Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/02/25
Area Forecast Discussion
National Weather Service La Crosse WI
1020 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Snow moves in late this afternoon and evening near and north
of I-90 with periods of heavy snow possible at times. The
snow will transition to rain throughout the evening south of
I-94 and overnight north of I-94 where a mix of sleet/freezing
rain will occur early Wednesday morning before switching to
rain.
- Snowfall accumulations of 2 to 4 inches are expected north of
I-94 by daybreak Wednesday. Accumulations of up to 1 inch will
be possible near and north of I-90 where heavier snowfall
rates occur this evening.
- Potential for strong to severe storms Wednesday morning and
early afternoon, mainly in southwest WI and northeast IA. The
main hazards with any severe storms will be large hail and
damaging wind gusts.
- Seasonable to slightly cooler than normal temperatures for Thursday
and onward with some precipitation chances (20-40%) for the
weekend.
&&
.DISCUSSION...
Issued at 141 PM CDT Tue Apr 1 2025
Rest of Today - Tonight: Snow, Wintry Mix Changing to Rain
As we progress later into this afternoon and this evening, a wing of
mid-level theta-e advection and associated 500-700mb frontogenesis
pushes through the area. As this occurs, sounding profiles in the
HREF sounding ensemble suggesting fairly uniform residence below the
freezing layer to the surface with cloud ice present near and north
of I-90. As a result, expecting precipitation with this band to
begin as snow, maybe mixed with rain near the I-90 corridor but then
switch over to rain as the low-levels warm up ahead of an incoming
warm front. Important to note that this transition time and the rate
at which snow falls will be crucial for any accumulations at all
south of I-94. The recent HREF has some probabilities for inch per
hour snowfall rates (10-40%) during the evening between I-94 and I-
90 for a brief period before the transition to rain occurs. As a
result, a few of the CAMs have some snowfall accumulations with
modest probabilities (40-70%) for an inch or greater of accumulation
in this area assuming a 10:1 snow-to-liquid ratio which likely is
not wet enough. So the general idea south of I-94 and to the I-90
corridor is if rates can manage to be heavy enough, some minor
accumulations of up to an inch may occur before transitioning to
rain.
Further north across Clark and Taylor counties, this mid-level
frontogenetic band shifts northward into the evening hours with more
favorable thermodynamics for a purely snow solution to persist for
several hours. As a result, the 01.12z HREF has high confidence for
accumulations of 2 inches or greater (60-90% chance) in Taylor and
Clark counties. As we head into the overnight and early Wednesday
morning, a warm front will move towards the area allowing for low-
level warming aloft. As this occurs, surface temperatures at
freezing will enable a period of sleet and freezing rain as
suggested in several of the short-range models. This is reflected in
the 01.12z HREF as well which has medium probabilities (30-60%) for
measurable freezing rain across both Clark and Taylor counties.
Eventually later into the morning, the low-level warm advection
regime wins out and a complete transition to rain occurs in north-
central WI.
Tomorrow Morning - Afternoon: Widespread Rain, Strong to Severe
Storms Possible For Southwest WI/Northeast IA
As previously mentioned, the early morning hours on Wednesday
feature a strong warm advection signal pushing northward through the
area. As this occurs, widespread rainfall will quickly move through
the area during the morning hours with some storms possible across
portions of southeast MN and northeast IA. Given the warm advection
taking place, a fairly stout capping inversion can be noted in this
area at 700-800mb which will keep any convection elevated. So while
low-level hodograph curvature looks fairly spooky during the morning
hours, this would not be realized as it is maintained in a stable
layer. Regardless, given the over cyclogenesis and synoptic setup,
cannot completely rule out some gravity wave enhancement which
may lead to localized damaging wind gusts out ahead of the warm
front Wednesday morning. Some isolated hail of up to quarter
sized may be possible as well with mid-level lapse rates of 7-8
C/km and freezing levels of 7-9kft. However, very limited MUCAPE
would mitigate this potential with the 90th percentile HREF
only having 50-200 J/kg at Platteville, WI during the morning.
So general thinking with the morning convection is very low
confidence for any severe potential with the 01.12z HRRR neural
network probabilities agreeing with this with minimal severe
weather probabilities (5-15% with a 120km neighborhood radius).
The question as we head towards the afternoon will be exactly if and
how much recovery we see when the warm advective convection attempts
to exit the area. Currently, the 01.15z RAP displays a narrow window
where some 850mb moisture transport could advect in some increased
instability of 1000-1500 J/kg MUCAPE that based on afternoon
RAP/HRRR soundings could be surface based as the cap gets
removed. Low-level shear profiles change profoundly during this
period as well with the surface low progressing northeast of
the area and shifting the wind direction at the surface to
southwesterly/westerly. Consequently, a shift from sharp low-
level curvature to straight line hodographs are noted. As a
result, thinking the potential for a weak tornado in Grant
County is in a very narrow window, possibly less than an hour
even and still conditional on if we managed to get the
instability in. With the stronger synoptic winds aloft and very
heavily sheared profiles, both hail and damaging winds would be
in play where SPC has a slight risk (threat level 2 of 5) in
portions of southwestern WI and northeast IA if healthier
convection does materialize. However, by middle to late
afternoon the cold front will push through the area and
effectively wipe out any chances for severe potential, again
highlighting that this window is very brief. Overall, HRRR
neural network guidance is slightly more confident in this
period with 20 to 40 percent probabilities for all severe
weather hazards, mostly driven by damaging wind gusts.
Thursday - Sunday: Quieter Conditions and Remaining Cooler
As we look past this spring system, upper-level southwesterly flow
takes place over the region with a broad synoptic ridge to our east
and a trough situated to the west. Overall, minimal waves in the
flow are noted into the weekend. As a result, not expecting much for
precipitation on Thursday and Friday, however without a more
substantial ridge setting up shop in the area may be difficult to
clear our skies out completely. Regardless, as we head into the
weekend, a northern stream trough will begin to phase with the
previously mentioned western trough which will cool down our
temperatures as it ushers in a slightly cooler airmass for Sunday
and Monday with highs in the 40s for much of the area. Cannot rule
out some precipitation chances with the grand ensemble
(GEFS/Canadian/EC ens) having medium probabilities (30-50% south of
I-90) for measurable precipitation if the two synoptic troughs phase
in such a way that allows the deformation zone of a developing
surface low to sneak into southern portions of the area.
&&
.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1020 PM CDT Tue Apr 1 2025
CIGS: VFR cigs expected to push across the TAF sites for a few hours
of the overnight before MVFR/IFR return with areas of (mainly) rain.
These lower cigs look to hold into Wednesday afternoon. Some
improvement, potential scattering to VFR still trended for KLSE.
Same trends still want to keep KRST at least MVFR. Those low cigs do
return to KLSE later Wed evening and will hold through the nighttime
hours.
WX/vsby: Short break in the widespread pcpn before the CAMS slide
more rain across the TAF sites...roughly in the 09-14z time frame.
Another break is favored for the rest of the morning with the CAMS
then suggesting narrow convection along a cold front for the
early/mid afternoon hours. Consistent signal and will cover this
with a PROB30.
WINDS; east southeast into Wed afternoon, swinging west/southwest as
a sfc low and cold front move northeast. Going to stay windy with
gusts in the mid 20s to low 30 kts.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Winter Weather Advisory until 10 AM CDT Wednesday for WIZ017-
029.
MN...None.
IA...None.
&&
$$
DISCUSSION...Naylor
AVIATION.....Rieck
Area Forecast Discussion...Updated
National Weather Service Billings MT
913 PM MDT Tue Apr 1 2025
.KEY MESSAGES...
- Periods of mountain and foothill snow through Wednesday. Several
inches of snow accumulation can be expected (8 to 16" mountains;
2 to 5" foothills), with light snow accumulations over the lower
elevations. Main impacts will be slushy/slick roads and reduced
visibility in snow, mainly over the mountains and foothills.
- Clipper system brings next shot of lower elevation snow and
colder temps Thursday night and Friday.
- High confidence of building high pressure this weekend; expect
warmer and dry conditions into next week.
&&
.UPDATE...
Updated the forecast to adjust PoPs and cloud cover to radar
imagery and latest model data. There is a lull in the
precipitation from about Park County, MT east/southeastward to
Sheridan County, WY this evening. This break in the precipitation
will end overnight as bands of rain and snow move southward into
the area. Did lower some precipitation amounts for this evening
but the rest of the precipitation forecast looks on track.
Also, added some fog to the forecast, first over southeast MT,
especially near Treasure, Big Horn and Rosebud Counties (Lame Deer
Divide MT DOT web cam shows fog) this evening, then to much of the
area after midnight MDT into Wednesday morning. HRRR suggests the
more persistent fog should occur near eastern Big Horn County
tonight. Elsewhere, fog should be patchy. Any fog should diminish
from north to south during the day Wednesday. RMS
&&
.DISCUSSION...
Through Thursday afternoon...
A large upper trough situated over the western US continues to
bring southwest flow and upper diffluence over the region. Within
this large upper trough, an embedded shortwave trough is moving
northeast through Wyoming this afternoon. As this shortwave moves
into the Dakotas this evening and night, it is expected to
strengthen into an upper level low. While these upper level
features are the main driving force for the forecast, the broad
nature of the large upper trough continues to introduce
uncertainty to the precipitation forecast through Wednesday.
With that said, a broad north-south band of precipitation is
currently situated over south- eastern Montana, east of Billings,
this afternoon. By this evening into tonight, precipitation is
expected to build back in over south-central Montana as the upper
level low develops in the Dakotas. This will also bring wrap
around precipitation to areas in far eastern Montana. As we go
through tonight into Wednesday, the area of precipitation in
south-central Montana is expected to sink south into the mountains
and foothills south of Billings before tapering off mid-day
Wednesday. The wrap around precipitation in far eastern Montana
also looks to taper off through mid-day Wednesday. After this,
unstable northwest flow looks to keep isolated to scattered
rain/snow showers in the forecast for south-central Montana
through Wednesday evening. As far as precipitation type goes for
this event, all snow is expected in the mountains. Over the lower
elevations, a rain/snow mix can be expected during the day, with
mostly snow expected at night.
With this event, the overall precipitation totals have remained
similar to last nights forecast. Currently, precipitation amounts
of 0.25 to 0.75 inches are forecast from Harlowton to Billings to
Sheridan, with much less precipitation expected around Miles
City, Baker, and Ekalaka. While the western foothills will
continue to be downsloped most of today, around 0.15 to 0.50
inches are still forecast in this region. With regards to snow, a
few inches of snow are possible for foothill locations, with
generally an inch or less for the lower elevations. Greatest
accumulations will be on grassy surfaces and near the mountains.
Several inches are possible in the mountains with up to 16 inches
total in the Beartooth- Absaroka and Crazy mountains, and up to 12
inches total in the Bighorn and Pryor mountains. With that said,
the winter weather products across our area remain in good shape.
Look for temperatures to remain in the 40s Wednesday and 40s to
lower 50s Thursday. After a break in the precipitation Wednesday
night through Thursday morning, another weather system will bring
the chance of precipitation back to the region Thursday evening.
See the long term discussion for more information. Arends
Thursday night through Tuesday...
