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000
FXUS63 KDLH 211853
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
153 PM CDT MON JUL 21 2014

.UPDATE...
ISSUED AT 153 PM CDT MON JUL 21 2014

HAVE UPDATED TO EXPAND/EXTEND THE HEAT ADVISORY A LITTLE...AS THE
TWIN PORTS ARE GETTING SOME HEAT INDEX VALUES IN THE 95-100 RANGE
ALREADY...AND WE HAVE A FEW MORE DEGREES OF HEATING WITH DEWPOINTS
SITTING IN THE LOW 70S. SINCE THIS IS SO UNCOMMON HERE...AND SO
FEW HOMES HAVE AIR CONDITIONING...HAVE DECIDED TO EXPAND THE
ADVISORY INTO THE TWIN PORTS. ALSO... TEMPERATURES ARE LINGERING
INTO THE EVENING A BIT MORE WITH THE LATEST UPDATE...SO HAVE
EXTENDED TO 8PM AS WELL.

UPDATE ISSUED AT 1234 PM CDT MON JUL 21 2014

UPDATED FOR THE 18Z AVIATION DISCUSSION BELOW.

UPDATE ISSUED AT 711 AM CDT MON JUL 21 2014

ADDED A MENTION OF SCATTERED SHOWERS AND STORMS TO SOUTHERN CASS
AND CROW WING COUNTIES THIS MORNING. THIS IS DUE TO QUICKLY
DEVELOPING CELLS OVER THIS AREA AND EXTENDING WWD INTO SE ND.
REST OF THE FORECAST ON TRACK.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 318 AM CDT MON JUL 21 2014

SHORT TERM FOCUS IS ON HEADLINES AND POTENTIAL MCS TONIGHT. SFC
PRESSURE ANALYSIS AT 07Z FOUND SFC RIDGING BUILDING NWD THROUGH THE
FA ON A SLY FLOW. AN OUTFLOW BOUNDARY FROM STORMS IN ONTARIO WAS
KNIFING THROUGH THE FA AND LOCATED NEAR GPZ TO ELO AND THE CANADIAN
BORDER. AS THIS OUTFLOW ENCOUNTERS THE H7 CAP OF 10C...ONLY SOME
CLOUDS WERE FORMING ALONG THE BOUNDARY. HAVE REMOVED THE POPS
THROUGH 12Z. MAINTAINED THE PRIOR FORECAST OF NO POPS THROUGH 18Z
TODAY. A WSW FLOW ALOFT AND A SLY LOW LEVEL FLOW WILL PERSIST
THROUGH THE DAY. A HOT AND HUMID AIRMASS ON THE SLY FLOW WILL RESULT
IN MAX TEMPS IN THE MIDDLE TO UPPER 80S...WITH SOME ISOLD TEMPS
AROUND 90. 70S ALONG THE N SHORE OF LAKE SUPERIOR. SFC DEWPOINTS ARE
STILL FORECAST TO REACH INTO THE UPPER 60S ALONG THE CANADIAN BORDER
TO THE LOWER TO MIDDLE 70S ALONG THE SOUTHERN EDGE OF THE FA. HEAT
INDICES WILL REACH INTO THE 80S AND 90S. HEAT ADVISORY CRITERIA WILL
BE MET OVER THE SW QUAD OF THE FA INTO PINE AND BURNETT
COUNTIES...BUT NOT UNTIL 18Z WITH SOME IMPROVEMENT BY 00Z/22. AS A
RESULT HAVE ADJUSTED THE BEGIN AND END TIMES FOR THE ADVISORY
ACCORDINGLY AND REMOVED SOME COUNTIES FROM THE ADVISORY.

ADJUSTMENTS WERE ALSO MADE TO THE POPS FOR THIS AFTERNOON. LATEST
MODEL GUIDANCE SUGGESTS THAT THE THUNDERSTORMS WILL HOLD OFF UNTIL
AFTER 21Z. THIS IS WHEN SHORT WAVE ENERGY REACHES EASTERN ND AND
BEGINS TO DEVELOP STORMS. HOWEVER...H7 CAP TEMPS OF 10-14C WILL
COVER THE FA AND PRECLUDE STORMS FROM REACHING THE WESTERN FA. ONLY
HAVE SMALL POPS THROUGH 23Z.

MODELS ARE CONSISTENT WITH THE FORMATION OF AN MCS OVER EASTERN ND
AND WESTERN MN ABOUT 00Z AND MOVING OVER THE FA THROUGH 12Z.
DAMAGING WINDS AND HEAVY RAIN WILL BE THE MAIN THREATS. WITH THE HOT
AIRMASS TO BE OVERCOME...NOT EXPECTING HAIL. FOR SEVERE DETAILS
CHECK THE SPC DAY 1 OUTLOOK. HAVE ATTEMPTED TO ALIGN THE HIGHEST
POPS TO ACCOMPANY THE MCS AS IT CROSSES AND TO MATCH THE NEIGHBOR
OFFICES.

