Area Forecast Discussion
Issued by NWS Duluth, MN

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000
FXUS63 KDLH 191345
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
845 AM CDT SAT JUL 19 2014

.UPDATE...
ISSUED AT 844 AM CDT SAT JUL 19 2014 B

ROKEN LINE OF SHOWERS AND THUNDERSTORMS HAS FORMED FROM THE
ARROWHEAD THROUGH DLH TO NEAR MILLE LACS. THIS LINE IS ASSOCIATED
WITH SMALL AREA OF INSTABILITY MOVING THROUGH THE AREA OUT AHEAD
OF THE FRONT. THE PRECIPITATION SHOULD REMAIN SCATTERED AS IT
MOVES INTO NW WI BY MID-MORNING. THERE COULD BE SOME AREAS THAT
COULD RECEIVE UPWARD TO A QUARTER OF AN INCH IN THE HEAVIER
SHOWERS OR THUNDERSTORMS. REST OF FCST UNCHANGED.

UPDATE ISSUED AT 732 AM CDT SAT JUL 19 2014

MADE SOME ADJUSTMENTS FOR THE ONGOING SHOWERS AND LACK OF THUNDER
ATTM. ALSO TWEAKED THE POPS MENTION FOR THIS AFTERNOON IN NW WI.
REST OF THE FORECAST ON TRACK.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT SAT JUL 19 2014

AN AREA OF THUNDERSTORMS WAS MOVING THROUGH THE NW CORNER OF THE FA
AT 08Z. THIS WAS AHEAD OF A COLD FRONT IN EASTERN ND AND LOCATED
NEAR AN AREA OF UPPER LEVEL DIVERGENCE. EXPECT THE THUNDERSTORMS TO
PROPAGATE EWD WITH MOVEMENT WITHIN THE LINE TO THE NNE. STORMS
SHOULD WEAKEN AS THE UPPER LEVEL DIVERGENCE DEPARTS AND THEY HAVE
MOVED TOO FAR AWAY FROM LOW LEVEL CONVERGENCE. WILL CONTINUE TO
CARRY LOW POPS THROUGH THE MORNING HOWEVER AS MODELS SUGGEST SOME
ADDITIONAL DEVELOPMENT IS POSSIBLE FROM THE ARROWHEAD TO THE TWIN
PORTS AND THE MILLE LACS AREA. THE COLD FRONT IS FORECAST TO REACH
THE WESTERN EDGE OF THE FA BY 18Z. MEANWHILE...AN UPPER LEVEL SHORT
WAVE TROF INTERACTS WITH THE COLD FRONT TO INITIATE ANOTHER LINE OF
STORMS FROM THE ARROWHEAD TO THE I35 CORRIDOR...REACHING INTO NW WI
BY 19Z. TIMING AND AREAL COVERAGE WILL BE TOUGH TO ASCERTAIN GIVEN
THE WAA AHEAD OF THESE FEATURES. HAVE CHANCE POPS THROUGH THE
AFTERNOON AHEAD OF THE FRONT. THERMODYNAMIC PROFILES SUGGEST GENERAL
THUNDERSTORMS AS INSTABILITY WILL BE WEAK.

THE FRONT WEAKENS THIS EVENING AS IT CROSSES INTO NW WI. UPPER LEVEL
SUPPORT WILL MOVE E LEAVING LOW LEVEL CONVERGENCE AS THE ONLY
INITIATOR OF STORMS. THIS IS CENTERED IN NW WI AND HAVE POPS IN
PLACE IN THE EVENING. THE FRONT IS NO LONGER EVIDENT AFTER 06Z.
UPPER LEVEL FLOW HAS BECOME WESTERLY AND BEST FORCING IS IN CANADA
NEAR SFC LOW IN NORTHERN MANITOBA BY 12Z SUNDAY. SWLY FLOW AND WAA
CONTINUES AS MID LEVEL RIDING BEGINS TO BUILD INTO THE FA. HAVE
REMOVED POPS FROM 03Z ONWARD AS A RESULT.

