wi discuss
Office: MKX
FXUS63 KMKX 040246
AFDMKX
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
946 PM CDT Fri May 3 2024
.KEY MESSAGES...
- A few stronger thunderstorms are possible in southeast WI
Saturday afternoon.
- Additional showers and thunderstorms are expected during the
middle portions of next week.
&&
.UPDATE...
Issued 927 PM CDT Fri May 3 2024
Some stratus may move in from Lake Michigan Saturday morning,
impacting far eastern Wisconsin. Then some sun is expected there
midday before clouds return with the frontal passage. No changes
to the shower and thunderstorm chances for Saturday. See
previous discussion.
Marquardt
&&
.SHORT TERM...
Issued 351 PM CDT Fri May 3 2024
Tonight through Saturday night:
Clear skies will prevail over southern WI tonight. Look for
winds to become light and variable overnight as high pressure
moves across the region, then start increasing out of the
southeast in the morning as the high departs. Dewpoints mixed
down to around 40 this afternoon, so that should help our
evening temps drop into the lower 50s quickly. Lows should be in
the upper 40s, but can't rule out mid 40s toward central WI.
A line of showers and thunderstorms along a weak cold front will
be tracking into the western part of WI Saturday morning. This
front is associated with a mid level shortwave trough and the
resultant weak surface low. The stronger forcing with that
shortwave will stick closer to the entrance region of the upper
jet, which will track across northwest WI. Therefore, the line
of showers with a chance for lightning will be weakening as it
tracks into south central WI late Saturday morning.
Once the front reaches south central WI from around Janesville
to Fond du Lac, there will have been enough daytime heating to
allow for some build-up of CAPE (up to 1000 j/kg) in southeast
WI to support an increase in shower and thunderstorm
development. The shear is on the higher end and will be enhanced
by the lake breeze. While the mid level forcing will be weaker,
the surface forcing will be stronger. Thus, there is a chance
for a stronger storm or two in far southeast WI during the
afternoon. Small hail and gusty winds are the threats. The
tornado threat is non-zero if storms interact just right with
the lake breeze boundary. The window of opportunity looks like
3 to 8 PM for areas between Janesville, Port Washington, and the
WI/IL border.
Cronce
&&
.LONG TERM...
Issued 351 PM CDT Fri May 3 2024
Sunday through Friday:
High pressure will take hold of southern WI Sunday and Monday.
Look for increasing southeast winds Mon afternoon as low
pressure approaches from the Plains. That closed low will stay
fairly stationary in the Northern Plains Mon-Tue as it occludes,
but showers and thunderstorms along the warm front should
extend into southern WI on Tuesday. As the upper low either
moves eastward or weakens, another round of showers and storms
is possible over southern WI on Thursday. The weather pattern
associated with the storm chances is complicated and
unorganized, which is the typical nature of upper lows. Expect
changes to the forecast many times between now and then.
Unfortunately, that upper low does not move out of the Upper
Midwest until at least Saturday, which means a prolonged period
of clouds and precip chances for southern WI until then.
Cronce
&&
.AVIATION...
Issued 927 PM CDT Fri May 3 2024
Some clouds may move in from Lake Michigan Saturday morning
impacting far eastern Wisconsin, including MKE. Cloud bases
could be scattered to broken around 1000ft for a few hours from
10 to 14Z before rising and scattering. There is a lot of
uncertainty whether this will occur and VFR could prevail.
East winds will become south and gust around 20 knots during
the day Saturday for areas inland of Lake Michigan. A line of
scattered showers and thunderstorms will be weakening as it
moves into south-central Wisconsin late Saturday morning. Once
it reaches Janesville to Fond du Lac more widespread showers an
thunderstorms are expected to develop late Saturday afternoon
and early evening.
Marquardt
&&
.MARINE...
Issued 351 PM CDT Fri May 3 2024
Light southeast winds are expected tonight into Saturday as high
pressure slides across the Upper Great Lakes. Showers and
thunderstorms are possible along a cold front late Saturday
afternoon through the evening. High pressure will return for
Sunday and Monday. The next low pressure system that may bring
gusty winds below gale level and another round of thunderstorms will
track across northern Lake Michigan Tuesday into Wednesday.
