Severe Thunderstorm Warning 93, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 PM EDT TUE AUG 19 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 330 PM EDT TUE AUG 19 2014

THUNDERSTORMS WITH HEAVY RAIN AND GUSTY WINDS WILL EXIT TONIGHT AS A
COLD FRONT PASSES THROUGH BUT A FEW SCATTERED SHOWERS WILL LINGER
TONIGHT AND WEDNESDAY.

A STRONG WARM FRONT WILL APPROACH FROM THE SOUTHWEST THURSDAY AND
THURSDAY NIGHT. THIS FRONT MAY TRIGGER ANOTHER ROUND OF HEAVY
THUNDERSTORMS... FOLLOWED BY VERY WARM AND HUMID CONDITIONS FOR THE
UPCOMING WEEKEND.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 330 PM EDT TUE AUG 19 2014

ACTIVE WEATHER WILL CONTINUE OVER THE NEXT FEW HOURS AS APPROACHING
COLD FRONT OVER ERN WI INTERACTS WITH VERY MOIST AND UNSTABLE AIR
MASS OVER SRN LWR MI. CAPES ARE 1500-2000 SOUTH OF I-96 WITH UPR 60
DEW PTS AND PWATS AROUND 1.7. THERE HAVE BEEN SOME REPORTS OF
TORRENTIAL RAIN WITH MORE THAN TWO INCHES AN HOUR... SO URBAN AND
SMALL STREAM FLOODING IS A THREAT IN ADDITION TO THE THREAT FOR
SEVERE/WX DAMAGING WINDS.

RAIN CHANCES DECREASE LATER THIS EVENING AFTER FROPA BUT AS THE
UPPER LOW OVER WRN UPR MI MOVES TO NRN LK HURON LOOK FOR SCATTERED
SHOWERS TO PERSIST. THESE MAY PERK BACK UP TO TSTMS ON WEDNESDAY
AFTERNOON WITH HEATING...PARTICULARLY OVER NRN AND ERN LWR MI. A
LAKE SHADOW WILL PROBABLY DEVELOP FOR WEDNESDAY AFTERNOON WITH NW
LOW LEVEL FLOW SO WILL FEATURE A DRY AFTERNOON FOR THE COASTAL
COUNTIES WHILE GOING WITH LIKELY POPS FOR CLARE... MT PLEASANT...
AND ALMA AREAS.

BEST POPS IN LATER PERIODS LOOKS TO BE THURSDAY NIGHT AS THE WARM
FRONT/LOW LEVEL JET SHIFT TOWARD THE AREA. GUIDANCE...ESPECIALLY THE
ECMWF...LOOKS RATHER AGGRESSIVE SO THERE COULD BE A ROUND OF STRONG
STORMS WITH HEAVY RAINFALL.

.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 330 PM EDT TUE AUG 19 2014

IT WOULD SEEM WE DO ACTUALLY HAVE A CHANCE OF SEEING HIGHS NEAR OR
ABOVE 90 DEGREES OVER A GOOD PART OF OUR CWA THROUGH THE WEEKEND
INTO EARLY NEXT WEEK. AS THE WARM AIR SURGES IN WE WILL LIKELY HAVE
SOME SIGNIFICANT RAINFALL (STRONG THUNDERSTORMS) FRIDAY POSSIBLY
INTO SATURDAY.  THE NEXT THREAT OF THUNDERSTORMS IS MONDAY NIGHT
INTO TUESDAY AS A COLD FRONT MOVES INTO THE AREA.

THE MODELS ARE IN GOOD AGREEMENT ON THE BUILDING OF A SIGNIFICANT
UPPER LEVEL RIDGE OVER THE EAST CENTRAL SECTIONS OF THE CONUS THIS
COMING WEEKEND. THIS IS IN RESPONSE TO STRONGLY DIGGING UPPER LOW
OVER THE PACIFIC NORTHWEST IN THE SAME TIME FRAME. A SIGNIFICANT
SLIT IN THE UPPER LEVEL JET WILL KEEP THE COLD AIR NORTH JAMES BAY
THROUGH THE WEEKEND. THE ONLY REAL ISSUE WITH THE LONG RANGE
FORECAST IS HOW QUICKLY THE UPPER LOW EJECTS INTO THE PLAINS.
TYPICALLY THE MODELS DO THIS TO QUICKLY. ALREADY THE MODELS HAVE
SLOWED DOWN NEARLY A DAY WITH THE COLD FRONT COMING THROUGH.

