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000
FXUS63 KDLH 191809
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
109 PM CDT SUN MAY 19 2013

.AVIATION...18Z TAFS

A WIDE RANGE OF CONDITIONS WERE OCCURRING ACROSS THE NORTHLAND SO
FAR TODAY...WITH IFR OVER MUCH OF FAR NORTHERN MINNESOTA...AND VFR
SOUTH. CU WAS EXPANDING AND MOVING NORTH THROUGH MINNESOTA...AND
SHOULD PROVIDE MVFR CEILINGS TO KBRD. THESE CEILINGS SHOULD RISE AS THE
AFTERNOON PROGRESSES. THE IFR CEILINGS OVER FAR NORTHERN MINNESOTA
MAY ALSO LIFT FROM SOUTH TO NORTH...BUT THE LATEST RAP SUGGESTS
KINL WILL REMAIN IFR.

AREAS AROUND LAKE SUPERIOR WILL BE ANOTHER CHALLENGE WITH A MOIST
FLOW OFF OF THE LAKE. VSBYS HAVE RISEN AT MOST AREAS AROUND THE
LAKE...BUT THE MOIST FLOW MAY ALLOW VSBYS TO DROP AGAIN AT TIMES.
THIS AREA WILL BE A MAJOR CHALLENGE INTO THIS EVENING...THEN WE
EXPECT VSBYS/CEILINGS TO LOWER AGAIN.

RAIN WAS FALLING OVER PORTIONS OF NORTHERN MINNESOTA AS OF EARLY
AFTERNOON...AND WE EXPECT SHOWERS/STORMS TO EXPAND IN COVERAGE
LATER THIS AFTERNOON INTO TONIGHT. SOME OF THE STORMS COULD BE
QUITE STRONG...ESPECIALLY OVER THE SOUTHERN HALF OF THE NORTHLAND.

&&

.PREV DISCUSSION... /ISSUED 1101 AM CDT SUN MAY 19 2013/

UPDATE...
INCREASED POPS/QPF AMOUNTS THIS MORNING FOR NRN TIER OF COUNTIES
TODAY WHERE A REGION OF STRONG H92 MB FGEN AND H50 OMEGA HAS
ALLOWED FOR SHRA/TSTM TO CONTINUOUSLY REGENERATE AND TRAIN OVER
THE REGION. AS OF 1100 AM...AUTOMATED WEATHER STATIONS ALONG THE
BORDERLAND FROM INTL FALLS TO CRANE LAKE HAD REPORTED AROUND AN
INCH OF RAINFALL SINCE 600 AM. A FLOOD WATCH CONTINUES FOR ALL OF
THE NE MN ZONES THROUGH MONDAY EVENING.

ALLOWED THE DENSE FOG ADVISORY TO EXPIRE. HOWEVER...AREAS OF LIGHT
FOG WITH VISIBILITY OF A MILE OR LESS WILL CONTINUE TO BE FOUND
NEAR LAKE SUPERIOR THROUGH THE DAY/TONIGHT. LOCALIZED DENSE FOG WILL
PERSIST ALONG THE HIGHER TERRAIN NEAR LAKE SUPERIOR...INCLUDING
ALONG THE PATTISON RIDGE SOUTH OF SUPERIOR...ALONG THE THOMPSON
HILL IN PROCTOR...AND ALONG THE MILLER HILL IN HERMANTOWN.

PREV DISCUSSION... /ISSUED 401 AM CDT SUN MAY 19 2013/

FLASH FLOOD WATCH ISSUED FOR NORTHEAST MINNESOTA THROUGH MONDAY...

SHORT TERM...AREA OF 85H FRONTOGENESIS ACROSS NR MN CWA
CONTINUES TO PRODUCE SCTD CONVECTION ALTHOUGH AREAL COVERAGE HAS
DECREASED OVER LAST FEW HRS. MEANWHILE LARGE AREA OF RAIN AND
THUNDERSTORMS STRETCHES FROM SERN NODAK INTO SWRN MN/NWRN IOWA.
THIS IS ASSOCIATED WITH PWS AXIS AND EJECTING MID LVL SHORTWAVE
TROF. DENSE FOG STILL LINGERS NEAR LAKE SUPERIOR AND SHOULD
CONTINUE INTO MID MORNING...IF NOT LONGER.

