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000
FXUS63 KDLH 281126
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
526 AM CST WED JAN 28 2015

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 353 AM CST WED JAN 28 2015

LOW PRESSURE WAS ORGANIZING IN THE DAKOTAS AT 08Z WITH A FRONTAL
BOUNDARY EXTENDING NORTHEASTWARD INTO SOUTHERN MANITOBA AND INTO NW
ONTARIO. IN THE WAA AHEAD OF THIS SYSTEM...SOME LIGHT SNOW WAS
FALLING OVER THE ARROWHEAD WITH LITTLE ACCUMULATION. NORTH OF THE
CANADIAN BORDER...SOME LIGHT FREEZING RAIN WAS OCCURRING RIGHT NEAR
THE FRONT FROM WINNIPEG TO NEAR DRYDEN. LATEST SHORT TERM HRRR AND
RAP KEEP THIS FREEZING RAIN NORTH OF THE BORDER. THE LIGHT SNOW OVER
THE ARROWHEAD IS EXPECTED TO SLOWLY END BY NOON. LITTLE ADDITIONAL
ACCUMULATION IS ANTICIPATED.

BY THIS AFTERNOON...THE SFC LOW MOVES EASTWARD WITH THE LOW CENTER
BEGINS TO REORGANIZE AND DRIFT INTO SOUTHWEST IOWA BY 00Z THURSDAY.
MEANWHILE...A MID LEVEL LONG WAVE TROF MOVES OVER THE WESTERN GREAT
LAKES. SOME MODEL DIFFERENCES BEGIN TO REVEL THEMSELVES WITH RESPECT
TO QPF PLACEMENT AND THE AMOUNT OF COLD AIR FORECAST TO DROP INTO
THE FORECAST AREA. THE GFS IS THE MOST ROBUST AND FURTHEST SOUTH
WHILE THE ECMWF HAS LIMITED QPF AND KEEPS IT NEAR THE CANADIAN
BORDER. HAVE USED A BLENDED APPROACH AND KEPT POPS TO THE NORTHERN
HALF OF THE FORECAST AREA BY LATE AFTERNOON. PRECIPITATION TYPE WILL
BE ALL SNOW. LATEST FORECAST SOUNDINGS ARE NOT SUPPORTING THE
MENTION OF FREEZING RAIN OR FREEZING DRIZZLE AND HAVE REMOVED.

TONIGHT...THE MID LEVEL LONG WAVE TROF MOVES EAST OF THE FORECAST
AREA BY 12Z THURSDAY. THIS PUSHES THE SFC LOW EAST OF THE AREA AS
WELL. BEHIND THIS SYSTEM...A TIGHTENING PRESSURE GRADIENT MOVES OVER
THE WESTERN GREAT LAKES AS HIGH PRESSURE BUILDS INTO THE WESTERN
DAKOTAS. MADE SOME MINOR CHANGES TO THE POPS AND THEIR TIMING ACROSS
THE AREA...WITH THE SNOW ENDING LATE TONIGHT OVER THE SOUTHWEST
PORTION OF THE FORECAST AREA TO THE TWIN PORTS LATE TONIGHT.
FORECAST SOUNDINGS INDICATE THAT THE PRECIPITATION TYPE WILL BE ALL
SNOW AND HAVE REMOVED THE MENTION FREEZING RAIN/FREEZING DRIZZLE AND
SLEET. SNOW AMOUNTS WILL BE LIGHT WITH THE HIGHEST AMOUNTS OF AROUND
ONE HALF INCH FOUND ALONG THE CANADIAN BORDER.

