Area Forecast Discussion
Issued by NWS Pocatello, ID

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

000
FXUS65 KPIH 131040
AFDPIH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
340 AM MST SAT FEB 13 2016

.SHORT TERM...TODAY THROUGH EARLY TUESDAY...MID TO UPPER LEVEL
MOISTURE PROVIDING MOSTLY CLOUDY OR CLOUDY SKIES EARLY THIS
MORNING WHICH WILL GIVE WAY TO PARTLY CLOUDY SKIES DUE TO DRIER
AIR FILTERING IN FROM THE WEST FOR MOST OF THE SNAKE PLAIN AND
SOUTHERN HIGHLANDS. AT THE SURFACE THIS DRY AIR EXPECTED TO
INCREASE WINDS IN EXCESS OF 20-25MPH WITH HIGHER GUSTS OUT OF THE
SW-W. MOSTLY CLOUDY SKIES ARE EXPECTED ACROSS THE CENTRAL
MOUNTAINS AND EASTERN HIGHLANDS WITH CHANCES OF SNOW ACCUMULATIONS
OF 1-2 INCHES TODAY.

OVERNIGHT TONIGHT THE BEGINNINGS OF A SERIES OF DISTURBANCES BEGIN TO
MOVE THROUGH OUR AREA...CREATING CHANCES FOR RAIN OR SNOW UNTIL
MONDAY. GREATEST LIKELIHOODS FOR SNOW EXPECTED IN THE CENTRAL
MOUNTAINS EARLY SUNDAY THROUGH MONDAY MORNING WITH 3-5 INCHES
FORECAST AND 6-7 INCHES POSSIBLE AT HIGHER ELEVATIONS. EASTERN
HIGHLAND AND UPPER SNAKE AREAS SHOULD ALSO EXPECT WIDESPREAD
SNOWFALL THROUGH MONDAY OF 4-6 INCHES WITH 7-10 INCHES AT HIGHER
ELEVATIONS. EXPECT PERIODS OF REDUCED VISIBILITY...WIND SPEEDS IN
EXCESS OF 20MPH AND BLOWING SNOW. VALLEY LOCATIONS HAVE A SLIGHT
POTENTIAL TO SEE SOME LIGHT SNOWFALL AT TIMES HOWEVER THIS SHOULD
MOSTLY BE A RAIN EVENT. ONCE AGAIN WINDS WILL BE INCREASING
THROUGH THE SNAKE PLAIN DURING THE DAY SUNDAY IN EXCESS OF 25MPH -
SHOULD NOT SEE BLOWING SNOW IN THESE AREAS.

BY LATE MONDAY...HIGH PRESSURE WILL BE BUILDING IN FROM THE
SOUTHWEST WITH ONLY LINGERING ACTIVITY EXPECTED IN OUR MOUNTAINOUS
AREAS. A RIDGE OF HIGH PRESSURE EXPECTED TO PROGRESS EASTWARD
GOING INTO TUESDAY WITH IMPROVING CONDITIONS. NP/DMH

.LONG TERM...TUESDAY THROUGH SATURDAY. MODELS IN GOOD AGREEMENT
EARLY IN THE PERIOD WITH SLOW PROGRESSION OF RIDGE AXIS EAST ACROSS
THE REGION. THUS TUESDAY AND WEDNESDAY APPEAR TO HAVE LITTLE IMPACT
WITH WARMER TEMPS AND DRY CONDITIONS. COULD SEE A RETURN OF SFC
BASED INVERSIONS WITH PATCHY FOG ESPECIALLY TUESDAY NIGHT. MODELS
BEGIN TO LOSE AGREEMENT WITH APPROACH OF SYSTEM EXPECTED FOR
THURSDAY. GFS ENSEMBLES STILL A BIT OF A JUMBLE WITH SOMEWHAT
SHALLOWER AND SLIGHTLY FASTER PROGRESSION OF OPEN TROUGH THAN
OPERATIONAL GFS AND EVEN SLOWER AND MORE AMPLIFIED ECMWF.
REGARDLESS...TIMING OF PRECIP STILL APPEARS TO BE WEDNESDAY NIGHT
INTO THE CENTRAL MOUNTAINS SPREADING RAPIDLY EAST ACROSS REMAINDER
OF FCST AREA ON THURSDAY. HAVE PUSHED POPS SLIGHTLY HIGHER FOR THIS
EVENT...EXPECTING RAIN/SNOW MIX IN LOWER ELEVATIONS ESPECIALLY
DURING THE DAY. COLD FRONT PASSAGE APPEARS TO BE MIDDAY THURSDAY AT
THIS TIME...AND HAVE TRENDED WINDS UP THOUGH STILL WELL BELOW GFS
GUIDANCE WHICH WOULD STRONGLY INDICATE POTENTIAL FOR WIND
EVENT/HEADLINE IN THE SNAKE PLAIN. ALL MODELS SHUFFLE PRECIP EAST BY
THURSDAY NIGHT WITH SOME SIGNS OF REDEVELOPMENT OF RIDGE OVER
PORTIONS OF THE WEST. ECMWF REMAINS THE MORE PROGRESSIVE
MODEL...SHOVING WEAKER RIDGE EAST AND BRINGING NEW SYSTEM INTO THE
REGION FRIDAY NIGHT/SATURDAY. GFS REMAINS MORE AMPLIFIED WITH RIDGE
WITH AXIS NEAR OR SLIGHTLY EAST OF FCST AREA AND ONSET OF NEXT
SYSTEM AFTER THIS OPERATIONAL PERIOD. GFS ENSEMBLES FAVOR THE GFS
SOLUTION...AND HAVE BLENDED SLIGHTLY DRIER INTO THE LATTER HALF OF
THE EXTENDED RANGE. DMH

&&

.AVIATION...FAST MOVING FEATURE DRIVES ACROSS EAST IDAHO TODAY.
REMNANTS OF SFC INVERSIONS REMAIN ALONG THE UT BORDER BUT SHOULD MIX
OUT TODAY AS SHORTWAVE DRIVES THROUGH. PRECIP SHOULD REMAIN FOCUSED
OVER HIGHER ELEVATIONS AND MAINLY NORTH SO EXPECTING NO IMPACT AT
TERMINAL SITES INCLUDING KSUN. WIDE DISPARITY IN MOISTURE CONTENT
BETWEEN MODELS AND BASED ON SATELLITE IMAGERY WILL LIKELY TREND
TOWARD VFR/MVFR FLIGHT CATEGORIES. WINDS COULD BE THE MAJOR PLAYER
TODAY FOR THE SNAKE PLAIN TERMINALS. GUIDANCE CONTINUES TO FLIRT
WITH THE 20-25KT RANGE AND WILL LIKELY NUDGE AFTERNOON WINDS TOWARD
THAT LEVEL. NEXT FAST MOVING FEATURE ALREADY APPROACHING COAST WITH
BETTER MOISTURE CONTENT. PRECIP EXPECTED TO DEVELOP AT KSUN BY
06Z...AND WILL LOWER CEILINGS TO MVFR/IFR IN SNOW. PRECIP SPREAD
COULD IMPACT SNAKE PLAIN TERMINALS KBYI/KPIH/KIDA BY 12Z WITH
ASSOCIATED DROP IN CEILINGS. DMH


&&

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

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.