Marine Thunderstorm Wind in Lake Michigan, August 13, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
339 AM CDT SAT AUG 13 2011

.UPDATE...ADDED DENSE FOG ADVISORY FOR PARTS OF THE CWA THROUGH 9
AM CDT.

TODAY AND TONIGHT...FORECAST CONFIDENCE...MEDIUM

SOME FOG..ESPECIALLY RIVER VALLEYS EARLY THIS MORNING...BUT SHOULD
IMPROVE AS MORE CLOUDS AND PCPN MOVE IN FROM MN.

A STRONG SHORTWAVE TROUGH WILL BE SWINGING ACROSS THE UPPER MIDWEST
TODAY STRAIGHT FOR WI.  MODELS DIFFER ON SOLUTIONS...BUT ALL HAVE
VARYING AMOUNTS OF PRECIP...SHOWERS AND STORMS. PURE EXTRAPOLATION
AND PER HRRR MODEL...THE BAND OF CONVECTION AT 08Z FROM TWIN CITIES
TO NORTH-CENTRAL IA WILL SWING IN SOUTHERN WI BETWEEN 10Z AND 13Z.
SOME SCATTERED STUFF WILL OCCUR AHEAD OF THE MAIN BAND...AND ALREADY
HAS JUST NORTH OF MADISON.

LOCAL WRF MODEL /WRF4L/ SUGGESTS AN ADDITIONAL CONVECTIVE COMPLEX
DEVELOPING OVER NORTHEASTERN IOWA AND SOUTHWESTERN WI BY
14Z...REACHING MADISON AREA BY 18Z...AND EXTRAPOLATION WOULD CARRY
IT EAST WITH UPPER TROUGH IN THE AFTERNOON. THIS ACTIVITY WAS ALSO
SUGGESTED IN PREVIOUS FORECAST.

WRAP-AROUND BANDS OF MOISTURE AND INSTABILITY HANG AROUND INTO EARLY
SATURDAY NIGHT AS VORTICITY LOBES/SPOKES ROTATE AROUND UPPER TROUGH
WHICH MAY CLOSE OFF BRIEFLY PER NAM MODEL. WILL KEEP CHANCES OF
SHOWERS AND STORMS GOING UNTIL ABOUT MIDNIGHT TONIGHT...BUT END PCPN
WESTERN HALF OF MY COUNTY WARNING AT 06Z. SOME FOG AGAIN TONIGHT
MADISON AND WEST.

SUNDAY - CONFIDENCE...MEDIUM
UPPER LOW PROGGD TO BE IN LOWER MI AT START OF THE DAY WITH
LINGERING VORT LOBE SHIFTING SOUTHEAST OF WI EARLY IN THE DAY. 850
COLD POOL WILL BE IN PLACE WITH STEADY NNE WINDS THROUGH MIDDAY. 850
TEMPS OF AROUND 11C TRANSLATE TO DELTA T VALUES OF 11C WHICH IS
MARGINAL FOR LAKE INDUCED PRECIP. BUFKIT SOUNDINGS SHOW LAKE INDUCED
CAPE OF AROUND 800 J/KG WITH EQUILIBRIUM LEVELS OVER 30K FEET. PROGS
SUGGEST LIGHT QPF BRUSHING THE FAR EAST SUNDAY MORNING THOUGH 00Z
SUITE OF MODELS NOT AS IMPRESSIVE AS 24 HOURS AGO ON THIS IDEA.
ANTICYCLONIC VORTICITY ADVECTION TAKES HOLD TOWARDS MIDDAY INTO THE
AFTERNOON. 850 COLD POOL LINGERS INTO THE AFTERNOON THOUGH SOME
MODERATION NOTED WITH TRAJECTORIES BECOMING LESS FAVORABLE.

MONDAY - CONFIDENCE...MEDIUM
UPPER LEVEL ANTICYCLONIC FLOW PATTERN WITH LARGE SURFACE HIGH
PRESSURE EXPECTED TO RESULT IN A DECENT DAY. GFS AND NAM BOTH SHOW
LIGHT QPF THOUGH BUFKIT SOUNDINGS QUITE DRY WITH A CAP AROUND
650/700 MILLIBARS. WILL STICK WITH THE SINGLE DIGIT MOS POPS/DRY
FORECAST AT THIS POINT AS THIS LOOKS MORE REFLECTIVE OF OVERALL
SYNOPTIC CONDITIONS.

