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000
FXUS65 KPIH 042039
AFDPIH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
139 PM MST TUE MAR 4 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY.
UPPER LEVEL RIDGE MOVING THROUGH IDAHO THIS EVENING. EXPECT MAINLY
DRY CONDITIONS THROUGH WEDNESDAY MORNING WITH ONLY SOME VERY
SLIGHT CHANCE OF MOUNTAIN SHOWERS TONIGHT. RIDGE MOVES EAST
WEDNESDAY AFTERNOON AND EXPECT WARM FRONTAL OVERRUNNING
PRECIPITATION TO START IN CENTRAL MOUNTAINS AND UPPER SNAKE RIVER
HIGHLANDS. SNOW LEVELS WILL BE VERY HIGH WITH THIS SYSTEM RISING
TO ABOVE 7 THOUSAND FEET. PRECIPITATION WILL SPREAD EAST ACROSS
ALL OF SOUTHEAST IDAHO THURSDAY MORNING SPREADING THROUGH THE
SNAKE RIVER PLAIN AND SOUTHEAST HIGHLANDS BY EARLY AFTERNOON ON
THURSDAY. DO NOT THINK SNOW LEVELS WILL DROP BELOW 6500 FEET UNTIL
THURSDAY NIGHT UNTIL AFTER MOST PRECIPITATION HAS WEAKENED.
GENERALLY EXPECTING 4 INCHES AT AROUND 7 THOUSAND FEET TO UPWARDS
OF 8 INCHES ABOVE 8 THOUSAND FEET. EXPECT MAINLY RAIN UNDER 7
THOUSAND. NAM SNOW AMOUNTS IN THE CENTRAL MOUNTAINS REMAIN MUCH
HIGHER THAN THE GFS AND FOR NOW LEANING TOWARD GFS AMOUNTS. UPPER
TROF MOVES THROUGH IDAHO THURSDAY NIGHT AND MUCH COOLER AIR SHOULD
MOVE IN AND EXPECT INSTABILITY MOUNTAIN SNOW SHOWERS THURSDAY
NIGHT INTO FRIDAY WITH SNOW LEVELS AROUND 5500 FEET AND VERY LIGHT
ACCUMULATIONS POSSIBLE. NO WINTER WEATHER HIGHLIGHTS HAVE BEEN
ISSUED AT THIS TIME WITH EVENT START LIKELY 24 HOURS AWAY AND
WIDESPREAD WARNING AMOUNTS NOT EXPECTED. LOCALIZED FLOODING
POSSIBLE WITH THE VERY HIGH SNOW LEVELS EXPECTED AND LOW ELEVATION
RAINS.
GK

.LONG TERM... FRI NIGHT THROUGH NEXT TUE NIGHT. LONG WAVE INDICATES
A LOW AMPLITUDE PATTERN IN THE NORTHERN TIER OF THE COUNTRY. THIS
SHOULD MEAN A FORECAST CHARACTERIZED BY LOW CONFIDENCE AS MUCH OF
THE TIMING IS BASED ON SHORTWAVE ACTIVITY...WHICH CAN CHANGE TIMING
FROM NOT ONLY MODEL RUN TO MODEL RUN BUT ALSO BETWEEN GUIDANCE
SUITES. THE EARLY PART OF THIS PERIOD HAS THE BEST CONSISTENCY...BUT
DURING AND AFTER THE HANDLING OF THE MAJOR STORM FOR THIS PERIOD ON
MON...THE GUIDANCE PRODUCTS ARE NOT AGREEING. THE ECMWF BRINGS
ANOTHER WAVE CLOSE ON THE HEELS OF THE MON STORM...WHICH BOOSTS MON
POPS INTO THE LIKELY AND CATEGORICAL LEVELS FOR THE SOUTHERN HALF OF
THE FORECAST AREA. THE GFS HOLDS BACK THIS TROUGH AND BRINGS A DRIER
VERSION OF IT ON TUE/TUE NIGHT. HAVE TRIED TO COMPROMISE IN THIS
SECOND PART OF THE FORECAST BETWEEN SOLUTIONS. THE ONE THING
CONSISTENT IS THAT OVERNIGHT FREEZING TEMPERATURES FOLLOWED BY
MELTING AND TEMPERATURES GETTING TO NEAR NORMAL TO WARMER FOR THIS
TIME OF THE YEAR..WHICH IS MIDDLE 40S FOR THE SNAKE RIVER PLAIN.
THUS MUCH MORE MOUNTAIN SNOW AND RAIN AND SNOW FOR THE
HEAVILY-POPULATED AREAS. EXPECT BREEZY TO WINDY CONDITIONS WITH
THESE MON AND TUE FEATURES.  MESSICK

&&

.AVIATION...STRATUS SHOULD CLEAR WITH NO EXPECTED RETURN. THE MAIN
FORECAST WOULD BE STRATUS AND FOG WITH THIS CLEARING AND ALL THE
MOISTURE OF RECENT DAYS. BELIEVE THAT THE WINDS ABOVE THE SURFACE
ARE GENERATING ENOUGH TURBULENCE TO PREVENT ANY SERIOUS FOG. ONLY
THE GFS GUIDANCE FOR KIDA BRINGS IN IFR CIGS...THERE IS SOME 6000 FT
CLOUDS COMING IN ON THE NAM THAT WOULD HELP PREVENT THE STRATUS
DEVELOPMENT. SO HAVE LEFT IT OUT FOR THE COMING MORNING.  MESSICK

&&

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

$$