Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KDLH 010934
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
334 AM CST SUN FEB 1 2015

.SHORT TERM...(TODAY THROUGH MONDAY AFTERNOON)
ISSUED AT 328 AM CST SUN FEB 1 2015

MAIN SHORT TERM CONCERNS REMAIN FOCUSED AROUND THE LAKE EFFECT
SNOW SHOWERS CURRENTLY IMPACTING THE SOUTH SHORE OF LAKE SUPERIOR
FROM THE TWIN PORTS EAST TO AROUND BAYFIELD AND ASHLAND...AND THE
COLD TEMPERATURES ACROSS THE NORTHERN COUNTIES THIS MORNING AND
MORE WIDESPREAD COLD AIR OVERTAKING THE REGION TONIGHT/MONDAY
MORNING.

STRONG WINTER STORM CURRENTLY MOVING EWD ACROSS THE MID MS VALLEY
AND ERN OHIO VALLEY REGION THIS MORNING WITH AN E-W ORIENTED SFC
RIDGE BUILDING FROM NEAR WINNIPEG INTO WRN ONTARIO AND INTO NRN MN
AND THE WRN GREAT LAKES. THE POSITION OF THIS RIDGE AND THE
RESULTING NE LOW LEVEL WIND FLOW ACROSS WRN LAKE
SUPERIOR...COMBINED WITH STRONG CAA IN THE MID LEVELS HAS ALLOWED
A COUPLE LAKE EFFECT BANDS TO SET UP OVER THE WATER AND MOVE
INLAND ALONG THE SOUTH SHORE THIS MORNING. THE INITIAL BAND SET UP
LATE LAST EVENING ACROSS THE HEAD OF THE LAKE ALONG THE WRN SIDE
OF THE BAYFIELD PENINSULA AND TRACKED SLOWLY EWD INTO NRN DOUGLAS
COUNTY. AS MENTIONED IN THE PREVIOUS AFD THIS BAND LIKELY ENHANCED
ALONG A NARROW ZONE OF CONFLUENCE AIDED BY COLD AIR DRAINAGE ALONG
THE NORTH SHORE. THE LOW LEVEL FLOW HAS STEERED THIS BAND QUITE
FAR TO THE WEST TO AROUND SUPERIOR...WITH A FEW FLAKES EVEN
APPEARING AT THE NWS OFFICE AROUND 230 AM THIS MORNING. VISIBILITY
REPORTS IN AND AROUND THIS BAND HAVE BEEN POOR...AND AMTS HAVE
RANGED FROM 1 TO 3 INCHES.

NOT EXPECTING THIS WRN BAND TO MOVE TOO MUCH FURTHER TO THE WEST
INTO DULUTH AS THE LOW LEVEL WIND FLOW BACKS TO THE N/NW IN THE
NEXT COUPLE HOURS ACCORDING TO THE HIGH RES MODELS. SOME AREAS OF
DULUTH COULD SEE A QUICK HALF TO ONE INCH OF VERY FLUFFY SNOW THIS
MORNING BEFORE THE BAND SHIFTS BACK TO THE EAST. A SECONDARY BAND
TO THE EAST AROUND BAYFIELD AND ASHLAND HAS SET UP AS WELL...AND
HAS POINTED INTO THE BAYFIELD/WASHBURN AREA SINCE JUST AFTER
MIDNIGHT. HAVE NOT HAVE ANY REPORTS IN THIS AREA YET...BUT AMTS
WILL LIKELY BE SIMILAR.

CURRENTLY WE HAVE A LAKE EFFECT SNOW ADVISORY GOING FOR
DOUGLAS...BAYFIELD AND ASHLAND COUNTIES UNTIL NOON...AND AN
ADDITIONAL 1 TO 3 INCHES OF WIDESPREAD SNOW IS POSSIBLE...WITH
ISOLATED HIGHER AMTS IN THE PERSISTENT BANDS LIKELY. THERE IS SOME
QUESTION OF ADDITIONAL SIGNIFICANT ACCUMULATION IN ASHLAND COUNTY
WITH THE FLOW BEING MORE WRLY THIS MORNING...BUT WHEN THE FLOW
BECOMES MORE NRLY LATER...A PERIOD OF HEAVIER SNOW COULD MAKE ITS
WAY INTO THE NRN HALF OF THE COUNTY.