TUESDAY - CONFIDENCE...LOW TO MEDIUM
PROGS SHOW SHORTWAVE RIDING TO OUR SOUTHWEST THROUGH THE RIDGE.
ENHANCED 850 LOW LEVEL JET FOCUSES TO OUR SOUTHWEST WITH MOST IF NOT
ALL OF PRECIP MISSING US TO OUR SOUTHWEST WITH THIS WAVE. MAIN UPPER
DYNAMICS WELL OFF TO THE WEST IN THE PLAINS...SO CONCEIVABLE WE END
UP WITH A DRY DAY THOUGH CONSENSUS WAS TO LEAVE THE SMALL ALLBLEND
POPS IN PLACE. IN FACT 00Z ECMWF SHOWS THE SHORTWAVE EVEN FURTHER
SOUTHWEST OF HERE LENDING GREATER CONFIDENCE TO A DRY FORECAST.

TUESDAY NIGHT THROUGH WEDNESDAY EVENING - CONFIDENCE...LOW
VIGOROUS UPPER SYSTEM WILL BE TRACKING FROM THE DAKOTAS TO NORTH OF
LAKE SUPERIOR THIS PERIOD. MODELS SHOWING VARYING SOLUTIONS WITH
RESPECT TO TIMING AND COVERAGE OF FRONTAL CONVECTION. AT THIS TIME
THE GEM-NH AND GFS ARE IN BETTER AGREEMENT ON QPF AND TIMING...WHILE
THE ECMWF IS QUITE MEAGHER AND A BIT SLOWER. PRETTY DECENT MOIST
AXIS BUBBLING UP AHEAD OF THE 850 FRONT. 700-500 LAPSE RATES ARE
7.0-7.5C/KM. 0-6KM BULK SHEAR AT 40 KNOTS. SEEING A BIT OF UPPER
DIVERGENCE IN CONJUNCTION WITH NOSE OF 250 MILLIBAR JET. LOTS OF TIME
BEFORE THIS EVENT BUT COULD END UP HAVING SOME SEVERE POTENTIAL WITH
IT.

THURSDAY AND FRIDAY - CONFIDENCE...LOW
CONSENSUS AMONG OFFICES WAS TO LEAN TOWARDS THE DRIER LOOK OF THE
ECMWF WITH HIGH PRESSURE IN CONTROL IN THE WAKE OF THE FRONT. GFS
QUICKLY BRINGS ANOTHER TROUGH INTO THE UPPER MIDWEST WHILE THE ECMWF
ALLOWS A RIDGE TO BUILD UP BEFORE THE NEXT WAVE ARRIVES INTO THE
WEEKEND. SO FOR NOW SIDING WITH THE DRIER ECMWF.

&&

.AVIATION...LIGHT WINDS AND MOIST BOUNDARY LAYER AND BREAKS IN CLOUD
COVER HAVE ALLOWED MVFR FOG TO DEVELOP OVER MUCH OF SOUTHERN
WI...LOCALLY IFR. THESE CONDITIONS SHOULD END AS CLOUD AND
CONVECTION MOVE IN FROM MN AND IA THIS MORNING. EXPECT MVFR CONDS
WITH A BAND OF STORMS MOVING WEST TO EAST BETWEEN 10Z AND 14Z ACROSS
SOUTHERN WI...FOLLOWED BY A CONVECT COMPLEX DEVELOPING OVER
SOUTHWESTERN WI BY 14Z. THIS COMPLEX WILL MOVE TO EASTERN WI AFTER
ABOUT 17/18Z. CIGS AND VSBYS WILL YO-YO THROUGH TODAY INTO TONIGHT
WITH EACH ROUND OF SHOWERS AND STORMS. SOME OF THIS ACTIVITY WILL
PERSIST INTO TONIGHT AS UPPER TROUGH SWINGS THROUGH. MORE MVFR FOG
POSSIBLE TONIGHT MADISON AND WEST...MAYBE IFR IN RIVER VALLEYS.
SURFACE WINDS TO STAY UP ABOVE 10 KNOTS IN EASTERN WI TONIGHT...SO
NO FOG IN THE EAST.

&&

.MARINE...WINDS AND WAVES WILL INCREASE AS NORTH TO NORTHEAST WINDS
OF 15 TO 25 KNOTS COME DOWN THE LAKE BEHIND A DEPARTING LOW PRESSURE
SYSTEM SATURDAY EVENING...REACHING THE WINTHROP HARBOR AREA BY 09Z.
SMALL CRAFT ADVISORY CONDITIONS WILL THEN PERSIST TO 00Z MON.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ046-047-
     051-056>058-063.

LM...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM CDT SUNDAY FOR LMZ645-646.

     SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT SUNDAY
     FOR LMZ643-644.

&&

SHORT/LONG TERM...COLLAR
TODAY/TONIGHT/AVIATION/MARINE...KAPELA

<!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>

<!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>