives in Iowa. However, this wave
will have implications on high temperatures Thursday, affecting
the temperature profile for the precipitation later in the
evening. 12z deterministic guidance also lowers the bar further
as it ingests snow depth from the blizzard last night, holding
temperatures near freezing across west central and northern Iowa
(NAM being an outlier at this time due to outlier surface
temperatures). This then sets the stage for the surface cyclone
passing to the south, its frontogenetical zone producing all
snow north. The far south will be warm enough to have rain for
the majority of the event.
So, what does this all mean for the forecast? Firstly, temperatures
are lowered below NBM guidance in the north and west. This also
means that higher SLRs continue to be supported. Have raised them to
where at least 13:1 SLRs are found north of I-80. Snowfall amounts
of 4-6 inches are expected across north central Iowa, so north of I-
80 and up to just north of Highway 20. Some more confidence boosters
come from what`s evident in cross sections and soundings. The cross
sections have an overlap of CSI, frontogenesis, and -15 microbars of
lift in the dgz. Upon sampling parcel path in soundings from the RAP
and GFS, there is some CAPE present in the DGZ. All these signals
point to high snowfall rates and localized amounts exceeding what is
forecasted currently. With wind gusts up to around 20-25mph, blowing
and drifting snow will be a possibility, but thankfully not to the
magnitude found today. Headlines will be needed and will be issued
once the current winter storm concludes.
In the extended, an upper level closed low will favor a more
southern stream pathway, locking us in northwesterly to zonal
flow through the weekend. An upper level ridge will follow and
bring above normal temperatures back into the picture to start
next week. However, we will have to watch two systems moving
nearby. The first of which will be midweek, the second of which
at the end of next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 528 PM CST Wed Mar 5 2025
Flight conditions continue to steadily improve this evening,
with the MVFR cloud deck departing to the east and giving way
to clear skies early this evening. Strong northwesterly winds
remain, but are diminishing as well, especially in the west.
Expect this trend to continue into the evening as the sun goes
down and winds taper off from west to east. As a result of diminishing
winds, visibility reductions due to blowing snow will be coming
to an end. Winds become light and more westerly by tomorrow,
with VFR conditions prevailing through the day on Thursday.
&&
.HYDROLOGY...
Issued at 255 PM CST Wed Mar 5 2025
Main hydrologic concerns will shift to break-up ice jam potential
especially this weekend into next week. Snowmelt runoff from the new
snowpack as well as from more potential snow later this week will
add more water to area streams thus increasing the potential for ice
break-up. Localized flooding from any break-up ice jams will be
possible (30% confidence overall). The most likely areas to
experience issues would be those areas that have historically
experienced ice jam flooding. River stages may fluctuate rapidly
and in localized areas in response to any ice activity.
In the shorter term, although no flash flooding occurred from the
seasonally moderate to heavy rainfall which occurred from yesterday
through last night, some ponding did occur especially in urban
areas. Also, mostly moderate within-bank rises occurred on area
streams as well. Some smaller streams have already peaked in their
responses and are on their way back down. Other streams will take
longer to trend toward pre-event levels.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 6 PM CST this evening for IAZ004-005-015-
023-024-033>035-044>046-057>059-070>075-081>086-092>097.
Winter Weather Advisory until 6 PM CST this evening for
IAZ004>007-015>017-023>028-033>039-044>050-057>062.
High Wind Warning until 6 PM CST this evening for IAZ006-007-
016-017-025>028-036>039-047>050-060>062.
&&
$$
DISCUSSION...KCM/Jimenez
AVIATION...Dodson
HYDROLOGY...Zogg
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
708 PM EST Wed Mar 5 2025
.KEY MESSAGES...
- Wind advisory overnight into Thursday afternoon for northwest winds
gusting around 45 mph, particularly in the 5-10 AM Thursday morning
time frame.
- Temperatures drop from the upper 40s-lower 50s this evening to the
upper 20s by the Thursday morning commute. Standing water will
likely freeze, leading to potential icy spots for the Thursday
morning commute. In addition, light snow accumulating less than 1
inch will likely occur over the northern half of the CWA tonight.
- Minor accumulating snow possible on Friday south of M-59.
&&
.AVIATION...
Convective showers continue to stream north across the terminals
this evening with the Metro terminals (PTK south) better positioned
for reoccurring showers that feature gusty winds and MVFR ceilings.
This pattern persists until late evening as the governing low`s
reservoir of cold air spills in from the southwest brining a brief
reduction in ceiling heights to near IFR. Precipitation type
concerns arise overnight as the column cools aggressively and
introduces potential for ice nuclei aloft. Expect a period of
showers composed of a rain/snow mix for most sites before changing
over to just light snow for a few hours Thursday morning. Meanwhile,
a nocturnal mixed-layer arises due to low-level cold air advection
that provides renewed gusty flow, tapping into 35+ knot winds in the
lowest 4 kft AGL. This turbulent layer continues through the midday
hours, increasing with time as surface flow veers toward 300 degrees
and the low-level jet maximizes overhead. North-south oriented
runways will likely be impacted by strong crosswinds.
For DTW...Some additional gusty convective rain showers this
evening. P-type changes over to rain/snow mix after midnight, then
just snow early Thursday morning. Winds from 300-310 degrees for
most of Thursday with gusts up to 40 knots possible.
.DTW THRESHOLD PROBABILITIES...
* High in ceiling at or below 5000 feet tonight until early
afternoon Thursday.
* High in precipitation type as rain this evening, then
transitioning to a rain/snow mix overnight before becoming all
snow early Thursday morning.
* High in crosswind exceedence Thursday.
* Low in thunder through 05Z this evening.
&&
.PREV DISCUSSION...
Issued at 308 PM EST Wed Mar 5 2025
DISCUSSION...