TODAY/TONIGHT/TOMORROW...ANOMALOUS UPPER TROF OVER CTRL CONUS WILL
CONTINUE TO ADVECT PWATS IN EXCESS OF 1.5 INCHES INTO THE REGION
NEXT 48 HRS. MAIN FOCUS AT LOW LEVELS WILL BE INVERTED TROUGH
ORIGINATING FROM SFC LOW ACROSS ERN SODAK INTO NWRN MN THIS AFTN.
HAVE EXPANDED THE FFA TO INCLUDE ALL MN ZONES THROUGH MONDAY. VERY
SLOW MOVING NATURE OF SFC/MID LVL LOW...VERY HIGH PWS..AND DEEP
CYCLONIC NATURE OF UPPER FLOW WILL ENSURE A PROLONGED PERIOD OF
WET WEATHER ACROSS THE CWA. DIFFICULT TO ASCERTAIN TIMING OF
PRECIPITATION AREAS BUT WITH WARM CLOUD DEPTHS NEAR/ABOVE 3KM ANY
CONVECTION WILL HAVE ACCESS TO VERY WET PROFILES INTO MONDAY.
CONFIDENCE IS LOW/MEDIUM ON FLOOD POTENTIAL. FFG VALUES ARE
STARTING LOWEST OVER SWRN CWA HOWEVER REMAINDER OF CWA COULD
EXPERIENCE ISSUES WITH TIME DUE TO PROLONGED NATURE OF QPF
POTENTIAL. AT LOW LVLS...SFC HIGH OVER CANADA WILL SUPPLY
INCREASINGLY STRONG LOW LVL EAST/NORTHEAST FLOW INTO MN THIS
EVENING INTO MONDAY. ALTHOUGH LOW LEVEL DRY AIR WILL TRY TO MAKE
ITS AWAY INTO NERN MN...CURRENT IDEA IS THAT ANY COLD DOME
ESTABLISHED FROM LAKE WILL BE TOPPED BY ADVECTION OF WARM AND
SOMEWHAT UNSTABLE AIR ALOFT. MAY NEED TO EXTEND FFA INTO WISC
ZONES WITH AFTERNOON FORECAST UPDATES.

LONG TERM...MONDAY NIGHT THROUGH SUNDAY.

THE MASSIVE CLOSED LOW PRESSURE SYSTEM THAT WILL COVER MUCH OF THE
CENTRAL UNITED STATES EARLY IN THE PERIOD WILL CONTINUE TO AFFECT
THE WEATHER ACROSS THE NORTHLAND FOR THE FIRST PART OF THE EXTENDED.
THE CLOSED LOW WILL BE IN SOUTH DAKOTA MONDAY NIGHT...AND MOVE
TOWARD THE IOWA/MN/SD BORDER BY 00Z WED. THE LOW WILL BEGIN TO OPEN
UP AFTER THAT...MOVING INTO SOUTHERN WISCONSIN BY 00Z THURSDAY.
SHOWERS AND THUNDERSTORMS WILL BE LIKELY FOR MUCH OF THE REGION
MONDAY NIGHT INTO WEDNESDAY...AND THEN THE SHOWERS AND THUNDERSTORMS
WILL BEGIN TO SAG TO THE SOUTH AND EAST. DRY HIGH PRESSURE WILL DRY
OUT THE NORTH ON WEDNESDAY AND WEDNESDAY NIGHT...AND ESPECIALLY ON
THURSDAY. THURSDAY THROUGH FRIDAY NIGHT SHOULD GENERALLY BE DRY AND
QUIET ACROSS THE NORTHLAND...AS HIGH PRESSURE BUILDS IN. THE NEXT
BATCH OF PRECIPITATION WILL BE POSSIBLE SATURDAY INTO SUNDAY...
ALTHOUGH THE MODELS ARE SHOWING SOME DECENT TIMING ISSUES AND
DIFFERENCES IN SURFACE LOW AND UPPER LEVEL PATTERNS. TEMPERATURES
THROUGHOUT THE EXTENDED SHOULD LARGELY BE IN THE 60S...WITH SOME
SPOTTY 70S AT TIMES...AND 40S AND 50S AT TIMES NEAR THE LAKE.

UPDATE...RETRANSMITTED NEW ZFP AFTER UPDATE OF GRIDS. POPS
MINIMAL THROUGH 12Z. TWO AREAS OF PRECIP WILL BE ACROSS NRN MN CWA
IN AREA OF 85H FRONTOGENESIS...AND OVER SWRN CORNER CLOSER TO AREA
OF INSTABILITY AND APPROACHING MCS. FFA STILL IN PLACE FOR
PROSPECT OF ANOTHER DOSE OF RAIN BETWEEN 12Z-18Z.

&&

.POINT TEMPS/POPS...
DLH  43  49  43  51 /  90  90  70  70
INL  51  56  45  61 /  80  80  70  60
BRD  54  67  49  60 /  80  80  70  70
HYR  59  73  52  64 /  80  90  70  70
ASX  51  62  45  53 /  90  90  70  70

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH THROUGH MONDAY EVENING FOR MNZ010>012-018>021-
     025-026-033>038.

WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 5 AM CDT TUESDAY FOR LSZ121-140>148.

&&

$$

SHORT TERM...GRANING
AVIATION...MELDE