Flooding in Michigan, April 28 to 30, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
732 PM EDT SAT APR 27 2013

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 413 PM EDT SAT APR 27 2013

UPPER AIR PATTERN CONSISTS OF A 500 MB LOW AND TROUGH OVER THE
CENTRAL PLAINS WITH A ZONAL FLOW ACROSS THE NORTHERN U.S. THIS
MORNING. A SHORTWAVE TROUGH THEN MOVES INTO THE NORTHERN PLAINS SUN
AFTERNOON. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE MOVING
INTO THE WESTERN CWA SUN AFTERNOON ALONG WITH SOME DEEPER MOISTURE.

PRETTY QUIET FORECAST FOR THIS TIME PERIOD WITH A CHANCE OF PCPN
COMING IN LATE SUN AFTERNOON ACROSS WESTERN UPPER MICHIGAN. ONE
THING I DID ADD TO THE FORECAST TONIGHT WAS SOME PATCHY FOG AFTER
MIDNIGHT IN CASE SNOW MELT MOISTURE AND LIGHT WINDS CAUSE IT TO
FORM. DO NOT THINK THE FOG IF IT DOES FORM WILL GET TOO OUT OF HAND.
OTHERWISE...DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR
TEMPERATURES OR WEATHER.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 413 PM EDT SAT APR 27 2013

ZONAL PATTERN ALOFT TO START LONG TERM. SHORTWAVE TROUGH MOVING
ACROSS NORTHERN MANITOBA AND ONTARIO KEEPS MAJORITY OF WIDESPREAD
ORGANIZED PRECIP AWAY FROM UPR LAKES. SMALLER SHORTWAVE AND UPPER
JET ALONG WITH SFC TROUGH COMBINE WITH INCREASING MOISTURE /H85
DWPNTS UP TO AROUND +6C AND PWATS 200 PCT OF NORMAL/ TO PRODUCE
BAND OF SHOWERS ALONG AND BEHIND THE TROUGH SUNDAY NIGHT. GFS
REMAINS QUICKER THAN ECMWF/NAM/WPC HAND DRAWN PROGS WITH FRONT BY
12Z ON MONDAY. RIDGING ALOFT DOWNSTREAM SUPPORTS SLOWER ARRIVAL TO
THE RAIN. MID-LEVEL LAPSE RATES TO 7C/KM INDICATE CONVECTIVE
ELEMENTS POSSIBLE TO RAINFALL. SREF PROBABILITES OF QPF SHOW
DECENT CHANCE OF SEEING OVER 0.25 INCH OVR WESTERN AND SOUTHWEST
CWA...BUT JUST A MARGINAL CHANCE OF SEEING OVER ONE-HALF INCH OF
QPF. MOST OF THE RAINFALL WOULD AFFECT RIVER BASINS OF WESTERN CWA.
FRONT SLIDES THROUGH CWA ON MONDAY THEN STRONGER SHORTWAVE TROUGH
AND SFC LOW HEADS INTO THE NORTHERN PLAINS MONDAY NIGHT. COOLING
BEHIND TROUGH ON MONDAY MOST NOTICABLE IN NORTHERN CWA NEAR LK
SUPERIOR WITH GRADIENT NORTH WINDS ENHANCED BY LAKE BREEZE. FARTHER
INLAND AND EXTENDING TO LK MICHIGAN SHORE...TEMPS SHOULD TOP OUT IN
THE 60S.