MY FORECAST HIGHS ARE BASED ON MY 1000/925 MB THICKNESS TOOL...WHICH
ARE LARGELY 2 TO 4 DEGREES ABOVE MOST OF THE MOS NUMBERS. GIVEN
CLIMO WOULD HAVE AN IMPACT ON THOSE NUMBER... HAVING HIGHS INCREASED
SEEMS LIKE A GOOD IDEA. THAT BEING SO WE MAY SEE OUR FIRST 90+ HIGHS
SAT...SUN AND MON.  I HAVE 90 ON SAT FOR NOW BUT I WOULD THINK IT IS
MORE THAN LIKELY SUNDAY AND MONDAY TOO.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 154 PM EDT TUE AUG 19 2014

A RATHER COMPLEX FORECAST THIS AFTERNOON AND INTO TONIGHT AS AN
BAND OF CONVECTION AHEAD OF THE COLD FRONT SLOWLY MOVES THROUGH
THE TAF SITES THIS AFTERNOON INTO THIS EVENING. THEN THE ISSUE
TURNS TO FOG DEVELOPMENT OVERNIGHT.

THE SLOW MOVING LINE OF THUNDERSTORMS SEPARATES THE VFR CONDITIONS
FROM MVFR/IFR CIGS AND VSBY. AS THE LINE SLOWLY MOVES EAST MVFR
CIGS WILL LINGER. AS THE STORMS MOVE THROUGH THE TAF SITES IFR
VSBY ARE EXPECTED WITH WIND GUSTS TO 35 KNOTS MORE THAN POSSIBLE. THE
CLEAR SKIES OVER LK MI WILL LIKELY NOT MOVE INLAND.

ONCE THE LINE CLEARS THE AREA AFTER 00Z I EXPECT MOSTLY MVFR CIGS
AND DUE TO THE WIDESPREAD RAIN... FOG AND LOW CEILINGS IS EXPECTED
AFTER MIDNIGHT. IT IS QUESTIONABLE AS TO HOW MUCH CLEARING THERE
WILL BE WEDNESDAY AS THE FRONT DOES NOT GET TO FAR SOUTH OF
MICHIGAN. MEANING OUR TAF SITES WILL BE NEAR THE FRONTAL ZONE.

&&

.MARINE...
ISSUED AT 330 PM EDT TUE AUG 19 2014

GENERALLY WEAK GRADIENT EXPECTED SO WINDS AND WAVES SHOULD REMAIN
BELOW SMALL CRAFT CRITERIA. HOWEVER AREAS OF FOG WILL BE A
POSSIBILITY AS HUMID AIR INTERACTS WITH THE COOLER LK MI WATERS.

&&

.HYDROLOGY...
ISSUED AT 330 PM EDT TUE AUG 19 2014

HEAVY RAINFALL RATES OF 1-2 INCHES PER HOUR THROUGH EARLY EVENING
WILL SUPPORT A THREAT OF URBAN AND SMALL STREAM FLOODING. SCATTERED
NATURE OF THESE HEAVIER AMOUNTS SHOULD LIMIT EXTENT OF RISES ON THE
LARGER RIVERS. THE PATTERN LATER IN THE WEEK SUPPORTS ADDITIONAL
HEAVY RAINFALL EVENTS SO RIVER FLOODING COULD BECOME MORE OF A
CONCERN BY THAT TIME.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...MEADE
MARINE...MEADE

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1255 PM EDT TUE AUG 19 2014

LMZ844>849-MIZ037>040-043>046-050>052-056>059-064>067-071>074-
200930-
ST JOSEPH TO SOUTH HAVEN MI-SOUTH HAVEN TO HOLLAND MI-
HOLLAND TO GRAND HAVEN MI-GRAND HAVEN TO WHITEHALL MI-
WHITEHALL TO PENTWATER MI-PENTWATER TO MANISTEE MI-MASON-LAKE-
OSCEOLA-CLARE-OCEANA-NEWAYGO-MECOSTA-ISABELLA-MUSKEGON-MONTCALM-
GRATIOT-OTTAWA-KENT-IONIA-CLINTON-ALLEGAN-BARRY-EATON-INGHAM-
VAN BUREN-KALAMAZOO-CALHOUN-JACKSON-
1255 PM EDT TUE AUG 19 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST LOWER
MICHIGAN.

.DAY ONE...TODAY AND TONIGHT

SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING SOUTH
AND EAST OF GRAND RAPIDS... INCLUDING KALAMAZOO... BATTLE CREEK...
LANSING AND JACKSON. THE THREAT IS DAMAGING WINDS AND/OR LARGE HAIL
AS WELL AS LOCALLY HEAVY RAINFALL. THE PRIMARY TIME OF CONCERN IS
FROM 1 PM TO 7 PM.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THUNDERSTORMS ARE EXPECTED WEDNESDAY AND AGAIN ON THURSDAY NIGHT
AND FRIDAY. SEVERE WEATHER IS NOT EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EARLY EVENING.

