Special Weather Statement, NWS Twin Cities, MN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1142 PM CDT FRI JUN 19 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CDT FRI JUN 19 2015

EVERYTHING STILL LOOKS ON TRACK TO SEE A BOWING MCS MOVE ACROSS THE
AREA TONIGHT. WHERE THERE IS MORE UNCERTAINTY IS WHAT HAPPENS OUT
AHEAD OF THIS SYSTEM IN SRLY FLOW AND WAA. THIS HAS RESULTED IN AN
IMPRESSIVE LINE OF THUNDERSTORMS OVER CENTRAL SODAK. NONE OF THE
GUIDANCE REALLY PICKED UP ON THIS ALL THAT WELL...BUT BY 00Z...THE
HRRR AND A COUPLE OF THE HOPWRF MEMBERS SHOW SOME ACTIVITY IN WRN
MN. BASED ON WHERE ACTIVITY AND INSTABILITY ARE AT THE MOMENT...
THINK THIS IS TOO FAR EAST TO SEE ANYTHING THIS EVENING AND THINK
ANY OF THIS SORT OF ACTIVITY WOULD STAY TO OUR WEST/SW...BACK WHERE
THE INSTABILITY RESIDES.

FOR TONIGHT...THERE IS STRONG MODEL AGREEMENT IN THE CAMS ON AN
BOWING MCS DEVELOPING OVER SODAK. THIS MAKES PLENTY OF SENSE WHEN
LOOKING AT THE DETERMINISTIC MODELS...WHICH CONTINUE TO SHOW A SRLY
LLJ INCREASING TO AROUND 50 KTS BENEATH A WRLY 60 KT MID-LEVEL JET.
THE WAVE THAT WILL BE RESPONSIBLE FOR THIS SYSTEM IS CURRENTLY
MOVING ACROSS MT. STORMS SHOULD BEGIN TO BUILD IN ERN MONTANA
BETWEEN 3 AND 5 PM AND CONGEAL INTO A FORWARD PROPAGATING MCS
BETWEEN 7 AND 10 PM ALONG THE WRN NORTH/SOUTH DAKOTA BORDER. STORM
MOTION OFF THE HI-RES MODELS IS NEARLY 50 MPH...WHICH MATCHES UP
WELL WITH THE FORWARD PROPAGATING CORFIDI VECTORS OFF THE NAM. THIS
FORWARD MOTION IS WHAT WILL DRIVE THE HIGH WIND THREAT THIS
EVENING...BUT WILL ALSO DIMINISH PRECIPITATION TOTALS THAT WE SEE.
THOUGH PWATS UP NEAR 1.5 INCHES FAVOR A HEAVY RAIN THREAT...THE
FORWARD MOTION OF THE SYSTEM WILL REALLY CUT DOWN ON RAINFALL TOTALS
AND THINK ANY FLASH FLOOD THREAT WE HAVE TONIGHT WOULD COME WITHIN
THE COMMA HEAD OF A MATURE MCS IF ONE WERE TO DEVELOP.

AS FOR TIMING THIS SYSTEM IN THE GRIDS...GIVEN THE SPEED ITS
MOVING...FOLLOWED THE FASTER CAMS. THIS RESULTED IN SOMETHING CLOSE
TO WHAT THE HRRR HAS...SWITCHING TO THE HIRES-ARW ONCE WE GET PAST
THE 15 HOURS OF THE HRRR. ONE CONCERN FOR SEEING CONVECTION EARLIER
IS SOME OF THE CAMS ARE ALSO SHOWING A LEAD BAND OF WAA ELEVATED
CONVECTION DEVELOPING DIRECTLY AHEAD OF THE BOW. IF THIS WERE TO
OCCUR IT WOULD LEAD TO TWO THINGS...AN INCREASE IN THE SEVERE
THREAT...INCLUDING THE POSSIBILITY OF SOME BRIEF SPIN UPS. BESIDE
THAT...THIS WOULD HELP WITH THE HEAVY RAIN TREAT AS THE WAA BAND
WOULD RESULT IN A LEAD BAND OF HEAVY RAIN OUT AHEAD OF THE SQUALL
LINE...AND THIS WOULD ALSO BE THE SAME REGION WHERE COMMA HEAD
PRECIP WOULD BE MOST LIKELY.