Western U.S. troughiness continues over the area Thursday night
and Friday, but will become more organized during the period. The
N portion of the trough will affect the forecast area as it moves
E. Decent 700 mb frontogenesis drops SE through the area Thursday
night through Friday morning. Surface cold front moves S through
the area Thursday night, or Thu. night through Friday morning,
with ECMWF having the fastest movement. QPF amounts and placement
differed between the models, but all of them indicated upslope
flow. NBM PoPs were a reasonable solution based on the above.
Expect moderate to high PoPs over the area Thu. night with a
rain/snow mix changing to all snow. PoPs were in the 20% to 60%
range Friday morning, with the highest PoPs over Sheridan County.
The probabilities of 2 or more inches of snowfall were 20-30% over
KBIL and KSHR, with 40-90% over the upslope areas. Chances for at
least 6 inches over the NE Bighorns were 10-30%. Precipitation
chances decrease quickly Fri. afternoon.
With a strong pressure gradient and the frontal passage Thu.
night, have increased wind speeds/gusts by 30% toward the NBM 90th
percentile. Cold advection over the E through the day on Friday
will create breezy conditions in this area. Lows Thu. night will
be in the 20s with highs on Friday below normal in the mid 30s to
lower 40s. There was a 30-40% chance of highs reaching only 32
degrees W of KBIL and over KSHR.
Region will be on the E side of an upper ridge on Saturday under
northerly flow. This pattern continues on Sunday. Expect dry
weather and a warming trend with temps in the 50s to lower 60s on
Sunday. Upper ridge will be over the forecast area on Monday, but
Clusters differed in the depiction of the ridge. Temps will
continue to moderate with dry weather over the area. Clusters had
either SW flow aloft or upper ridging on Tuesday. NBM gave some
low PoPs over and near the mountains in the afternoon.
Keep an eye on the forecast for any changes to the system early in
the period and for changes late in the period with the
uncertainty in the pattern. Arthur
&&
.AVIATION...
Band of rain showers with some snow showers will affect areas from
KBIL to KSHR E through this evening. There will be scattered
rain/snow showers W of KBIL. Scattered to widespread rain and snow
showers continue overnight through Wednesday 18Z, with the best
chances from KBIL S. Expect MVFR to IFR conditions in the
precipitation. Surface wind gusts will be in the 30s kts W of KBIL
through this afternoon. Expect widespread mountain obscurations
through the period. Arthur
&&
.PRELIMINARY POINT TEMP/POPS...
Wed Thu Fri Sat Sun Mon Tue
-----------------------------------------------------------
BIL 035/047 029/050 028/041 023/055 032/061 035/068 040/068
78/W 24/W 73/S 10/U 00/U 00/U 01/B
LVM 030/044 027/046 026/039 021/051 031/058 035/063 038/061
67/W 24/J 73/S 10/U 00/U 00/U 12/R
HDN 032/047 027/051 027/042 020/053 028/061 031/068 036/069
88/W 24/W 73/S 10/U 00/U 00/U 01/U
MLS 033/045 027/050 026/039 021/051 029/056 030/066 037/069
33/W 13/W 51/B 00/U 00/U 00/U 00/U
4BQ 032/042 027/050 028/038 020/049 029/054 029/064 036/067
66/W 12/W 63/S 10/U 00/U 00/U 01/U
BHK 028/040 024/048 023/038 017/047 024/050 024/060 033/065
55/J 12/W 62/S 10/U 00/U 00/U 00/U
SHR 026/041 022/047 023/036 014/048 025/055 028/064 033/063
58/W 24/W 66/S 21/U 00/B 00/U 01/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory in effect until 6 PM MDT Wednesday
FOR ZONES 40-56-63>66-141-171-172-228.
Winter Storm Warning in effect until 6 PM MDT Wednesday FOR
ZONES 67-68.
Winter Weather Advisory in effect until 3 PM MDT Wednesday
FOR ZONE 138.
WY...Winter Weather Advisory in effect until 6 PM MDT Wednesday
FOR ZONE 198.
Winter Weather Advisory in effect until 3 PM MDT Wednesday
FOR ZONE 199.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service State College PA
1114 PM EDT Tue Apr 1 2025
.SYNOPSIS...
Low pressure will track west of Pennsylvania through the Great
Lakes Wednesday night into Thursday. The trailing cold front
will push through Central Pennsylvania late Thursday, then stall
out out of just south of the region late this week. A wave on
the stalled front is likely to lift up the Ohio Valley and
across Pennsylvania next weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
High pressure nosing south from S Ontario/Quebec will provide
Central PA with fair and chilly weather tonight, along with
light winds. Evening satellite imagery shows high clouds
associated with an approaching warm front over the Midwest
streaming across Northern PA. Latest HREF cloud progs indicate
any cirrus will be fairly thin for much of the night, then
thicken up around daybreak over the western counties.
Mostly clear skies for much of the night, combined with light
wind and dry air, should support efficient radiational cooling
and min temps a bit below NBM guidance, especially over the
eastern counties. Expect daybreak readings to range from the mid
20s in the valleys of North-Central PA, to the mid 30s in the
more urbanized spots of the Lower Susq Valley.
Isentropic lift at the nose of a strong southerly low level jet
lifting into the Grt Lks will likely produce a round of showers
across much of Central PA Wed afternoon/early evening. The
strongest forcing and highest POPs of around 90 pct are across
the NW Mtns, while the Lower Susq Valley stands the least chance
of measurable rain. Latest CAMS indicate the most likely
timeframe for showers will range from mid afternoon over the NW
Mtns, to early evening over the eastern edge of the forecast
area. Mostly cloudy skies and a southeast flow off of the chilly
Atlantic Ocean should result in max temps Wed a bit below
normal for early April.
&&
.SHORT TERM /WEDNESDAY NIGHT/...
The showers should lift north of the PA/NY border by late Wed
evening with the retreating 8H baroclinic zone. Focus then
shifts to an upstream cold front and associated line of
convection, which should push into at least the northwest part
of the forecast area by dawn Thursday. Current progs indicate
minimal surface based instability, but 70kt winds at 850mb
supports a MRGL risk of damaging wind gusts toward dawn over
the Allegheny Plateau.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Showery and mild weather is expected Thursday, as the area
briefly breaks into the warm sector ahead of an approaching cold
front. 18Z EPS plumes suggest the best chance of PM severe
weather will be across the Lower Susq Valley, where moderate
instability (CAPE near 1000J/kg) is progged in conjunction with
deep layer shear of around 40kts.
The cold front is then progged to stall out just south of PA
Thursday night. A wave on this boundary looks increasingly
likely to result in a period of rain Thursday night into early
Friday, especially across Northern PA.
Latest EPS/GEFS suggests a brief period of cool and drier
weather is likely Friday/Friday night associated with a surface
high passing north of PA. However, medium range guidance
indicates another wave of low pressure riding along the stalled
front will result in a rainy weekend. Latest ensemble mean qpf
between Thu night and Sun PM ranges from 1 to 2.5 inches over
Central PA, with the highest totals focused over the NW Mtns
and the least across the Lower Susq Valley. The southeastern
part of central PA has been under moderate to severe drought
conditions for quite some time, so any rain over that part of
the state would be beneficial.
There is broad consensus among medium range guidance that upper
troughing builds over the region early next week, accompanied by
below normal temperatures and scattered rain/snow showers over
the Allegheny Plateau. Below average temps are favored for much
of next week, which could raise some frost/freeze concerns as
the spring growing season gets underway.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
All model guidance continues to indicate VFR conditions with
clear skies for a majority of the overnight period (through 10Z
Wednesday) with the bulk of model guidance leading to high
(~80-90%) confidence in VFR conditions remaining through 18Z
Wednesday. Recent model guidance brings a line of showers
towards BFD in the 18-20Z timeframe, overspreading eastward
through 00Z Thursday, with some potential for TSRA across W PA.
At this time, mentions of TSRA are out of the 00Z TAF package as
elevated instability is not the most impressive; however cannot
rule out some thunder across BFD/JST/AOO. Ceilings are expected
(~80-90%) to prevail MVFR at BFD/JST with some signals in RAP
model guidance for IFR ceilings at onset at BFD. IFR conditions
at BFD seem to be a less likely scenario (~30% probability),
thus have kept any mentions with a PROB30 group. Further SE
(LNS/MDT), lower confidence on SHRA impacting the airfields
based on drier low-levels, thus have kept mentions out of the
00Z TAF package at this time.
Outlook...
Thu...MVFR poss in widespread rain showers. TSRA poss, mainly S.
CFROPA aftn/eve.
Fri...MVFR cigs and visby expected, mainly S.
Sat...Widespread showers; impacts likely.
Sun...Widespread showers; impacts likely.
&&
.CLIMATE...
Closing out very mild March 2025. Below are the rankings and
departures from the historical average through 3/30:
Site Avg. March temp Rank
Harrisburg 46.5F (+4.9F) 12th warmest
Williamsport 44.8F (+6.2F) 9th warmest
Altoona 44.4F (+5.9F) 7th warmest
Bradford 40.2F (+7.3F) T3rd warmest
State College COOP site STCP1 recorded the 10th warmest March on
record with an average monthly temperature of 43.3F.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Fitzgerald
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald
LONG TERM...Fitzgerald
AVIATION...NPB
CLIMATE...Steinbugl
Area Forecast Discussion
National Weather Service Dodge City KS
955 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Strong surface low will support dangerous fire weather
conditions west of a dryline this afternoon, and severe
thunderstorm potential to its east.
- Widespread, multi-day precipitation event coming into focus
Thursday through Saturday.
- Below-normal temperatures also likely Thursday through
Saturday.
&&
.UPDATE...
Issued at 946 PM CDT Tue Apr 1 2025
-- Mesoscale Discussion
Isolated supercells are still possible along and ahead of a
dryline through 11 pm. These storms could contain large hail.
However, a cold front could result in a line of storms before
midnight across Pratt, Stafford, Barber and Comanche counties.
These storms may contain winds up to 60 mph and hail as large as
quarter size. The chances for severe storms will shift east of
Pratt and Barber counties by 1 am.
&&
.DISCUSSION...
Issued at 200 PM CDT Tue Apr 1 2025
19Z upper air RAP analysis and water vapor satellite imagery
reveal southwesterly flow sits atop the central and southern
plains ahead of weak, broad troughing over the western CONUS
with an embedded shortwave trough now ejecting onto the central
plains. As these features approach, an already ~990-mb cyclone
centered over west-central KS will deepen further and shift
across KS this afternoon and evening. As this happens, a dryline
will sharpen and translate eastward across our area while a cold
front approaches from the north. Deep boundary layer mixing west
of the dryline will support strong southwesterly winds, blowing
dust, and dangerous fire weather conditions, especially along
and west of US-283. East of the dryline, strong southerly winds
will draw moisture poleward, fortifying thermodynamic profiles
amidst robust kinematics, which will set the stage for the
potential for severe thunderstorms this evening. Current
thinking is thunderstorms will initiate near the cold
front/dryline triple point around 23-01Z across our
east/northeast zones, and rapidly move northeast into central
KS. While residence time in our area is likely to be limited,
any storm that develops will be capable of producing hail up to
the size of tennis balls and winds in excess of 60 mph. The
tornado threat will be near zero as storms will struggle to
mature fully before exiting our area, but cannot be entirely
ruled out. Overnight, the aforementioned cold front will pass
through our area, and northerly winds will advect cooler air
equatorward with Wednesday morning lows ranging from the low/mid
30s northwest to the mid/upper 40s southeast.
