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000
FXUS63 KDLH 081730
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1130 AM CST SAT MAR 8 2014

.UPDATE...
ISSUED AT 925 AM CST SAT MAR 8 2014

UPDATED TO EXTEND FLURRIES ALONG LAKESHORE THROUGH NOON AS
OBSERVATIONS AND REPORTS INDICATE THE LIGHT PRECIPITATION
UNDERNEATH THE CLOUDS. ALSO...SLOWED TREND OF DECREASING
CLOUDINESS UNTIL EARLY AFTERNOON BASED ON CURRENT TRENDS AND
MODELS.  REST OF FCST UNCHANGED.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CST SAT MAR 8 2014

AT 315AM/0915Z...THERE WAS A SURFACE HIGH PRESSURE SYSTEM CENTERED
OF THE EASTERN DAKOTAS. MUCH OF THE NORTHLAND HAD CLOUDY SKIES
WITH LIGHT NORTHERLY WINDS...BUT AREAS FARTHER NORTH AND WEST HAD
CLEAR SKIES AND CALM WIND. THE CLOUDY SKIES...AROUND 2 KFT...WERE
PRODUCING SOME FLURRIES. A MID LEVEL WARM FRONT WAS MOVING EAST
THROUGH THE DAKOTAS...BRINGING INCREASING WESTERLY WINDS IN THE
MID LEVELS WITH CLOUDY SKIES AROUND 4 TO 8 KFT.

MAIN CONCERN TODAY IS CLOUD COVER. THIS FORECAST IS TRICKY BECAUSE
THE MODELS ARE NOT HANDLING THE CLOUD COVER...ESPECIALLY THE
CURRENT LOW LEVEL CLOUD COVER EARLY THIS MORNING. I LEANED ON
SATELLITE TRENDS FOR THE NEXT SEVERAL HOURS...AND THEN A MODEL
BLEND FOR THE REST OF THE DAY. THE LOW CLOUD COVER ACROSS THE
NORTHLAND EARLY THIS MORNING SEEMS TO BE SLOWLY ERODING FROM THE
NORTH AS THE HIGH PRESSURE BEGINS TO SHIFT INTO THE REGION. I
EXPECT THIS CLOUD COVER TO AT LEAST LINGER UNTIL LATE THIS
MORNING. THE MODELS ARE ALSO NOT HANDLING THE CLOUD COVER STEADILY
MOVING SOUTH AND EAST ACROSS THE DAKOTAS AND BEGINNING TO MOVE
INTO WESTERN MINNESOTA BEHIND THE MID LEVEL WARM FRONT. THE
INCREASING FLOW BEHIND THE FRONT IS LIKELY RESULTING IN SPEED
CONVERGENCE AND SATURATION...AND THIS ASSOCIATED CLOUD COVER COULD
MOVE INTO AT LEAST THE WESTERN OR SOUTHERN FORECAST AREA THIS
MORNING. FOR NOW I LEANED ON A SUNNIER MODEL CONSENSUS...BUT WE
MIGHT NEED TO INCREASE CLOUD COVER LATER IN THIS SHIFT.

THE TEMPERATURE FORECAST TODAY IS A BIT HIGHER THAN THE PREVIOUS
FORECAST AND IS ASSUMING WE GET PLENTY OF SUNSHINE UNTIL AT LEAST
LATE THIS AFTERNOON. HOWEVER...IF THE CLOUD COVER IN THE DAKOTAS
MOVES INTO THE REGION FASTER THAN EXPECTED...THEN WE MIGHT NEED TO
INCREASE THE HIGH TEMPERATURE FORECAST.