Highly amplified upper level flow over North America, with multiple
vortices rotating about the strong and deep low pressure system over
the Great Lakes region. This system has pretty much bottomed out and
looks to hold steady or slowly fill tonight, as model consensus is
for the surface low (982-984 MB) to track through northern Lake
Huron/Georgian Bay. Winds gusting to 40 MPH this afternoon in the
warm sector with temperatures in the mid to upper 50s. The slight
thunderstorm chance is just about to end shortly as the occlusion
has exited east and surface base capes mainly aob 250 J/kg now.
Winds will diminish a bit this evening before a cold front crosses
southeast Michigan late in the evening/by midnight, with then
stellar cold advection kicking in, lowering 850 MB temps to
-10 to -12 C by around 12z Thursday. As far as the snow goes
tonight, deformation/modest wrap-around moisture looks fairly short
lived tonight, and with lift/saturation mainly below the DGZ,
accumulations look to be less than 1 inch. However, with surface
temperatures falling into the upper 20s by the Thursday morning
commute, there could be some icy spots on untreated roads from
residual standing water. As far as wind goes, boundary layer depths
look to approach 850 MB Thursday morning, and with 12z HRRR/NAM/15z
Rap all indicating 50 knots of flow, have elected to issue a wind
advisory (7-21z) for wind gusts around 45 mph, peaking in the 5 AM -
10 AM window. Despite the cold airmass, late afternoon early March
insolation should allow temps to respond back into the mid to upper
30s.
500 MB low over Central Canada will be approaching the northern
Great Lakes on Friday. Strong west-northwest upper level confluent
flow over Lower Michigan will attempt to deflect the weakening storm
system coming out of the Central Plains. It is none-the-less a close
call toward the southern Michigan border with the tight baroclinic
zone in place, as the 500 MB shortwave coming out of the Midwest may
be just strong enough. With 850 MB temps aob -6 C, precip would
likely fall mostly as snow. A light snow accumulation is thus
possible for areas south of M-59. Euro ensembles indicating a 10-40
percent chance of qpf aoa a tenth of an inch for areas along the
southern Michigan border to the I-94 corridor. Even if this was to
occur, with surface temps solidly above freezing during the day,
would expect main roads to be just wet.
One more shortwave embedded in the northwest flow to track through
late Saturday before heights begin to build with a large upper level
ridge encompassing the central Conus early next week supporting a
big warm up. With increasing low level southwest flow and 925 MB
temps progged to reach in the low to mid teens on Tuesday, per 12z
Euro, temps well into the 60s appear likely.
MARINE...
The center of strong low pressure is now over Grand Traverse Bay,
producing scattered showers and isolated storms this afternoon with
southerly winds gusting mainly in the 20 to 25 knot range. A brief
lull in winds will occur as the low center tracks over northern Lake
Huron this evening. As the system begins to move into Georgian Bay
and Ontario around and after midnight, strong cold advection will
commence and spread southeast through the early morning. Deep mixing
into a layer of stronger winds aloft will bring northwest gales
across Lake Huron late tonight through Thursday and a Gale Warning
remains in effect. A Heavy Freezing Spray Warning is also in effect
for northern and central Lake Huron. Rain will transition to snow
after midnight and continue through the morning before tapering off
midday tomorrow. Gales subside by Thursday evening, but moderate
west to northwest flow of 20 to 25 knots will persist through the
end of the week.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...Wind Advisory from 2 AM to 3 PM EST Thursday for MIZ047>049-053>055-
060>063-068>070-075-076-082-083.
Lake Huron...Gale Warning from 2 AM to 10 PM EST Thursday for LHZ361>363-442-443-
462>464.
Heavy Freezing Spray Warning from 2 AM to 4 PM EST Thursday for
LHZ361-362.
Gale Warning from 2 AM to 4 PM EST Thursday for LHZ421-422-441.
Lake St Clair...None.
Michigan waters of Lake Erie...Small Craft Advisory until 10 PM EST Thursday for LEZ444.
&&
$$
AVIATION.....KGK
DISCUSSION...SF
MARINE.......TF
You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.
Area Forecast Discussion
National Weather Service Grand Rapids MI
858 PM EST Wed Mar 5 2025
.KEY MESSAGES...
- Very windy tonight/Thu morning with rain changing to snow
- Cooler Fri-Sun with a couple small chances of precipitation
- Mainly dry and increasingly warmer next week
&&
.UPDATE...
Issued at 859 PM EST Wed Mar 5 2025
Strong northwesterly winds are working their way into the area.
Muskegon County Airport gusted to 52 mph in the past hour. The
strongest gusts up to 55 mph are expected along the lakeshore with
45 mph gusts inland. Wind will gradually weaken Thursday morning.
As the night goes on, snow will focus more along the lakeshore
with 1-3 inches expected with the highest amounts in Allegan and
Van Buren counties. Farther inland amounts of an inch or less are
expected.
&&
.DISCUSSION...
Issued at 311 PM EST Wed Mar 5 2025
- Very windy tonight/Thu morning with rain changing to snow
We will be expanding the Wind Advisory from just the lakeshore, to
the remainder of the forecast area from 10 pm this evening through
noon on Thursday.
The last couple of sets of synoptic model data, and short term model
data like the SREF and HRRR support wind gusts around 45 mph for
just about all of the inland areas beginning toward midnight
tonight, and lasting into the first part of Thursday morning. The
winds along the lakeshore will pick up a little earlier, and the
starting time for their advisory looks good. Forecast soundings from
various model sets show 40 knots of wind as low as 1k ft agl, which
should be able to be mixed down easily with the strong cold air
advection on the backside of the system.
The arrival of the wind with the colder air will also change
residual rain showers this afternoon and early evening to light
snow/snow showers for the overnight hours. The snow shower activity
will be focused near the lakeshore with some lake enhancement.
However all areas will likely see some light snow before the
deformation precipitation on the back side of the system completely
moves out.
We are not expecting lake effect to be anything more than a few
slick spots on the roads and light accums on grassy areas for any
location. Road sfcs are in the upper 40s to lower 50s, so it will
take a while for them to cool as sfc temps are forecast to drop to
around freezing toward daybreak.