Daytime Wednesday, short range ensembles are in agreement
shortwave ridging will pass overhead between a pair of shortwave
troughs embedded within the broader, longwave trough that
encompasses the western CONUS. While cooler post-frontal air
will be in place across southwest KS, downsloping west-northwest
winds will promote afternoon highs in the mid/upper 60s for
most, with the Red Hills region reaching the low 70s.
Thursday through the end of the period, medium range ensembles
suggest the broad, longwave trough over the western CONUS will
finally pick up speed and eject onto the High Plains by the
weekend. As this synoptic feature closes in, precipitation
chances will gradually increase, and confidence is growing in a
multi-day, multi-round precipitation event continuing from
Thursday afternoon through Saturday night. At the moment, the
Friday afternoon through Saturday evening period appears to be
the peak, with NBM pops well into the likely (55-74%) and
definite (75-100%) categories. Precipitation will fall as mostly
rain, however, there is a brief period Saturday evening as the
precipitation is tapering off in a switch to snow, especially
across our northwest zones, as cold air spills into southwest
KS. Once all is said and done, the ECMWF EPS and GEFS ensembles
indicate widespread 0.5-1" of precipitation is expected, which
mirrors 72-hr NBM probability of QPF > 0.75" in the 50-80%
range for all zones.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 600 PM CDT Tue Apr 1 2025
Southwest winds of 15-25 kt will continue this evening. A sfc low
pressure center will eventually form over the state through tonight
and into the overnight hours. We will eventually see W to NW winds
by tomorrow in the 15-25 kt range as well. As far as storms go, the
most likely terminal being impacted late this evening still looks
to be KHYS. Will have VCTS/CB groups for this terminal tonight.
KDDC/KGCK might see VCSH, but there is a general trend of keeping
the storms east of this terminal.
&&
.FIRE WEATHER...
Issued at 200 PM CDT Tue Apr 1 2025
Dangerous fire weather conditions are likely this afternoon,
mainly along and west of US-283.
Short range ensembles are in agreement a deep surface low will
translate across KS today, with a sharpening dryline reaching
between US-283 and US-183 by mid-afternoon. Deep boundary layer
mixing to the west of this feature will support strong
southwesterly winds sustained in the 25-35 mph range with gusts
up to 50 mph, and relative humidity dropping into the 10-15%
range. As a result, a Red Flag Warning remains in effect for all
counties along and west of US-283 through 8pm CDT this evening.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Finch
DISCUSSION...Springer
AVIATION...Sugden
FIRE WEATHER...Springer
Area Forecast Discussion
National Weather Service Des Moines IA
643 PM CDT Tue Apr 1 2025
...Updated for the 00z Aviation Discussion...
.KEY MESSAGES...
- Slight Risk for hail and damaging winds tonight across the far
south. Marginal extends into central Iowa.
- Slight risk for hail, wind and a tornado or two Wednesday.
Main window for storms will be between 11am and 4pm in
southeast Iowa.
- Fair weather to follow with light rain chances Friday night
into Saturday.
&&
.DISCUSSION...
Issued at 232 PM CDT Tue Apr 1 2025
Theta-e advection formed some advection wing showers this afternoon
which will continue to focus in the north this afternoon. The main
convective activity will arrive later on tonight, this time slower
than previously forecasted. MUCAPE values nearing 1000 J/kg will
just edge into the state, primarily the southern two counties or so,
and harnessing an EBWD of around 30kts. The surface-based potential
stays in Missouri overnight; this far north, there will be a stable
inversion layer near the surface. This focuses the severe weather
risk primarily to hail, but surface-based threats such as winds and
tornadoes are not far to the south, therefore a slight displacement
to the north brings these into the picture. The dry air entrainment
ahead of the stratiform rain may also allow for at least some
gusty winds over west central Iowa.
The most notable change to the forecast is the evolution of synoptic
features tomorrow, specifically speaking about the stacked surface
and H850 boundary. RAP and HRRR runs build up 60 degree dew points
ahead of this boundary. This is paired with an upper-level jet
crossing over into the warm sector side of said boundary, giving a
big boost to shear. Diurnal processes will have mixed the PBL by the
late morning which will allow for surface-based potential to enter
the picture. The shear values are more magnitudally-driven and less
directionally, evidenced by the straight, off-the-chart hodographs.
So the low-level shear values at face-value are deceptive. The
deep-layer shear vectors will point almost parallel to the
front, allowing for a hybrid/linear mode of storms to race
across southeast Iowa. There is some minor discrepancies as to
where the boundary will be in the morning, hence the extended
duration of precipitation chances in southeast Iowa. The quick
destabilization and venting will keep hail as a possibility.
Damaging winds will also be possible, owed mostly to the strong
winds throughout the profile. Tornadoes are possible, especially
if a right-moving storm can harness better streamwiseness in
its updraft. The setup is short-lived in our CWA as storms exit
before the peak heating afternoon hours. Otherwise, for highs
Wednesday, have continued to trend down highs Wednesday due to
pesky cloud cover associated with the deformation zone from the
parent low to the northwest.
In the long term, the aforementioned front will stall over the Ohio
river valley and block low level moisture from reaching Iowa through
the remainder of the work week, save for some rain chances Friday
night when the pattern finally breaks. We will remain on the cooler,
cloudier side of the system to the south. This will keep
temperatures in the 50s. An upper-level ridge will build over the
western CONUS next week and will eventually bring with it more mild
temperatures once it makes its way east.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 643 PM CDT Tue Apr 1 2025
Mainly VFR stratus across the area now with spotty sprinkles to
light rain ongoing. A few pockets of MVFR to IFR status exist,
mainly towards northern Iowa with impacts at KMCW. This will
continue through the evening with a line of storms moving into
the area around 05-06z and pushing east through the early
morning hours. A few of these storms may be severe. These will
come to an end towards 12z, however additional rain is possible
later into the morning with wrap around precipitation on the
back of the system. Confidence in timing and placement of that
is low and will be addressed in future updates. Wind remains
breezy through the TAF period, shifting to out of the southwest
by midday Wednesday.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Jimenez
AVIATION...Hagenhoff
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
642 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Severe storms are expected tonight into tomorrow morning.
Damaging winds, large hail, and heavy rainfall are the most likely
hazards. A low tornado risk also exists.
- Gusty winds around 30-40 mph are expected to continue through
Wednesday afternoon. Isolated gusts above 45 mph are possible.
- The pattern remains active with daily chances for rain through
Sunday.
&&
.DISCUSSION...
Issued at 319 PM CDT Tue Apr 1 2025
SPC Mesoscale Analysis depicts a surface low to the west over the
KS/CO border. With a surface high to our NW, a strengthened pressure
gradient combined with 30-40 kts at the top of the mixed layer has
lead to breezy (30-40 kt gusts) conditions across the area. Strong
theta-e advection from southerly winds will assist in highs reaching
the mid 50s to upper 60s today. Some light showers and storms have
developed as the warm front, associated with the surface low to our
west, moves farther north. These storms are expected to remain
benign as there is limited instability to work with.
The dry line, as of 20Z, is currently situated over eastern KS and
is expected to continue to mix east through the day today. The cold
front, associated with the aforementioned surface low to our west,
is anticipated to overrun the dry line. This, will act as a catalyst
for severe thunderstorms later tonight into Wednesday morning. A few
discrete cells are expected to develop in central and eastern KS
along the dry line later tonight around 8-10 PM. These cells are
anticipated to track to the northeast entering central MO around
midnight. An 850 MB LLJ sets up making the thermodynamic profile
more favorable for severe weather. Bulk shear values around 60-70
kts and MUCAPE values around 500-1000 J/kg make damaging winds and
large hail a possibility. There is also a risk for a tornado or two
with plenty of 0-1 KM SRH available. These cells are expected to
move through the area and exit the CWA to the NW around 2-4 AM
tomorrow morning.
The second round of convection is expected to be more significant
than the first and will develop as the cold front overruns the dry
line (as previously stated) in central KS around midnight. The most
recent HRRR model runs have been consistent in the development of a
line of storms in central KS with a northeast to southwest
orientation. This line of storms is expected to traverse to the east
reaching the KS/MO border by around 4-6 AM Wednesday morning. The
850 MB LLJ continues to intensify after midnight creating a much
more favorable environment for severe weather. MUCAPE values exceed
2000 J/kg, DCAPE values ranging from 700-900 J/kg and bulk shear
values exceed 70 kts. This kind of thermodynamic profile makes all
hazards a possibility. Damaging winds and large hail will be the
main threats if that CAPE is realized. A few spinups are possible
along the line of storms with SRH values exceeding 200 m2/s2. PWATs
range from 1.2-1.45 which is actually above the max percentile for
climatology. If storms begin to train or storm motions are slower
than anticipated, minimal flooding could become a concern. At this
time, the higher flood threat seems to be south of the CWA and
storms are expected to be progressive enough to minimalize flooding
concerns. This line of storms is expected to exit the CWA by around
8-10 AM tomorrow morning. This will keep the severe threat looming
until the early morning tomorrow and may impact morning commutes.
Wednesday morning into the afternoon is expected to be very breezy
with winds gusting up to 30-40 mph behind the front. A few isolated
gusts to 45 mph are possible during this time. Wind advisory
criteria is possible however, decided to hold off for now as 45 mph
winds gusts seem more sporadic in nature. Winds on the backside of
the front come out of the west resulting in in highs for tomorrow
staying warm ranging in the low 60s to low 70s.
The pattern remains active for the second half of next week as an
upper level trough sets up in the Four Corners regions and ejects
shortwaves towards the area. This will result in daily chances for
rain from Thursday through Saturday. Late Saturday, an upper level
ridge pushes the trough back into the flow as it delivers us one
final chance for rain late Saturday into Sunday. Mid to upper level
ridging moves over the area suggesting drier conditions for the
first half of next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 642 PM CDT Tue Apr 1 2025
Gusty conditions continue through the period. Flow is attempting
to decouple; however, intermittent gusts will likely reach the
surface. TSRA forms across central and eastern KS moving into
the area overnight. Some convection is expected around 04-06Z
ahead of the main line of storms which arrives around 10Z. Sky
coverage and CIGs improve behind the convection; however,
diurnal mixing once again creates gusty winds through the
remainder of the TAF period.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...None.
KS...None.
&&
$$
DISCUSSION...Collier
AVIATION...Pesel
Area Forecast Discussion
National Weather Service Hastings NE
612 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Thunderstorms still possible (50-60%) late this afternoon into
the evening hours. Marginally severe storms primarily
possible east of Hwy 281.
- Cooler after today. Temperatures rebounding for the start of
the next work-week.
- Various other precipitation chances Thursday through Saturday
as number of disturbances move across the Central Plains.
&&
.DISCUSSION...
Issued at 220 PM CDT Tue Apr 1 2025
The primary concern with this forecast is the thunderstorm
potential this afternoon and evening. As of 2pm, there is
clearing across much of area from Cambridge, NE to Franklin, NE
and south across much of north central Kansas. Temperatures are
in the 60s and some are pushing 70. The surface low is in far
northeast Kansas near/along the Colorado border.