NEXT CHANCES OF PRECIP MORE UNCERTAIN MONDAY NIGHT INTO TUESDAY
AND TUESDAY NIGHT. FRONT THAT MOVES THROUGH ON MONDAY COULD SERVE
AS FOCUS FOR DEVELOPING LOW PRESSURE WAVE/MORE PRECIP MONDAY NIGHT
INTO TUESDAY. GEM-NH SLOWS FRONT UP ENOUGH TO HAVE ADDITIONAL PRECIP
OVER ROUGHLY EAST HALF OF CWA MONDAY EVENING. OTHER MODELS AND WPC
HAND DRAWN PROGS PUSH FRONT THROUGH CWA BY THAT TIME. MAY ALSO SEE
FOCUS FOR PRECIP SET UP MAINLY TO SOUTH OF UPR MICHIGAN INTO TUESDAY
CLOSER TO HIGHER BLYR DWPNTS NEAR DEVELOPING WARM FRONT. MODELS DO
SEEM TO AGREE MORE THAN ANOTHER AREA OF ENHANCED PRECIP WILL BE
MAINLY NORTH AND WEST OF LK SUPERIOR REGION ALONG FRONT EDGE OF
SHARPENING LARGER SCALE TROUGHING FROM WESTERN CANADA INTO
NORTHERN PLAINS. ASSOCIATED SFC LOW WOULD MAKE RUN INTO UPR
LAKES BEFORE BEING DEFLECTED INTO ONTARIO NORTH OF LK SUPERIOR.
OUT AHEAD OF THE LOW...SEEMS THAT COLD FRONT WILL PUSH ACROSS
UPR MICHIGAN TUESDAY AFTN AND TUESDAY EVENING. SHOULD BE AT LEAST
SCT-BKN MID CLOUDS ON TUESDAY...POSSIBLY MORE CLOUDS IF STRONGER
WARM FRONT DOES DEVELOP TO THE SOUTH. GIVEN H85 TEMPS OVER +12C
THOUGH SHOULD STILL SEE MAX TEMPS PUSHING PAST 70 DEGREES IN MANY
AREAS OF THE WEST.

MODELS TYPICALLY OVERDONE WITH DWPNTS EARLY IN THE WARM SEASON...BUT
EVEN HERE ECMWF SHOWS DWPNTS INTO THE 50S AND EVEN NEAR 60F IN THE
SOUTH. RESULT IS SFC BASED INSTABILITY INCREASING WITH MUCAPE OVR
MOST CWA 400-800 J/KG AND MAYBE EVEN AS HIGH AS 1000J/KG IN THE
SOUTH. SOME TSRA SEEM GOOD BET WITH THIS PATTERN AND PROJECTED
MOISTURE/INSTABILITY. SINCE STRONGER WINDS AT H7/H5/H3 ARE WELL TO
NORTHWEST...REDUCING DEEP LAYER SHEAR...PRETTY SMALL POTENTIAL FOR
ANY SVR STORMS. HOWEVER...H85 DWPNTS OVER 10C AND SFC FRONT RUNNING
PARALLEL TO UPPER HEIGHTS COULD RESULT IN HEAVY DOWNPOURS IN THE
CONVECTIVE ELEMENTS. WILL HAVE TO FOCUS ON THIS IN THE NEXT COUPLE
DAYS GIVEN THE ONGOING SNOWMELT AND RISING RIVER LEVELS THAT WILL
ALSO BE OCCURRING DURING THIS TIME.

EXTENDED...SFC FRONT SHOULD PUSH EAST OF UPR LAKES BUT THIS DOES
NOT MEAN THERE ARE ONLY LIMITED CHANCES OF PRECIPITATION. APPEARS
THAT UPR LAKES WILL BE WITHIN INFLUENCE OF PERSISTENT H85
TROUGH/MOISTURE RIBBON EVEN IN WAKE OF THE SFC FRONTAL PASSAGE LATER
TUESDAY NIGHT. SETUP PERSISTS THROUGH END OF THE WEEK. MULTIPLE
EPISODES OF PRECIP POSSIBLE AS UPR LAKES WILL BE ON EDGE OF BROAD
UPR JET/DIVERGENCE AREA ON LEADING EDG E OF SLOWLY MOVING TROUGH
ALOFT. POTENTIAL THAT TROUGH ALOFT SLOWS UP/STALLS AS ANOTHER RIDGE
ALOFT BUILDS FARTHER DOWNSTREAM OVR NEW ENGLAND AND EASTERN CANADA.
PATTERN GETS FURTHER MUDDLED BY LATE WEEK AS UPPER TROUGH/CLOSED LOW
STILL LOOKS TO FORM SOMEWHERE IN THE CNTRL CONUS. OVERALL THERE IS
LOW CONFIDENCE ON DETAILS OF THE PATTERN BUT AT THE LEAST TEMPS WILL
COOL COMPARED TO THE WARMTH EXPERIENCED EARLY THIS WEEK...AND IT
COULD BE COLD ENOUGH TO INCLUDE AT LEAST A MIX OF RAIN AND SNOW FOR
THE WESTERN TIER BY LATE IN THE WEEK.
&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 731 PM EDT SAT APR 27 2013

