High Wind in Idaho, November 24, 2001

SOUTHWEST IDAHO/SOUTHEAST OREGON AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE IDAHO
155 PM MST SAT NOV 24 2001

MAJOR WINTER STORM DEEPENING OVER THE FORECAST AREA THIS EVENING
WITH VARIED PRECIP TYPES, STRONG WINDS AND EVEN THE POSSIBILITY OF
THUNDERSTORMS NEAR THE APEX OF THE DRY SLOT. SURFACE LOW CENTER
TRACKING AS MODELS FORECASTED, WITH STRONG PRESSURE FALLS INDICATED
ALONG THE OREGON/IDAHO BORDER.  LOW CENTER FORECAST TO BOTTOM OUT
OVER SOUTHWEST IDAHO THIS EVENING WHILE INTERSECTION OF WARM AND
COLD FRONTS, RAPIDLY OCCLUDES IN THE REGION. THIS SCENARIO DOES NOT
BRING THE FULL EFFECT OF THE WARM SECTOR INTO THE AREA BUT IN EFFECT
KEEPS MOST OF THE REGION ON THE COLD SIDE OF THE SYSTEM. THUS, EVEN
THE THREAT OF SNOW TO THE TREASURE AND MAGIC VALLEYS IS MORE LIKELY
NOW. WINDS HAVE INCREASED DRAMATICALLY IN THE LAST HOUR AND NOW ARE
HOLDING JUST BELOW ADVISORY CRITERIA. THIS IS THE EFFECT OF THE
EXPLOSIVE NATURE TO THE DEEPENING SURFACE LOW. EVEN THOUGH MAIN QPF
FIELDS ARE OVER CALIFORNIA AND THE GREAT BASIN, OUR REGION WILL ALSO
GETS ITS SHARE. SOUTH TO SOUTHWEST FETCH OF MOISTURE WITH STRONG
UPPER JET ENHANCEMENT WILL BE AN IDEAL SITUATION FOR HEAVY SNOW IN
THE UPSLOPE TERRAIN OF THE BOISE MOUNTAINS AND CAMAS PRAIRIE WHILE
OTHER MOUNTAIN ZONES GET IN ON THE ACT TOO THE FULL EFFECT OF THE
MAJOR SYNOPTIC EVENT WILL NOT BE FELT UNTIL SUNDAY EVENING DUE TO
THE WRAP AROUND NATURE OF THESE TYPE OF FEATURES WHERE STRONG WINDS,
AND COLD AIR SHOULD CAUSE NEAR WHITE OUT CONDITIONS OVER SOME
MOUNTAIN PASSES WITH ADDITIONAL ACCUMULATING SNOWS. WINDS EXPECTED
TO INCREASE INTO THE ADVISORY THRESHOLD ON SUNDAY(SOUTH-CENTRAL) AS
SYSTEM PASSES TO THE NORTHEAST AND DRAGS VERY WINDY CONDITIONS UNDER
STRONG PRESSURE GRADIENT ACROSS THE SNAKE RIVER VALLEY.  SUNDAY
NIGHT AND MONDAY TO FEATURE COLDEST AIR OF THE YOUNG SEASON UNDER A
FRESH SNOW COVER. WILL ALSO SEE CONTINUED SNOW SHOWERS MAINLY OVER
THE MOUNTAINS WHILE MOST AREAS GRADUALLY BEGINNING TO CLEAR OUT.
WILL GO WITH WINTER HIGHLIGHTS TONIGHT/SUNDAY FOR MOST ALL OF THE
REGION EXCEPT LOWER VALLEYS BUT THERE COULD EVEN BE A WINTRY
SCENARIO THERE TO BY MORNING.

EXTENDED...WILL GO WITH MRF SOLUTION OF COLD AND UNSETTLED THROUGH
THE PERIOD AS REGION DOES NOT RECOVER UNDER CYCLONIC FLOW. OPT FOR
SCATTERED SNOW SHOWERS IN THIS REGIME WITH THE POSSIBILITY OF RAIN
BY MIDWEEK AS WARMER AIR TRIES TO UNDERCUT COLD AIR AT THE SURFACE.
WILL NOT GET TO FANCY WITH THIS BECAUSE TIMING SMALL FEATURES WILL
BE DIFFICULT AT BEST.

G.SKARI

.BOI...HEAVY SNOW WARNING TONIGHT OREGON ZONES 61/62/ AND 63
       HEAVY SNOW WARNING TONIGHT IDAHO ZONES 11 13 28 29
       SNOW ADVISORY TONIGHT AND EARLY SUNDAY IDAHO ZONES 15 AND 30
       WIND ADVISORY FOR IDAHO ZONE 14 TILL 8PM THIS EVENING
       WIND ADVISORY SUNDAY FOR IDAHO ZONES 15 16 AND 30

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