As this system begins to eject eastward the surface low is
expected to slide eastward. The triple point is expected to
traverse the area and will be a focus for thunderstorm
development during the afternoon and evening hours. This being
said, the amount of instability the will be present for
thunderstorms across south central Nebraska and portions of
north central Kansas is not overly high. 50 degree dewpoints are
just pushing into south central Kansas, and while the strong
winds will do quick work, the amount of moisture present is
lacking. The latest SPC meso analysis indicates MUCAPE at 2pm of
500 J/Kg along the southeastern Kansas/Oklahoma border. The
primary concern for severe thunderstorms look to erupt along the
cold front as it intersects the moisture in central and eastern
Kansas. That being said, as the dryline/cold front move across
northern Kansas and south central Nebraska, most guidance
indicate the potential for thunderstorm development. The
NAM/NAMNest is much more robust with the return moisture than
the HRRR and thus more instability. While the latest 18z run of
the HRRR indicates that there could be thunderstorms develop as
the triple point moves through, I believe most of this activity
will be weaker and marginally severe at best with CAPE between
500-800 J/Kg. Shear is not in question though, with 60-70 kts
bulk shear present. If the moisture return can get get far
enough north, then the best chance for stronger to severe storms
resides along and east of Hwy 281, but again, I repeat from
above, the best potential for the strongest storms resides to
the south west of us.
Beyond the thunderstorm potential, today, we still have a risk
for critical fire danger, this primarily is in north central
Kansas and nearby southern Nebraska counties. The dry air will
punch into the region dropping relative humidity values into the
teens with strong southwesterly winds. This combo will be
present for a few hours later this afternoon, and any fire that
develops could get out of control quickly.
This upper level system will eject to the east/northeast with
the main trough still residing across the intermountain west
until it pushes across the area over the weekend. During that
time, a few small disturbances will move northeast and impact
the area before the main system to our north moves across the
area, kicking the larger trough eastward. The small disturbances
will bring chances for precipitation for later in the week, but
the next best chance will be ahead of the system coming through
on Saturday.
Temperatures - Today is the warmest day for most, with
temperatures steadily dropping each day through Saturday where
they bottom out before warming quickly into the start of the
work-week.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 605 PM CDT Tue Apr 1 2025
For KGRI/KEAR Airports:
Showers/thunderstorms and sub-VFR conditions are all possible at
both terminal sites through this TAF period...mainly now through
early-mid morning on Wednesday. Ceilings are currently VFR, but
models continue to show the potential for lowering bases with
time, bottoming out after midnight tonight into the early
morning hours. Currently have VFR conditions returning during
the afternoon hours, but that may be optimistic. Winds are
currently easterly at both sites, but direction will turn more
northerly with time this evening, with more WNW winds expected
in the early morning hours, then more westerly through the
daytime hours. There will be a relative lull in speeds through
the evening and at least part of the overnight hours...but gusty
conditions will returning around sunrise, lasting through the
rest of the period.
&&
.FIRE WEATHER...
Issued at 220 PM CDT Tue Apr 1 2025
Critical fire weather conditions are still possible this
afternoon where the dryline pushes through and strong
southwesterly winds are present. This is expected to be present
for a few hours later this afternoon into the early evening
hours before wind change directions to the northwest and
relative humidities increase.
Near-critical fire weather conditions are expected Wednesday
across much of the area primarily along and south of I-80 into
northern Kansas. Breezy westerly winds will be present with relative
humidity values in the 20-30% range.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Red Flag Warning until 8 PM CDT this evening for NEZ082-083.
KS...Red Flag Warning until 8 PM CDT this evening for KSZ005-017.
&&
$$
DISCUSSION...Billings Wright
AVIATION...ADP
FIRE WEATHER...Billings Wright
Area Forecast Discussion
National Weather Service Green Bay WI
1048 PM CDT Tue Apr 1 2025
Updated aviation portion for 06Z TAF issuance
.KEY MESSAGES...
- Another wintry weather system is expected to impact our area
this evening through Wednesday evening. Accumulating snow, light
icing, gusty winds, rain, and some thunderstorms are all
possible with this system.
- Two to five inches of snow, up to a tenth of an inch of ice, and
gusty east to southeast winds to 35 mph could create additional
power outages and make the Wednesday morning commute snow
covered and slippery.
- There is a chance of thunderstorms late Wednesday morning
through Wednesday afternoon. A few strong storms capable of
producing hail and gusty winds are possible, mainly in parts of
central and east-central Wisconsin.
- Rainfall and runoff will likely lead to rises on area rivers,
which may lead to minor flooding at a few locations late this
week.
- The active weather pattern will abate once this system departs
by Thursday morning across northeast Wisconsin.
&&
.DISCUSSION...
Issued at 245 PM CDT Tue Apr 1 2025
Short Term...Tonight and Wednesday
The latest RAP analysis and satellite/radar imagery show surface
high pressure extending south over northeast Ontario and the
central Great Lakes early this afternoon. Quiet and cool
conditions prevail across the region, but clouds are already
moving into northeast Wisconsin ahead of the next storm system.
The surface low with this system is emerging over the lee of the
Rockies with a broad warm advection zone downstream of the low
over the Plains. A band of precip within mid-level frontogenesis
is spreading a light wintry mix into southwest Minnesota and
poised to move into the region tonight. Forecast snow and ice
accumulations, and thunderstorm potential on Wednesday are the
focus of this forecast as this storm system moves across the
region.
Snow And Ice Potential: As southerly return flow increases in
excess of 40 kts, the warm advection/frontogenetical band of
precip will spread northeast across the region this evening.
Arrival timing may have slowed by 1-2 hours, but that`s pretty
minor in the bigger picture. This band of precip is forecast to
gradually weaken as it spreads northeast tonight.
With temperatures warming aloft, precipitation is forecast to
change from all snow to a wintry mix over central and east-central
Wisconsin after midnight and into the HWY 29 corridor by around
12z Wed before changing to rain. Far northeast WI will be the
slowest to change over to rain and may take until midday or early
afternoon Wed.
Confidence in the precipitation amount forecast is the lowest,
which obviously impacts snow/ice amounts. There is a large range
of QPF comparing the CAMS and the medium range models,
particularly on Wednesday morning when strong frontogenesis along
the 850mb warm front is forecast. The latter models (NAM/GFS/RAP)
show precip amounts up to an inch on Wed morning, with some of the
higher amounts moving into far northeast WI where temps remain
near freezing the longest. This scenario is reflected in the HREF
which shows a signal for 1"/hour snowfall rates for a few hour
period over far northeast WI late on Wed morning.
That said, snowfall and ice amounts haven`t changed much in the
latest forecast and will still advertise 2-5 inches of snow,
locally up to 6 inches, and up to a 0.10" of ice. Higher amounts
are possible if the greater QPF amounts develop, particularly over
far northeast WI.
In terms of impacts, concern is highest for snow load from the
snow and ice combined with the southeast winds to 35 mph. Imagine
there are weakened tree branches and powerlines from this past
weekends storm that could fail from the weight of the snow/ice and
force from the wind and lead to additional power outages. The
Wednesday morning commute will likely be slippery over parts of
north- central and far northeast WI due to the snow/ice/blowing
snow.
Made minor changes to start/end times, but no large scale changes
to headlines were necessary.
Thunderstorm Potential: Elevated instability will move in ahead of
the surface low on Wednesday morning and afternoon. While some
thunder will be possible on Wednesday morning, potential for
severe storms is generally low. That may change by mid to late
afternoon as elevated capes around 500-800 could move into parts
of central and east-central WI. Effective shear values of 60-70
kts will be supportive of rotating updrafts which could lead to
isolated storms producing 1" hail. Will continue to have a mention
in the HWO. The main period of concern will be between 2-7 pm on
Wed over east- central WI.
Long Term...Wednesday Night Through Tuesday
The rest of the forecast quiets down as northern Wisconsin
becomes under the influence of a dominant northern stream trough.
This northern stream trough will shift the storm track to the
southeast of the region for late this week and through the
weekend.
Light snow or flurries could linger across north-central WI into
Thursday morning with moisture aloft hanging back over northwest
Wisconsin within the comma head. Lack of deep saturation suggests
little to no accumulations will be possible. West winds of 30-35
mph within cold advection will subside over the course of the day.
But the winds could lead to minor blowing and drifting of the new
snow on north-south orientated roads.
Otherwise, quiet and cool conditions will generally prevail from
Thursday through Saturday. By Sunday, a digging northern stream
trough could lead to light snow showers and reinforce the polar air
across the region for early next week.
As the pattern deamplifies, warmer air will return to the region for
the middle of next week.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1048 PM CDT Tue Apr 1 2025
A band of snow showers will continue to bring IFR conditions to
the region as ceilings lower and visibility gets obstructed by
snow. Kept a TEMPO in the 06Z TAF to account for the heavier bands
expected to move across the region. As we get into Wednesday
morning, snow will gradually change over to a rain/snow mix and
then rain. There is a small chance for some freezing
precipitation, but ice accumulations are expected to be limited
primarily to patchy areas of central and north-central Wisconsin.
Finally, as we get into the afternoon, some thunder may mix into
the area in the afternoon, but coverage will be somewhat isolated.
Maintained a PROB30 for the afternoon chance of thunder but the
window will be limited. All active weather is expected to depart
by the end of the TAF period around 00-03Z Thursday, but some
lower ceilings may still linger in the area.
The active weather will be accompanied by strong winds aloft, with
a jet of 40-55 knots around 2000-4000 feet of the surface, so kept
LLWS in the TAF for any winds that may get closer to the surface.
The latest forecast of 2 to 5 inches of snow still remains on
track for areas north and west of the Fox Valley. This snow will
likely necessitate plowing operations. Ice accumulations around
0.05" to 0.10" will also be possible late tonight into Wednesday
morning, again concentrated mainly to portions of central and
north-central Wisconsin.
&&
.HYDROLOGY...
Issued at 245 PM CDT Tue Apr 1 2025
Rivers continued to level off today from the recent precipitation.
Several locations along the Wisconsin River have fallen below
flood stage, while many others in east-central and far northeast
WI sat at bankfull. While there was improvement with some rivers
leveling off, the additional rainfall expected from this evening
through Wednesday system will cause additional river rises. QPF
amounts of a half inch to an inch are forecast for the next
system, with the highest amounts occurring in areas where rivers
are already seeing impacts.
Higher end QPF amounts up to 1.50" could lead to rivers over
east- central WI moving into minor flood stage. But probabilities
of any river reaching moderate stage is low.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 1 PM CDT Wednesday for WIZ005-
011>013-021-073-074.
Winter Weather Advisory until 1 PM CDT Wednesday for WIZ010-
018>020.
Winter Weather Advisory until 11 AM CDT Wednesday for WIZ022.
Winter Weather Advisory until 9 AM CDT Wednesday for WIZ030-031-
035>037-045.
&&
$$
DISCUSSION.....MPC/MPC
AVIATION.......Uhlmann
HYDROLOGY......MPC
Area Forecast Discussion
National Weather Service Wilmington NC
814 PM EDT Tue Apr 1 2025
.SYNOPSIS...
High pressure will bring onshore flow through Wednesday. The
lingering front to the south will lift back north as a warm
front late Wednesday with much above normal warmth arriving for
Thursday through Sunday. Outside of low rain chances late
Wednesday, the next chance of rain will be late Sunday into
Monday accompanying another cold front.
&&
.UPDATE...