EXPECT VFR CONDITIONS TO PREVAIL THIS TAF PERIOD WITH RELATIVELY DRY
AIRMASS DOMINATING IN SW FLOW ARND HI PRES OVER NEW ENGLAND. NOT OUT
OF THE QUESTION THERE COULD BE SOME FOG...MAINLY AT SAW WHERE SFC
DEWPTS ARE HIER...BUT LEFT OUT OF THE FCST FOR NOW. AS THE PRES
GRADIENT TIGHTENS BTWN THIS HI AND FALLING MSLP IN THE PLAINS...
EXPECT SOME LLWS TO DVLP AT CMX/IWD OVERNGT. THE ONSET OF DAYTIME
HEATING BY MID/LATE SUN MRNG WL MIX OUT THE HIER WINDS AND ALLOW
GUSTY SW WINDS TO REACH THE SFC.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 413 PM EDT SAT APR 27 2013

WINDS SHOULD STAY BELOW 25KTS THROUGH THE PERIOD WITH NO GALES IN
SIGHT. NO STRONG SYSTEMS WILL BE COMING CLOSE TO THE AREA...SO NO
STRONG PRESSURE GRADIENTS ARE EXPECTED.
&&

.HYDROLOGY...
ISSUED AT 413 PM EDT SAT APR 27 2013

WARM TEMPERATURES WILL RESULT IN A PERSISTENT SNOW MELT INTO THE
UPCOMING WEEK. THE PEAK OF THE WARMING WILL OCCUR THROUGH TUESDAY
WITH COOLER TEMPERATURES MID TO LATE WEEK. DAYTIME HIGHS FOR MANY
AREAS THROUGH TUESDAY WILL BE IN THE 60S AND 70S WHILE NIGHTTIME
LOWS ARE IN THE 40S. INCREASING MOISTURE AND WARMING TEMPERATURES
WILL MAKE THE SNOW PACK EVEN MORE PRIMED FOR RAPID MELTING THE
REST OF THE WEEKEND. SINCE SOILS ARE QUITE SATURATED...MUCH OF
THIS MELTING SNOW WILL GO TO RUN OFF. ADDITIONAL PRECIP IS EXPECTED
SUNDAY NIGHT AND MONDAY. AT THIS POINT MODEL PROBABILITES OF
QPF SHOW DECENT CHANCE OF SEEING OVER 0.25 INCH OVR WESTERN AND
SOUTHWEST CWA...BUT JUST A MARGINAL CHANCE OF SEEING OVER ONE-HALF
INCH OF QPF. FURTHER CHANCES OF PRECIPITATION ARE EXPECTED AS COLD
FRONT WORKS THROUGH ON TUESDAY...WHEN THERE MAY BE THUNDERSTORMS
TOO. OTHERWISE...ADDITIONAL CHANCES OF PRECIPITATION ARE POSSIBLE
THE REST OF THE WEEK AS FRONT STAYS CLOSE BY TO THE AREA.

RIVER LEVELS ARE BEGINNING TO RISE AND WILL CONTINUE TO DO SO
THROUGH THE UPCOMING WEEK. BASED ON EXISTING SNOW WATER
EQUIVALENT...THE MOST SIGNIFICANT ISSUES ARE EXPECTED OVER THE
WESTERN HALF OF UPPER MICHIGAN. AFTER THE LATEST ROUND OF SURVEYS
AND READINGS TODAY ALONG WITH THE LATEST GUIDANCE FROM THE RIVER
FORECAST CENTER...RIVER FLOOD WATCHES HAVE BEEN ISSUED ALONG THE
STURGEON RIVER NEAR ALSTON AND CHASSELL...AND ON THE PESHEKEE RIVER
NEAR CHAMPION. MELTING SCENARIOS REMAIN THE BIGGEST CONFIDENCE
REDUCERS AT THIS POINT...AND IF THE RIVER FORECAST CENTER HAS TO
INCREASE THE MELT FACTOR CORRECTION GOING INTO THE RIVER MODELS THE
FORECASTS WILL LIKELY END UP QUITE A BIT HIGHER. OF COURSE...MAIN
STEM RIVERS ARE NOT THE ONLY HAZARD...AS WE ARE ALSO LOOKING AT
THREAT OF AREAL FLOOD PROBLEMS WITH SMALLER CREEKS/STREAMS AND
STANDING WATER ON ROADS. FOR FURTHER DETAILS...SEE THE HYDROLOGIC
OUTLOOK /ESF/ AND THE LATEST RIVER WATCHES /FFAMQT/.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...07
LONG TERM...JLA
AVIATION...KC
MARINE...07
HYDROLOGY...JLA

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MARQUETTE MI
432 PM EDT SAT APR 27 2013