Cronce
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&
$$
Visit us at weather.gov/milwaukee
Follow us on Facebook, Twitter, and YouTube at:
www.facebook.com/NWSMilwaukee
www.twitter.com/NWSMilwaukee
www.youtube.com/NWSMilwaukee
Office: ARX
FXUS63 KARX 040413
AFDARX
Area Forecast Discussion
National Weather Service La Crosse WI
1113 PM CDT Fri May 3 2024
.KEY MESSAGES...
- Showers and scattered storms are expected mainly Saturday.
Rainfall amounts of up to a half of an inch from the showers
or storms.
- Active pattern develops next week with periodic showers and
storms through much of next week. Timing of convection into
region remains an issue and will have impacts on the severe
potential across the forecast area.
&&
.DISCUSSION...
Issued at 226 PM CDT Fri May 3 2024
Today through Saturday:
While quiet weather is in store for the rest of the day, guidance
continues to support a shortwave moving through the area on
Saturday. Accompanying this wave will be a 30 to 40kt 850mb jet
that will help to increase the moisture transport. PWATs will
increase into the 1 to 1.3 inch range. Recent guidance continues
to show some instability moving further north, as shown by
general consensus of 250 to 500J/kg of SBCAPE. The highest
instability continues to be in southern Wisconsin. Despite this
instability, it is not enough to promote any severe weather,
even with the high amounts of shear, 30 to 50kts of 0-6km bulk
shear. This means that thunderstorms will be possible as the
band of precipitation moves through the morning and early
afternoon on Saturday.
Sunday into Monday
Shortwave ridge builds into the Upper Great Lakes Region Sunday into
Monday. Subsidence underneath ridge will allow for mainly dry
weather across the forecast area both days. With light winds near
the surface...clear skies and an inversion developing over the
forecast area Saturday night/Sunday morning. There is the
possibility of fog formation across parts of the area...mainly in
low lying areas/river valleys. However...if northwest winds stay up
enough...fog may not form. At this time...have left mention of fog
out of the forecast.
Warmer airmass advects into the region Sunday into Monday...as 925mb
temperatures warm from around plus 10 degrees celsius Sunday to near
plus 14 degrees celsius by 00z Tuesday. High temperatures will be
mainly in the 60s Sunday and warming into the upper 60s to middle
70s Monday.
Monday night through Friday
Main forecast concerns from Monday night through Friday continues to
be shower/storm chances through much of the forecast period. Upper
level closed low slowly moves over the Northern Plains States and
weakens during the forecast period. Latest ensembles/deterministic
models continue to show differences in timing of the upper level
closed low/impulses rotating around the closed upper level low into
the Upper Mississippi River Valley. Confidence in timing of
convection and any severe potential with the storms remains low. The
latest GFS/ECMWF continue to indicate vertical motion/moisture
convergence with the closed upper level low/impulses. This will
produce periodic showers/storms through much of the forecast
period...Monday night into Friday. Temperatures will remain near or
slightly above normal with highs generally in the lower 60s to
middle 70s through the forecast period.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1113 PM CDT Fri May 3 2024
VFR conditions look to continue through the overnight. Showers
and perhaps a few thunderstorms will begin to move into the area
towards the morning hours. Have maintained the previous
forecasts trend with ceilings as guidance continues to indicate
a period of MVFR. A few models suggest ceilings could lower to
IFR for a time, especially at KRST, but confidence remains a
bit lower so have opted to hold with MVFR and monitor
trends/observations. Some reductions in visibility may be
possible at times with heavier rainfall as well. Otherwise,
light winds will begin to shift more northwest through the day.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...DTJ
AVIATION...EMS
Office: GRB
FXUS63 KGRB 040329
AFDGRB
Area Forecast Discussion
National Weather Service Green Bay WI
1029 PM CDT Fri May 3 2024
Updated aviation portion for 06Z TAF issuance
.KEY MESSAGES...
- Scattered showers and isolated thunderstorms are expected
Saturday into Saturday evening, with additional showers and
thunderstorms Tuesday through Wednesday.
- A few rivers will remain at or reach bankfull stage into the
weekend.
