000
FXUS63 KBIS 230852
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
252 AM CST MON NOV 23 2009

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...
THE LATEST WATER VAPOR IMAGERY SHOWS THE MAIN UPPER LEVEL LOW SPINNING
OUT OF EASTERN IDAHO AND INTO WESTERN WYOMING THIS MORNING. ANOTHER
CIRCULATION WAS SEEN ACROSS CENTRAL MONTANA AND MOVING EAST. A 110KT
JET STREAK OVER WESTERN IDAHO WILL CONTINUE TO DIG THE IDAHO/WYOMING
UPPER LOW SOUTHEAST AND DEVELOP IT FURTHER OVER COLORADO AND KANSAS
TODAY/TONIGHT. THIS KEEPS THE BEST DYNAMICS WELL SOUTH OF NORTH
DAKOTA. HOWEVER...MODELS ARE SHOWING THE AFOREMENTIONED UPPER
CIRCULATION OVER MONTANA SLIDING EAST ALONG THE NORTH AND SOUTH
DAKOTA BORDER TODAY/TONIGHT. PER GFS...A 700MB LOW DEVELOPS OVER
NORTHERN SOUTH DAKOTA THIS AFTERNOON AND MOVES NORTHEAST INTO
EASTERN NORTH DAKOTA THIS EVENING. ALL MODELS DEPICT AN AREA OF
PRECIPITATION OVER OUR FAR EASTERN AND SOUTHEASTERN ZONES
TODAY/TONIGHT. THIS ALSO COINCIDES ALONG AN INVERTED SURFACE
TROUGH STRETCHING FROM THE TEXAS/OKLAHOMA PANHANDLE INTO SOUTHEAST
NORTH DAKOTA. THE GFS INITIALIZED WELL WITH THE LATEST MSAS
ANALYSIS OF THE INVERTED TROUGH. THE LATEST FOG/STRATUS LOOP SHOWS
LOW/MID LEVEL CLOUDS MOVING INTO OUR FAR SOUTHEAST COUNTIES THIS
MORNING WITH RAIN OVER WESTERN MINNESOTA. THIS AREA OF PRECIPITATION
HAS BEEN SPREADING NORTHWEST WITH TIME. THE BUFKIT GFS SOUNDING
SHOWS A MIX OF RAIN/SNOW OVER JAMESTOWN AND VICINITY TODAY...THUS
WILL CONTINUE WITH A CHANCE OF PRECIPITATION IN THIS AREA. WILL
ALSO MAINTAIN A SLIGHT CHANCE NEAR/ALONG OUR SOUTHERN BORDER AND
INTO THE SOUTHWEST WHICH IS ALONG THE TRACK OF THE H5-H7 LOW.
CONDITIONS WILL REMAIN DRY BUT MOSTLY CLOUDY FURTHER NORTH.

TONIGHT INTO TUESDAY...THE UPPER LOW CONTINUES TO MOVE EAST AND SO
DOES THE INVERTED SURFACE TROUGH WHICH WILL RESULT IN PRECIPITATION
CHANCES DWINDLING IN THE FAR SOUTHEAST EARLY TONIGHT. WEAK RIDGING
PUSHES INTO OUR WESTERN AND CENTRAL ZONES LATER TONIGHT UNTIL 18Z
TUESDAY. BY 18Z TUESDAY...AN ALBERTA CLIPPER WILL BE APPROACHING
OUR NORTHWEST ZONES SPREADING CLOUDS FROM NORTHWEST TO SOUTHEAST
DURING THE DAY.

TUESDAY NIGHT INTO WEDNESDAY NIGHT...THE ALBERTA CLIPPER/COLD FRONT
WILL SWEEP THROUGH THE CWA BETWEEN 00Z AND 06Z WEDS. STRONG COLD
AIR ADVECTION ENSUES WITH BLUSTERY NORTHWEST WINDS BETWEEN 20 AND
35 MPH THROUGH WEDNESDAY EVENING. A SLIGHT CHANCE OF SNOW SHOWERS
IS WARRANTED WITH THE 850MB COLD POCKET/ISOTHERM TROUGH...AVAILABLE
LOW LEVEL MOISTURE...AND LAPSE RATES BETWEEN 8C AND 9C PER NAM
BUFKIT SOUNDINGS. WINDS SUBSIDE WEDNESDAY EVENING WITH SKIES
CLEARING WEDNESDAY NIGHT RESULTING IN COLD OVERNIGHT LOWS THURSDAY
MORNING...RANGING BETWEEN 15F AND 20F.


.LONG TERM...THURSDAY THROUGH MONDAY
MODELS CONTINUE TO DIVERGE LATE IN PERIOD AND WILL CONTINUE TO USE
ECMWF WHICH HAS VERIFIED BETTER LAST 6 DAYS.

THE 00 UTC ECMWF...GFS AND THEIR ENSEMBLES ARE IN GOOD AGREEMENT TO
START THE LONG TERM. BOTH MODELS AGREE IN HIGH AMPLITUDE 500 HPA
RIDGING IN PLACE ACROSS THE REGION THURSDAY THROUGH FRIDAY WITH
TEMPERATURES CONTINUING TO BE WELL ABOVE NORMAL FOR THIS TIME OF
YEAR.

BY SATURDAY THE MODELS BEGIN TO DISAGREE ON THE EVOLUTION OFF A
TROUGH MOVING FROM THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES.
BOTH MODELS SHOW A DEEP TROUGH EVOLVING LATE IN THE LONG TERM BUT
DIFFER SIGNIFICANTLY IN THE MOVEMNT OF A STRONG DISTURBANCE MOVING
THROUGH THE TROUGH WHICH HAS BIG IMPLICATIONS FOR WESTERN AND CENTRAL
NORTH DAKOTA. THE 00 UTC GFS MOVES THE DISTURBANCES FROM
SASKATCHEWAN INTO MANITOBA NORTH OF LAKE WINNEPEG BU SUNDAY EVEING
AND DEVELOPS A CLOSED LOW IN THIS AREA RESULTING IN LIGHTER
PRECIPITATION FOR WESTERN AND CENTRAL NORTH DAKOTA. THE 00 UTC ECMWF
TRACKS THIS DSITRUBACE ALONG THE INTERNATIONAL BORDER SATURDAY NIGHT
INTO SUNDAY CLOSING IT OFF DURING THE DAY ON SUNDAY. THE GFS IS ALSO
SLIGHTLY COOLER THAN THE ECMWF AT THIS STAGE.

&&

.AVIATION...
MID CLOUD MOVING NORTHWEST AS SURFACE LOW WELL SOUTH OF AREA DEEPENS
INVERTED TROUGH THROUGH EASTERN NORTH DAKOTA AND MINNESOTA. SLIGHT
CHANCE POPS EASTERN TAFS WITH MIX RAIN OR SNOW. ZERO TEMPERATURE DEW
POINT SPREAD IN FAR SOUTHEAST NORTH DAKOTA.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

KS/HW/DC