As far as lake effect chances are concerned, 850 mb temps are
forecast to drop to around -12C, giving delta t`s of around 14-15C.
The deeper moisture will be peeling away fairly quick for the second
half of the night, and inversion heights will drop to below 5k ft
agl by morning. Any showers will wind down Thursday morning as the
upper shear axis/jet core lifts NE out of the area.
- Cooler Fri-Sun with a couple small chances of precipitation
The weekend is looking mainly dry and cool for the period, but there
will be multiple chances of some light precipitation.
We will remain under the influence of NW flow aloft through the
weekend. This will allow the cooler air to hold in for this period.
What it will also do is allow two or three weaker short waves to
either clip, or pass right through the area. These waves will not
have really any moisture to work with, and temperatures aloft will
not be cold enough for any kind of noticeable lake effect as 850 mb
temps are forecast to stay mainly warmer than -10C.
- Mainly dry and increasingly warmer next week
Once the final wave in the series for the weekend moves by just
north of the area on Sunday, we will see a fairly broad area of high
pressure aloft slowly build toward the area.
This ridge will bring fairly strong subsidence to the area, likely
allowing for some sunshine for at least Monday and Tuesday. This
ridge will also help to bring much warmer temperatures to the area.
850 mb temps will warm up to almost +10C by next Tuesday. If this
comes to fruition, 60s will be likely by then.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 652 PM EST Wed Mar 5 2025
IFR ceilings and/or visibility is becoming more common for at
least the next few hours as rain changes to snow on the back side
of this strong low-pressure weather system. Later tonight, MVFR
ceilings will become more common, and MVFR to IFR visibilities
will occur within lake-enhanced snow showers, most frequently near
Lake Michigan. Winds becoming northwest tonight will gust 30 to 40
knots. Wind speeds gradually relax but stay gusty on Thursday. By
afternoon, the MVFR clouds are favored scatter out to VFR, though
the HRRR is currently the odd model out that maintains ceilings.
&&
.MARINE...
Issued at 311 PM EST Wed Mar 5 2025
Gales are a certainty tonight and Thursday morning as the colder air
rushes in on the backside of the system over the region today. In
fact, a few Storm Force wind gusts may be briefly possible tonight
as the cold air arrives. The duration and confidence of Storm Force
winds are not high enough to upgrade at this time. Winds will come
down below Gales Thursday morning.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Wind Advisory until 7 AM EST Thursday for MIZ037-043-050-056-064-
071.
Wind Advisory until noon EST Thursday for MIZ038>040-044>046-051-
052-057>059-065>067-072>074.
MARINE...Gale Warning until 10 AM EST Thursday for LMZ844>849.
&&
$$
UPDATE...RAH
DISCUSSION...NJJ
AVIATION...CAS
MARINE...NJJ
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
922 PM CST Wed Mar 5 2025
.KEY MESSAGES...
- A band of snow crossing northern Illinois and northwest
Indiana this afternoon may result in some slippery spots on
roads through early evening.
- A Wind Advisory is in effect areawide this afternoon and
evening. A Lakeshore Flood Advisory is in effect for Lake and
Porter counties in IN this evening.
- Snow and/or rain expected across the area on Friday. A
corridor of wet snow accumulation is expected across portions
of northern Illinois and northwest Indiana.
- Spring-like warmth expected early next week.
&&
.UPDATE...
Issued at 922 PM CST Wed Mar 5 2025
No significant changes made to going forecast, with current
Wind Advisories and Lakeshore Flood Advisories remaining in
effect.
Surface low pressure of 983 mb was analyzed over Lake
Huron/Georgian Bay at mid-evening, moving slowly east-northeast
into southern Ontario. Strong pressure and isallobaric (6-7 mb
rises in 3 hours) gradients persist in the wake of the low
across WI/IL/LM and IN, with surface wind gusts still peaking in
the 45 mph range across northeast IL/northwest IN. Gusts have
eased a bit into the 35-40 mph range south of I-80, though RAP
forecast soundings still support the potential for sporadic
gusts near 45 mph there as well. With no change to the message
with respect to winds, have maintained Wind Advisory and Lake
Shore Flood Advisory headlines as is, with winds expected to
only gradually diminish overnight.
Regional radar mosaic depicts persistent light snow/snow
showers generally along/east of about a Harvard to Gibson City
IL line as of 9 pm, in association with additional mid-level
DPVA within the trailing portion of the parent mid-level trough.
This area of light snow showers will continue to move to the
east over the next few hours, diminishing to isolated flurries
and eventually ending overnight from west to east as substantial
subsidence develops and breaks up and erodes the low-level
stratus deck which lingers across the Mississippi Valley. Can`t
rule out a couple of tenths of additional snow accumulation
mainly east of the IL/IN state line through midnight or so,
with no additional accumulation expected over northern IL. The
exception to this may be northeast Porter county where some
lake-effect/enhancement may produce up to an additional inch,
though rapidly lowering inversion heights and strong low-level
drying will work increasingly against this after midnight.
Otherwise, cloud cover will eventually decrease from west to
east late tonight.
Ratzer
&&
.DISCUSSION...
Issued at 349 PM CST Wed Mar 5 2025
Through Thursday:
A band of precipitation along and behind a sharpening cold
front across southern Wisconsin into northern Illinois has
mostly switched over from rain to snow as it nears the Chicago
metro as of 2pm. Though deep-layer forcing from the passing mid-
level trough axis will quickly shift east over the next several
hours, most locations across northern Illinois into northwest
Indiana will see an approximately three hour window of light to
briefly moderate snow through early evening. Slushy
accumulations up to 1 inch across the northwest CWA and a half
inch for the Chicago metro are possible during this time. With
temps falling below freezing, some slippery spots are possible
on area roadways.
