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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1208 PM CDT FRI MAR 27 2015

.UPDATE...
ISSUED AT 1035 AM CDT FRI MAR 27 2015

HAVE SENT OUT A QUICK UPDATE FOR THE LATEST TRENDS IN THE VERY
QUIET WEATHER TODAY. HIGH TEMPERATURES IN THE MID TO UPPER 30S
STILL LOOKS GOOD...WITH MIXING UP TO ABOUT 850MB...A DRY AIR MASS AND
OUR DARK TREES WE SHOULD GET ABOUT A 30 DEGREE DIURNAL RANGE
FAIRLY EASILY. LAKE EFFECT SNOW SHOWERS OVER THE SOUTH SHORE OF
LAKE SUPERIOR WINDING DOWN QUITE NICELY...THOUGH THERE MAY BE A
FEW MORE FLURRIES FOR THE REST OF THE MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 308 AM CDT FRI MAR 27 2015

A QUIET WEATHER PATTERN FOR THE BEGINNING OF THE WEEKEND AS AN AREA 
OF HIGH PRESSURE GRADUALLY MOVES ACROSS THE UPPER GREAT LAKES.

EARLY THIS MORNING LAKE EFFECT SNOW SHOWERS WERE OBSERVED OVER PARTS 
OF THE SOUTH SHORE OF LAKE SUPERIOR VIA INFRARED SATELLITE. LOW LEVEL 
WINDS WERE GRADUALLY TURNING FROM NORTH TO NORTHEASTWARD...RESULTING 
IN A LONGER FETCH DEVELOPMENT OVER THE MOSTLY OPEN WATERS. THIS WAS 
ALSO OCCURRING AS THE COLDEST AIR OF THE CURRENT AIR MASS MOVED 
ACROSS THE LAKE...850MB TEMPS OF -15 TO -17 IN WRN LAKE 
SUPERIOR...RESULTING IN A FAVORABLE SFC-H85 TEMP DIFF OF 12 TO 15 
DEGREES CELSIUS. THESE CONDITIONS WILL ONLY LAST THROUGH AROUND 
SUNRISE AS LOW LEVEL TEMPS GRADUALLY WARM UP AND LOW LEVEL 
DIRECTIONAL SHEAR DEVELOPS. UP TO AN INCH IS EXPECTED IN FAR 
NORTHERN IRON AND ASHLAND COUNTIES...WITH JUST A DUSTING ELSEWHERE. 

TODAY...HIGH PRESSURE MOVES OFF TO THE EAST OF THE REGION AS A WEAK 
WARM FRONT WILL DEVELOP IN A BAROCLINIC ZONE IN THE NORTHERN TO 
CENTRAL PLAINS TODAY. WHILE PRECIPITATION WILL REMAIN WEST OF OUR 
REGION...SOME HIGH TO MID LEVEL CLOUDS WILL MOVE ACROSS OVER NORTH 
CENTRAL MINNESOTA DUE TO THIS SYSTEM. SCATTERED CLOUDS FROM LAKE 
EFFECT SNOW SHOWERS MAY LINGER THROUGH THE MORNING IN NORTHWEST 
WISCONSIN...BUT OTHERWISE A SUNNY DAY TODAY ACROSS THE NORTHLAND. 
RELATIVE HUMIDITY VALUES WILL DROP TO 25 TO 35 PERCENT IN THE 
AFTERNOON...BUT FIRE WX CONCERNS WILL BE MINIMAL DUE TO VERY LIGHT 
SOUTHERLY WINDS. TEMPERATURES ABOUT 5 DEGREES WARMER THAN 
YESTERDAY IN THE 30S...EXCEPT ACROSS THE TIP OF THE ARROWHEAD AND IN 
AREAS ACROSS THE SOUTH SHORE OF LAKE SUPERIOR WHICH EXPERIENCE LAKE 
EFFECT SNOW SHOWERS THIS MORNING WHERE TEMPS WILL ONLY WARM UP TO 
THE MID TO UPPER 20S.

TONIGHT...CLEARING SKIES. SLIGHTLY WARMER WITH THE LIGHT SOUTHERLY 
FLOW...BUT NOT BY MUCH AS HIGH PRESSURE BUILDS OVER MICHIGAN. LOWS 
IN THE SINGLE DIGITS IN THE MN ARROWHEAD AND INLAND NORTHWEST 
WISCONSIN TO TEENS ELSEWHERE.