SO...WILL LEAVE THE AREAL COVERAGE AND TIMING OF THE LES ADVISORY
THE SAME FOR NOW AND MONITOR THE TRENDS IN THE RADAR AND ALSO THE
HIGH RES MODEL GUIDANCE FOR POSSIBLE CHANGES IN THE SNOW BANDS.

THE OTHER CONCERN THIS MORNING IS THE COLD AIR COVERING THE NRN
HALF OF THE NORTHLAND IN NE MN. SFC TEMPS HAVE FALLEN INTO THE
TEENS AND 20S BELOW ZERO THIS MORNING...WITH AN OCCASIONAL LIGHT
BREEZE PRODUCING WIND CHILLS IN 20 TO 25 DEG BELOW ZERO RANGE.
EVEN THOUGH THE ADVISORY IS BORDERLINE...WILL KEEP IT GOING UNTIL
11AM AT THIS TIME.

THE SFC HIGH WILL SETTLE IN OVER THE REGION TODAY AND TONIGHT AND
KEEP WEATHER CONDITIONS QUIET. THIS HIGH WILL ALSO ALLOW SKIES TO
CLEAR OUT AND ALLOW TEMPERATURES TO FALL ONCE AGAIN INTO THE TEENS
AND LOWER 20S BELOW ZERO. EXCEPT TONIGHT THE COLD AIR WILL BE MUCH
MORE WIDESPREAD. WINDS WILL BE GENERALLY LIGHT...BUT BREEZY AT
TIMES ALONG THE NORTH SHORE AND DROP WIND CHILLS INTO THE 20 TO 30
BELOW RANGE AT TIMES. MAY NEED ANOTHER WIND CHILL ADVISORY...BUT
WILL LET THE DAY SHIFT RE-EVALUATE CONDITIONS.

THE COLD NWLY FLOW WILL CONTINUE INTO TUESDAY WITH A WEAK SFC
TROUGH BRUSHING EWD ACROSS THE BORDERLAND. THIS WAVE WILL BE
FAIRLY BENIGN AND MAINLY ACT TO INCREASE THE CLOUD COVER...WITH A
FEW FLURRIES POSSIBLE OVER NE MN BY LATE TUE AFTERNOON.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 328 AM CST SUN FEB 1 2015

A RELATIVELY QUIET PERIOD IS EXPECTED FOR MUCH OF THE NORTHLAND WITH
THE EXCEPTION OF A LATE WEEK SYSTEM THAT COULD PRODUCE SOME LIGHT
SNOW ACCUMULATIONS WITH LAKE ENHANCEMENT POSSIBLE AS FAR WEST AS THE
TWIN PORTS.

A TROUGH OF LOW PRESSURE WILL MOVE THROUGH THE REGION MONDAY NIGHT
INTO TUESDAY AND MAY PRODUCE SOME FLURRIES AS IT MOVES THROUGH. A
WNW TO NW LOW LEVEL FLOW WILL COMBINE WITH COLD 850MB TEMPS TO CAUSE
LAKE SNOW SHOWERS ALONG PORTIONS OF THE SOUTH SHORE AS WELL. AT THIS
TIME...SIGNIFICANT SNOWFALL LOOKS UNLIKELY DUE TO FETCH LIMITATIONS.

A SHORTWAVE WILL MOVE THROUGH THE NORTHLAND TUESDAY NIGHT/WEDNESDAY
AND MAY BRING SOME LIGHT SNOW/FLURRIES TO PARTS OF THE NORTHLAND
WITH LITTLE ACCUMULATION. LAKE SNOW SHOWERS WILL CONTINUE TO BE
POSSIBLE...ESPECIALLY ALONG THE BAYFIELD PENINSULA AND INTO FAR
NORTHERN IRON COUNTY. A BETTER CHANCE FOR SOME ACCUMULATION WILL
OCCUR DURING THIS TIME AS FETCH TURNS A BIT MORE NORTHWEST AND THE
ECMWF HAS 850MB TEMPS DOWN TO -26C. HIGH PRESSURE WILL BE OVER THE
REGION WEDNESDAY...DROPPING SOUTHEAST THURSDAY. THE HIGH WILL CAUSE
LOW LEVEL WINDS TO BACK TO SOUTHWEST BY THURSDAY SHUTTING ANY LAKE
EFFECT OFF FOR A TIME.