There`s quite a dewpoint gradient across the area from coastal
to inland locations. Shallow Atlantic moisture pushing onshore
behind this afternoon`s seabreeze should push farther inland
overnight, likely yielding a layer of low stratus clouds with
time. There`s already signs of this stratus developing at North
Myrtle Beach where some 600 foot AGL clouds were recently
reported. The largest aerial extend of stratus is expected to
develop inland across the Pee Dee region after midnight.
One more feature of note is a secondary surge of northeasterly
winds making its way down the North Carolina coastline. The
latest HRRR and the 18z NAM show this reaching the coastal
waters before midnight with an increase in wind speeds expected.
I`ve blended in these two models to bring wind speeds up
another few knots, mainly for the NC waters late tonight. The
18z NWPS wave run did not significantly increase forecast sea
heights.
No significant changes have been made to temperatures or sky
cover forecasts overnight.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
The cold front has stalled from along the coast westward through the
Pee Dee region and is demarcating dew points in the low 60s
from those in the low-mid 50s. Cloudiness has largely
dissipated, except in the vicinity of the front along the
coast. Expect the continued advection of low-level dry air and
increasing subsidence aloft to gradually dry out these clouds by
late in the day, leaving a mostly clear sky for this evening
into early tonight. However, as high pressure to the north
shifts offshore, winds will veer to southeasterly tonight and
bring increasing moisture back over the shallow dry air mass
that arrived on Tuesday. This will lead to increasing cloudiness
as stratus clouds develop overnight and spread across the
region. With generally light winds and mainly clear skies this
evening, expect temperatures to drop rather quickly before
slowing down or going steady as easterly winds pick up by
midnight. As stratus clouds arrive, temps will hold steady or
even rise a little where they move overhead during the latter
half of the night. Expect lows generally in the middle 50s,
except low 50s in northeastern portions of the forecast area.
On Wednesday, an anomalous ridge begins building over the
Atlantic near The Bahamas, setting up southwesterly flow
overhead and raising mid-level heights. Near the surface, high
pressure northeast of the area will maintain east to
southeasterly winds through the day, keeping a flow of moist
ocean air into the forecast area over a shallow wedge of
relatively dry air. The end result should be considerable
cloudiness continuing through the day on Wednesday, with
daytime heating helping to eat away at the clouds somewhat,
although just how much clearing can be achieved in the afternoon
carries lower than normal confidence. It is quite possible that
cloudy or mostly cloudy skies remain in place almost
everywhere, which would keep daytime highs somewhat cooler than
forecast. Assuming an initially cloudy morning with mixed clouds
and sun in the afternoon, highs should reach the mid-upper 70s,
except low 70s near the coast. Isolated showers are possible on
Wednesday mainly near the coast, although they should be light
owing to the shallow nature of the moisture and weak forcing.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
Warming will begin in force as lingering boundary lifts back
north as warm front and winds come around to the south with deep
ridge beginning to build across the Southeast. Any low clouds
or light pcp Wed eve into early Thurs should break up. Could
see some afternoon cu, but not expecting any pcp with a very dry
mid to upper level column Thurs aftn onwards.
Rising H5 heights increasing above 590 dam by Thurs will rise
even further. The 850 temps will rise from near 11C to 17C by
Thurs. Overall, summer-like weather with the greatest warmup so
far this season, bringing high temps well into the 80s inland.
The cooler ocean waters will keep temps along the beaches and
closer to the coast cooler, especially with a decent sea breeze
pushing inland in the afternoon. Dewpoints will rebound into the
60s with overnight lows in the mid 60s in a warm and more humid
airmass.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Deep ridging up through the Southeast will slip slowly away
over the weekend into early next week as deep mid to upper
trough pushes a cold front east. Initially rising H5 heights
should peak on Fri and although heights begin to fall through
the weekend, the ridge holds on with continued subsidence and
dry air through the mid levels keeping any showers out of the
picture until at least later on Sun. This will lead to plenty of
sunshine and very warm temps Fri into the weekend with highs
well into the 80s inland and could see our first 90 degree day.
Temps at the beaches will be several degrees cooler as the water
temps were still in the 60s. Expect the cooler 70 degree temps
to spread inland with the sea breeze each aftn. The warm and
more humid air mass will keep overnight lows in the mid 60s
through Sun night.
A deep mid to upper trough will push a cold front into the
Carolinas on Sun. Expect increasing clouds and chc of pcp late
Sun into Sun night. Best shortwave energy will dampen out as it
approaches the eastern Carolinas, but should see shwrs and iso
storms come Mon aftn as front moves through local area. Temps
should only reach into the 70s on Mon with clouds and pcp and by
Mon night into Tues, much cooler air will move in behind front.
Overnight lows Mon night will be down below 50 most places and
highs on Tues only in the 60s.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Winds will veer easterly overnight into Wednesday, bringing a
shallow layer of Atlantic moisture onshore. This could manifest
as early as this evening at KMYR and KCRE where a low to
moderate potential exists for MVFR visibility or MVFR/IFR ceilings
as early as 00z. A moderate to high potential exists after 06z
for MVFR/IFR ceilings to develop inland at KFLO, spreading north
and expanding eastward to include the remainder of the area
with moderate confidence for MVFR ceilings by daybreak
Wednesday. Daytime heating will lift the stratus into cumulus,
but cloud bases may struggle to reach 3000 feet meaning there is
a moderate potential for MVFR ceilings to persist through a
significant portion of the day.
Extended Outlook...MVFR ceilings may linger into Wednesday
evening before clearing to VFR on Thursday.
&&
.MARINE...
Through Wednesday...High pressure north of the forecast area
will maintain steady easterly winds tonight, which will
gradually veer to southeasterly on Wednesday. Seas in the 2-4 ft
range this afternoon increase tonight to 3-4 ft and remain in
that range through Wednesday. Seas will be driven by a
combination of southeasterly swells of 2-4 ft at 8-9 seconds and
easterly wind waves of 1-3 ft at 4-5 seconds.
Wednesday night through Saturday...Winds will transition from SE
to S Wed night into Thurs as warm front lifts north with a
persistent southerly flow setting up through the remainder of
the week. Winds will be in the 10 to 15 kt range and will shift
from S to a more SW direction Fri into the weekend with seas
maintaining a 3 to 4 ft range.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...None.
&&
$$
SYNOPSIS...ILM
UPDATE...TRA
NEAR TERM...ABW
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...TRA
MARINE...RGZ/ABW
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
843 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- A few thunderstorms will develop tonight as a warm front lifts
through the region. The storms will be most numerous along and
northwest of a Springfield to Champaign line where a low
probability (5-15% chance) for hail exists after midnight.
- A more significant severe weather event will unfold on
Wednesday. The latest SPC outlook indicates an Enhanced Risk
(level 3 of 5) for damaging wind gusts, large hail, and
tornadoes.
- Multiple rounds of showers and thunderstorms will lead to a risk
for excessive rainfall and flooding issues along and south of
I-70...where a Flood Watch is in effect from Wednesday afternoon
through Sunday morning.
&&
.UPDATE...
Issued at 842 PM CDT Tue Apr 1 2025
Low pressure is located over Kansas late this evening with a broad
region of mid level warm air advection overspreading much of the
mid and upper Mississippi Valley ahead of the low. This is driving
scattered showers and a few storms across portions of central
Illinois. Latest RAP indicates pockets of around 900 J/kg MUCAPE
rooted around 750 mb is advecting into the area as well supporting
some pockets of deeper convection. In fact, RAP indicates very
steep (in excess of 8 C/km) mid level lapse rates are in place
which in combination with relatively low (around 8 kft) freezing
levels will support some small hail in the strongest storms.
Instability will continue to increase overnight with around 1500
J/kg MUCAPE by daybreak Wednesday. A few isolated hailers will
continue to be a concern through the night with a gradual increase
in threat for marginally severe hail, mainly late tonight.
Deubelbeiss
&&
.DISCUSSION...
Issued at 346 PM CDT Tue Apr 1 2025
Showers and thunderstorms associated with a warm front lifting into
the area early Wednesday morning will develop overnight, with
elevated instability steadily increasing to several hundred J/kg by
sunrise, which could allow a few storms with large hail to one inch
diameter to develop north of I-72. Forecast soundings show a near
surface stable layer which should prevent a threat of severe wind
gusts at the surface, except perhaps west of a Springfield to Peoria
line if a convective complex to the west is able to maintain
strength as it rolls into western portions of central IL. This
activity should diminish across much of central IL from the late
morning into early afternoon, allowing instability to re-develop, at
least for portions of central and southeast IL. East of I-55 appears
to have more certainty of severe thunderstorm activity developing in
the afternoon, with tornadoes, locally damaging winds, and large
hail possible. To the west, CAMs are not as unanimous with
convective development or significant surface-based CAPE.
Nevertheless, there is a conditional threat for severe
thunderstorms, and SPC has an Enhanced Risk designated for the
entire area, with a threat for a few strong tornadoes centered south
of I-72, and a threat for 2+ inch hail, and 75+ mph wind gusts over
the entire area. While average precipitation amounts don`t appear to
be impressive, generally a half inch, CAMs suggest a threat for
localized 2 inch corridors in stronger storms and WPC has a Marginal
to Slight Risk for excessive rainfall from near I-55 eastward.
Timing of re-development remains uncertain, but earliest appears to
be 1-2 PM and latest 4-6 PM, with similar uncertainty in location,
perhaps well west of the IL River, or perhaps well east of I-55.
As the associated low pressure system deepens and lifts into the
upper Midwest Wednesday, strong pressure gradients will develop into
central IL and mixing aloft will deepen as the warm front lifts
north of the area. Strong momentum aloft will begin to mix down, to
the surface, and it appears 45 to 50 mph gusts will develop. Current
indications are that areas east of I-55 should develop strong winds
by mid morning and have the higher gusts during the day, but it may
take until after noon for areas west of I-55. Winds should diminish
after the associated cold front sweeps eastward across the area. A
Wind Advisory has been issued for the entire area...noon to 7 pm
west of I-55, and 8 AM to midnight east of I-55.
The next few days should see the frontal boundary stall out near the
Ohio River, with a series of disturbances propagating along the
boundary bringing a threat of extreme rainfall if the heaviest
rainfall falls in the same general tracks. At this point, rainfall
looks to be focused on southeast IL Thursday night, central and
southeast IL Friday afternoon into Friday night, and southeast IL
Saturday into Sunday. A Flood Watch is in effect from around I-70
southward, with an outlook for 6-7 inches of total rainfall
Wednesday through Saturday night. North of I-72, rainfall amounts of
1 to 3 inches are expected.
Temperatures should be mild into the weekend, but cooler air looks
to arrive following the active weather period, bringing a threat of
sub-freezing lows by early next work week.
37
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 614 PM CDT Tue Apr 1 2025
A deepening area of low pressure will lift from the central Great
Plains this evening to the Upper Midwest Wednesday evening. Strong
southeast winds currently in place will gradually veer to the SSW
by around midday Wednesday with gusts gradually increasing,
peaking near 40kt during the afternoon. LLWS is also expected at
times overnight into Tuesday morning as winds just above the
surface increase above 50 then 60 kt. There will be several waves
of showers and storms possible through the period, though
confidence in specific timing remains low. The strongest storms
are expected Wednesday afternoon and will likely produce swaths of
severe weather in the region. The best chance for these severe
storms will be SPI-DEC-CMI with lesser chances farther northwest
at PIA and BMI.
