National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KDLH 070525
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1125 PM CST FRI DEC 6 2013

.UPDATE...
ISSUED AT 934 PM CST FRI DEC 6 2013

UPDATE TO LOWER TEMPS IN CASS.CROW WING...SRN ITASCA...AND AITKIN
COUNTIES BASED ON CURRENT TEMP/TD TRENDS 2-4 DEGREES. SOME AREAS
ARE ALREADY AT -20. WILL NOT UPGRADE AREA FOR WC WARNING AS
VALUES MAY TOUCH -40 BUT WILL FLUCTUATE BELOW THAT LEVEL. REST
OF FCST UNCHANGED.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 318 PM CST FRI DEC 6 2013

THE FOCUS IN THE SHORT TERM IS THE THREAT OF HAZARDOUS WIND CHILL
VALUES ACROSS THE NORTHLAND TONIGHT AND SATURDAY MORNING.

AT 315PM/2115Z...THE NORTHLAND WAS IN COLD W TO WNW LOW TO MID
LEVEL FLOW AS A STRONG LOW PRESSURE SYSTEM WAS MOVING FROM
SOUTHERN HUDSON BAY INTO QUEBEC. THE NORTHERN PLAINS AND UPPER
MIDWEST MAINLY HAD CLEAR SKIES WITH VERY COLD TEMPERATURES IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO. THERE WAS BKN/OVC SKIES OVER
PARTS OF WESTERN LAKE SUPERIOR AND THE BAYFIELD PENINSULA BECAUSE
THE VERY COLD WESTERLY FLOW WAS CAUSING LIGHT LAKE EFFECT SNOW
SHOWERS.

THE LATEST MODEL GUIDANCE GENERALLY CAME IN WITH COLDER
TEMPERATURES...ESPECIALLY FOR TONIGHT. I LEANED IN THE DIRECTION
OF THE COLDER GUIDANCE DUE TO THE CLEAR SKIES ACROSS AND FRESH
SNOWPACK ACROSS THE NORTHLAND. THE LIGHT WINDS WILL ALSO HELP
TEMPERATURES DROP TONIGHT. I EXTENDED THE WIND CHILL ADVISORIES IN
EFFECT ACROSS THE NORTHLAND TO NOON SATURDAY DUE TO THE COLDER
TEMPERATURES. WE MAY NEED TO CONSIDER A WIND CHILL WARNING FOR
PARTS OF THE WESTERN FORECAST AREA AS WIND CHILL VALUES IN THE
FORECAST FLIRT WITH 40 DEGREES BELOW ZERO WEST OF THE BRAINERD
AREA FOR A SHORT TIME OVERNIGHT.

THE LIGHT LAKE EFFECT SNOW OVER THE BAYFIELD PENINSULA COULD
CONTINUE THROUGH SATURDAY. THE MODELS SHOW LITTLE CHANGE IN THE
LAKE EFFECT THROUGH AT LEAST TOMORROW. THE WESTERLY DIRECTION
MAINLY MEANS ONLY FAR NORTHERN BAYFIELD COUNTY WILL BE AFFECTED.

I KEPT THE FORECAST CLEAR THROUGH AT LEAST THIS EVENING...BUT THE
BKN/OVC LAYER OF CLOUDS WELL NORTH OF THE MINNESOTA BORDER COULD
CREEP INTO NORTHERN MINNESOTA LATER TONIGHT AND SATURDAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 318 PM CST FRI DEC 6 2013

MAIN FOCUS DURING THE LONG TERM IS THE SUNDAY TO SUNDAY NIGHT
SNOWS...THEN ON A COUPLE CLIPPERS THAT MOVE THROUGH THE AREA DURING
THE WORKWEEK.  COLD TEMPERATURES CONTINUE...BUT THERE ARE A FEW
PERIODS OF WARMING.

SATURDAY NIGHT ANOTHER COLD NIGHT WITH THE SURFACE RIDGE SLOWLY
SHIFTING ACROSS THE AREA AND LIGHT WINDS.  HOWEVER...HIGHER UP
CLOUDS OUGHT TO BE STREAMING INTO THE AREA FROM THE
SOUTHWEST...WHICH WILL LIMIT RADIATIONAL COOLING SOME DESPITE THE
GOOD LOW LEVEL CONDITIONS.  THUS...HAVE GONE WITH THE COLDER MOS
GUIDANCE...GENERALLY FROM -20 TO AROUND ZERO.

