National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KPIH 190850
AFDPIH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
250 AM MDT SAT APR 19 2014

.SHORT TERM...TODAY THROUGH TUESDAY. UPPER LOW CIRCULATING IN THE
GULF OF ALASKA WILL SPIN OFF A SHORT WAVE INTO THE PAC NW TODAY.
MODELS SUGGESTING THIS MAY ENHANCE SURFACE CYCLOGENESIS OVER THE
SNAKE PLAIN WITH THE NAM ADVERTISING A STRONGER SURFACE GRADIENT
LATE TONIGHT INTO SUNDAY MORNING. GUIDANCE IS KEEPING WIND SPEEDS IN
THE LOW 20 KT RANGE PEAKING AROUND 15Z SUNDAY. WE THEN SEE A BRIEF
TRANSIENT RIDGE BUILD INTO THE AREA LEADING TO FAIR WEATHER.

THE UPPER RIDGE WILL SHIFT EASTWARD MONDAY AS ANOTHER SHORTWAVE
TROUGH SPINS INTO THE PAC NW. AS THE TROUGH ENTERS IDAHO...IT WILL
HAVE A NEGATIVE TILT AND WE SHOULD SEE SHOWERS SPREAD ACROSS THE
REGION LATE MONDAY NIGHT AND INTO TUESDAY. NOT ENOUGH CONFIDENCE IN
THE STRENGTH OF THE INSTABILITY TO INCLUDE THUNDER...BUT ENOUGH
MOISTURE TRANSPORT TO START INCREASING POPS LATE MONDAY NIGHT.
HINSBERGER

.LONG TERM...TUESDAY THROUGH SATURDAY NIGHT. MODELS STILL ON TRACK
WITH A DEEP UPPER TROF MOVING ONTO THE WESTERN US ON TUE. THIS
SYSTEM IS EXPECTED TO PRODUCE WIDESPREAD RAIN SHOWERS AND ISOLD
TSTMS ACROSS THE FCST AREA. SNOW LEVELS WILL BE AROUND 8000FT. AS
THE STORM SYSTEM MOVES OFF TO THE EAST...PRECIP CHANCES BEGIN
DIMINISHING IN THE VALLEYS ON WED BUT REMAIN HIGHER IN THE MTNS.
TEMPS WILL ALSO BE MUCH COOLER...WITH SNOW LEVELS DROPPING BELOW
5000FT. THUS MAY SEE SOME SNOW SHOWERS IN THE LOWER ELEVATIONS ON
WED. A STRONG POST FRONTAL PRESSURE GRADIENT WOULD INDICATE GUSTY
WINDS ON WED. UPPER RIDGING BUILDS IN FOR THU...RESULTING IN DRIER
CONDITIONS AND SLIGHTLY WARMER TEMPS THRU FRI. THE NEXT SYSTEM DUE
FOR THE WEEKEND IS HANDLED DIFFERENTLY BY THE MODELS. THE GFS IS
FASTER WITH THE UPPER TROF THAN THE ECMWF. WILL FAVOR THE ECMWF
SOLUTION AND ONLY GRADUALLY INCREASE PRECIP CHANCES SAT AND SAT
NIGHT. HEDGES
&&

.AVIATION...SHALLOW UPPER RIDGING TODAY WILL RESULT IN VFR
CONDITIONS THRU TONIGHT. HEDGES
&&

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

$$