Area Forecast Discussion
Issued by NWS Duluth, MN

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000
FXUS63 KDLH 220030
AFDDLH

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

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 434 PM CDT MON JUL 21 2014

HOT AND HUMID OUT THERE TODAY...WITH THE WARMEST TEMPERATURES WE
HAVE HAD ALL YEAR COMBINED WITH DEWPOINTS IN THE LOW 70S.  HEAT
INDEXES OVER THE SOUTHWEST PARTS OF THE CWA HAVE BEEN IN THE 95 TO
105 SO FAR TODAY...WITH EVEN DULUTH IN THE UPPER 80S WITH A HEAT
INDEX FROM 95- AROUND 100.  THIS AIRMASS IS AFFECTING MOST OF
NORTHERN MINNESOTA...WISCONSIN AND THE EASTERN DAKOTAS.  A STRONG
SURFACE LOW OVER NORTHWEST SOUTH DAKOTA IS ASSOCIATED WITH A WARM
FRONT THAT EXTENDS FROM IT NORTHEAST ACROSS NORTH DAKOTA AND FAR
NORTHERN MINNESOTA AND ON UP INTO ONTARIO.  A STRONG UPPER LEVEL JET
IS UP OVER  SOUTHERN CANADA...WITH SOME STRONG WESTERLIES AT THE MID
LEVELS OVER MUCH OF THE NORTHERN PLAINS STATES.  OUR WARM SECTOR HAS
DEVELOPED CAPE VALUES IN THE 3-5 THOUSAND J/KG IN THIS AIRMASS...BUT
AN EML OVER THIS SAME AREA HAS PLACED A CAP OVER MUCH OF MINNESOTA
AND GENERALLY SOUTH OF THE FRONT. DEEP CONVECTION HAS FORMED OVER
WESTERN NORTH DAKOTA AND IS PRODUCING SEVERE WEATHER THERE...WHERE
THE INSTABILITY WEAKEST CAP AND BEST FORCING ARE.

TONIGHT WILL BE VERY VERY INTERESTING CONVECTION WISE...WITH THE
MAIN CONCERNS THE TRACK AND TIMING OF THE SEVERE MCS THAT WILL MOVE
ACROSS THE CWA TONIGHT.  CURRENT CONVECTION CAN BE EXPECTED TO
CONTINUE TO GROW AND MOVE EAST...LIKELY ACCELERATING FOR THE NEXT
SEVERAL HOURS.  THIS CONVECTION CAN BE EXPECTED TO GET INTO THE
WESTERN PORTIONS OF THE FORECAST AREA SOMETIME BETWEEN 7 AND 10 PM
THIS EVENING...THEN CONTINUING EAST ACROSS THE FORECAST AREA.
DAMAGING WINDS LOOK LIKELY...WITH LARGE HAIL A SECONDARY POSSIBILITY
THOUGH WITH ALL THIS HEAT AROUND WEB BULB ZEROS ARE A BIT HIGH.
FOR NOW...IT LOOKS LIKE THE MAIN AXIS OF STRONG STORMS WILL RUN
RIGHT ACROSS THE CENTER OF THE FORECAST AREA...WITH ADDITIONAL
SHOWERS AND THUNDERSTORMS ALONG AND NORTH OF THAT AREA. THUS...IT
LOOKS LIKE THE ENTIRE FORECAST AREA IS LOOKING AT A SHOT OF SHOWERS
AND THUNDERSTORMS...WITH THE NORTHERN AND CENTRAL CWA GETTING A
PERIOD OF HEAVY RAIN.  AM CARRYING CATEGORICAL POPS FOR NEARLY THE
WHOLE CWA OVERNIGHT.   AS FOR TEMPERATURES...HIGH HEAT INDEX VALUES
TO CONTINUE INTO THIS EVENING WITH THE HIGH DEWPOINTS ONLY TO RISE
THE NEXT FEW HOURS AS POOLING AHEAD OF THE BOUNDARY APPROACHES.  THE
CONVERGENCE NEAR THE BOUNDARY ALONG WITH WARM AIR ADVECTION TO ALSO
KEEP TEMPERATURES WARM INTO THE EVENING HOURS.  THUS...THE HEAT
ADVISORY WILL NOT LIKELY BE CANCELLED EARLY...AND MAY EVEN NEED TO
BE EXTENDED IF TEMPERATURES STAY UP THROUGH SUNSET.  OVERNIGHT MIN
TEMPS TO REMAIN MILD WITH LOWS IN THE MID 60S TO LOW 70S.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 434 PM CDT MON JUL 21 2014

THERE COULD BE LINGERING RAIN AND ISOLATED THUNDER TUESDAY IN THE
WAKE OF THE STORM COMPLEX THAT WILL LIKELY SWEEP THROUGH THE
NORTHLAND TONIGHT. THERE COULD BE HEAVY RAINFALL OVER NE MINNESOTA
NORTH OF HIGHWAY 2...SUCH AS THE IRON RANGE AND THE ARROWHEAD. THE
CHANCES OF SHOWERS AND STORMS WILL GRADUALLY SHIFT EAST THROUGH THE
DAY...AND CLEARER SKIES WILL DEVELOP AND SPREAD EAST.

HIGH PRESSURE IS EXPECTED TO PROVIDE THE MIDDLE OF THE WEEK WITH DRY
AND COOLER WEATHER.

THE MODELS INDICATE A MID LEVEL RIDGE WILL DEVELOP OVER THE HIGH AND
CENTRAL PLAINS LATER THIS WEEK...AND AN UPPER LEVEL LOW OVER THE
PACIFIC NW WILL GET OFF AS IT LIFTS INTO SOUTHERN ALBERTA AND WITH
THE UPPER LOW AND ITS SURFACE REFLECTION COULD SWING THROUGH THE
NORTHLAND OVER THE WEEKEND AND BRING A PERIOD OF CHANCES FOR SHOWERS
AND STORMS.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 714 PM CDT MON JUL 21 2014

VFR WITH SCT LOW CLOUDS THIS EVENING. STRONG/SEVERE THUNDERSTORMS
WILL SPREADING EAST ACROSS THE FORECAST AREA AFTER 03Z. THE STORMS
ARE EXPECTED TO MOVE INTO THE KINL/KBRD AREA AROUND 04Z...REACH
KDLH/KHIB AROUND 06Z...THEN TRACK OVER NORTHERN WISCONSIN AND
IMPACT THE KHYR AREA AFTER 09Z.

ANY STORMS OVERNIGHT WILL HAVE THE POTENTIAL TO PRODUCE DAMAGING
WINDS IN EXCESS OF 60 KT...DAMAGING HAIL...AND TORRENTIAL
RAINFALL. THE GREATEST THREAT FOR SEVERE STORMS WILL BE IN THE
KBRD/KINL/KHIB AREAS.

CEILINGS WILL LOWER TO MVFR/IFR WITH THE ARRIVAL OF THE
STORMS...PERSISTING INTO TUESDAY MORNING WITH FOG/BR AND SHOWERS
LINGERING INTO TUESDAY MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  68  78  55  73 /  90  60   0   0
INL  65  76  52  75 /  90  60   0   0
BRD  70  81  57  78 /  70  20   0   0
HYR  73  82  55  76 /  70  40   0   0
ASX  70  79  54  71 /  70  60   0   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.
&&

$$

SHORT TERM...LE
LONG TERM...GROCHOCINSKI
AVIATION...GRANING






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