THE MODELS OFFER DIVERGING SOLUTIONS FRIDAY INTO THE WEEKEND. THE
MAIN DIFFERENCE IS WHERE THE GFS/ECMWF EACH PUT THE SURFACE HIGH AND
SURFACE LOW. THE GFS IS FURTHER NORTH WITH THE LOW AND HAS MUCH
WARMER TEMPS OVER THE REGION. THE GFS ENSEMBLE MEMBERS SHOW A WIDE
SPREAD AND THE OPERATIONAL RUN OF THE GFS HAS SHOWN SOME SIGNIFICANT
CHANGES OVER THE PAST FEW RUNS. THE ECMWF IS MUCH COLDER WITH A
TIGHT BAROCLINIC ZONE OVER THE NORTHLAND. IT HAS ALSO BEEN MORE
PERSISTENT SHOWING LESS RUN TO RUN DIFFERENCES. WE FOLLOWED CLOSER
TO THE ECMWF AND HAVE A CHANCE FOR SNOW LATE IN THE WEEK INTO THE
WEEKEND. ALTHOUGH THIS SYSTEM DOES NOT LOOK LIKE A HEAVY SNOW
PRODUCER...THE ECMWF DOES SHOW LOW LEVEL WINDS TURNING
EAST/NORTHEAST FOR A TIME. THIS WOULD PROVIDE SOME SIGNIFICANT LAKE
ENHANCEMENT ALONG THE SOUTH SHORE POSSIBLY INTO THE TWIN PORTS
FRIDAY NIGHT/SATURDAY. THIS IS STILL A LONG WAY OUT THOUGH AND THERE
IS LOW CONFIDENCE AT THIS TIME ON THE DETAILS.

HIGH TEMPERATURES TUESDAY THROUGH THURSDAY WILL BE 5 TO 15 DEGREES
BELOW NORMAL WITH WEDNESDAY THE COLDEST DAY. TEMPERATURES WILL THEN
BE AROUND NORMAL LATE IN THE PERIOD. THERE MAY BE A NEED FOR SOME
WIND CHILL ADVISORIES WEDNESDAY NIGHT OVER NORTHERN PORTIONS OF THE
NORTHLAND.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1204 AM CST SAT JAN 31 2015

NOT MANY CHANGES WITH THIS FORECAST. HIGH PRESSURE WILL CONTINUE
TO BUILD ACROSS NORTHERN MINNESOTA DURING THE OVERNIGHT. HIGH
CLOUDS WILL DRIFT ACROSS ALL TERMINALS DURING THE OVERNIGHT...WITH
SOME LOWER CIGS EXPECTED IN NORTHWEST WISCONSIN IN RESPONSE TO
LAKE EFFECT SNOW. THERE HAVE BEEN TRANSIENT POCKETS OF MVFR CIGS
AT A FEW SITES IN CENTRAL MINNESOTA TONIGHT...BUT HAVE AVOIDED BRD
THUS FAR AND CONFIDENCE IS SUFFICIENTLY LOW TO STICK WITH
PREVAILING VFR CONDITIONS. A FAIRLY STRONG LAKE EFFECT SNOW BAND
HAS SET UP ALONG THE SOUTH SHORE OF LAKE SUPERIOR BETWEEN DLH AND
OLG. WHILE DECIDED TO GO WITH PREVAILING VCSH AT HYR AND DLH...DO
EXPECT MVFR CIGS/VSBYS AT OLG/SUW/DYT DURING THE OVERNIGHT PERIOD.
HAVE KEPT A TEMPO GROUP AT DLH FOR LIGHT SNOW WITH MVFR CIGS LATE
OVERNIGHT/EARLY MORNING IN THE EVENT THE SNOW BAND DRIFTS CLOSER
TO THE TERMINAL. SNOW WILL END DURING THE LATE MORNING ALONG THE
SOUTH SHORE...LEAVING HIGH PRESSURE AS THE MAIN WEATHER FEATURE
OVER THE AREA.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH   7  -7  13   4 /  10   0   0  10
INL   0 -18   9  -9 /   0   0  10  10
BRD   7  -5  15   6 /  10   0   0  10
HYR  10 -12  13   3 /  10   0   0  10
ASX   9  -4  14   6 /  60  10  10  10

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY UNTIL 11 AM CST THIS MORNING FOR MNZ010>012-
     018>021-026.

WI...LAKE EFFECT SNOW ADVISORY UNTIL NOON CST TODAY FOR WIZ001>003.

LS...NONE.
&&

$$

SHORT TERM...BJT
LONG TERM...MELDE
AVIATION...HUYCK





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.