SUNDAY AND SUNDAY NIGHT AN UPPER LOW THAT WILL HAVE BEEN
DEVELOPING OVER THE PLAINS WILL SWING ACROSS THE MIDWEST. THE
BULK OF THIS SYSTEM SHOULD BE SOUTHEAST OF THE FORECAST AREA...AND
WILL HAVE A BIGGER EFFECT ON SOUTHERN MINNESOTA AND SOUTHERN AND
CENTRAL WISCONSIN. A NICE BAND OF ISENTROPIC LIFT WITH SOME
RELATIVELY WEAK FRONTOGENESIS MOVES ACROSS THE SOUTHEAST PORTIONS
OF THE FORECAST AREA DURING THE AFTERNOON AND EVENING HOURS. HAVE
CONCERNS FOR DEEP LAYER SATURATION...THE DEPTH OF AIR THAT HAS TO
BE SATURATED IS QUITE DEEP AND WE MAY LOSE SOME INITIAL
PRECIPITATION TO SATURATING THE ATMOSPHERE. WITH AS COLD AN
AIRMASS WE HAVE I WOULD NORMALLY BE CONSIDERING A 20 TO 25 TO 1
SNOW WATER RATIO...BUT WITH THE DRY AIR CONCERNS HAVE KEPT IT DOWN
AROUND 18 TO 1. IF MOISTURE LOOKS BETTER...SNOWFALL AMOUNTS I HAVE
IN THERE NOW WILL NEED TO BE RAISED. AS IT IS HAVE AN EVENT TOTAL
FROM SUNDAY TO SUNDAY NIGHT OF 2 TO 4 INCHES ACROSS THE SOUTHEAST.
TEMPERATURES THROUGH THIS PERIOD WILL BE A LITTLE MILDER...BUT
STILL EXPECT HIGHS TO ONLY GET UP INTO THE 5 TO 15 ABOVE RANGE.

NEXT WEEK WE WILL STILL BE IN NORTHWEST FLOW ALOFT WITH A COUPLE
CLIPPERS DUE THROUGH THE AREA. FOR NOW THERE APPEARS TO BE ONE IN
THE MONDAY NIGHT-TUESDAY TIME RANGE...AND ANOTHER THURSDAY NIGHT-
FRIDAY. THE MONDAY NIGHT-TUESDAY ONE LOOKS FAST MOVING AND SHOULD
ONLY BRING LIGHT ACCUMULATIONS...BUT AT LEAST FOR NOW...THE ONE
LATER IN THE WEEK LOOKS A LITTLE STRONGER. SOME TIMING DIFFERENCES
THAT STILL NEED TO BE RESOLVED WITH THESE SYSTEMS...BUT HAVE KEPT
SOME SLIGHT TO LOW END CHANCE POPS IN THESE PERIODS FOR THESE
CLIPPERS. COLDER THAN NORMAL TEMPERATURES TO CONTINUE THROUGH THE
PERIOD...AND EXPECT THAT TEMPERATURES LATER IN THE WEEK WILL NEED
TO BE LOWERED WITH THE TENDENCY FOR GUIDANCE TO RAISE TEMPS
TOWARDS NORMAL FOR DAYS 5 THRU 7.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1125 PM CST FRI DEC 6 2013

VFR CONDITIONS ACROSS ALL TAF SITES THROUGH THE TIME PERIOD AS AN
AREA OF HIGH PRESSURE DOMINATES THE WEATHER. A OUTHWEST FLOW WILL
DEVELOP SATURDAY AFTERNOON WHICH COULD POSSIBLY CAOUSE SOME SCT
STRATUS TO FORM AND CONTINUE INTO SATURDAY EVENING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH -16   0 -12   9 /  10   0   0  60
INL -19  -3 -19   7 /  10  10   0  40
BRD -24  -2 -13   9 /   0   0  10  60
HYR -18   1 -12  11 /  10   0  10  80
ASX  -6   4  -6  13 /  10  10  10  70

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL NOON CST SATURDAY FOR MNZ010>012-
     018>021-025-026-033>038.

WI...WIND CHILL ADVISORY UNTIL NOON CST SATURDAY FOR WIZ001>004-
     006>009.

LS...SMALL CRAFT ADVISORY UNTIL 9 PM CST SATURDAY FOR LSZ146-147.

&&

$$

UPDATE...STEWART
SHORT TERM...GROCHOCINSKI
LONG TERM...LE
AVIATION...STEWART