FOR SATURDAY...THIS LINE WILL BE FALLING APART DURING THE MORNING
OVER WRN WI. BY THE AFTERNOON...NW WINDS WILL BE DEVELOPING WITH
DRIER AIR WORKING IN. LOOKING MORE AND MORE LIKELY THAT WE WILL NOT
SEE ANY ADDITIONAL PRECIP IN THE MPX CWA THE REST OF SATURDAY...WITH
AFTERNOON CONVECTION DEVELOPING FROM THE QUAD CITIES UP TOWARD GREEN
BAY. LEFT SOME CHANCE POPS IN DURING THE AFTERNOON FOR CONTINUITY...
BUT IF HI-RES MODELS CONTINUE TO SHOW A LACK OF STORMS SATURDAY
AFTERNOON IN THE MPX AREA...WE COULD PROBABLY JUST GO DRY FOR
SATURDAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CDT FRI JUN 19 2015

THE FIRST HALF OF THE LONGER TERM WILL FEATURE PERIODIC
PRECIPITATION EVENTS AS A SERIES OF SHORT WAVES PUSH THROUGH IN
THE STRONG BELT OF WESTERLY ACROSS THE NORTHERN TIER OF STATES.
THE POLAR FRONT WILL MEANDER BACK AND FORTH ACROSS OUR AREA
THROUGH EARLY NEXT WEEK RESULTING IN SMALL CHANCES FOR SHOWERS AND
THUNDERSTORMS. THE BEST AGREEMENT FOR PRECIPITATION EARLY ON
BETWEEN THE GFS AND ECMWF IS SUNDAY NIGHT INTO EARLY MONDAY AND
THEN AGAIN FROM LATE TUESDAY INTO WEDNESDAY. THE FRONTAL BOUNDARY
THEN BECOMES MORE STATIONARY BY MID WEEK FROM NEBRASKA THROUGH
NORTHERN ILLINOIS. IT/S THE MID WEEK PERIOD THAT IS TROUBLESOME
FOR HEAVY RAIN WITH THUNDERSTORM COMPLEXES EXPECTED TO MOVE ALONG
AND NORTH OF THIS BOUNDARY. A CHECK OF THE CIPS ANALOGS SHOWS THE
CHANCES FOR SIGNIFICANT RAIN AMOUNTS HIGHEST FROM NORTHERN IA
THROUGH NORTHERN IL...WHICH IS QUITE SIMILAR TO THE FORECAST FROM
THE 12Z ECMWF. HENCE...GRIDDED PRECIPITATION CHANCES ARE HIGHEST
ACROSS SOUTHERN MN THROUGH THE MID WEEK PERIOD. THE LATER HALF OF
NEXT WEEK INTO THE WEEKEND WILL FEATURE A BUILDING RIDGE IN THE
WEST WITH A DEEP TROUGH DEVELOPING ACROSS THE WESTERN GREAT LAKES.
THIS WILL LEAD TO MORE SHOWER CHANCES...ESPECIALLY FROM FRIDAY
ONWARD AS WELL AS SPREAD OUT MORE EVENLY ACROSS THE FA. LOW/HIGH
TEMPERATURES THROUGH NEXT FRIDAY (FIRST WEEK OF SUMMER) ARE
FORECAST TO BE QUITE CLOSE TO SEASONAL VALUES.

LOOKING AT THIS COMING SATURDAY NIGHT...THERE IS GOOD AGREEMENT IN
THE DETERMINISTIC MODELS THAT A COOL FRONT WILL BE PUSHING EAST OF
OUR WI COUNTIES IN THE EVENING. HENCE...ONLY A FEW SHOWERS ARE
EXPECTED IN THE EVENING ACROSS WEST CENTRAL WI WITH DRY WEATHER
ELSEWHERE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1135 PM CDT FRI JUN 19 2015

SHORT TERM MODELS CONTINUE TO ADVERTISE A LINE OF THUNDERSTORMS
FORMING ACROSS SD AND MOVING EAST RAPIDLY ACROSS WESTERN AND INTO
EASTERN MN BETWEEN 7-13Z. CURRENT REGIONAL RADAR DOES SUPPORT THIS
SCENARIO AS TWO AREAS OF TSRA ARE DEVELOPING/CONTINUING TO FORM
OVER CENTRAL SD...NE INTO SE ND. BASED ON THE SPEED OF THIS
LINE...WIND GUSTS WILL ACCOMPANY THIS TSRA LINE...BUT CONFIDENCE
IS LOW ON HOW WIDESPREAD 30-40 KT WINDS PROPAGATE EASTWARD. BEST
SCENARIO IS TO HOLD ONTO A 2-3 HR PERIOD OF SHRA AND EMBEDDED TSRA
STARTING AT KAXN/KRWF ARND 7-8Z...AND INTO KSTC BY 9-10Z. ALTHOUGH
CIGS WILL LOWER IN THE VCNTY OF THE TSRA...THE BIG FACTOR IS THE
VSBY WHICH IS LIKELY TO HOLD IN THE MVFR RANGE FOR 1-2 HRS...WITH
SMALL PERIODS OF IFR/LIFR VSBY IN HEAVY RAINFALL. WILL HOLD ONTO
THE 3SM TSRA...BUT CONFIDENCE IS HIGH FOR A SHORT PERIOD OF IFR
VSBY OR LOWER. BEHIND THE MAIN COMPLEX OF SHRA/TSRA...MVFR/IFR
CIGS WILL LIKELY DEVELOP SATURDAY MORNING...WITH A SLOW RISE
DURING THE AFTN BEFORE VFR SATURDAY EVENING.