With the surface low now shifting northeast across southern
Lake Michigan this afternoon, strong northwest winds have
started to spread across much of the forecast area. Significant
pressure rises this afternoon into early evening combined with
stout CAA will continue to support frequent northwest gusts of
45-50 mph through at least mid-evening. Winds will then steadily
ease overnight through Thursday, though blustery conditions
with gusts to 30 mph will be prevalent during the morning.
No changes have been made to the Wind Advisory across the
entire forecast area and Lakeshore Flood Advisory along the
Indiana shore with this forecast.
Drier air will begin advecting across the area from the
northwest later this evening and overnight as inversion heights
gradually lower. Lingering scattered snow showers this evening
should either fully dissipate or transition to flurries as the
remaining stratus deck thins under the inversion. Some shallow
stratus may persist through daybreak Thursday, but expectations
are for mostly sunny skies for much of the day with some cirrus
filtering in from the west late in the day.
Kluber
Thursday Night through Tuesday:
Late Thursday night into Friday, a shortwave trough will track
eastward from the central Plains into the southern Great Lakes,
flattening and shearing out in the process. At the surface, a
compact and weakening surface low will track across the Lower
Missouri River Valley into the Ohio River Valley with a narrow,
but elongated band of precipitation flanking it to its north.
Forecast guidance is in nearly unanimous agreement on this
precipitation band affecting our forecast area, but there is
still a non-insignificant spread in both the width of the band
and where the core of it will set up shop -- both of which are
critical details for how Friday`s weather will pan out as dry
air to our north will be pressing southward and will likely
result in a sharp cut-off to the precipitation somewhere across
southern Wisconsin or northern Illinois.
Air temperatures are expected to range from the low 30s to the
low 40s over the duration of this precipitation event, coldest
farther north and mildest farther south. This means that both
rain and snow will be possible precipitation types, with snow
generally more likely farther north and rain generally more
likely farther south. Such temperatures will likely require snow
to fall at a decent rate in order for anything more than a
dusting or light coating of snow accumulation to be realized,
and with model guidance suggesting that the mid-level
frontogenesis powering this precipitation band should be fairly
robust, resulting in fairly steep lapse rates and formidable
ascent through the dendritic growth zone (at least for a few
hours), such rates appear to be achievable.
However, with the weakening nature of the shortwave and surface
low, large-scale forcing for ascent away from the stronger
frontogenetical circulations may not be strong enough on its own
to churn snow out at a steady enough clip to overcome the
marginal surface temperatures and produce much of any snow
accumulations. Thus, the current expectation is for most of the
snow accumulation here to occur across a narrow corridor whose
precise placement likely won`t be able to be pinned down until
we are able to see how radar trends are unfolding upstream. The
expected wet/low snow-to-liquid ratio type of snow should tend
to temper overall snow amounts, but the relatively long duration
of the precipitation (from early Friday morning through Friday
evening) should help compensate for that and allow for some
locations to pick up an inch or more of snow if the progged
frontogenesis pans out more or less as advertised.
Over the weekend, an upper-level ridge will become established
over the western CONUS, resulting in northwest flow aloft over
the Midwest. One upper-level shortwave embedded in this
northwest flow will pass close by late Saturday/early Sunday and
could bring an additional period of flurries or light snow to
the region. However, with most of the latest ensemble guidance
keeping any measurable precipitation with this wave to our north
and northeast, and with forecast soundings showing that there
will be a good bit of dry low- to mid-level air to work through
here, have maintained a dry forecast for this time period as
output by the NBM.
Early next week, the western CONUS ridge will slide eastward,
while the surface pressure configuration will generally promote
southerly winds and warm air advection across the central CONUS.
While there are still some finer-scale uncertainties that will
need to be ironed out over the coming the days (including the
influence of the still-cold Lake Michigan and how far north any
warm fronts will surge), on the whole, the first half of next
week looks very much spring-like with widespread 60+ degree
temperatures likely to make an appearance in the area. With a
longwave trough replacing the ridge out west, there is a fairly
strong signal in ensemble guidance for lee cyclogenesis
occurring in the Plains next week. Whatever comes of that will
likely lead to our next precipitation chances sometime in the
Wednesday to Thursday time frame.
Ogorek
&&
.AVIATION /00Z TAFS THROUGH 06Z FRIDAY/...
Issued at 521 PM CST Wed Mar 5 2025
The main aviation weather concerns for the 00Z TAF period
include:
* Gusty NW winds this evening and tonight.
* MVFR cigs through the night and into early Thursday.
* Occasional flurries or light snow showers possible this
evening.
The snow showers falling on the Chicagoland sites late this
afternoon will be off to the east by 00Z. A few additional
flurries or light snow showers may materialize this evening, but
we should be largely precip-free after dark. NW winds will gust
to around 40 kt for the better part of this evening and between
30 and 35 kt overnight. Winds will remain NW and very gradually
subside during the day on Thursday. Finally, MVFR cigs will
remain through the night and are expected to scatter out in the
early-mid morning on Thursday. VFR conditions are then expected
during rest of Thursday.
Doom
&&
.MARINE...
Issued at 203 PM CST Wed Mar 5 2025
A strong mid-latitude cyclone currently crossing southern Lake
Michigan will result in a period of northwest gales to 45 knots
through early Thursday morning. A few storm force gusts in
excess of 50 knots may occur as well, especially east of Gary
and on high-platform observation stations. A Gale Warning
remains in effect for the Illinois and Indiana nearshore waters
of Lake Michigan.
NWS Chicago
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Wind 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...Lakeshore Flood Advisory until 6 AM CST Thursday for INZ001-
INZ002.
Wind Advisory until 3 AM CST /4 AM EST/ Thursday for INZ001-
INZ002-INZ010-INZ011-INZ019.
LM...Gale Warning until 6 AM CST Thursday for the IL and IN
nearshore waters.
&&
$$
Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Marquette MI
746 PM EST Wed Mar 5 2025
.KEY MESSAGES...
