559
FXUS63 KBIS 162018
AFDBIS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
318 PM CDT WED OCT 16 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 318 PM CDT WED OCT 16 2013
COLD FRONT PUSHING THROUGH NORTH DAKOTA THIS AFTERNOON WITH POST
FRONTAL PRECIPITATION MOVING SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN
AND NORTHEAST MONTANA. SHORT TERM MODELS REMAIN IN GOOD AGREEMENT
AND WILL UTILIZE A MODEL BLEND WITH PERSISTENCE FOR MOST FORECAST
ELEMENTS. DID USE THE SLIGHTLY WARMER RAW GUIDANCE FOR MINIMUM
TEMPERATURES WITH MAINLY CLOUDY SKIES AND BREEZIER CONDITIONS.
WITH THE WARMER TEMPERATURES...FROZEN PRECIPITATION WAS LIMITED TO
THE HIGHER ELEVATIONS OF THE FAR SOUTHWEST LATE THIS EVENING AND
OVERNIGHT. LITTLE IF ANY ACCUMULATIONS ARE EXPECTED. SYSTEM EXITS
THE SOUTHEAST ON THURSDAY WITH SUBSIDENCE DRYING THINGS OUT FROM
NORTH TO SOUTH DIRECTLY BEHIND THE POST FRONTAL PRECIPITATION
BAND. MOISTURE INCREASES AGAIN THROUGH THE AFTERNOON AND WITH
STEEP LAPSE RATES...WE COULD SEE A FEW RAIN OR SNOW SHOWERS. AT
THIS TIME KEPT ANY PRECIPITATION MENTION CONFINED TO THE NORTHWEST
AND FAR SOUTHWEST...CLOSEST TO THE DEEPEST MOISTURE ALOFT. QUITE A
BIT COOLER ON THURSDAY WITH HIGHS MAINLY IN THE 40S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 318 PM CDT WED OCT 16 2013
THE LONG TERM PERIOD BEGINS WITH A LONGWAVE TROUGH EXTENDING FROM
NORTH CENTRAL CANADA AND HUDSON BAY...THROUGH THE DAKOTAS. A
SECONDARY COLD FRONT IS PROGGED TO MOVE SOUTHEASTWARD ACROSS NORTH
DAKOTA THURSDAY NIGHT...WITH COLD ADVECTION CONTINUING ON FRIDAY
WITH NORTHWESTERLY WINDS LINKED FROM THE SURFACE TO ABOVE H800.
EXPECTING NORTHWEST WINDS TO INCREASE FRIDAY TO 15 TO 25 MPH OVER
EASTERN PORTIONS OF CENTRAL NORTH DAKOTA...TO 25 TO 35 MPH NORTHWEST
WINDS OVER THE WESTERN PART OF THE STATE. A H250 NORTHERLY UPPER
LEVEL JET OF AROUND 100 KNOTS IS PROGGED OVER WESTERN NORTH
DAKOTA...AND THE HIGHER ELEVATIONS OF THE SOUTHWEST WILL LIKELY SEE
THE HIGHER END OF THE 25 TO 35 MPH RANGES.
UPPER LEVEL ENERGY IMPULSES MOVING THROUGH THE FLOW...ALONG WITH THE
SURFACE COLD FRONT...WILL KEEP CHANCES OF RAIN OR SNOW SHOWERS IN
THE FORECAST THURSDAY NIGHT AND FRIDAY. LOOKING AT LOWS THURSDAY
NIGHT IN THE LOWER 30S...HIGHS FRIDAY IN THE 40S...AND LOWS FRIDAY
NIGHT FROM THE MID 20S TO LOWER 30S.
ON SATURDAY...ANOTHER SHOT OF COLD AIR MOVES INTO THE REGION BEHIND
ANOTHER COLD FRONT. THIS WILL BE ANOTHER DAY OF GUSTY NORTH WEST
WINDS...BUT WINDS ARE NOT EXPECTED TO BE AS STRONG - BUT STILL 15 TO
25 MPH. AGAIN LOOKING AT HIGHS IN THE 40S. ANOTHER SHOT OF A CHANCE
OF RAIN OR SNOW WITH AN UPPER LEVEL IMPULSE ALONG AND BEHIND THE
COLD FRONT.
NORTHERLY FLOW CONTINUES THROUGH MID-WEEK...WITH A HIGHLY AMPLIFIED
RIDGE OVER THE WEST COAST AND TROUGH OVER EASTERN NORTH AMERICA.
HIGHS MAINLY IN THE 40S...AND LOWS FROM THE MID 20S TO LOWER 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 318 PM CDT WED OCT 16 2013
COLD FRONT WILL MOVE SOUTH THROUGH THE AREA TODAY AND TONIGHT WITH
A BAND OF LOW VFR TO AND OCCASIONAL MVFR CEILINGS WITH SCATTERED RAIN
SHOWERS EXPECTED BEHIND THE FRONT. BEST PRECIPITATION CHANCES
REMAIN OVER THE SOUTHWEST SO ADDED A MENTION OF -RA AT KDIK AROUND
MIDNIGHT. OTHERWISE COVERED AERODROMES WITH VCSH FOR NOW. COLDER
AIR LOOKS TO PRODUCE A MIX OF RAIN AND SNOW MAINLY OVER THE FAR
SOUTHWEST AT THIS TIME SO NO MENTION OF SNOW IN AERODROMES AT THIS
TIME. LATEST 18Z SHORT RANGE CONSENSUS MODEL HAS BUMPED UP POPS
ACROSS THE AREA SO MAY NEED TO ADD A PERIOD OF PRECIPITATION AT
KMOT KBIS AND KJMS WITH THE 00Z TAF UPDATE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM...JV
AVIATION...TWH