000
FXUS63 KFGF 122130
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
330 PM CST THU DEC 12 2013

.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 330 PM CST THU DEC 12 2013

MAIN FORECAST CONCERNS IN THE SHORT TERM WILL BE EXTENT OF LIGHT
SNOW WITH PASSING UPPER WAVES AND TEMP TRENDS...WITH COLD AIR
REMAINING FIRMLY ENTRENCHED.

A NARROW BAND OF LIGHT SNOW HAS PROGRESSED FROM THE NORTHERN
VALLEY SOUTHEASTWARD INTO NW MINNESOTA THIS AFTERNOON. THIS WILL
CONTINUE TO SHIFT SOUTHEASTWARD THROUGH THE REST OF THE AFTERNOON.
ANOTHER AREA OF LIGHT SNOW WILL SHIFT INTO THE DEVILS LAKE BASIN
THIS EVENING AND SOUTHEASTWARD OVERNIGHT...IN ASSOCIATION WITH AN
AREA OF MID-LEVEL FRONTOGENESIS AND SYNOPTIC FORCING IN THE RIGHT
ENTRANCE REGION OF A BROAD UPPER JET. AS THE FORCING GRADUALLY
WEAKENS...A DECREASING TREND IN THE SNOWFALL IS EXPECTED WITH TIME
AS THE SNOW SHIFTS SOUTHWARD. RIGHT NOW THE BEST CHANCE FOR 1 TO 3
INCHES OF ACCUMULATION LOOKS TO BE FROM THE DEVILS LAKE AREA INTO
PARTS OF THE NORTHERN AND CENTRAL VALLEY TONIGHT INTO FRIDAY.
TEMPS TONIGHT MAY BE TRICKY. ALTHOUGH LOW-LEVEL COLD ADVECTION
WILL CONTINUE THROUGH THE NIGHT...HOW MUCH TEMPS FALL WILL DEPEND
ON CLOUD COVERAGE. THE RAP BRINGS SOME LOW-LEVEL DRYING INTO PARTS
OF NORTHWEST MINNESOTA OVERNIGHT. TEMPS COULD DROP PRETTY QUICKLY
IF ANY CLEARING DOES OCCUR...AND THUS HAVE THE LOWEST TEMPS IN
THIS AREA OF NW MINNESOTA. HIGHS ON FRIDAY LIKELY WILL BE COLDEST
NORTH...WITH TEMPS REMAINING BELOW ZERO...AND SINGLE DIGITS ABOVE
ZERO FARTHER SOUTH.

AS WINDS ARE EXPECTED TO STAY UP AROUND 10 KTS OVERNIGHT...WILL
ALSO ISSUE A WIND CHILL ADVISORY FOR MUCH OF NE ND EASTWARD INTO
NW MN FROM 06Z TONIGHT THROUGH 03Z SATURDAY. WITH WINDS BRISK FROM
THE NORTHEAST ON FRIDAY AHEAD OF THE SFC HIGH...HELD ONTO THE
ADVISORY UNTIL FRIDAY EVENING...ALTHOUGH WIND CHILLS MAY RISE ABOVE
CRITERIA FOR A BIT DURING THE DAY. AS THE SFC RIDGE AXIS
APPROACHES FRIDAY NIGHT...WINDS MAY GO LIGHT...ALLOWING FOR WIND
CHILLS TO RISE ABOVE ADVISORY THRESHOLD. THIS WILL BE MONITORED
DURING FUTURE SHIFTS THOUGH.

A SERIES OF UPPER IMPULSES EMBEDDED IN NORTHWEST FLOW ALOFT WILL
CONTINUE TO AFFECT THE AREA FRIDAY NIGHT INTO SATURDAY...BRINGING
CONTINUED CHANCES FOR LIGHT SNOW. ALTHOUGH MODEL QPF IS LOW...WITH
HIGH SNOW RATIOS AND MODEL SOUNDINGS INDICATING A FAIRLY DEEP
SATURATED LAYER...A FLUFFY INCH OR TWO OF SNOW IS
POSSIBLE...DEPENDING ON THE EXACT TRACK OF THE IMPULSES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 PM CST THU DEC 12 2013

TEMPS ON SATURDAY WILL RISE INTO THE SINGLE DIGITS EITHER SIDE OF
ZERO WITH LIGHT SNOW REMAINING POSSIBLE AS UPPER LEVEL ENERGY
CASCADES THROUGH THE FLOW. A SFC RIDGE WILL SPREAD OVER THE AREA
ON SATURDAY NIGHT. THE MAIN QUESTION WILL BE TEMPS...WHICH WILL BE
DEPENDENT ON CLOUD COVER. THUS...TEMPS COULD BE A BIT COLDER IF
SKIES DO CLEAR.

ANOTHER ROUND OF LIGHT SNOW IS POSSIBLE SUNDAY AS WARM AIR ADVECTION
DEVELOPS AND THE LOW-LEVEL BAROCLINIC ZONE APPROACHES FROM THE WEST
AHEAD OF THE NEXT UPPER WAVE. HOWEVER...TEMPS WILL REMAIN WELL
BELOW NORMAL.

FOR THE SUNDAY NIGHT THROUGH THURSDAY PERIOD...12Z ECMWF/GFS/GEM SO
ENOUGH DISAGREEMENT IN TIMING AND LOCATION OF SEVERAL 500 MB SHORT
WAVES/SURFACE LOW PRESSURE SYSTEMS TO KEEP CONFIDENCE IN FCST A BIT
LOWER THAN NORMAL.  IDEA IS FOR ONE SHORT WAVE MONDAY TO EXIT
FOLLOWED BY SOME COLDER AIR MON NIGHT-TUE  THEN THE NEXT ONE DUE WED
NIGHT-THU TIME FRAME.  EXACT PLACEMENT OF LOWS WILL MEAN POTENTIAL
TEMP DIFFERENCES WITH OVERALL 12Z EURO AND GEM A BIT WARMER THAN 12Z
GFS ESP FOR MID WEEK SYSTEM.  WITH THE DIFFERENCES STUCK WITH ALL
BLEND GUIDANCE. THERAFTER AND BEYOND THIS PERIOD IS WHEN THE NEXT
ARCTIC OUBREAK WILL OCCUR.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1245 PM CST THU DEC 12 2013

EXPECT MVFR-VFR CONDITIONS THRU THE PERIOD. MVFR CIGS INTO DVL
REGION AND EXPECT THE VFR CIGS ELSEWHERE TO GRADUALLY TURN MORE
MVFR OVERNIGHT INTO FRIDAY AS COLD FRONT SINKS SOUTH. SOME VERY
LIGHT SNOW WITH THIS FEATURE NRN VALLEY INTO FAR NW MN BUT VSBY
P6SM. A BIT BETTER CHANCE FOR SOME 3-5SM VSBYS IN -SN LATE TONIGHT
INTO FRIDAY WITH NEXT WAVE. WINDS WILL TURN TO A MORE NORTH-
NORTHEAST DIRECTION AT 10 TO 18 KTS TONIGHT AND FRIDAY.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 PM CST FRIDAY FOR
     NDZ006>008-014>016-024-026>030-054.

MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 PM CST FRIDAY FOR
     MNZ001-002-004>009-013>017-022-023.

&&

$$

SHORT TERM...MAKOWSKI
LONG TERM...RIDDLE
AVIATION...RIDDLE