Deubelbeiss
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from noon to 7 PM CDT Wednesday for ILZ027>031-036-
037-040>042-047>051.
Wind Advisory from 8 AM Wednesday to midnight CDT Wednesday
night for ILZ038-043>046-052>057-061>063-066>068-071>073.
Flood Watch from Wednesday afternoon through Sunday morning for
ILZ062-063-066>068-071>073.
&&
$$
Area Forecast Discussion
National Weather Service North Platte NE
607 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Strong system moves into the area tonight with chances for
showers and isolated thunderstorms. A few strong
thunderstorms this evening across southeastern areas.
- Snow chances late tonight into Wednesday morning across the
northern Sandhills. Northwest winds 20 to 35 mph across the
area by Wednesday afternoon.
- Below normal highs Thursday through Saturday, with chances for
mainly rain showers each day.
&&
.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 403 PM CDT Tue Apr 1 2025
The upstream portion of a main upper trough over the Western
U.S. has begun to move into western Nebraska this afternoon.
Deep surface low pressure was currently centered over northwest
Kansas, and is about 100 miles further south that what was
forecast yesterday. This will focus most of the stronger storms
to our east across south central and southeast Nebraska late
this afternoon and evening.
Shower chances will increase early evening, with a few strong storms
possible across the far eastern counties, mainly east of a
Moorefield through Broken Bow and Ewing line. Most unstable CAPEs in
this area will be modest at 100 up to 500 J/KG. Storm motion will be
northeast at 35 to 40KT. A few storms will be capable of hail up to
1 inch diameter and strong thunderstorm wind gusts through mid
evening. The latest runs of the HRRR are largely dry, except for
shower development across the panhandle into the western Sandhills
this evening, with discrete storms to our east in south central and
southeast Nebraska. The CAMs show more coverage across the
southeastern half of the forecast area. Overall POPs are mostly near
40 percent tonight. A cold front moves in during the evening and
overnight, with the closed upper low moving from far southwest
South Dakota into north central Nebraska. Colder air drawn into
the backside of the system will bring the potential for snow
across the northwest Sandhills, with any higher accumulations
up to a half inch confined to the Pine Ridge.
On Wednesday, a closed upper low over far northern Nebraska at 12Z
will track fairly quickly into west central MN by late afternoon.
Looks dry across southwest Nebraska, with snow chances across north
central Nebraska. Light snow accumulations to a tenth or two are
possible across northern Nebraska, though the better accumulations
again across the Pine Ridge at up to a half inch. Becoming
windy across the area, as northwest winds increase to 20 to 35
mph by afternoon. Highs cooler from the low 40s north, to 50 to
55 south.
Wednesday night, the area will be in between systems, as a large
upper trough persists across the Pacific Northwest into the Desert
Southwest. A closed upper low near the Four Corners will bring
precipitation into Colorado overnight. Will see skies becoming mostly
clear overnight across western Nebraska, as weak high pressure
builds in. Lows will be colder in the low to mid 20s.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 403 PM CDT Tue Apr 1 2025
On Thursday, a lead disturbance in southwest flow aloft over eastern
CO and western KS will lift into southwestern areas during the
afternoon and bring a chance for showers. Shower chances increase
Thursday night, with likely POPS across the southwest and central
Sandhills. large upper trough will extend across the Great Basin,
with southwest flow aloft across Nebraska.
Friday afternoon and Friday night, the flow aloft becomes more
amplified to south southwest. PWATs increase to 125 to 175
percent of normal across the southeastern half of the area.
Saturday, precipitation should quickly end during the morning as the
upper trough axis moves across. Dry conditions expected Saturday
night through Tuesday.
Highs will remain below normal in the mid to upper 40s Thursday
through Saturday, followed by a warming trend Sunday through
Tuesday. Highs Monday are forecast to reach the low 60 across the
west, with low to mid 70s by Tuesday.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 607 PM CDT Tue Apr 1 2025
MVFR ceilings are expected at the KLBF terminal tonight into
Wednesday morning with -SHRA possible this evening. IFR ceilings
at KVTN tonight into Wednesday morning with -SHRA possible
after 04Z tonight, with 2SM -SHSN 12Z-15Z Wednesday. Northwest
winds increase by 12Z at both terminals to near 30019G28KT after
15Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Roberg
LONG TERM...Roberg
AVIATION...Roberg
Area Forecast Discussion
National Weather Service Marquette MI
742 PM EDT Tue Apr 1 2025
.KEY MESSAGES...
- Another strong system passes over the region late tonight
through Wednesday. Prepare for slick roads on Wednesday with
potential power outages.
- Precipitation starts off as snow, but a wintry mix begins late
morning/early afternoon before transitioning over to mainly
all rain by late afternoon. Widespread 1-2 inches of wet snow
with up to 4-5 inches in the Keweenaw and south central U.P.
- Gusty winds are expected up to 35-45 mph, especially Wednesday
afternoon in the high terrain, east, and Keweenaw.
&&
.SHORT TERM /THROUGH TODAY/...
Issued at 117 PM EDT Tue Apr 1 2025
Early afternoon RAP analysis has midlevel ridging extending from the
Canadian Prairies to the Upper Midwest, supporting surface high
pressure centered downstream over eastern Ontario. On the back side
of the surface high, light winds remain out of the south across the
Upper Peninsula. Under sunny skies, temperatures are rebounding
nicely from morning lows in the teens and single digits across much
of the UP. Temperatures generally range in the lower to mid 30s so
far, and should be able to peak in the mid/upper 30s for today.
Expect a gradual increase in southerly winds through the afternoon
and evening as a deep surface low ejects out of the Rockies, leading
to a steepening pressure gradient over the Great Lakes. This system
will bring rounds of wintry precipitation to the area overnight into
Wednesday - more on that below.
&&
.LONG TERM /TONIGHT THROUGH TUESDAY/...
Issued at 420 PM EDT Tue Apr 1 2025
The main focus of the fcst starts tonight and continues through Wed,
as a strong low pressure system brings gusty winds and a wintry mix
of precip to the UP. A negatively tilted mid level trough over the N
half of the Plains becomes more amplified tonight through Wed,
tracking over the Upper Great Lakes late in the day Wed into Thu.
This supports a strong sfc low from W KS to Upper MI by Wed night.
There is high confidence for this to start off as sn along the WI/MI
state line between midnight and 2 AM EDT tonight with isentropic
ascent slowly expanding sn to the NE. PoP coverage weakens not long
after outside the S central, despite the increasing support from WAA
as the deep moisture above 10-15kft drops off late tonight. Lift is
then maximized mid morning into the afternoon as the right entrance
region of the 130kt jet lifts over the UP coupled with strong WAA.
Drier air in the W will be a limiting factor for this second round,
but better moisture is expected over the E. A wintry mix including
fzra/pl/ra begins to mix in from the S mid day, transitioning over
to primarily ra by the late afternoon as temps warm into the mid to
upper 30s; some spot may reach 40 in downslope areas of the W. As
mentioned earlier, a dry slot over the W favors drier periods into
the afternoon/evening but CAMs are not in great agreement on
timing/placement. Increasing f-gen aloft does look to increase PoPs
in the W late on Wed as -shra progress E over the UP. Given some
limited elevated instability, a few rumbles of thunder are possible
but not included in the going fcst. With wet snowfall of SLR`s
around 10:1, widespread 1-2" of snow is expected with up to 4-5"
over the S central and Keweenaw by Wed afternoon. This will lead to
some slick road conditions impacting the Wed morning commute. Ice
accumulations for most will be limited to a light glaze, however a
few hundreths of ice cant be ruled out.
Outside the wintry precip, gusty east-southeast winds are expected
during the day as well ~35-45 mph. Strongest winds are expected
during the afternoon where Wind Advisory criteria may be met in the
Keweenaw, far east, and in areas of SSE downslope flow for a few
hours. Gusts diminish into the evening hours as the low pressure
system moves overhead, but increase out of the W to NW or Thu around
25-35 mph. As the low tracks over W Upper MI Wed night, drier air
expands over the E. Marginally cold enough 850mb temps wrap around
the system into Thu, and with the support of upslope flow, yield
some -shsn over the NW wind snow belts (mainly far W UP). Additional
accumulations hold less than 1". High pressure and decreasing
cyclonic flow aloft gradually returns dry weather to the UP on Thu.
A trough over the Canadian Prairie on Thu amplifies on Fri,
extending into the N Plains. This troughing is anticipated to pivot
over the Upper Great Lakes late in the weekend through Mon, bringing
back some -shsn to the UP on Sat. This transitions over to pure LES
shsn Sun night as 850mb temps drop to around -18C.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 742 PM EDT Tue Apr 1 2025
System approaching the region tonight will result in increasing
clouds, lowering ceilings, strong winds, low level wind shear, and
increasing probabilities for precipitation. Strong winds of 25kts
develop tonight and peak at 30-40kts during the day Wednesday,
highest at KCMX. First wave of snow will build in tonight lifting
northeastward, followed by a second wave of snow by morning. This
second wave will shift to rain by afternoon as it continues to lift
through the region, potentially mixing by freezing rain or sleet
late morning/early afternoon. Ceilings will fall to MVFR and then
IFR as precip continues through the day. LIFR can`t be ruled out at
KCMX/KSAW by afternoon.
&&
.MARINE...
Issued at 420 PM EDT Tue Apr 1 2025
East to southeast winds around 20 kts or less this afternoon
gradually increase to 20-30 kts through tonight with gales of 35-40
kts by Wednesday morning as a low pressure system approaches from
the southwest. On Wednesday, high end gales to 40-45 kts are
expected across much of the lake with storm force winds to 50 kts
over the east half, particularly along the international line. Winds
drop off into Wednesday evening down to 30-45 kts as the low
pressure moves over western Upper Michigan. Winds fall further to 20-
30 kts Wednesday night as the low pressure moves over the lake,
quickly wrapping around out of the west at 20-30 kts. There is a 40-
70% chance for gales to 35 kts over the east half of the lake on
Thursday.
Expect waves to build up to 12-20ft by late Wednesday afternoon
highest over the north central third of the lake. Waves settle back
down to 4-8ft by Thursday as winds drop off and turn out of the west.
The pressure gradient slackens into Thursday night as the system
departs to the northeast, allowing west to northwest winds to settle
below 20 kts. Winds are expected to remain mainly below 20 kts
through much of this weekend.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Winter Weather Advisory from 2 AM to 8 PM EDT Wednesday for
MIZ001-003.
Winter Weather Advisory from midnight EDT /11 PM CDT/ tonight
to 2 PM EDT /1 PM CDT/ Wednesday for MIZ010>013.
Winter Weather Advisory from 8 AM to 5 PM EDT Wednesday for
MIZ014.
Lake Superior...
Gale Warning from 5 AM EDT /4 AM CDT/ to 8 PM EDT /7 PM CDT/
Wednesday for LSZ162-263.
Gale Warning from 5 AM to 6 PM EDT Wednesday for LSZ243-
247>250.
Gale Warning from 2 AM to 8 PM EDT Wednesday for LSZ244>246-
265.
Gale Warning from 5 AM to 11 PM EDT Wednesday for LSZ251.
Gale Warning from 2 AM to 11 AM EDT Wednesday for LSZ264-266-
267.
Storm Warning from 11 AM to 5 PM EDT Wednesday for LSZ264-266-
267.