- Dangerous travel conditions continue past midnight tonight,
especially Baraga/Marquette and points east, with reduced visibility
due to a combination of falling and blowing snow.
- An additional 2-5" from 8 pm through the rest of the night for
the western UP and Baraga/Marquette/Alger. Up to 2" elsewhere.
- Strong winds up to 45 mph (strongest in the Keweenaw and Lake
Superior counties) will continue to result in whiteout conditions,
possible tree damage, and potential for power outages. Winds will
gradually decrease after midnight.
&&
.UPDATE...
Issued at 745 PM EST Wed Mar 5 2025
Dangerous travel conditions continue past midnight tonight,
especially Baraga/Marquette and points east.
As of 730 pm EST, 984 mb low analyzed over far NE Lower. Dominant,
nearly steady-state 925-700mb fgen band over the north-central UP
has started to shift east and break down somewhat, with steadiest
snow over Alger and Delta. However pure lake effect with upslope
enhancement is noted over Marquette and Baraga Counties as 850 mb
temps fall to around -13C and inversion heights up around 5kft. This
will prolong the snowfall with around 2-4" additional through 06Z
for these areas as well as east to Alger and over the western UP as
well. Winds continue to be impressive especially in the central and
east, with gusts of 30-40kt. So dangerous travel conditions continue
past midnight tonight, especially Baraga/Marquette and points east,
before gradually improving for the remainder of the night. Extended
the Winter Storm Warning for Iron/Dickinson through 06Z due to a
combination of lingering falling and blowing snow. Also added
southern Schoolcraft to the Winter Weather Advisory through 06Z as
they will see a couple hours of decent snowfall rates and reduced
vsby due to blowing snow.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 251 PM EST Wed Mar 5 2025
RAP analysis reveals deep 982mb low pressure is moving across the
northern Lower Peninsula this afternoon, with a surface front
stalled out just south of the UP. Of note on water vapor sounding is
a dry sector nosing into the far eastern UP. This may be cutting
into our precip rates out there, but out ahead of it in the central
and western UP, strong deformation continues to lead to moderate to
occasionally heavy embedded snow banding. Snow is turning fluffier
across the western UP with surface temperatures in the lower/mid 20s
and model soundings already turning quite cool with the top of the
inversion height reaching into the DGZ. Across the central UP,
however, snow is still on the wetter side with a much warmer (though
still subfreezing) column. In the far eastern UP, temperatures
remain warm enough that rain is occasionally mixing in with snow. In
any heavier banding, snowfall rates in excess of 1in/hr will be
possible, with the heaviest snowfall rates (potentially up to 1-
2in/hr) still looking to be across the higher terrain of the western
and north-central UP courtesy of orographic enhancement amid
blustery northerly winds. Between now and 00Z, this may lead to as
much as another 6-8in in northern Marquette and Baraga counties with
a widespread 3-6in elsewhere across the warned areas. Still, there
is a "bust" potential as SLRs so far have come in slightly lower
than expected this afternoon.
Otherwise, 30-40mph wind gusts are becoming more common across the
UP this afternoon, with even higher gusts up to 50mph possible along
the Superior shoreline. This is leading to areas of blowing and
drifting snow, and blizzard-like conditions at times as many sites
throughout the UP are reporting persistent visibility of a half
mile or lower.
The surface low continues to make an exit over Lake Huron tonight,
and as we gradually lose out on strong dynamical support, snowfall
rates will slowly fall back with another few inches of fluffier snow
possible before midnight. After 06Z, light lake effect snow will
linger in the NNW Wind snow belts with amounts peaking at around 1-
2in. While winds should slowly fall back from west to east tonight,
winds still remain elevated enough that blowing snow remains a
concern. Otherwise, expect temperatures to quickly drop back into
the teens across most of the UP tonight.
With at least several more inches of snow expected the rest of this
afternoon to around midnight as well as blizzard-like conditions,
will allow the winter headlines to continue.
&&
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
Issued at 353 PM EST Wed Mar 5 2025
Lingering LES showers over E Upper MI Thu morning supported by
cyclonic flow and marginal Lake Superior sfc-850mb delta-ts
diminishes through the morning as warmer air and drier air advects
in from the W. A weak clipper drops SE from far NW Ontario Thu
morning toward S Ontario by Fri morning. This kicks up a light round
of snow progressing W to E Thu afternoon and evening. With weak
forcing, limited moisture and sparse coverage, accumulations will be
limited to a few tenths at best and no impacts are expected.
Otherwise highs are expected in the upper 20s to upper 30s.
With 850mb temps dropping down to between -14C and -20C (colder over
the NE portion of Lake Superior) behind the shortwave, trailing LES
over the NW wind snow belts of E Upper MI is possible through Fri
night. With delta-ts only decreasing Fri night onward and model
sounding showing a lack of low level moisture, coverage likely will
gradually diminish into Sat. Light and fluffy accumulations of up to
1-2" are possible by Sat morning, but most will see less than 0.5"
of snow with no impacts. Lows Thu night are expected mainly in the
teens with highs on Fri in the mid 20s to mid 30s. Weak sfc ridging
briefly extending over the UP Fri night will allow for some
radiative cooling to bring lows into the single digits above 0F in
the west, elsewhere should expect lows in the low to mid teens.
A shortwave on Sat may bring another light round of snow overnight
into Sun, but better chances hold off until Sun as a deeper
shortwave and associated clipper low track over N Ontario. There
still is a significant spread in sfc low track with this system, so
accumulation amounts will depend on where the system ends up
tracking. Currently there is a 15-30% chance over the N tier of
Upper MI for 1"/24hr with this system. Will monitor trends with
future fcst packages, however impacts are not expected at this time.