ON THURSDAY...ONLY MADE SOME MINOR CHANGES TO THE POPS AND WEATHER
AS MODELS ARE IN VERY GOOD AGREEMENT. WILL STILL HAVE GUSTY WINDS AS
THE TIGHT PRESSURE GRADIENT REMAINS UNTIL LATE AFTERNOON WHEN THE
AFOREMENTIONED HIGH PRESSURE MOVES INTO THE RED RIVER VALLEY. A NW
WIND OVER LAKE SUPERIOR AND CAA WILL LEAD TO SOME LAKE EFFECT SNOW
ALONG THE HIGHER TERRAIN OF THE SOUTH SHORE. SNOW AMOUNTS WILL BE
LIGHT HOWEVER AS DEEP COLD AIR IS LACKING UNTIL LATE AFTERNOON.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 353 AM CST WED JAN 28 2015

MUCH COLDER AIR ON THE WAY FOR THIS WEEKEND WITH A CHANCE FOR SNOW
FROM...YOU GUESSED IT...ANOTHER WEAK CLIPPER SYSTEM. THE LARGE SCALE
PATTERN WILL UNDERGO SOME CHANGES THROUGH THE LONG TERM THAT WILL
/AT LEAST TEMPORARILY/ PUT A STOP TO WHAT HAS BEEN A LONG PERIOD OF
WEAK /AND FRANKLY DISAPPOINTING FOR SNOW LOVERS/ CLIPPERS.
TEMPERATURES WILL DROP FROM WHAT HAS BEEN A VERY MILD PATTERN TO A
COLDER REGIME...ENDING THE LAST WEEK OF JANUARY WITH TEMPS SIMILAR
TO THE FIRST WEEK OF THE MONTH.

ON THE SYNOPTIC SCALE A SERIES OF STRONG ARCTIC AIR MASSES WILL DROP
DOWN INTO THE NORTHERN PLAINS AND UPPER MIDWEST. LATE THIS WEEK AN
AREA OF HIGH PRESSURE WILL MOVE OVER THE AREA THURSDAY NIGHT
FOLLOWED BY A WEAK CLIPPER ON FRIDAY/FRIDAY NIGHT. THEN LATE IN THE
WEEKEND A DEEP LONGWAVE TROUGH AT MID-LEVELS WILL DESCEND OVER THE
MIDWEST LEADING TO VERY COLD AIR ALOFT...850MB TEMPS APPROACHING THE
COLDEST 10 PERCENT OF CLIMATOLOGY IN THE MID -20S C /COMPARED TO 00Z
TODAY WHEN THEY WERE IN THE WARMEST 10 PERCENT OF CLIMO AT AROUND
0C/.

BEST CHANCE FOR SNOWFALL ACROSS THE REGION WILL BE LATE FRIDAY
AFTERNOON INTO FRIDAY NIGHT A CLIPPER MOVES ACROSS. GFS AND ECMWF IN
GOOD AGREEMENT ON TIMING...WITH ECMWF PESSIMISTIC ON INTENSITY AND
GFS A LITTLE STRONGER WITH A DEEPER MOISTURE PROFILE. GEM WAS SLOWER
AND NOT AS INTENSE OVERALL...BUT THIS WAS A PRETTY BIG CHANGE FROM
12Z GEM WHICH WAS FASTER AND MUCH MORE AGGRESSIVE ON PRECIP. AT THIS
POINT IT LOOKS LIKE A QUICK INCH OR TWO FOR NORTHERN MINNESOTA NORTH
OF HIGHWAY TWO. OTHERWISE NO SIGNIFICANT CHANCES FOR PRECIP IN THE
SEVEN DAY FOR MUCH OF THE REGION...WITH THE EXCEPTION OF LAKE EFFECT
SNOWFALL ALONG PORTIONS OF THE SOUTH SHORE OF LAKE SUPERIOR.