THE PUSH OF WARM AND HUMID AIR CONTINUES ON SUNDAY. A CAPPING
INVERSION BEGINS TO BUILD INTO THE FA FROM THE SW AS H7 TEMPS REACH
10C AND COVERS THE FA BY 00Z MONDAY. THE EXCEPTION WILL BE RIGHT
ALONG THE INTERNATIONAL BORDER WHERE THE MID LEVEL CAP WILL NOT BE
AS STRONG. ANOTHER FRONTAL BOUNDARY MOVES INTO NW MN LATE IN THE
AFTERNOON AND STORMS ARE PROGGED TO DEVELOP IN THE VCNTY. UPPER
LEVEL FORCING WILL BE WELL N OF THE BORDER...BUT THERE MAY BE ENOUGH
LOW LEVEL CONVERGENCE TO INITIATE SOME STORMS AND HAVE CHANCE POPS
IN THE NW CORNER OF THE FA. DRY ELSEWHERE AS THE ATMOSPHERE HAS
CAPPED.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 334 AM CDT SAT JUL 19 2014

ONGOING STRONG WARM AIR ADVECTION WILL START OUT THE WORK WEEK. BY
MONDAY EVENING 8H TEMPS WILL HAVE RISEN INTO THE 20-25 DEGREES C
RANGE AND BROUGHT ON A STRONG 40 KT 8H JET.  THIS WILL SET THE STAGE
FOR ANOTHER ROUND OF STORMS MAINLY MONDAY NIGHT.  AS LOW PRESSURE
NEAR THE REGION FROM THE WEST AS A WARM FRONT WILL MOVE NORTH ACROSS
THE REGION. THE GFS AND ECMWF DEPICT THE FRONT MUCH FARTHER SOUTH
OVER CENTRAL MN/WI COMPARED TO THE MUCH FARTHER NORTH NAM. THE MORE
SOUTHERN POSITION WILL PUT THE NORTHLAND NORTH OF THE FRONT...THE
PRIME AREA OF THUNDERSTORM DEVELOPMENT. WITH INCREASING WAA AND
MOISTURE TRANSPORT...ALONG WITH STRONG FGEN AND AIDED BY A STRONG
UPPER LEVEL VORT MAX...EXPECT A WIDESPREAD THUNDERSTORM SCENARIO. IT
WILL BE VERY UNSTABLE WITH MUCAPES FCST TO BE IN THE 5000 J/KG AND
LI`S BLO -10.

MONDAY WILL ALSO BE A VERY WARM AND HUMID DAY WITH TEMPS WELL INTO
THE 80S AND DEW POINTS IN THE UPPER 60S AND LOWER 70S. THIS WILL
GIVE HEAT INDICES IN THE 90S. NOT AT ADVISORY LEVELS...BUT SOMETHING
TO KEEP AN EYE ON AND ADVERTISE SINCE THIS TYPE OF HEAT HAS NOT BEEN
EXPERIENCED FOR QUITE SOME TIME.

ONCE THIS SYSTEM GOES THRU MONDAY NIGHT ANOTHER UPPER WAVE WILL
COME THROUGH TO BRING MORE STORMS TUESDAYS/TUESDAYS NIGHT. AFTER
THAT THE REMAINDER OF THE WORK WEEK WILL BE DRY UNDER STRONG
RIDGING. THEN INTO THE WEEKEND A PACIFIC LOW WILL MOVE ONSHORE AND
BRING A CHANCE OF THUNDERSTORMS AS IT MOVES THROUGH THE RIDGE.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 650 AM CDT SAT JUL 19 2014

A FRONTAL SYSTEM WILL MOVE FRONT NORTHWEST MN INTO NORTHEAST
MN...THEN BECOME QUASI-STATIONARY. A FEW SHOWERS AND THUNDERSTORMS
ARE POSSIBLE AROUND THE FRONT.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  77  61  81  65 /  30  10  10  40
INL  76  57  86  67 /  10  10  30  50
BRD  80  65  88  69 /  10  10  10  30
HYR  79  64  84  67 /  30  20  10  30
ASX  79  62  86  66 /  30  20  10  30

&&

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

$$

UPDATE...STEWART
SHORT TERM...GSF
LONG TERM...CLC
AVIATION...CLC






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