ON TUESDAY...THE MCS WILL CONTINUE TO MARCH OUT OVER LAKE SUPERIOR
IN THE MORNING AND HAVE POPS DIMINISHING IN THE MORNING FROM W TO E.
BY TUESDAY AFTERNOON...THE MCS WILL HAVE EXITED THE AREA COMPLETELY
WITH HIGH PRESSURE BUILDING IN BEHIND. LINGERED A POP OVER PRICE
COUNTY IN THE AFTERNOON FOR ANY BACKWASH LEFTOVER.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 AM CDT MON JUL 21 2014

THE UPPER LEVEL RIDGE WILL BUILD OVER THE HIGH PLAINS WHILE SFC HIGH
RESIDES OVER THE UPPER GREAT LAKES FOR MIDWEEK. THIS WILL GIVE THE
NORTHLAND SEASONAL TEMPERATURES AND DRIER WEATHER. THE RIDGE WILL
BREAK DOWN LATE IN THE WEEK AS AN UPPER LEVEL LOW MAKES LANDFALL INT
HE PACIFIC NORTHWEST AND DIGS INTO THE RIDGE. IN RESPONSE...LOW
PRESSURE WILL DEVELOP OVER THE HIGH PLAINS. THE LOW WILL BRING A
COLD FRONT THROUGH THE NORTHLAND ON SATURDAY...BUT RETURN FLOW AHEAD
OF THE SYSTEM COULD CAUSE SOME SHOWERS AND THUNDERSTORMS AS EARLY AS
FRIDAY...MAINLY IN WESTERN AREAS OF THE FORECAST AREA.  THE THREAT
OF SHOWERS AND STORMS WILL THEN PERSIST THROUGH THE WEEKEND AS THE
SYSTEM MOVES THROUGH. THE GFS IS MUCH STRONGER WITH THIS LOW AND
EVEN CLOSES IT OFF OVER NRN MN ON SUNDAY...WHILE THE ECMWF KEEPS IT
OPEN UNTIL LATER IN THE WEEK...CLOSES IT THEN HAS IT RETROGRADING
INTO THE GREAT LAKES.  AS EXPECTED THE GFS PRECIP GUIDANCE IS MUCH
MORE ROBUST THAT THE ECMWF...BUT BETTER DEFINITION OF THIS SYSTEM
WILL COME WITH SUBSEQUENT RUNS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1234 PM CDT MON JUL 21 2014

MUCH OF NE MINNESOTA AND NW WISCONSIN HAD VFR CONDITIONS EARLY
THIS AFTERNOON. THERE WAS A BAND OF BKN/SCT MVFR CIGS OVER PARTS
OF NE MINNESOTA...SO KHIB AND KBRD COULD SEE BRIEF PERIODS OF MVFR
CIGS EARLY THIS AFTERNOON. THIS BAND WILL LIKELY SCATTER OUT
DURING THE MIDDLE AFTERNOON.

THERE WILL BE INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS FROM
THE WEST THIS EVENING. THERE IS A POTENTIAL FOR STORM COMPLEX TO
FORM IN THE NORTHERN PLAINS LATE THIS AFTERNOON AND EARLY THIS
EVENING...AND THEN SPREAD INTO NE MINNESOTA LATER THIS EVENING.
THIS STORM COMPLEX...IF IT FORMS AND HEADS INTO NE
MINNESOTA...COULD BRING SEVERE WEATHER...INCLUDING DAMAGING
WINDS...HAIL...AND HEAVY RAIN. THE STORMS COULD MAKE IT AS FAR
EAST AS KHYR IN NW WISCONSIN LATER TONIGHT...BUT THE GREATEST
THREAT IS FOR THE KBRD AND KINL AREAS.

THERE WILL LIKELY BE LOWERING CIGS LATER TONIGHT IN THE WAKE OF
THE SYSTEM. MOST TERMINALS COULD SEE A PERIOD OF IFR/MVFR
CIGS/VSBYS THROUGH TUESDAY MORNING. GUSTY NW TO NORTHERLY WINDS
WILL LIKELY DEVELOP DURING THE MIDDLE TO LATE MORNING TOMORROW.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  66  76  49  71 /  80  30   0   0
INL  63  76  50  75 /  80  10   0   0
BRD  69  80  55  78 /  70  10   0   0
HYR  71  81  53  75 /  80  30  10   0
ASX  68  76  51  69 /  80  50  10   0

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR MNZ025-026-033>038.

WI...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR WIZ001-006.

LS...NONE.
&&

$$

UPDATE...LE
SHORT TERM...GSF
LONG TERM...CLC
AVIATION...GROCHOCINSKI