FXUS65 KPIH 022046
AFDPIH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
146 PM MST WED DEC 2 2009

.SHORT TERM...THIS AFTERNOON THROUGH FRIDAY NIGHT...A COLD FRONT
PASSED THROUGH LAST NIGHT LEAVING NORTHERLY FLOW ALOFT AND COLD
CANADIAN AIR AT THE SURFACE. THIS WILL KEEP THE AREA DRY AND
COLDER THAN NORMAL THE NEXT THREE DAYS. SURFACE HIGH PRESSURE IS
EXPECTED TO BE CENTERED OVER THE UPPER SNAKE HIGHLANDS TONIGHT.
COMBINED WITH CLEAR SKIES...EXPECT LOWS NEAR OR SLIGHTLY BELOW
ZERO IN THE SNAKE RIVER PLAIN TONIGHT WITH LOWS -10 TO -20 IN THE
CENTRAL MOUNTAINS AND UPPER SNAKE HIGHLANDS. THURSDAY HIGHS WILL
BE IN THE MID TWENTIES IN THE SNAKE RIVER PLAIN AND IN THE LOW TO
MID TEENS IN HIGHER TERRAIN. TEMPERATURES WILL INCREASE 5 TO 10
DEGREES FRIDAY WITH HIGH PRESSURE RIDGING PRIOR TO THE NEXT SYSTEM
ON SATURDAY. WYATT

.LONG TERM...SATURDAY THROUGH WEDNESDAY. CANADIAN SYSTEM EXPECTED TO 
DROP SOUTHWARD ACROSS IDAHO ON SATURDAY.  MODELS CONTINUE TO DIFFER 
IN THE PLACEMENT AND EVOLUTION OF THIS SYSTEM...BUT SEEM TO BE 
COMING TO A BETTER CONSENSUS. PATTERN DOES POINT TO A RATHER COLD 
AND RELATIVELY DRY SYSTEM. LATEST RUNS ALSO INDICATE THAT THE SYSTEM 
WILL SPLIT...HOWEVER THE TIMING AND LOCATION OF THIS SPLIT DIFFERS.  
WILL KEEP TEMPERATURES UNSEASONABLY COLD WITH CHANCE POPS PRIMARILY 
IN THE HIGHER ELEVATIONS.  MODELS HINT AT A PATTERN CHANGE AROUND 
THE TUESDAY TIME FRAME ONCE THIS SYSTEM FINALLY HEADS TO THE EAST. 
THE GFS HAS COME IN LINE WITH THE ECMWFS IDEA OF A MOIST WEST TO 
SOUTHWEST FLOW TAPPING INTO SUBTROPICAL MOISTURE MIDWEEK.  HAVE 
UPPED POPS TO CHANCES ACROSS THE FORECAST AREA DURING THIS TIME 
FRAME.  HANKO

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THURSDAY NIGHT UNDER 
DRY NORTHERLY FLOW.  HANKO

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$