&&
.DISCUSSION...
Issued at 340 PM CDT Fri May 3 2024
Short Term...Tonight and Saturday
Deep mixing allowed temperatures to soar into the middle 60s to
lower 70s, caused winds to gust to 25 to 35 mph over far N WI, and
resulted in pockets of low relative humidity in the sandy soil
regions of northern and central WI this afternoon.
Mostly clear skies will give way to a gradual increase in mid and
high level clouds overnight, but dry conditions will prevail.
Considered the possibility of patchy fog overnight, but a well-
mixed air mass, increasing boundary layer winds overnight and
shorter spring night argued against any mention at this time. Look
for low temperatures to drop into the 40s.
On Saturday, a dry start to the day will give way to a band of
light to moderate showers along and ahead of a cold frontal
passage. The showers will be aided by a weak surface wave lifting
northeast along the front, plus upper divergence in the RRQ of a
110 kt jet streak and weak short-wave energy. There is a general
consensus for a narrow ribbon of weak instability (SBCAPE 200-400
j/kg) developing over the Fox Valley and lakeshore areas in the
afternoon, so have kept a mention of a few thunderstorms there.
Showers should arrive in NC/C WI mid to late morning, and Fox
Valley/lakeshore early to mid afternoon. High temperatures will
range from the upper 50s and lower 60s west and near Lake
Michigan, to 65 to 70 across inland areas of NE/EC WI.
Long Term...Saturday Night Through Friday
Saturday evening/night...Rain and a few thunderstorms will be
ongoing across far eastern WI into Saturday evening as a cold front
and mid-level shortwave tracks over the area. Not anticipating for
these storms to be strong or severe as the couple hundred J/kg of
instability over the area during the afternoon will rapidly decrease
into the evening. The showers and storms will exit the state by 06z
Sunday.
Sunday through Monday...High pressure and upper-level ridging moves
over the area during this time period, leaving dry weather and
mostly sunny skies across the forecast area. Temperatures will rise
above normal for both days with highs ranging from the mid 60s to
low 70s inland, and upper 50s to low 60s along the lakeshore.
Slightly elevated fire weather conditions are possible on Monday as
afternoon RH values will be in the 30s and southeast winds may gust
to 20 to 25 mph. Locations across the north would be of greatest
concern where green up has not fully occurred.
Rest of the extended...Models are still in agreement with an upper-
level trough developing over the Northern Plains Monday into
Tuesday. This will leave the forecast area in the southerly flow
ahead of the trough, allowing southern stream energy and moisture to
increase and lift into the Middle and Upper Mississippi Valleys.
Although there are still some timing and placement differences,
especially when the precip will end, Tuesday into Tuesday evening
appears to be the best timing for widespread rain and embedded
thunderstorms. Despite being in the warm sector, the timing of the
precip may hinder severe potential across the forecast area and keep
it confined south of the area. Will continue to monitor as there is
still plenty of time for the details to be ironed out over the
coming days. Details for the remainder of the extended become very
messy, but models agree with additional chances for precip at times
through the rest of next work week.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1028 PM CDT Fri May 3 2024
Expect VFR conditions to prevail through midday Saturday, with
patchy mid/high clouds expected into early Saturday. Thickening
and lowering clouds are expected in NC/C WI as showers arrive
toward midday and C/NE WI Saturday afternoon. Some thunderstorms
are possible, but chances are low enough to leave out of the TAFs.
Conditions will deteriorate to MVFR Saturday afternoon as the
showers arrive, then improve back to VFR Saturday evening as the
showers end and skies scatter out. Considered the possibility of
patchy fog overnight, but the air mass was well mixed this
afternoon (warm temps and low dew points leading to large dew
point depressions) and boundary layer winds will be increasing to
20 to 25 kts late tonight. Models are hinting at some low clouds
coming off Lake Michigan (near MTW) Saturday morning, but
confidence is too low to mention a ceiling at this time.
Light SE surface winds are expected overnight, then moderate SE-S
later Saturday morning and SW Saturday afternoon turning NW
Saturday evening.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION.....Kieckbusch/Kruk
AVIATION.......Kurimski