Lake Michigan...
Gale Warning from 6 AM to 5 PM EDT Wednesday for LMZ221-248-
250.
&&
$$
SHORT TERM...LC
LONG TERM...Jablonski
AVIATION...JTP
MARINE...Jablonski
Area Forecast Discussion
National Weather Service Nashville TN
829 PM CDT Tue Apr 1 2025
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 750 PM CDT Tue Apr 1 2025
- Major flooding may develop for northwest Middle Tennessee with
heavy rainfall at times Wednesday evening through Sunday
morning. Stewart, Montgomery, and Houston Counties are at
greatest risk with 6 to 10 inches of rainfall expected. Flash
flooding and eventually river flooding will be concerns across
the northwest half of Middle Tennessee.
- There will be a risk for severe storms across the area at times
Wednesday evening through Saturday. The main risk area will be
over the northwest half of Middle Tennessee. The risk is very
"conditional" as thunderstorms may stay focused along the
frontal zone northwest of our area. If storms do spread farther
southeast into the Mid State, they may contain damaging winds
and torrential downpours. Although less of a risk, large hail
and tornadoes cannot be ruled out. It will be important to
monitor forecast updates frequently for the latest information.
&&
.SHORT TERM...
(Tonight through Thursday Night)
Issued at 750 PM CDT Tue Apr 1 2025
Tonight is going to be the last quiet night of weather we can
expect for quite some time. A surface ridge has already slipped
across Middle Tennessee, with winds now turning southeastward.
Expect winds to increase considerably from the south tomorrow as
the pressure gradient tightens up ahead of an approaching cold
front. Winds tomorrow will increase to the point that a Wind
Advisory has been issued for expected gusts of 35-45 mph. In
addition, 850 mb winds look to increase to 60-65 kts by tomorrow
afternoon, setting up a highly efficient moisture transport that
will help increase our Precipitable Water values well above the
90th percentile climatologically. The 18Z HRRR brings a line of
storms into the northwest corner of Middle Tennessee around 02Z
tomorrow evening, and up to Nashville by around 06Z, and then the
activity won`t go much farther. Also, storms look to weaken some
as they progress eastward through Middle Tennessee, so the severe
potential for areas to the east and south of Nashville are
probably minimal for tomorrow and tomorrow night. In fact, many
locations won`t see any showers at all until Thursday or later. As
storms weaken tomorrow evening and overnight, we will transition
from a severe threat to more of a flooding threat. Indeed, this
opening round of active weather may produce some robust rainfall
totals right off the bat, with echo training likely to occur
across areas to the northwest of Nashville. By 12Z Thursday, the
aforementioned cold front will become quasi-stationary just
northwest of Middle Tennessee. Obviously, rainfall amounts will
be greatest closer to the boundary, then taper off considerably.
This means there will be quite the rainfall gradient across Middle
Tennessee throughout this event. Meanwhile, the severe potential
will continue on Thursday and Thursday night, although to a lesser
extent than on Wednesday night.
&&
.LONG TERM...
(Friday through next Wednesday)
Issued at 750 PM CDT Tue Apr 1 2025
The quasi-stationary boundary won`t go away anytime soon. It
appears to be held at bay buy a strong Bermuda High and persistent
ridging over the southeast U.S. So the SPC keeps a severe
potential in place across Middle Tennessee for Friday and
Saturday, as well. With little air mass change in coming days, we
can expect daytime temperatures well above seasonal normals with
dew points staying put in the 60s until the front comes through
this weekend. With the front stalled to our northwest, several
impulses will ride up the wave, thereby creating several rounds of
active weather between tomorrow night and Saturday night. It is
difficult at this point to address any timing questions beyond
tomorrow night and early Thursday. It is also difficult to
ascertain just how deeply the severe storms and flooding will
extend into Middle Tennessee. It`s safe to say that areas to the
north and west of Nashville can expect a high potential for both
river and areal flooding. Storm total QPF values range from 6-10"
across this region. At this time, river models are only beginning
to pick up on the initial QPF. Once we get deeper into the event,
we can expect significant rises on rivers and streams. Also, there
is the uncertainty of boundary placing itself. If the quasi-
stationary boundary were to set up farther east than what is
currently projected, more areas in Middle Tennessee would be
adversely impact. And if the boundary sets up farther west, then
the reverse would be true. Either way, we may very well wind up
with a scenario where locations north and west of Nashville
experience significant flooding and severe storms, and areas along
the Cumberland Plateau experience very little active weather
until the weekend. Finally, the surface high pressure will begin
to relent by Saturday, allowing for the quasi-stationary boundary
to finally pick up some steam and push through Middle Tennessee
Saturday night and Sunday, thereby bringing this multi-day weather
event to a close. Temperatures on the back side of the front will
be considerably cooler. In fact, several mid state locations may
be in for some frosty weather Tuesday morning and again Wednesday
morning.
&&
.AVIATION...
(00Z TAFS)
Issued at 614 PM CDT Tue Apr 1 2025
Overall we will see VFR conditions for the TAF period. High clouds
start to build in later this evening and we will see lower cigs
after 13z. These cigs are expected to remain in VFR but could fall
into MVFR for a short time. Cigs will start to come back up by
18z. A low level jet will develop tonight and that will bring wind
shear 40-50 knots out of the south. Surface winds under 10 knots
this evening gradually increasing overnight and becoming gusty
tomorrow after 13z with gusts up to 34 knots.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 58 85 68 83 / 20 30 70 70
Clarksville 55 83 65 76 / 30 50 90 90
Crossville 49 75 64 82 / 10 10 30 40
Columbia 56 84 68 84 / 10 20 60 60
Cookeville 53 79 67 82 / 10 20 50 50
Jamestown 49 77 65 83 / 10 10 50 50
Lawrenceburg 56 83 68 84 / 10 20 40 40
Murfreesboro 54 85 68 85 / 20 20 50 50
Waverly 56 82 64 76 / 30 40 90 90
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 10 AM Wednesday to 4 AM CDT Thursday for
TNZ005>011-023>034-056>066-075-077>080-093>095.
Flood Watch from Wednesday evening through Sunday morning for
TNZ005>011-023>031-056>060-062-093.
&&
$$
SHORT TERM...Rose
LONG TERM....Rose
AVIATION.....Mueller
Area Forecast Discussion
National Weather Service Pueblo CO
905 PM MDT Tue Apr 1 2025
.KEY MESSAGES...
- Winds will slowly diminish late this afternoon and this evening.
- Still some bursts of wind/snow along the Continental Divide this
evening, ending by early Wed morning
- High fire danger returns to Fremont County and the southern
I-25 corridor Wed morning.
- Active weather pattern brings snow and rain across south central
and southeast Colorado Wednesday night into Thursday afternoon.
- Higher confidence (60-80 percent) in higher impact weather for
Friday night and Saturday, with heavy, wet snowfall across the
SE Mtns and Raton Mesa.
- Warmer and drier weather late weekend into early next week.
&&
.UPDATE...
Issued at 903 PM MDT Tue Apr 1 2025
Update to allow Winter Weather Advisories for lower elevations
of Lake and Chaffee Counties, along with the San Juan Mountains,
to expire as scheduled. Snowfall rates have decreased below
Advisory levels across these areas. For this reason, the Winter
Weather Advisories were expired as scheduled. Winter Weather
Advisories continue until 6 AM for higher elevations of Lake and
Chaffee Counties.
&&
.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 258 PM MDT Tue Apr 1 2025
Upper level jet over srn Colorado this afternoon will shift south
and east this evening as short wave trough lifts eastward through
the central Rockies. Strong/damaging winds under the jet have
been rather spotty so far, though ALS/TAD/LAA have all gusted over
50 kts as of midday, and many areas have seen 40-50 kt gusts. HRRR
and surface obs (50 mph gusts along I-25 south of PUB) suggest one
more pulse of stronger winds possible 2-4 pm, so reluctant to take
the High Wind Warning down at this point, though suspect an early
cancellation is still likely after 4 pm as jet moves away and winds
drop-off by early evening. Isolated showers have served to moisten
the boundary layer around PUB and COS, keeping min RH above the 15
percent critical fire weather threshold so far, while areas south
and east have dried out enough to verify the Red Flag Warning. Will
keep warning going into early evening, as bulk of the area will see
critical conditions. Wind and snow along the Continental Divide will
continue into the evening, then conditions improve slowly after
sunset as wave moves away, leading to diminishing winds/snowfall.
Dry air mass will lead to near/below freezing mins at most
locations, despite winds staying breezy through the night.
On Wednesday, main concern is return of critical fire weather
conditions along I-25, especially from mid-morning into early
afternoon, as very dry air mass spreads across the region. Winds
will be marginal, but HRRR and a good deal of statistical guidance
suggest 25-30 mph gusts through the Arkansas Valley from Canon
City to Pueblo, and from La Veta Pass east to Walsenburg, mainly in
the 15z-21z time frame. Will hoist a Red Flag Warning for I-25 from
Pueblo south and include Fremont County as well, though won`t spread
anything farther north and east, as winds drop off quickly enough in
the afternoon to keep the 3 hr duration threshold from being met.
wanes. Air mass back toward the Continental Divide moistens slightly
toward late afternoon as next upper wave approaches, and expect a
few showers over mainly the higher peaks by 00z. Looks too dry
farther east for any activity, at least during the daytime hours.
Sun and mixing will tend to offset cooling mid-level temps, leading
to maxes in the seasonably cool 40s/50s/60s.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Issued at 258 PM MDT Tue Apr 1 2025
Wednesday night through Thursday night...Latest model data supports
a broad upper trough digging across the West Coast and into the Great
Basin, with short wave energy lifting out across southwestern Colorado
into northeastern through the day Thursday. Induced lee low across the
southeast plains leads to moderate east to northeast sfc-h7 flow, as
moisture and uvv increase across the region leading to widespread
precipitation developing over and near the higher terrain Wednesday
night, spreading north and east through the day Thursday before
winding down late Thursday afternoon and evening as said wave continues
across to move north and east of the area. Snow levels are likely below
4000 feet into early Thursday morning before rising back to near 6500
feet Thursday afternoon, there is the potential for snowfall of 3 to 6
inches across the Contdvd into the higher elevations of the Pikes Peak
region and SE Mtns, with 1 to 3 inches possible across the Upper Arkansas
River Valley, the San Luis Valley, and the Wet Mtn Valley into the I-25
Corridor, with little or no snow expected across the southeast Plains.
With that said, may need winter weather advisories across portions of
the higher terrain, with the potential for travel impacts for the
Thursday morning commute.
Friday-Saturday...There is increasing confidence of higher impact
weather in the Friday night and Saturday timeframe, especially
across the higher terrain south of the Highway 50 Corridor, and
northern portions of the Pikes Peak region, as the main upper low
digs south across southern New Mexico Friday night before lifting
out across western Texas on Saturday. Pattern supports widespread
precipitation developing across the region within modest southerly
flow aloft Friday night, with the focus of moderate to heavy snow
fall shifting from the southwest mtns into the southeast mtns
through the day Saturday. Developing north to northeast flow aloft
may also bring a period of moderate to locally heavy snowfall
to the higher terrain of the Pikes Peak and Palmer Dvd region Friday
night. The amount of cold air associated with this system still needs
to worked out, though current forecast brings up to a foot of snow
across the eastern San Juans through the Sangres and Wets, with 4
to 8 inches across the rest of the higher terrain into the Palmer
Dvd and Raton Mesa through the day Saturday. Those with travel plans
across the higher terrain should stay abreast of weather through
the early weekend.