This pattern almost repeats perfectly Mon night through Tue, however
probabilities for 1"/24hr are even less with this system as a
further N track is favored. Drier weather is favored into mid next
week as temps warm well above normal with mid level ridging over the
W CONUS tracks E over the CONUS and flattens out. Highs Mon-Wed are
expected in the 40s with some 50s possible on Tue.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 617 PM EST Wed Mar 5 2025
Winter storm continues to bring whiteout conditions and strong winds
to the terminals early on due to a combination of snow and blowing
snow. Gradual improvement is expected through the night into the day
Thursday as the system moves out. Expect LIFR to occasional below
airport min vsby at CMX/SAW for the first 1-3 hours of the TAF
period before gradually improving to IFR and then MVFR late tonight.
IWD will improve a little faster from IFR to MVFR. Northerly winds
will continue to gust near 40 kt at SAW/CMX for the first part of
the night before gradually decreasing to 25-30 kt by morning. Winds
have already decreased below 30 kt at IWD, but northerly gusts to 25
kt can be expected at times through the night.
&&
.MARINE...
Issued at 251 PM EST Wed Mar 5 2025
Northerly high-end gales to 40-45 kts across much of the lake this
afternoon continue into this evening as a strong low pressure tracks
over northern Lower Michigan and Lake Huron. The strongest winds are
expected over the east half of the lake where a few storm force
gusts to 50 kts are possible (~50% chance). Winds gradually back
northwest tonight through Thursday morning and eventually west by
Thursday afternoon as the low pressure continues northeast to
Quebec. Winds over the western third of the lake fall below gales
around midnight tonight while the middle third of the lake falls
below gales by sunrise. Some gales to 34 kts are likely to linger on
through late Thursday morning over the eastern third of the lake.
Through Thursday morning, moderate to occasionally heavy freezing
spray is expected. Peak wave heights are expected through this
evening around 15-20ft with the highest waves over the southern half
of the lake, particularly near the Keweenaw.
West winds 20-30 kts Thursday afternoon veer northwest Thursday
evening, continuing northwest 20-30 through much of the day Friday
as a weak clipper system moves overhead. Northwest winds settle to
20 kts or less Friday night remaining less than 20 kts through
Saturday night out of the west. Westerly winds of 15-25 kts are
likely on Sunday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Blizzard Warning until 1 AM EST Thursday for MIZ001>006-084.
Lakeshore Flood Advisory until 1 AM EST Thursday for
MIZ001>003.
Lakeshore Flood Advisory until 7 AM EST Thursday for MIZ005-
006.
Winter Weather Advisory until 4 AM EST Thursday for MIZ007-085.
Winter Storm Warning until midnight CST tonight for MIZ009>011.
Winter Weather Advisory until 1 AM EST /midnight CST/ Thursday
for MIZ012>014.
Lake Superior...
Gale Warning until 7 AM EST /6 AM CST/ Thursday for LSZ240>244-
263-264.
Gale Warning until 10 PM EST /9 PM CST/ this evening for
LSZ162.
Gale Warning until 1 PM EST Thursday for LSZ245>251-265>267.
Lake Michigan...
Gale Warning until 7 AM EST Thursday for LMZ248-250.
&&
$$
UPDATE...Thompson
SHORT TERM...LC
LONG TERM...Jablonski
AVIATION...Thompson
MARINE...Jablonski
Area Forecast Discussion
National Weather Service San Francisco CA
718 PM PST Wed Mar 5 2025
...New UPDATE...
.SYNOPSIS...
Issued at 120 PM PST Wed Mar 5 2025
Isolated to scattered rain showers are expected tonight into
Thursday morning before diminish by Thursday evening. Dry
conditions and a slight warming trend returns for the upcoming
weekend. Unsettled conditions return by next week with periods of
wet weather continuing potentially into late week.
&&
.UPDATE...
Issued at 706 PM PST Wed Mar 5 2025
After a break this evening, showers will return overnight and
continue through Thursday morning. The 00Z sounding found a sharp
tropopause fold. From the 12Z to 00Z soundings, the tropopause
dropped from 250 mb to 400 mb, bringing in much drier air that
helped shut off the precipitation behind the cold front. This dry
air is now being modified by more moisture from the Eastern
Pacific, while the high 6.8-7.0 C/km lapse rates remain. The
latest WPC prog charts show a new occluded front will develop over
the Bay Area late Thursday morning, which will provide a trigger
for stronger showers and potential thunderstorms. The best chance
for storms tonight is over the coastal waters, where the SST is
around 53 degrees. This will provide more low-level instability
than the cooling land areas. HRRR brings the surface CAPE to 450
J/kg over the Monterey Bay around mid-night, while it stays less
than 200 J/kg over land areas, with temperatures dropping into
the low 40s and a shallow inversion developing.
&&
.SHORT TERM...
(This evening through Thursday)
Issued at 120 PM PST Wed Mar 5 2025
Light to occasionally moderate rain persists over the Central Coast
this afternoon with minimal impacts. This rain will being to
diminish later this afternoon and evening as the frontal boundary
diminishes and weakens. Temperatures this afternoon will be warmest
across the North Bay with mid 50s to lower 60s and mid 50s across
the rest of the region (aside from 40s in the higher elevations).
Tonight and into Thursday morning we will see isolated to scattered
rain showers and possibly isolated thunderstorms (10-20% chance) as
the colder air mass arrives and creates a more unstable atmosphere.
Any thunderstorms or heavier rain showers will be capable of
producing small hail and brief heavy downpours. In addition, we are
expecting snow to fall in the region`s highest peaks, especially
those in the higher terrain of the Central Coast as snow levels drop
to as low as 3,000 feet. Rain/snow showers will diminish Thursday
afternoon and more so into the evening. Temperature for tomorrow
afternoon will be similar to those today region wide, yet slightly
cooler for the higher elevations.
&&
.LONG TERM...
(Thursday night through next Tuesday)
Issued at 120 PM PST Wed Mar 5 2025
Dry and mostly sunny/clear conditions return on Friday and will
continue through much of the weekend as a shortwave ridge builds in
across the region. By Saturday and/or Sunday, the warmest interior
spots will reach up to 70 degrees with low-to-upper 60s elsewhere.
