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000
FXUS63 KDLH 310520
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1220 AM CDT THU JUL 31 2014

.UPDATE...
ISSUED AT 1219 AM CDT THU JUL 31 2014

UPDATED FOR AVIATION SECTION BELOW.

UPDATE ISSUED AT 625 PM CDT WED JUL 30 2014

UPDATED TO FRESHEN UP PRECIPITATION AND SKY TRENDS. ALSO UPDATED
AVIATION SECTION BELOW.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 245 PM CDT WED JUL 30 2014

THE UNSTABLE NORTHWEST FLOW AND STEEP LAPSE RATES HAVE ALLOWED FOR
ANOTHER AFTERNOON OF SCATTERED SHOWERS...AND A FEW THUNDERSTORMS.
THE CONVECTION WILL CONTINUE THROUGH THE EARLY EVENING...THEN
DIMINISH THROUGH SUNSET WITH THE LOSS OF DIURNAL HEATING. WITH CAPE
VALUES AROUND 1000 J/KG...AND RELATIVELY LOW FREEZING
LEVELS...SOME HAIL IS EXPECTED WITH THE STRONGER STORMS THIS
AFTERNOON. THE MAIN THREAT FOR STRONG TO POSSIBLY A LOW-END SEVERE
STORM WILL BE OVER THE MN ARROWHEAD AND NRN WISCONSIN ZONES WHERE
0-6 KM SHEAR IS MOST FAVORABLE.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 245 PM CDT WED JUL 30 2014

THE EXTENDED PERIOD WILL FEATURE SIGNIFICANT UNCERTAINTY BEGINNING
SUNDAY. THE GFS AND ECMWF CONTINUE TO OFFER DIFFERENT SOLUTIONS FROM
SUNDAY THROUGH WEDNESDAY REGARDING A FRONTAL BOUNDARY AND WHERE IT
HANGS UP.

AN UPPER LEVEL LOW OVER/NEAR JAMES BAY THURSDAY NIGHT WILL MOVE
NORTHEAST LATE IN THE WEEK INTO THE WEEKEND. A WEAK SURFACE LOW WILL
BE OVER THE NORTHLAND THURSDAY NIGHT/FRIDAY...THEN IS FORECAST TO
WEAKEN. WE EXPECT SOME SHOWERS/STORMS TO DEVELOP ONCE AGAIN FRIDAY
AFTERNOON OVER PORTIONS OF THE NORTHLAND...WITH SOUTHERN AREAS
SEEING THE HIGHEST PROBABILITY. THE PRECIP WILL END FRIDAY NIGHT AND
MUCH OF THE REGION WILL REMAIN DRY INTO SATURDAY. A FRONTAL BOUNDARY
WILL THEN MOVE INTO NORTHWEST MINNESOTA SATURDAY AFTERNOON BRINGING
A CHANCE FOR SHOWERS/STORMS TO WESTERN PORTIONS OF THE CWA.

THE MODELS DIVERGE IN HOW FAR SOUTH THEY BRING THIS BOUNDARY...WITH
THE ECMWF CONSISTENTLY FURTHER SOUTH THAN THE GFS. THIS WILL HAVE A
BIG IMPACT ON THE REGIONS WEATHER AS INSTABILITY AND LIFT WILL BE
SIGNIFICANT ALONG THE FRONT. THE MODELS ARE INDICATING HEAVY RAIN AS
SEVERAL ROUNDS OF THUNDERSTORMS WILL OCCUR LATE IN THE WEEKEND INTO
THE MIDDLE OF NEXT WEEK ALONG THIS BOUNDARY. AT THIS TIME WE HAVE
SOME POPS FOR THE SUNDAY-WEDNESDAY PERIOD ACROSS MUCH OF THE
CWA...WITH HIGHEST CHANCES MOST TIMES OVER SOUTHERN AREAS CLOSER TO
THE BOUNDARY. THE PERIOD BEARS CLOSE MONITORING AS HEAVY RAIN/SEVERE
WEATHER WILL BE ASSOCIATED WITH THIS BOUNDARY. IF THE ECMWF IS
CORRECT MUCH OF THE STRONGER STORMS WILL REMAIN SOUTH OF OUR
CWA...AND THE GFS SOLUTION PUTS OUR CWA IN THE CROSSHAIRS.

EXPECT HIGH TEMPERATURES FROM THE MID SEVENTIES TO LOWER EIGHTIES
FOR MOST AREAS. THE WARMEST TEMPERATURES SHOULD OCCUR SATURDAY
BEFORE THE FRONTAL BOUNDARY MOVES IN.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1219 AM CDT THU JUL 31 2014

VFR SHOWERS LINGERING OVER THE AREA SHOULD DISSIPATE IN THE NEXT
HOUR OR SO. OVERNIGHT FOG TO AFFECT SEVERAL TERMINALS WITH IFR TO
LIFR VISIBILITIES AND CIGS...BUT THEN SHOULD DISSIPATE BY 15Z. CONVECTION
EXPECTED TO DEVELOP AGAIN THURSDAY AFTER 18Z...BUT SHOULD STAY
AWAY FROM THE TERMINALS. EXPECT VFR CONDITIONS AGAIN THROUGH THE
REMAINDER OF THE TAF PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  55  79  56  77 /  20  20  10  20
INL  53  79  52  79 /  10  20  10  10
BRD  56  82  57  81 /  10  20  10  30
HYR  53  81  54  79 /  20  30  20  50
ASX  53  74  53  74 /  30  20  10  30

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

$$

UPDATE...LE
SHORT TERM...GRANING
LONG TERM...MELDE
AVIATION...LE