FXUS65 KBOI 021028
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
328 AM MST WED DEC 2 2009

.SHORT TERM...NEW AIR MASS WHICH CAME IN FROM THE NORTH WEDNESDAY 
AFTERNOON IS COLDER AND DRIER THAN THE AIR MASS IT REPLACED.  
SAPIX...HOWEVER...STILL SHOW AREAS OF STRATOCUMULUS IN OUR SRN
ZONES EARLY THIS MORNING ALTHOUGH TENDING TO SHIFT TOWARD THE 
SOUTHWEST.  UNDER THESE CLOUDS TEMPS HAVE BEEN RELATIVELY HIGHER 
THAN IN THE CLEAR AREAS.  LATER TODAY THE CLOUDS SHOULD MOVE OUT 
AND THE COMING NIGHT WILL BE QUITE COLD DUE TO OUTWARD RADIATION 
UNDER CLEAR SKIES...LIGHTER WINDS...AND LOW HUMIDITY.  TOO DRY
FOR FOG THURSDAY MORNING EXCEPT POSSIBLY NEAR MYL...ONO...AND
ALONG THE SNAKE RIVER.  LITTLE CHANGE IN MAX TEMPS THURSDAY.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...SHORTWAVE RIDGE OVER 
THE AREA ON FRIDAY WILL BRING TEMPS BACK TO NEAR NORMAL. COLD FRONT 
PUSHES THROUGH THE AREA FRIDAY NIGHT AS UPPER LOW DROPS SOUTH OUT OF 
BC. LOW SETTLES OVER ID ON SATURDAY WITH NOTICEABLY COLD TEMPS 
/AROUND 10 DEGREES BELOW NORMAL/ AND A CHANCE OF SNOW SHOWERS ACROSS 
THE FORECAST AREA. WITH CONTINENTAL SOURCE PW/S ARE LOW SO EXPECT 
PRECIP AMOUNTS TO BE LIGHT. MODELS SHOWING LOW CENTER BECOMING 
ELONGATED E-W WITH AXIS STRETCHING ACROSS SOUTHERN ID THROUGH 
MONDAY. THIS WILL LOCK IN COLD AIR WITH VALLEYS STRUGGLING TO MAKE 
IT ABOVE FREEZING. BETTER AGREEMENT IN MODELS ON TIMING INJECTION OF 
MILD AND MOIST PACIFIC AIRMASS FOR NEXT TUE/WED.   

&&

.AVIATION...ISOLATED IFR IN MTN VALLEY FOG THIS MORNING. LOCAL MVFR 
CEILINGS IN STRATUS OVER SERN OREGON AND SWRN IDAHO SOUTH OF A 
KBNO-KBOI-KTWF LINE. CEILINGS WILL BREAK THIS AFTERNOON UNDER DRY 
NORTHERLY FLOW. VFR TONIGHT WITH ISOLATED MTN VALLEY FOG REFORMING.
LIGHT WINDS AT THE SURFACE WITH NORTHERLY WINDS ALOFT TO 30 KTS. 

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....DG
AVIATION.....DG