Over the weekend, with clear skies and light winds, expect overnight
lows the be in the mid 30s to mid 40s.
Rain looks to make a return late Sunday with periods of light to
moderate rain continuing at least into the middle of next week. The
rainfall next week looks to be more impactful at this time, yet
details remain difficult to nail down this far out. Be sure to keep
checking back for additional updates!
&&
.AVIATION...
(00Z TAFS)
Issued at 343 PM PST Wed Mar 5 2025
After the cold front passage this morning, the main band of rain
has moved into southern California. Strong westerly winds will
continue through the afternoon today. After a break in
precipitation this evening, scattered showers will return
overnight and continue through Thursday morning. With cold air
aloft, there is a slight chance some of these showers could be be
strong enough to become thunderstorms. Icing conditions will also
exist in these cold clouds. Conditions will gradually improve
through the day Thursday with less shower coverage and more sun
breaks.
Vicinity of SFO...Higher clouds associated with the cold front
will soon clear out, with windy VFR conditions expected through
the evening. Overnight, scattered showers will move in from the
west, with possible brief impacts to SFO and OAK, and likely
impacts to SJC through Thursday afternoon. Otherwise strong
westerly winds will continue this afternoon before decreasing
overnight.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...FEW to SCT low to mid-level clouds are
expected this afternoon, with more impactful showers moving in
overnight. The Monterey Bay Terminals have the best chance at
seeing thunderstorm development Thursday.
&&
.MARINE...
(Today through Monday)
Issued at 1011 AM PST Wed Mar 5 2025
A fresh northwesterly breeze and moderate seas will prevail today.
Showers will continue through tomorrow. There`s a slight chance
for thunderstorms tomorrow with the primary hazards being locally
heavy rainfall and gusty winds, lightning, and small hail. A
strong northwesterly breeze and rough to very rough seas will
prevail Thursday and Friday. Moderate seas and winds are expected
Saturday before building and increasing respectively Sunday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 AM PST Thursday for Mry Bay-SF Bay
N of Bay Bridge.
Small Craft Advisory until 3 AM PST Friday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt
Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt
Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory until 9 PM PST Thursday for Pigeon Pt to Pt
Pinos 0-10 nm.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Flynn
MARINE...Canepa
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Area Forecast Discussion
National Weather Service Pocatello ID
214 PM MST Wed Mar 5 2025
.SHORT TERM...Tonight and Thursday
Afternoon satellite imagery shows cloud cover beginning to
increase as a developing area of low pressure moves across the
Great Basin and is poised to impact eastern Idaho beginning later
this evening. Trying to forecast impacts has been mildly
frustrating to say the least and this is a VERY LOW confidence
forecast as each model run shows slightly different scenarios
which will have much bigger impacts on how things transpire.
Bottom line up front, there have been NO changes to the Winter
Weather headlines given the great amount of uncertainty that still
continues. The latest forecast snow amounts are slightly higher
or lower depending on one`s location. Flirted with upgrading to a
Winter Storm Warning across the Arco Desert where the latest
forecast shows potential for warning level snowfall but NBM
probabilities of reaching criteria are MUCH lower compared to
those of the HREF suite and I just don`t have a feel for which
model solution(s) will win out. Latest 18Z runs of the HRRR and
NAM have higher snowfall totals compared to their 12Z
counterparts, including in the lower valleys of the Snake River
Plain and Magic Valley. Thermal profiles certainly support at
least a rain/snow mix (if not all rain) from around Blackfoot down
the interstate corridor into the Magic Valley after daybreak
tomorrow and into the early evening before things will likely
change over to snow. This will likely be the best time to get some
accumulations into the lower Snake Plain and Magic Valley zones
but as I said before, each model has a different opinion as to
when this will happen and just how warm we`ll actually get during
the daytime hours. All that being said, we`ve reached the point
where now we just waiting to now-cast the event once it begins as
opposed to having a high confidence forecast. Confidence is
highest for elevations above 5500-6000 ft where p-type will
certainly be all snow and accumulations across the central
mountains, eastern highlands and into the higher terrain of the
south hills will certainly cause impacts throughout the day
tomorrow and into the first half of the day on Friday.
.LONG TERM...Friday through Wednesday. Remnants of upper system
lingers into Friday with light snow showers mainly southeast half
of forecast area. That precipitation should diminish through the
day. Drying and slow/weak warming trend onset for the weekend as
ridge of high pressure builds across the western states, shifting
east on Monday. Ensemble clusters are very close on timing of the
upper trough moving in beginning late Monday/Tuesday. There is
however quite a bit of spread on the depth of the system. Overall
precipitation at this point does not look overly impactful, but a
trend toward a colder system could lead to higher snow totals for
lower elevations. The unsettled conditions look to continue into
the latter half of the week. DMH
&&
.AVIATION...
Early morning fog has finally broken up over the Teton Valley and
KDIJ. VFR conditions across the region this afternoon will begin
to transition toward MVFR this evening as deeper moisture and
precipitation move north into East Idaho, currently located over
northern Nevada per regional radar imagery. KBYI the first to
transition CIGS lower, with -SHRA beginning this evening. The
remaining sites transition late evening or overnight. Moving
through the night, with cooler overnight temperatures, expect a
mix with or change to -RASN or even -SN. This would signal the
transition to IFR or even LIFR with lower VIS as well. DMH
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 8 PM this evening to 11 AM MST
Friday for IDZ051>055-061>065.
Winter Storm Warning until 11 AM MST Friday for IDZ056>060.
Winter Weather Advisory from 11 PM this evening to 5 AM MST
Friday for IDZ066>069-073>075.
&&
$$
Area Forecast Discussion
National Weather Service Raleigh NC
848 PM EST Wed Mar 5 2025
.SYNOPSIS...