MEADE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1232 PM EDT TUE AUG 19 2014

MIZ056-057-064-191715-
ALLEGAN-KENT-OTTAWA-
1232 PM EDT TUE AUG 19 2014

...SIGNIFICANT WEATHER ADVISORY...

AT 1231 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR DRENTHE...MOVING EAST AT 45 MPH.

PEA SIZE HAIL...WIND GUSTS GREATER THAN 40 MPH...OCCASIONAL CLOUD TO
GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THIS
STORM.

* THE THUNDERSTORM WILL BE NEAR...
  HUDSONVILLE BY 1240 PM EDT...
  DRENTHE BY 1235 PM EDT...
  JAMESTOWN BY 1240 PM EDT...
  BYRON CENTER BY 1245 PM EDT...
  CUTLERVILLE BY 1250 PM EDT...
  DUTTON BY 1255 PM EDT...
  ALASKA BY 100 PM EDT...
  CASCADE BY 105 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW
AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK
SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS PASSED.

&&

LAT...LON 4282 8614 4299 8539 4277 8537 4277 8554
      4271 8555 4261 8620
TIME...MOT...LOC 1633Z 252DEG 39KT 4277 8589

HOVING

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
109 PM EDT TUE AUG 19 2014

MIZ046-051-052-056>059-064>067-071>074-191915-
ALLEGAN-BARRY-CALHOUN-CLINTON-EATON-GRATIOT-INGHAM-IONIA-ISABELLA-
JACKSON-KALAMAZOO-KENT-MONTCALM-OTTAWA-VAN BUREN-
109 PM EDT TUE AUG 19 2014

...SIGNIFICANT WEATHER ADVISORY...

AT 106 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM MOUNT PLEASANT TO
VAN BUREN STATE PARK...MOVING EAST AT 30 MPH. THESE STORMS MAY
BECOME SEVERE THIS AFTERNOON...AND ADDITIONAL STORM DEVELOPMENT IS
LIKELY THROUGH THE EVENING.

PEA SIZE HAIL...WIND GUSTS GREATER THAN 40 MPH...OCCASIONAL CLOUD TO
GROUND LIGHTNING...BRIEF HEAVY DOWNPOURS...ARE POSSIBLE WITH THESE
STORMS.

LOCATIONS IMPACTED INCLUDE...
  SOUTH HAVEN...        GREENVILLE...         ALLEGAN...
  ALMA...               IONIA...              HASTINGS...
  KALAMAZOO...          ST. JOHNS...          BATTLE CREEK...
  CHARLOTTE...          LANSING...            STANTON...
  BELDING...            BANGOR...             LOWELL...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW
AROUND. STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK
SHELTER IN A STURDY STRUCTURE UNTIL THESE STORMS HAVE PASSED.

&&

LAT...LON 4207 8622 4224 8623 4224 8637 4248 8626
      4362 8477 4362 8460 4347 8460 4347 8436
      4278 8436 4277 8415 4207 8413
TIME...MOT...LOC 1708Z 287DEG 27KT 4362 8477 4239 8639

HOVING

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
149 PM EDT TUE AUG 19 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0140 PM     HEAVY RAIN       2 S ROCKFORD            43.09N 85.56W
08/19/2014  M1.20 INCH       KENT               MI   TRAINED SPOTTER

            MINOR STREET FLOODING. HEAVY RAIN DURATION 1
            HOUR 10 MINUTES.

&&

EBW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
151 PM EDT TUE AUG 19 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0145 PM     HEAVY RAIN       2 W WAYLAND             42.67N 85.68W
08/19/2014  M0.98 INCH       ALLEGAN            MI   COCORAHS

            STILL RAINING MODERATELY AT OBSERVATION. NO
            FLOODING AT THIS TIME. HEAVY RAIN DURATION
            28 MINUTES.

&&

EBW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
252 PM EDT TUE AUG 19 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0228 PM     HEAVY RAIN       BYRON CENTER            42.81N 85.72W
08/19/2014  M2.10 INCH       KENT               MI   PUBLIC

            HEAVY RAIN DURATION 1 HOUR.

&&

EBW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
310 PM EDT TUE AUG 19 2014

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0247 PM     HEAVY RAIN       1 NNW MIDDLEVILLE       42.73N 85.48W
08/19/2014  M2.50 INCH       BARRY              MI   PUBLIC

            HEAVY RAIN DURATION 45 MINUTES.

&&

EBW