KMSP...

CONFIDENCE IS HIGH THAT A LINE OF TSRA/SHRA WILL MOVE ACROSS THE
AIRFIELD BETWEEN 11-13Z. VCTS IS POSSIBLE AS EARLY AS 9Z WITH AN
ISOLD TSRA AHEAD OF THIS LINE. THERE IS ALSO HIGH CONFIDENCE OF A
PERIOD OF IFR/MVFR VSBY IN HEAVIER RAINFALL. THERE IS ALSO A
POSSIBILITY OF WIND GUSTS ALONG THIS LINE OF 40 KTS. BUT
CONFIDENCE IS TOO LOW FOR TIMING AND SPECIFICS. MVFR CIGS ARE ALSO
LIKELY BEHIND THE MAIN AREA OF SHRA/TSRA...AND WILL LIKELY LAST
UNTIL THE EARLY AFTN...WITH VFR CONDS SATURDAY EVENING. WINDS WILL
BE GENERALLY S/SE AHEAD OF THIS TSRA COMPLEX...WITH WINDS SHIFTING
TO THE WEST/NW BY THE AFTN.

/OUTLOOK FOR KMSP/

SUN...VFR WITH TSRA/SHRA POSSIBLE SUNDAY NIGHT. WINDS W AT 5-10 KT.
MON...VFR. WIND NW AT 5-10 KT.
TUE...VFR. CHC TSRA/SHRA. WINDS E AT 5-10 KT.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

SHORT TERM...MPG
LONG TERM...RAH
AVIATION...JLT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
624 PM CDT FRI JUN 19 2015

MNZ041>044-047>051-054>059-064>068-073>076-082-083-091-092-202330-
DOUGLAS-TODD-MORRISON-MILLE LACS-STEVENS-POPE-STEARNS-BENTON-
SHERBURNE-LAC QUI PARLE-SWIFT-CHIPPEWA-KANDIYOHI-MEEKER-WRIGHT-
YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-CARVER-REDWOOD-BROWN-
NICOLLET-LE SUEUR-WATONWAN-BLUE EARTH-MARTIN-FARIBAULT-
624 PM CDT FRI JUN 19 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
MINNESOTA...EAST CENTRAL MINNESOTA...SOUTH CENTRAL MINNESOTA...
SOUTHWEST MINNESOTA AND WEST CENTRAL MINNESOTA.

.DAY ONE...TONIGHT

A LINE OF THUNDERSTORMS WILL MOVE INTO WESTERN MINNESOTA AFTER
MIDNIGHT TONIGHT...AND RACE EASTWARD ACROSS SOUTHERN AND CENTRAL
MINNESOTA OVERNIGHT.

THERE WILL BE A RISK FOR DAMAGING WINDS AS THIS LINE MOVES ACROSS
MINNESOTA...PRIMARILY WEST OF THE INTERSTATE 35 CORRIDOR. TORRENTIAL
DOWNPOURS LEADING TO PONDING OF WATER ON ROADWAYS WILL ALSO BE OF
CONCERN...AS WELL AS THE POTENTIAL FOR A FEW OCCURRENCES OF LARGE
HAIL.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THUNDERSTORMS MAY REDEVELOP ON SATURDAY AFTERNOON...BUT THE
THREAT FOR SEVERE WEATHER IS LOW AT THIS TIME.

PERIODS OF THUNDERSTORMS ARE EXPECTED FROM SUNDAY AFTERNOON
THROUGH NEXT WEEK. AT THIS TIME THE THREAT FOR SEVERE STORMS
APPEARS LOW...ALTHOUGH HEAVY RAINFALL WILL BE OF CONCERN IN
LOCATIONS THAT RECEIVE REPEATED BOUTS OF THUNDERSTORM ACTIVITY.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION MAY BE NEEDED AFTER MIDNIGHT IN WESTERN
MINNESOTA.