MIZ001>007-009>014-084-085-281200-
KEWEENAW-ONTONAGON-NORTHERN HOUGHTON-BARAGA-MARQUETTE-ALGER-LUCE-
GOGEBIC-IRON-DICKINSON-MENOMINEE-DELTA-SOUTHERN SCHOOLCRAFT-
SOUTHERN HOUGHTON-NORTHERN SCHOOLCRAFT-
432 PM EDT SAT APR 27 2013 /332 PM CDT SAT APR 27 2013/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN UPPER
MICHIGAN AND CENTRAL UPPER MICHIGAN.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ABOVE NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK WILL INCREASE SNOW
MELT...RESULTING IN RISING RIVER LEVELS AND SOME FLOODING ACROSS
UPPER MICHIGAN. SEE THE LATEST HYDROLOGIC OUTLOOK...RIVER FLOOD
STATEMENTS...AND FORECASTS FOR FURTHER DETAILS.

THUNDERSTORMS ARE POSSIBLE TUESDAY AND TUESDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO SUBMIT REPORTS TO THE NATIONAL
WEATHER SERVICE IN MARQUETTE. THE PUBLIC MAY ALSO SUBMIT REPORTS AT
OUR WEBPAGE...FACEBOOK PAGE OR ON TWITTER.

LSZ162-240>251-263>267-281200-
LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRAND
PORTAGE MN BEYOND 5NM-SAXON HARBOR WI TO BLACK RIVER MI-
BLACK RIVER TO ONTONAGON MI-
ONTONAGON TO UPPER ENTRANCE OF PORTAGE CANAL MI-
UPPER ENTRANCE OF PORTAGE CANAL TO EAGLE RIVER MI-
EAGLE RIVER TO MANITOU ISLAND MI-
MANITOU ISLAND TO POINT ISABELLE MI-
POINT ISABELLE TO LOWER ENTRANCE OF PORTAGE CANAL MI-
LOWER ENTRANCE OF PORTAGE CANAL TO HURON ISLANDS MI INCLUDING
KEWEENAW AND HURON BAYS-HURON ISLANDS TO MARQUETTE MI-
MARQUETTE TO MUNISING MI-MUNISING TO GRAND MARAIS MI-
GRAND MARAIS TO WHITEFISH POINT MI-
LAKE SUPERIOR FROM SAXON HARBOR WI TO UPPER ENTRANCE TO PORTAGE
CANAL MI 5NM OFF SHORE TO THE US/CANADIAN BORDER INCLUDING ISLE
ROYALE NATIONAL PARK-
LAKE SUPERIOR FROM UPPER ENTRANCE TO PORTAGE CANAL TO MANITOU
ISLAND MI 5NM OFF SHORE TO THE US/CANADIAN BORDER-
LAKE SUPERIOR WEST OF LINE FROM MANITOU ISLAND TO MARQUETTE MI
BEYOND 5NM FROM SHORE-
LAKE SUPERIOR EAST OF A LINE FROM MANITOU ISLAND TO MARQUETTE MI
AND WEST OF A LINE FROM GRAND MARAIS MI TO THE US/CANADIAN BORDER
BEYOND 5NM FROM SHORE-
LAKE SUPERIOR FROM GRAND MARAIS MI TO WHITEFISH POINT MI 5NM OFF
SHORE TO THE US/CANADIAN BORDER-
432 PM EDT SAT APR 27 2013 /332 PM CDT SAT APR 27 2013/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN LAKE
SUPERIOR...CENTRAL LAKE SUPERIOR AND WESTERN LAKE SUPERIOR.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS TUESDAY AND TUESDAY NIGHT
MAINLY OVER EASTERN SECTIONS OF LAKE SUPERIOR.

.SPOTTER INFORMATION STATEMENT...

THE NEED FOR WEATHER SPOTTER REPORTS IS NOT ANTICIPATED AT THIS
TIME.

LMZ221-248-250-281200-
GREEN BAY NORTH OF LINE FROM CEDAR RIVER MI TO ROCK ISLAND
PASSAGE-SEUL CHOIX POINT TO POINT DETOUR MI-
5NM EAST OF A LINE FROM FAIRPORT MI TO ROCK ISLAND PASSAGE-
432 PM EDT SAT APR 27 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN LAKE
MICHIGAN.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS TUESDAY AND TUESDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

THE NEED FOR WEATHER SPOTTER REPORTS IS NOT ANTICIPATED AT THIS
TIME.

JLA