Sunday-Tuesday...Models support upper level ridging building across
the region, supporting warmer and drier weather in the offing for the
late weekend into early next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 535 PM MDT Tue Apr 1 2025
VFR conditions are expected at all three TAF sites, KCOS, KPUB, and
KALS, for the next 24 hours. West winds are likely (80% chance) to
continue to weaken across the area as we get closer to sunset.
Expecting gusts to weaken below 40kt shortly after 00Z at KPUB, with
gusts below 25kt at KCOS and KALS after 02Z. West to northwest winds
remain elevated through the overnight hours, though gusts are likely
(80% chance) to remain under 30kt throughout the rest of the
overnight period and into our Wednesday as well. Winds weaken
further after 21Z Wednesday. Mid-level cloud cover looks to
persist off and on throughout the period.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 AM MDT Wednesday for COZ058-
060.
Red Flag Warning from 9 AM to 6 PM MDT Wednesday for COZ222-
228>230.
&&
$$
UPDATE...EHR
SHORT TERM...PETERSEN
LONG TERM...MW
AVIATION...EHR
Area Forecast Discussion
National Weather Service Shreveport LA
953 PM CDT Tue Apr 1 2025
...New UPDATE...
.UPDATE...
Issued at 949 PM CDT Tue Apr 1 2025
Light precipitation has just about ended across our region this
evening as the isentropic forcing that resulted in the development
of light showers across our region earlier seems to have ended.
Still going to hang onto slight chance pops however to the south
and east of the I-30 Corridor just in case some light
precipitation tries to develop once again before sunrise.
Likewise, held onto chance pops across our far northwest zones
even though latest HRRR suggests that any strong to severe
convection will likely remain north and west of our northwestern
most zones prior to sunrise. Latest hourly ambient temperatures
are in the ballpark with forecast hourly temps so no temperature
changes are warranted with this evening`s forecast.
No update necessary for the remainder of the evening.
13
&&
.UPDATE...
Issued at 644 PM CDT Tue Apr 1 2025
Just sent a quick update to the forecast to account for the
widely scattered showers which have developed across portions of
Central and Northern Louisiana as well as Northeast Texas. This is
in an areas of increased isentropic forcing, something of which
the HRRR has a pretty good handle on. Thinking that this will
dissipate later this evening and should not continue through the
late night hours but will address this possibility with the
routine updated forecast later this evening.
New zone package has been sent...13.
&&
.SHORT TERM...
(This evening through Wednesday Night)
Issued at 240 PM CDT Tue Apr 1 2025
A warm front continues to surge northward across the region this
afternoon, setting the stage for a prolonged period of unsettled
weather throughout the remainder of this week. This includes both
severe weather and excessive heavy rainfall, increasing the risk
of flash flooding and eventually some river flooding as the week
progresses.
For the short-term forecast period from tonight through tomorrow
night, SW flow aloft will continue to be reinforced in advance of
the first in a series of shortwave disturbances moving through the
flow pattern. This initial shortwave will lift NE generally north
of the I-30 corridor late this evening and overnight with a very
low-end severe potential just encroaching into our extreme NE TX
zones along the Red River and adjacent areas in McCurtain County
in SE OK. This is mainly to account for threat of isolated large
hail and damaging wind gusts that many accompany any storms that
develop and track eastward along the Middle Red River Valley. For
the vast majority of the region outside of the aforementioned
areas, expect a quiet night with well above normal temperatures
given the increasing southerly winds. Speaking of those winds,
they will become stronger and gusty overnight but should remain
below advisory thresholds.
Moving ahead to Wednesday, that initial shortwave will continue to
pivot NE into the Mid-MS Valley while a cold front slowly advances
across the Central and Southern Plains. This front should remain
west of our entire region through most of the day, maintaining a
vast warm sector across much of the South Central U.S. Significant
destabilization is expected ahead of the front with afternoon high
temperatures expected to range from the upper 70s to mid 80s while
dew points hover in the mid to upper 60s. This will push sfc-based
CAPE into the 2500-3000 J/kg range during peak heating times with
severe thunderstorms potentially developing by early/mid afternoon
across NW zones and gradually expand SE through late afternoon and
early evening. This is illustrated in the updated Day 2 convective
outlook from SPC with a rather expansive Enhanced Risk highlighted
across roughly the NW two-thirds of our region and tapering back
to Slight or Marginal Risk farther SE where forcing and influence
from the sfc boundary won`t be as pronounced. This will be an all
modes severe threat, including the potential for very large hail
and a few higher end tornadoes (EF2+) for much of the Enhanced
Risk area.
The severe threat should begin to diminish with time by late in
the evening and overnight as heating is lost and the boundary
becomes stalled invof or just north of I-30. This will prove to be
rather impactful in terms of the forecast going forward into the
long-term period as the daily threat of severe weather and heavy
rainfall loom further into the mid to late week timeframe.
/19/
&&
.LONG TERM...
(Thursday through next Monday)
Issued at 240 PM CDT Tue Apr 1 2025
As mentioned, the stalled sfc boundary will take up residence near
the I-30 corridor and effectively park itself there for the
remainder of this week and possibly early into the weekend. The
end result will be a period of very unsettled weather with daily
severe weather probabilities along with a significant increase in
the threat of heavy rainfall and flash flooding, especially for
areas along and north of I-30. For purposes of the Flood Watch,
did not make any changes to the earlier issuance of the Watch but
it is certainly possible that some additional areas in NE TX and
SW AR could be added based on the latest model trends which
indicate as much as 3-6 inches of rainfall down to the AR/LA
border with higher amounts farther north in the current Watch
area. Keep in mind this will be spread out over several days with
multiple rounds of showers and storms expected through at least
Saturday night or early Sunday.
Beyond the Saturday night and early Sunday timeframe, the front
will finally gain some much needed upper-level support and be
ushered eastward by late in the weekend with much cooler and drier
weather expected by early next week. In fact, temperatures should
run well below normal by Sunday night and especially for early
next week in the post-frontal air mass in place. This will give
us a much needed period to dry out after several days of rainfall.
/19/
&&
.AVIATION...
(00Z TAFS)
Issued at 649 PM CDT Tue Apr 1 2025
For the 02/00z TAF update...Radar imagery is showing some light
showers across central Louisiana this evening. Shouldn`t see any
impact to any of our terminals at this time but will continue to
monitor it. Satellite imagery is showing some lower clouds across
the region this evening as well. This has been bringing some MVFR
conditions to some terminals at times and I am expecting this
trend to continue into the rest of the evening and some of the
overnight hours before improving around 02/18z. Winds have
remained gusty across the region this evening and this also is
expected to continue into the overnight hours. /33/
&&
.SPOTTER INFORMATION STATEMENT...
Issued at 409 AM CDT Tue Apr 1 2025
Spotter activation should not be needed through tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 71 85 73 87 / 20 60 60 70
MLU 71 86 73 88 / 20 30 50 40
DEQ 64 78 62 75 / 50 80 90 100
TXK 70 82 68 82 / 20 90 90 100
ELD 67 84 67 83 / 20 80 80 80
TYR 71 81 71 84 / 20 60 60 70
GGG 69 82 70 85 / 20 60 60 80
LFK 70 84 73 88 / 20 30 20 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Flood Watch from late Wednesday night through Sunday morning for
ARZ050-051-059>061.
LA...None.
OK...Flood Watch from late Wednesday night through Sunday morning for
OKZ077.
TX...Flood Watch from late Wednesday night through Sunday morning for
TXZ096-097.
&&
$$
SHORT TERM...19
LONG TERM....19
AVIATION...33
Area Forecast Discussion
National Weather Service Topeka KS
641 PM CDT Tue Apr 1 2025
.KEY MESSAGES...
- Thunderstorms are expected to develop this evening and overnight,
with the potential for severe weather. Large hail, damaging winds,
and tornadoes are all possible with these storms.
- Gusty south winds with some occasional 45mph gusts remain possible
into late this evening.
- Temperatures trend cooler and below average late this week into
early next week.
&&
.DISCUSSION...
Issued at 252 PM CDT Tue Apr 1 2025
A 988mb surface low pressure system has developed along the KS/CO
border in response to a lead perturbation ejecting out of the
broader upper troughing pattern encompassing the western CONUS.
Moisture has been slowly advecting northward with 50+ dew points
having made it into south central KS and 60+ dew points still along
and south of the Red River Valley as of 19Z. Moisture transport
should happen more quickly later this afternoon and especially into
the early evening as the LLJ starts to pick up.
As we head into the evening and overnight hours, there are two areas
of convective initiation and evolution that we`ll need to monitor.
The first is with more isolated supercells that may develop along a
sharpening dryline in south central KS and move northeastward into
east central KS, and the second is with storms developing in north
central KS as the cold front eventually catches up to the dryline.
The HRRR has consistently been the most aggressive solution, and the
18Z run has even started to develop some initial supercells in north
central KS before they congeal into a line later tonight. Starting
with the isolated cells further south, there remains lower
confidence in these storms having much of an impact on east central
KS. This is due to the fact that they would be moving into a less
favorable environment for surface-based storms as they move further
north and east into the open warm sector. Even so, plentiful shear
exists in the environment to keep any storm going that develops.
While coverage of storms would be isolated with anything that comes
from south central KS or northern OK, if a storm can maintain itself
as it moves into our area, this would pose the greatest risk for a
strong tornado, as well as large hail and damaging wind. Timing for
this aspect of the severe weather threat could be as early as 7pm,
but probably mostly in the 8-11pm time frame.
The most probable impact we are monitoring is associated with the
second area described above. Again, the HRRR has recently become the
most robust in developing some discrete cells initially around 00-
01Z as the cold front catches up to the dryline. As we get closer to
03-04Z, storms should grow upscale into a line and move east through
the overnight hours, likely not reaching far eastern areas until
after 4am. Wind damage would likely be the main threat with these
late night storms, but cannot rule out a brief tornado spinning up
along the leading edge of the line as it develops into a QLCS. This
is especially the case earlier on in the event towards north central
KS, whereas further east the line should weaken with time. Storms
should exit the area around sunrise.
The broad upper troughing pattern remains in place through the end
of the week, and some perturbations within that pattern keep some
additional rain chances particularly on Friday into Saturday. A cold
front Saturday into Sunday looks to usher in a much cooler air mass
late this week into early next week. Morning lows could dip near or
below freezing Sunday and Monday.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 636 PM CDT Tue Apr 1 2025
Multiple aviation hazards will be present during the 00Z TAF
period as a strong system impacts the area. A LLJ will increase
to 50-55 kts this evening, which could create LLWS when gusts
are not occurring at the surface. Thunderstorms then become
likely, especially after midnight, moving from west to east.
There could be some lingering showers behind the main line of
storms tonight, but rain should exit the area by around sunrise
Wednesday. West winds will then become gusty Wednesday
afternoon.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 1 AM CDT Wednesday for KSZ008-KSZ009-
KSZ010-KSZ020-KSZ021-KSZ022-KSZ023-KSZ034-KSZ035-KSZ036-KSZ037-
KSZ038-KSZ054.
&&
$$
DISCUSSION...Picha
AVIATION...Teefey