MNZ045-052-053-060>063-069-070-077-078-084-085-093-WIZ014>016-
023>028-202330-
KANABEC-ISANTI-CHISAGO-HENNEPIN-ANOKA-RAMSEY-WASHINGTON-SCOTT-
DAKOTA-RICE-GOODHUE-WASECA-STEELE-FREEBORN-POLK-BARRON-RUSK-
ST. CROIX-PIERCE-DUNN-PEPIN-CHIPPEWA-EAU CLAIRE-
624 PM CDT FRI JUN 19 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL
MINNESOTA...SOUTH CENTRAL MINNESOTA...SOUTHEAST MINNESOTA...
NORTHWEST WISCONSIN AND WEST CENTRAL WISCONSIN.

.DAY ONE...TONIGHT

A LINE OF STRONG THUNDERSTORMS IS EXPECTED TO REACH THE
INTERSTATE 35 CORRIDOR AROUND DAYBREAK SATURDAY. THERE WILL BE A
RISK FOR DAMAGING WINDS. TORRENTIAL DOWNPOURS LEADING TO PONDING
OF WATER ON ROADWAYS WILL ALSO BE OF CONCERN.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THUNDERSTORMS MAY REDEVELOP SATURDAY AFTERNOON...BUT THE THREAT
FOR SEVERE WEATHER IS LOW AT THIS TIME.

PERIODS OF THUNDERSTORMS ARE EXPECTED FROM SUNDAY AFTERNOON
THROUGH NEXT WEEK. AT THIS TIME THE THREAT FOR SEVERE STORMS
APPEARS LOW...ALTHOUGH HEAVY RAINFALL WILL BE OF CONCERN IN
LOCATIONS THAT RECEIVE REPEATED BOUTS OF THUNDERSTORM ACTIVITY.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION IS NOT EXPECTED EAST OF INTERSTATE 35.

JLT

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1040 PM CDT FRI JUN 19 2015

MNZ082-091-200430-
WATONWAN-MARTIN-
1040 PM CDT FRI JUN 19 2015

...A STRONG THUNDERSTORM WILL AFFECT WESTERN MARTIN AND SOUTHWESTERN
WATONWAN COUNTIES...

AT 1039 PM CDT...A STRONG THUNDERSTORM WAS NEAR BERGEN...OR NEAR
WINDOM...MOVING EAST AT 40 MPH. THE STORM WILL CROSS INTO
SOUTHWESTERN WATONWAN AND WESTERN MARTIN COUNTIES BY 1055 PM.

WIND GUSTS UP TO 50 MPH AND DIME SIZE HAIL ARE POSSIBLE WITH THIS
STORM.

LOCATIONS IMPACTED INCLUDE...
FAIRMONT...SHERBURN...TRUMAN...TRIMONT...WELCOME...ORMSBY...ODIN...
FOXLAKE AND WILBERT.

THIS INCLUDES INTERSTATE 90 BETWEEN MILE MARKERS 82 AND 100.

LAT...LON 4359 9485 4390 9486 4391 9485 4386 9439
      4355 9453
TIME...MOT...LOC 0339Z 285DEG 33KT 4382 9506

AJZ

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
406 AM CDT SAT JUN 20 2015

MNZ054-064-200930-
YELLOW MEDICINE-LAC QUI PARLE-
406 AM CDT SAT JUN 20 2015

...A STRONG THUNDERSTORM WILL AFFECT YELLOW MEDICINE AND LAC QUI
PARLE COUNTIES...

AT 406 AM CDT...A STRONG THUNDERSTORM WAS OVER BOYD...OR 10 MILES
SOUTHWEST OF MONTEVIDEO...MOVING NORTHEAST AT 45 MPH.

WIND GUSTS OF 50 TO 55 MPH ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
GRANITE FALLS...CANBY...MADISON...DAWSON...CLARKFIELD...HANLEY
FALLS...PORTER...BOYD...BELLINGHAM...MARIETTA...CERRO GORDO AND
PROVIDENCE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 600 AM CDT FOR
WEST CENTRAL MINNESOTA.

LAT...LON 4527 9645 4525 9629 4522 9627 4516 9605
      4500 9583 4496 9582 4493 9573 4491 9572
      4491 9568 4484 9557 4479 9550 4478 9553
      4476 9549 4463 9574 4463 9645
TIME...MOT...LOC 0906Z 225DEG 40KT 4488 9592

JRB