Special Weather Statement, NWS Milwaukee, WI

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
655 PM CDT Mon Aug 5 2019

.UPDATE...

Storms are still cellular over central WI and southeast MN. They
are producing damaging winds and a few cells have had large hail.
It's still uncertain as to whether or not they will evolve into
more organized line segments as they roll through southern WI
later this evening, but bulk 0-6km shear around 40 kt and ML CAPE
axis around 2000 j/kg leaning into the northwest MKX forecast area
(Sauk, Marquette, Green Lake, Columbia counties) suggests that the
ongoing convection should hold together just long enough to impact
this area. As the storms get further into south central and
southeast WI late this evening, there will be less instability and
shear to support severe storms. The latest SPC Mesoscale
discussion basically says we will be waiting on issuing a watch
for now and continue to watch the trends.

&&

.AVIATION(00Z TAFS)...

Thunderstorms will roll through south central and southeast WI
this evening. Expect them to exit far southeast WI just after
midnight. Damaging winds and large hail are possible toward
central WI, including Baraboo to Fond du Lac and Sheboygan. Then
gusty winds are likely with the thunderstorms (but probably not
damaging) as they get into southeast WI. Madison is still an
uncertain area- we will have to see if the storms hold together by
the time they reach there.

MVFR ceilings are likely early Tuesday morning, along with some
patchy fog in low lying areas and river valleys. Clouds will
gradually break up and lift through late morning. Northerly winds
are expected Tuesday, with a lake breeze developing by noon.

&&

.PREV DISCUSSION... (Issued 305 PM CDT Mon Aug 5 2019)

SHORT TERM...

Tonight and Tuesday...Forecast confidence medium.

Low to mid level warm, moist advection will increase into the
evening ahead of a shortwave trough that will track from nw WI
into Lower MI late tnt. This will bring a thermal ridge and mid
level lapse rates of 6.5-7.0 C/KM into area with a weak cool front
to follow. The MLCAPE will likely rise to 1500-2000 J/KG just
ahead of the convection that will eventually merge from srn MN
into central and nrn WI. Deep layer shear will be a little
stronger than earlier thought with values up to 35 kts. Either
way, there will be enough shear and resultant outflows to organize
the convection into a line. North to south movement of the line
through the evening hours is expected with a SVR threat of
damaging winds especially over south central WI. Some showers and
storms may linger into the overnight with small chances of tstorms
continuing through Tue due to the passage of another weak
shortwave trough. Areas of stratus and fog will likely occur Tue
AM but burn off by afternoon.

Tuesday Night Through Wednesday...Forecast Confidence is Medium.

There is a slight chance for a few showers/storms Tuesday night but
will be heavily dependent on available forcing from the shortwave
pulling through and corresponding moisture. Most of the models
suggest it may be too dry in the mid levels behind the system with
relatively weak forcing from the shortwave in the upper levels.
Thus we expect the area to remain mostly dry.

On Wednesday, another front is expected to roll through the region
potentially bringing showers/storms to parts of the CWA. There is a
bit of uncertainty here as well due to the location of the best
forcing and moisture and the timing for when the front rolls
through. Some shortwave energy will pull through the area in
addition to the front Wednesday afternoon/evening. The uncertainty
with location of potential showers/storms is due to the better
forcing and moisture being located further north. The models
continue to show disagreement in timing and location of
precipitation but the best chance for showers/storms will be in the
northern parts of the CWA during the late afternoon/early evening.

LONG TERM...

Thursday Through Sunday...Forecast Confidence is Medium...

Thursday and Friday looks to be mostly quiet as high pressure builds
in behind the front that will come through Wednesday. Saturday will
start dry but an upper level shortwave may push through bringing the
potential for showers/storms as the high looks to push out a bit
earlier than previously expected. At this point the system looks to
track to the north possibly clipping the CWA but it remains a bit
early to tell what the track/timing of this system may be. Sunday and
Monday look to remain mostly dry but there is quite a bit of
uncertainty given differences in the models and the potential for
slight deviations in the current forecast to yield potential for
showers/storms.

AVIATION(21Z TAFS)...Sct-bkn045-060 cumulus and cumulus congestus
this afternoon into the evening. A line of tstorms will move south
through central and srn WI through the evening with lingering
showers and storms possible during the overnight. Areas of stratus
and fog will then occur for the early morning hours of Tue and
dissipate by late morning on Tue. Areas of Cigs of 600-3000 feet
are expected with vsbys of 1-4SM. More sct-bkn035-040 cumulus and
cumulus congestus for Tue afternoon and slight chances of tstorms.

MARINE...High pressure of 30.0 inches over the east coast of the
United States will weaken this afternoon and tonight while low
pressure of 29.6 inches remains over Hudson Bay into the middle of
the week. Modest southwest winds this afternoon will gradually
shift westerly tonight with the passage of a weak cool front.
Light and variable winds will return for Tuesday and Tuesday
night. Modest southwest winds will develop on Wednesday and shift
northwesterly late Wednesday night and Thursday due to a cold
frontal passage.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

Update...Cronce
Tonight/Tuesday and Aviation/Marine...Gehring
Tuesday Night through Monday...ARK

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>