LAKE EFFECT SNOWFALL WILL BE PRESENT THROUGH MUCH OF THE LONG TERM
PERIOD. ON THURSDAY NIGHT CONDITIONS WILL BE GOOD FOR LAKE EFFECT
SNOWFALL ALONG THE HIGHER TERRAIN OF IRON/ASHLAND COUNTIES WITH
STEEP LOW LEVEL LAPSE RATES THROUGH 850MB AND GREAT NORTH/NORTHWEST
FLOW OVER THE LAKE. ICE COVERAGE ON THE SOUTH SHORE MAY LIMIT THE
INTENSITY OF LAKE EFFECT SNOWFALL...AND OPTED TO LEAVE NORTHERN
BAYFIELD COUNTY OUT OF HIGHER CHANCES FOR LAKE EFFECT SNOWFALL DUE
TO WHAT WOULD BE A VERY LIMITED FETCH LENGTH. LOW LEVEL MOISTURE
WILL ALSO BE A FACTOR AS NAM/GFS/ECMWF DEPICT A NEAR-SURFACE DRY
LAYER...SO IT MAY TAKE A WHILE TO SATURATE LOW LEVELS AND THUS LIMIT
SNOWFALL AMOUNTS. LAKE EFFECT WILL TAPER OFF AS HIGH PRESSURE MOVES
OVER LAKE SUPERIOR ON FRIDAY AFTERNOON...BUT RAMP BACK UP AGAIN ON
SATURDAY AND THROUGH ABOUT TUESDAY DUE TO THE VERY COLD AIRMASS THAT
WILL BE IN PLACE.

TEMPS WILL BE ON A DOWNWARD TREND...AND HAVE ADJUSTED SOME OF THE
USUAL COLD SPOTS A LITTLE COLDER THAN INITIAL GUIDANCE TO ACCOUNT
FOR THE ARCTIC HIGHS THAT WILL BE OVER NORTHEASTERN MINNESOTA IN THE
LONG TERM. HIGHS IN THE MID TEENS TO MID 20S ON SATURDAY...THEN THE
SINGLE DIGITS ON SUNDAY AND MONDAY BEFORE RECOVERING TO THE TEENS
TUESDAY. LOWS NEAR ZERO TO TEN OR MORE BELOW ZERO ON THURSDAY
NIGHT...MILD FRIDAY NIGHT DUE TO WEAK SOUTHERLY WINDS...THEN 0 TO
-15 SATURDAY NIGHT AND 10 TO 20 BELOW ZERO ON SUNDAY NIGHT. MONDAY
MORNING WILL BE THE COLDEST PERIOD IN THE LONG TERM WITH WIND CHILL
VALUES OF 25 TO 35 BELOW ZERO...AND COLD SPOTS IN THE TIP OF THE
ARROWHEAD REGION NEAR 40 BELOW ZERO.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 526 AM CST WED JAN 28 2015

GENERALLY IFR CONDITIONS THROUGH MOST OF THE TAF PERIOD AT ALL SITES
DUE TO LOW CEILINGS AND PATCHY FOG DEVELOPING. AS OF THIS MORNING
ALL TAF SITES EXCEPT FOR INL WERE ALREADY AT IFR CONDITIONS...WITH
INL CEILINGS EXPECTED TO WORSEN LATER THIS MORNING. THERE WILL BE
LITTLE IMPROVEMENT THROUGH THE DAY WITH SOME SITES POSSIBLY
DETERIORATING TO LIFR CEILINGS AND IFR VISIBILITY THIS AFTERNOON.
TONIGHT A COLD FRONT WILL MOVE THROUGH WHICH WILL IMPROVE
CONDITIONS...WITH CEILINGS IMPROVING TO MVFR LEVELS. WINDS WILL BE
LIGHT TODAY OUT OF THE SOUTH...BUT BEHIND THE COLD FRONT LATE
TONIGHT WINDS WILL RAPIDLY INCREASE TO BECOME 10 TO 15 KTS OUT OF
THE WEST WITH GUSTS APPROACHING/EXCEEDING 30 KTS AT TIMES. DID NOT
INCLUDE STRONG WINDS IN ALL TAFS SINCE TIMING WILL BE RIGHT AROUND
END OF THE TAF PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  31  24  24  -1 /  10  50  10   0
INL  32  16  16 -10 /  30  60  10   0
BRD  34  22  22   5 /  10  40   0   0
HYR  33  27  27  -2 /  10  50  20   0
ASX  34  27  27   2 /  10  50  20  20

&&

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

$$

SHORT TERM...GSF
LONG TERM...JJM
AVIATION...JJM