SATURDAY...MOSTLY SUNNY AND MILD WITH INCREASING CLOUDS LATE IN THE 
DAY. A MID-LEVEL RIDGE MOVES ACROSS THE REGION AS A STRONG PRESSURE 
GRADIENT SETS UP OVER MINNESOTA DUE TO A DEEPENING LOW IN THE 
DAKOTAS AND HIGH PRESSURE OVER THE OHIO VALLEY. THIS SET UP WILL 
RESULT IN LOW/MID LEVEL WARM AIR ADVECTION WITH 850MB TEMPS CLIMBING 
FROM -10C TO -14C TO 0C TO -5C BY SATURDAY AFTERNOON. WINDS MAY 
BECOME BREEZY WITH MODEL SOUNDINGS INDICATING MIXING UP TO 850MB 
WHICH COULD CAUSE SOUTH/SOUTHWESTERLY WINDS OF 10 TO 20KTS AND PEAK 
GUSTS APPROACHING 30KTS. HIGHS IN THE MID TO UPPER 40S...EXCEPT 
ACROSS THE TIP OF THE ARROWHEAD WHERE TEMPS WILL BE LIMITED TO THE 
MID TO UPPER 30S.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 308 AM CDT FRI MAR 27 2015

THE PERIOD WILL FEATURE A FEW OPPORTUNITIES FOR PRECIPITATION WITH 
THE STRONGEST SYSTEM OCCURRING SATURDAY NIGHT INTO SUNDAY. THE 
MODELS ARE IN DECENT AGREEMENT EARLY THEN SHOW SOME SIGNIFICANT 
DIFFERENCES WITH A SHORTWAVE/LOW PRESSURE SYSTEM MONDAY/MONDAY NIGHT 
AND AGAIN AT THE END OF THE PERIOD.

STRONG WAA WILL DEVELOP SATURDAY NIGHT DUE TO A LLJ OF 40 TO 50 
KNOTS OCCURRING AHEAD OF A TROUGH OF LOW PRESSURE THAT WILL EXTEND 
SOUTH FROM THE MAIN LOW THAT WILL PASS NORTH OF THE REGION. A WINTRY 
MIX WILL LIKELY OCCUR AS WARMER TEMPS SURGE NORTH AS THE 
PRECIPITATION MOVES IN SATURDAY NIGHT. WE KEPT HIGH POPS SATURDAY 
NIGHT INTO SUNDAY MORNING...THEN THE MAIN AREA OF PRECIP SHOULD MOVE 
OFF SUNDAY AFTERNOON. ALTHOUGH A VARIETY OF PRECIP TYPES ARE 
POSSIBLE RANGING FROM RAIN TO SLEET AND PERHAPS A BRIEF PERIOD OF 
FREEZING RAIN...WE KEPT IT SIMPLE AT THIS TIME AND WENT WITH RAIN 
AND SNOW. PRECIP TYPE WILL BE A SHORTER TERM FORECAST PROBLEM. SOME 
LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE OVER FAR NORTHEAST 
MINNESOTA INTO PORTIONS OF NORTHWEST WISCONSIN. AT THIS TIME...IT 
LOOKS LIKE MOST AREAS WILL RECEIVE LESS THAN 2 INCHES. TEMPERATURES 
SHOULD WARM ENOUGH SUNDAY TO SWITCH THE PRECIP TO MAINLY RAIN FOR 
MOST AREAS. IT WILL BE WINDY AT TIMES SATURDAY NIGHT INTO SUNDAY 
NIGHT WITH SOUTHERLY WINDS SATURDAY NIGHT SWITCHING TO 
WEST/NORTHWEST WINDS ON SUNDAY.

ANOTHER WEAKER SYSTEM WILL MOVE IN MONDAY INTO MONDAY NIGHT. THE GFS 
AND ECMWF CONTINUE TO OFFER DIFFERENT SOLUTIONS WITH THE GFS SLOWER 
AND WEAKER. WE HAVE JUST SOME LOW POPS AT THIS TIME BUT MAY HAVE TO 
INCREASE ONCE BETTER AGREEMENT OCCURS. PRECIP TYPE MAY START OUT AS 
A MIX...SWITCH TO RAIN BEFORE GOING BACK TO SNOW MONDAY NIGHT. AT 
THIS TIME...ANY SNOWFALL LOOK TO BE LIGHT.

ANOTHER STRONGER LOW WILL IMPACT THE NORTHLAND WEDNESDAY INTO 
THURSDAY. MUCH UNCERTAINTY SURROUNDS THIS SYSTEM WITH QUITE A BIT OF 
MODEL UNCERTAINTY. ALTHOUGH BOTH THE GFS/ECMWF SHOW SIGNIFICANT 
DIFFERENCES...THEY BOTH BRING UP WARM ENOUGH AIR FOR MOSTLY RAIN 
WEDNESDAY. 

HIGHS THROUGH MUCH OF THE PERIOD WILL BE ABOVE NORMAL. 

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1208 PM CDT FRI MAR 27 2015

VFR EXPECTED THROUGH THE FORECAST WITH HIGH PRESSURE NEARBY.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  33  17  43  32 /   0   0   0  80 
INL  37  12  47  36 /   0   0   0  80 
BRD  36  17  45  36 /   0  10   0  80 
HYR  34   9  45  31 /   0   0   0  60 
ASX  31  12  45  32 /  40   0   0  50 

&&

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

$$

UPDATE...LE
SHORT TERM...JJM
LONG TERM...MELDE
AVIATION...GSF

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