000
FXUS63 KBIS 102117
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
317 PM CST TUE DEC 10 2013

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 317 PM CST TUE DEC 10 2013

WEAK ALBERTA CLIPPER MOVING THROUGH THE SOUTH CENTRAL LATE TUESDAY
AFTERNOON PRODUCING SOME SNOW ACROSS THE SOUTHWEST/SOUTH CENTRAL.
ARCTIC HIGH MOVING INTO THE REGION TONIGHT CLEARING SKIES FROM NORTH
TO SOUTH. GUSTY WINDS OF 20 TO 35 MPH WILL CAUSE SOME BLOWING SNOW
THROUGH TUESDAY MID EVENING. THIS WILL BE FOLLOWED BY WIND CHILL
TEMPERATURES FALLING INTO THE ADVISORY RANGE OVER ALL OF THE WEST
AND CENTRAL. ALTHOUGH THE SOUTHWEST WILL SEE THE WIND CHILLS REACH
-25 AROUND OR SHORTLY AFTER MIDNIGHT WILL FOR SIMPLICITY ISSUE THE
WIND CHILL ADVISORY AS A SINGLE BLOCK FOR THE REGION BEGINNING
AT 6 PM AND CONTINUE THROUGH NOON WEDNESDAY. ANOTHER COLD NIGHT
FOR THE REGION WITH WEDNESDAY MORNING LOWS CLOSE TO 20 BELOW NORTH
CENTRAL TO 12 TO 15 BELOW SOUTH. WARM ADVECTION WEDNESDAY ACROSS
THE NORTH CENTRAL MAKES SOME CLOUDS...BUT AM SKEPTICAL ABOUT SNOW
SO REPLACED THE EARLIER CHANCE OF SNOW WITH FLURRIES NORTH
CENTRAL.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 317 PM CST TUE DEC 10 2013

THE MAIN FORECAST CHALLENGE IN THE LONG TERM PERIOD CONCERNS
DIFFICULTIES IN TIMING ARCTIC AIRMASSES/COLD FRONTS ARRIVING AND
EXITING THE STATE. THIS WILL RESULT IN LOW CONFIDENCE IN THE
TEMPERATURE FORECAST...WHICH DEPENDS GREATLY ON HOW DEEP AN ARCTIC
AIRMASS BECOMES ENTRENCHED OVER A SITE - OR HOW QUICKLY THE ARCTIC
AIR MOVES AWAY FROM A SPECIFIC LOCALE.

ON WEDNESDAY NIGHT LOW PRESSURE IS FORECAST TO BE IN THE LEE OF
THE ROCKIES OVER SOUTHERN ALBERTA/NORTH CENTRAL MONTANA...WITH AN
ARCTIC HIGH POSITIONED OVER THE YUKON AND NORTHERN ALBERTA. THE
ARCTIC HIGH MOVES SOUTHEAST ON THURSDAY AND REACHES THE NORTH
DAKOTA BORDER DURING THE AFTERNOON. THIS WILL ALLOW A NICE WARM-UP
THURSDAY. TEMPERATURES ON THURSDAY SHOULD BE MUCH MILDER WITH
HIGHS FROM 10 TO 20 ABOVE ZERO NORTH AND EAST OF THE MISSOURI
RIVER...AND 20 TO 30 ABOVE SOUTH AND WEST OF THE MISSOURI RIVER.
AS THE ARCTIC FRONT APPROACHES THE STATE FROM THE NORTH THIS WILL
INDUCE SOME LIGHT SNOW/FLURRIES ACROSS NORTHERN COUNTIES.

THIS ARCTIC COLD FRONT IS EXPECTED TO MOVE SOUTH ACROSS THE STATE
THURSDAY NIGHT...WITH THE BOUNDARY BETWEEN THE ARCTIC AIRMASS
REMAINING AT OR NEAR THE FAR SOUTHWEST CORNER OF NORTH DAKOTA ON
FRIDAY. MILDER AIR BEGINS PUSHING EASTWARD INTO SOUTHWESTERN NORTH
DAKOTA ON FRIDAY...WITH WARM ADVECTION CONTINUING FRIDAY NIGHT. THIS
WILL ALLOW A BRIEF WARM PERIOD AHEAD OF THE NEXT ARCTIC AIRMASS/COLD
FRONT THAT ARRIVES SATURDAY...AND EXITS THE STATE SUNDAY/SUNDAY
NIGHT. THERE WILL BE A PROLONGED PERIOD WITH A CHANCE OF LIGHT
SNOW/FLURRIES ACROSS THE FORECAST AREA THURSDAY THROUGH SATURDAY.
HIGH TEMPERATURES FRIDAY THROUGH SUNDAY SHOULD GENERALLY RANGE FROM
ZERO TO 5 BELOW ZERO IN THE NORTH CENTRAL/TURTLE MOUNTAINS TO THE
TEENS/20S ABOVE ZERO IN THE FAR SOUTHWEST.

SATURDAY`S ARCTIC AIRMASS IS FORECAST TO MOVE SOUTHEAST OUT OF THE
STATE SUNDAY/SUNDAY NIGHT WITH WARMER AIR MOVING IN FROM THE WEST
AND CHANCES OF LIGHT SNOW RETURN WITH A LOW PRESSURE CLIPPER-TYPE
SYSTEM THAT MOVES SOUTHEAST OUT OF SASKATCHEWAN SUNDAY NIGHT AND
MONDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 317 PM CST TUE DEC 10 2013

HAZARDS TO AVIATION INCLUDE SOME GUSTY NORTH WINDS OF 20 TO 30 KTS
THROUGH 02Z/8PM CST TUESDAY EVENING. THIS WILL CREATE SOME
BLOWING SNOW ACROSS THE WEST AND CENTRAL...BUT EXPECT VSBYS TO
REMAIN ABOVE IFR CATEGORY IN BLOWING SNOW. ARCTIC HIGH WILL PUSH
SOUTH INTO THE REGION BRINGING CLEARING SKIES AND VFR CONDITIONS
THROUGH THE 18Z TAF PERIOD.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 6 PM CST /5 PM MST/ THIS EVENING TO
NOON CST /11 AM MST/ WEDNESDAY FOR NDZ001>005-009>013-017>023-
025-031>037-040>048-050-051.

&&

$$

SHORT TERM...WAA
LONG TERM...JV
AVIATION...WAA