THE WESTERLY MID LEVEL FLOW WILL CONTINUE TO INCREASE TONIGHT IN
THE WAKE OF THE MID LEVEL WARM FRONT. THE LOW LEVEL SW WINDS WILL
INCREASE TOO. THE INVERSION AND WARM SW FLOW WILL LIKELY RESULT
IN INCREASING LOW LEVEL MOISTURE AND CLOUD COVER...AND
TEMPERATURES TO RISE LATER TONIGHT. I ADDED PATCHY FOG TO THE
FORECAST BECAUSE THE WARM SW FLOW AND MOISTURE FROM THE SNOW PACK
COULD CAUSE FOG. A CANADIAN CLIPPER SYSTEM COULD BRING A DUSTING
OF SNOW TO THE TIP OF THE ARROWHEAD TONIGHT...BUT OTHERWISE THE
SNOW AND PCPN SHOULD REMAIN NORTH AND EAST OF THE FORECAST AREA.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 315 AM CST SAT MAR 8 2014

A ZONAL FLOW WITH WARMING H85 TEMPS WILL PUSH ACROSS THE REGION
SUNDAY. THERE REMAINS UNCERTAINTY IN CLOUDS/TEMPS SUNDAY DUE TO
MELTING/NEAR SFC MOISTURE...AND WILL BE HIGHLY DEPENDENT IN THE
STRENGTH OF THE OVERNIGHT INVERSION. AT THIS TIME...EXPECTING THAT
THE DAYTIME HEATING/WINDS WILL PROMOTE ENOUGH MIXING TO CLEAR OUT
ANY MORNING STRATUS/FOG. IF THE INVERSION IS ABLE TO BREAK AND
SKIES CLEAR...TEMPERATURES HAVE THE POTENTIAL TO BE A GOOD 5-10F
HIGHER THAN IN THE FORECAST ATTM.

MEANWHILE...A PAIR OF FAST MOVING VORTS WILL TRACK ACROSS
ONTARIO...SUNDAY MORNING AND AGAIN LATE SUNDAY NIGHT/MONDAY.
ALTHOUGH THE BULK OF THE PRECIP IS EXPECTED TO REMAIN NORTH OF THE
BORDER...HAVE INCREASED TO CHC POPS ALONG THE
BORDERLAND/ARROWHEAD FOR LIGHT QPF AMOUNTS. MODELS ARE IN
AGREEMENT THAT THE 2ND WAVE...FORECAST FOR LATE SUNDAY
NIGHT/MONDAY...IS THE STRONGER OF THE TWO WITH A WELL DEFINED SFC
LOW.

A CYCLONIC FLOW AND COLD AIR ADVECTION REGIME RETURNS MONDAY NIGHT
THROUGH TUESDAY. HAVE BROAD BRUSH LOW POPS FOR RAIN/SNOW TUESDAY
AS THE COLD AIR PROMOTES STEEP LAPSE RATES AND POTENTIAL FOR
INSTABILITY SHOWERS...MAINLY OVER THE MN ARROWHEAD/IRON RANGE
ZONES. LONG RANGE MODELS IN GOOD AGREEMENT THAT WED/THURS BRINGS
AN APPROACHING UPPER LVL RIDGE WITH WARMING MID LEVELS. TEMPS
DURING THIS TIME WILL BE NEAR OR SLIGHTLY ABOVE NORMAL. LATE IN
THE WEEK...FRIDAY/SATURDAY...A CLIPPER WILL DROP OUT OF CANADA AND
SWEEP A COLD FRONT ACROSS THE NORTHLAND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1130 AM CST SAT MAR 8 2014

VFR UNTIL 08Z WHEN MVFR CIGS ARRIVE AHEAD OF A WARM FRONT. LLWS
WILL ALSO BE FOUND AHEAD OF THE WARM FRONT. BY 12Z...MIXING WILL
OCCUR BEHIND THE FRONT ENDING THE LLWS AND THE MVFR CIGS IMPROVE
TO VFR.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  25  14  41  28 /  10   0  10  10
INL  23  12  39  26 /   0   0  10  30
BRD  25  15  44  31 /   0   0   0  10
HYR  25  10  41  27 /  10   0  10  10
ASX  27  12  42  29 /  10   0  10  10

&&

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

$$

UPDATE...STEWART
SHORT TERM...GROCHOCINSKI
LONG TERM...GRANING
AVIATION...GSF