A cold front will push eastward through the area this evening. Cool
high pressure will build across the Southeast Thursday, then a weak
warm front lifts northward through the area Friday. A surface low
will track west to east over North Carolina Friday night and
Saturday, helping to push this front back southward through the area
as a backdoor cold front Saturday evening. As this front settles to
our south, another low tracking along the front will bring a chance
for unsettled weather Saturday night through Sunday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 846 PM Wednesday...
The main moisture axis and associated convection from earlier has
moved offshore this evening. However, residual mid-level vorticity
perturbations continue to move east generating isolated showers
across the mountains and foothills. Drying and subsidence behind the
exiting vorticity features should largely promote dry conditions for
central NC tonight. However, a few stray showers will be possible
the next hour or so primarily in the Triad. Additionally, a strong
vort max currently over eastern AL/western GA will skirt to just our
south, but may generate some light rain across the far eastern
Coastal Plain near sunrise tomorrow (recent runs of the HRRR
simulate this potential).
Otherwise, the sfc cold front currently entering the mountains
should sweep through overnight. Modest CAA will dip temperatures
down into the mid 30s to lower 40s (NW to SE). Residual pre-frontal
gusts of 15 to 25 mph will persist (strongest in the Triad) through
early tonight. Similar gustiness will persist as flow turns nwly
post-frontal passage through sunrise Thursday.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
As of 340 PM Wednesday...
* Cooler and blustery once again...
We may see some morning clouds in E NC into the Coastal Plain Thu
morning as a prominent vorticity lobe swings through the base of the
deep and negatively tilted mid level trough, but overall, as this
trough shifts ENE away from the CWA, we`ll see fair to mostly sunny
skies. CAA and a fairly tight MSLP gradient will result in sustained
12-20 mph winds with gusts up to 25-35 mph. This is largely below
wind advisory criteria, but it`ll be close. As drier air pours in,
our RH will bottom out at 25-35%, which, along with the winds, might
bring some fire weather concerns if not for today`s rainfall, which
has helped by moistening some of the smaller fuels. Thicknesses will
be 20-30 m below normal, supporting highs in the 50s when factoring
in considerable insolation. Much of Thu night will be clear, but
expect increasing high and mid clouds late in the W ahead of the
next low over the Plains. Expect lows mostly in the mid 30s. -GIH
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
As of 155 PM Wednesday...
No significant hazards are expected during this time frame, but
we`ll see couple bouts of clouds through this weekend, and there is
a low-confidence chance of rain Sat night into Sun.
Fri-Sat: Expect dry weather Fri, but with increasing and thickening
clouds. Surface high pressure over GA/FL early Fri will push E off
the Southeast coast, ramping up our SW low level flow as a diffuse
warm frontal zone lifts NE into the area and stalls somewhere across
VA or NC. Our mid level flow will remain rather flat and unperturbed
Fri, as a flat/broad polar low sits over Ont/Que and a southern
stream trough sits over the far Desert Southwest, with energy
stretching NE into the central Plains, corresponding to a surface
low. As this vorticity shears eastward through the Ohio Valley and
Mid Atlantic through Sat, the surface low will quickly weaken as it
tracks eastward along the frontal zone, although as this energy
enters the broad polar trough, it will kick the front back southward
through NC as a cold front. Some model guidance is indicating spotty
showers ahead of and with this frontal passage Fri night into Sat,
mainly N, there doesn`t appear to be enough deep saturation, esp in
the low levels, for any impactful precip, plus forcing for ascent is
weak at best. Will keep it dry through Sat, although a few sprinkles
can`t be ruled out across the NE. Expect seasonable highs Fri in the
upper 50s to lower 60s, then Sat looks pretty mild as we get into
the warm sector for at least part of the day, with highs in the
upper 60s to upper 70s.
Sat night-Mon: This looks to be our best and only chance for decent
rain during this period, although confidence is not high. The Desert
Southwest low, located over NM Sat morning, will open a bit and
shift E as a positively tilted shortwave trough through the Gulf and
Southeast states and Carolinas through Mon, with a corresponding
surface low tracking E along the frontal zone. The latest models and
ensemble output generally agree on a rain shield accompanying this
low, however they remain varied as to the track, speed, and
amplitude of the shortwave trough. There is enough general
agreement, however, that there will be sufficient sheared vorticity
spreading through the Carolinas to support at least a 30-40% chance
of rain, mainly across our SSE half, Sat evening through Sun, with a
lower chance across the NW. The expected cloudiness on the cool side
of the front should hold temps down in the 50s areawide Sun, and if
our rain chances trend higher as we get closer in, these may even be
too warm. Expect decreasing clouds from the W Sun night/Mon as the
low pushes offshore, allowing mild high pressure to begin building
in from the SW. Highs Mon should be in the 60s to near 70.
Mon night-Wed: Quiet and warm weather expected under surface high
pressure, with flat ridging over the Gulf states and Southeast. The
next shortwave trough is expected to track into the S Plains Wed,
which should result in increasing clouds late Wed, but expect it to
stay dry here through Wed. -GIH
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
As of 703 PM Wednesday...
Gusty winds will remain an issue this evening, with SW winds
becoming west at 15-25kt, a few gusts to 30kt lingering through
around 06z. Otherwise, VFR conditions expected.
Looking beyond 12z Thu, gusty WNW winds will persist through Thu
afternoon. Otherwise, VFR conditions will largely dominate through
Mon. We`ll have increasing and thickening high and mid clouds late
Thu night through much of Fri, mainly N, as a front approaches from
the N with a low pressure center tracking along the front. This
front will drop through late Sat, bringing another round of clouds
and light rain chances, mainly SE, Sat evening into early Sun as
another low pressure center tracks along the front to our south, but
still expect VFR conditions to hold. Fair skies and high chances for
VFR conditions return Mon under high pressure. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Hartfield
NEAR TERM...Luchetti/Heaphy
SHORT TERM...Hartfield
LONG TERM...Hartfield
AVIATION...Badgett/Hartfield