000
FXUS63 KFGF 041841
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1241 PM CST WED DEC 4 2013

.UPDATE...
ISSUED AT 1241 PM CST WED DEC 4 2013

SEE LSR REPORTS FOR LATEST SNOWFALL TOTALS. THESE OBSERVATIONS ARE
MATCHING THE PREVIOUS UPDATE AND THE FORECAST APPEARS ON TRACK.
WIND SPEEDS ARE ALSO BEHAVING...AND GUIDANCE INDICATES SPEEDS
SHOULD NOT GET TOO MUCH HIGHER. SO...THE PREVIOUS UPDATE INDICATED
STORM TOTAL SNOWFALL OF 4 TO 8 ACROSS SOUTHEAST NORTH DAKOTA INTO
THE SOUTHERN VALLEY...WITH 6 TO 12 INCHES ACROSS THE REMAINDER OF
EASTERN NORTH DAKOTA INTO NORTHWESTERN MINNESOTA. REMEMBER...THESE
ARE TOTALS THAT INCLUDE TUESDAY INTO THURSDAY MORNING. ADDITIONAL
SNOWFALL (AFTER 18Z) SHOULD RANGE FROM 1 TO 3 INCHES WESTERN FA INTO
THE SOUTHERN VALLEY...3 TO 6 INCHES NORTHERN VALLEY TO PARK RAPIDS
AREA...AND 6 TO 9 INCHES NORTHWESTERN MN.

UPDATE ISSUED AT 1032 AM CST WED DEC 4 2013

12Z NAM HAS COME IN WITH HIGHER QPF TOTALS FROM 12Z WED TO 12Z
THUR...AND THE 15Z RAP MOSTLY AGREES. THESE MODELS APPEAR TO BE
PICKING UP ON MESO-SCALE FORCING THAT THE GFS/ECMWF/SREF/GEM ARE
NOT INCLUDING. CURRENT RADAR IMAGERY WOULD APPEAR TO INDICATE AND
AREA OF STRONGER FORCING FROM SE NORTH DAKOTA INTO NORTHWEST
MINNESOTA...WHICH THE NAM/RAP SHOW IN THEIR QPF FIELDS. SNOW
RATIOS ARE EXPECTED TO BE 15:1 TO 20:1...POSSIBLY HIGHER. USING
THE 12Z NAM QPF AND EXPECTED SNOW RATIOS...INDICATE 12Z WED-12Z
THU SNOW TOTALS OF 10-13 INCHES ACROSS NW MN...7-10 INCHES WC MN
INTO THE CENTRAL AND NORTHERN VALLEY...AND 4-7 INCHES SOUTHERN
VALLEY AND WEST OF THE VALLEY. AS WINDS INCREASE...THIS SHOULD AT
LEAST BREAK APART THE SNOWFLAKES AND DECREASE RATIOS A BIT...SO
WILL INCREASE SNOW TOTALS...BUT SOMEWHERE IN BETWEEN WHAT WE HAD
AND WHAT THE NAM INDICATES.

WILL ALSO NEED TO MONITOR WIND SPEEDS AND BLOWING SNOW POTENTIAL.
DID INCREASE WINDS A BIT BASED ON LATEST OBSERVATIONS COMPARED TO
THE GUIDANCE. AS TEMPERATURES GET COLDER THE SNOW WILL BE EASIER
TO BLOW AROUND...SO COULD BE CLOSE TO BLIZZARD CONDITIONS IN THE
MORE PRONE AREAS. HOWEVER...WIND SPEEDS NOT EXPECTED TO REACH
BLIZZARD CRITERIA (35 MPH)...SO THE WINTER STORM WARNING IS A VERY
GOOD PRODUCT.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 359 AM CST WED DEC 4 2013

WATER VAPOR LOOP INDICATED UPPER LEVEL TROUGH OVER THE PACIFIC
NORTHWEST WAS DIGGING AS JET MOVES DOWN WEST SIDE OF TROUGH. ALSO
UPPER LEVEL LOW NOTED OVER NORTHERN NV AND NORTHWEST SASK AND A
SHORT WAVE OVER SOUTHEAST MT. MT SHORT WAVE TO MOVE ACROSS THE
FORECAST AREA THIS AFTERNOON AND TONIGHT. PRECIPITABLE WATER WAS
UNDER HALF AN INCH AND IS FORECAST TO DECREASE TODAY AND TONIGHT.

THE MT SHORT WAVE WAS ESSENTIALLY AN OPEN WAVE AND CLOSES OFF AFTER
MOVING EAST OF THE AREA. INVERTED SURFACE TROUGH EXTENDS FROM
NORTHWEST MN INTO IA. INVERTED TROUGH TO SHIFT EAST TODAY. RADAR
SHOWED LIGHT SNOW ACROSS MUCH OF ND INTO ADJACENT PARTS OF MN AND
WAS MOVING NORTHEAST ABOUT 25 KNOTS.

INCREASED TEMPS COUPLE DEGREES FOR TODAY THROUGH FRI WITH CLOUD
COVER EXPECTED TO STAY AROUND. NO CHANGE TO THE WARNING. WILL KEEP
WARNING AS IS.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 359 AM CST WED DEC 4 2013

FOR SAT THROUGH TUE...IT LOOKS LIKE A VERY COLD PERIOD WITH HIGHS
NEAR OR BELOW ZERO...AND BITTERLY COLD OVERNIGHT LOWS. THERE WILL BE
A CHANCE FOR SOME LIGHT SNOW MAINLY SUNDAY INTO EARLY MONDAY...AHEAD
OF ANOTHER RE-ENFORCING ARCTIC FRONT AND COLDER AIR. NO MAJOR PRECIP
EVENTS EXPECTED THOUGH AS WE REMAIN DEEPLY ENTRENCHED IN ARCTIC AIR
THROUGH THE PERIOD...WITH DANGEROUS WIND CHILLS LIKELY AN ISSUE
ANYTIME THE WIND BLOWS SINCE IT WILL BE SO COLD.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1241 PM CST WED DEC 4 2013

GENERAL TREND WILL BE LIGHT TO MODERATE SNOW WITHIN AND EAST OF
THE VALLEY THROUGH MID AFTN. THIS WILL RESULT IN VSBY FLUCTUATIONS
FROM ABOUT 1/2SM TO 2SM...DEPENDING ON INTENSITY. WILL SEE THE
VALLEY IMPROVE FIRST FOLLOWED BY TVF/BJI IN THE LATE AFTN. CIGS
WILL PREDOMINANTLY REMAIN IFR WITH BREAKS INTO THE MVFR RANGE. BY
THE TIME CIGS IMPROVE...WINDS WILL KICK AROUND TO THE NW AND BLSN
COULD BE A PROBLEM OVERNIGHT. NOT CONFIDENT ENOUGH ON TIMING ANY
GIVEN SITE GOING BELOW 1SM...SO WILL HOLD OFF ON BLSN RELATED
VSBYS BEYOND THE FIRST SIX HOURS. CIGS WILL GRADUALLY CLIMB INTO
THE MVFR RANGE BY MORNING HOWEVER THE NW WINDS AND BLSN WILL
CONTINUE THROUGH 18Z THU.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER STORM WARNING UNTIL 6 AM CST THURSDAY FOR NDZ006>008-
     014>016-024-026>030-038-039-049-052>054.

MN...WINTER STORM WARNING UNTIL 6 AM CST THURSDAY FOR MNZ001>009-
     013>017-022>024-027>032-040.

&&

$$

UPDATE...TG
SHORT TERM...HOPPES
LONG TERM...DK
AVIATION...SPEICHER