Area Forecast Discussion
Issued by NWS Pocatello, ID

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 160332
AFDPIH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
832 PM MST MON DEC 15 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY. A QUICK UPDATE THIS EVENING
AS INITIAL WAVE OF LIGHT SNOWFALL LIFTING INTO SE IDAHO. MODELS
STILL SHOWING MAIN EVENT TO BE TUESDAY AFTERNOON AS WAVE POSITIONED
OVER CALIFORNIA LIFTS INTO SRN IDAHO. SEE PREVIOUS DISCUSSION BELOW.
HUSTON

A MEAN TROUGH POSITION NEAR THE WEST COAST WITH SOME QUICK MOVING
DISTURBANCES EMBEDDED IN THE WESTERLY WINDS UP STREAM. ONE
DISTURBANCE CROSSING CALIFORNIA AND NEVADA THIS AFTERNOON WILL LIFT
NORTHEAST TO IDAHO TONIGHT. USED A BLEND OF THE GFS AND NAM12 FOR
TIMING AND COVERAGE OF PRECIPITATION. EXPECT SOME LIGHT
PRECIPITATION TO ENTER THE SOUTH CENTRAL HIGHLANDS BY
MIDNIGHT...SPREADING QUICKLY OVER SOUTHEAST IDAHO TUESDAY MORNING.
BY WEDNESDAY MORNING SOME PRECIPITATION LINGERS IN THE UPPER SNAKE
HIGHLANDS AS THE DISTURBANCE MOVES EAST. AIR WILL BE COLD ENOUGH FOR
MOSTLY SNOW THIS TIME...SAVE TEMPERATURES REACHING 35 TO 40F TUESDAY
AFTERNOON ALONG THE I84/I86 CORRIDOR AND I15 NORTH TO IDAHO FALLS.
EXPECT UP TO AN INCH OF SNOW IN THE LOWER VALLEYS AND 1 TO 4 IN THE
MOUNTAINS THROUGH WEDNESDAY AFTERNOON. THE SECOND DISTURBANCE NEAR
134W SHOULD UNDERGO SOME SPLITTING AS IT REACHES THE COAST. THE GFS
BRINGS THE NORTHERN PORTION OF THE SPLIT THROUGH IDAHO ON THURSDAY
AT A PRETTY QUICK PACE FOR ANOTHER COUPLE INCHES IN THE MOUNTAINS
AND UP TO AN INCH IN THE LOWER VALLEYS. RS

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY. REGION WILL BE IMPACTED
BY A COUPLE WEAK UPPER TROUGHS AS WE HEAD INTO THE WEEKEND. THE
FIRST WILL BE EXITING IDAHO LATE THURSDAY WITH THE GFS BEING A BIT
SLOWER IN MOVING THAT SYSTEM AND ASSOCIATED PRECIP OUT OF THE AREA.
THE NEXT UPPER TROUGH WILL PASS THROUGH DURING THE DAY SATURDAY WITH
CONDITIONS BRIEFLY IMPROVING SATURDAY EVENING. TEMPERATURES SHOULD
REMAIN A FEW DEGREES ABOVE NORMAL THROUGH THE WEEKEND WITH THE GFS
SUGGESTING TEMPERATURES BACK IN THE UPPER 40S BY MONDAY. ECMWF HAS
COOLER TEMPERATURES FOR MONDAY. BOTH THE GFS AND ECMWF SUGGEST
SOUTHWARD SHIFT IN THE JET ALLOWING A MOIST ZONAL FLOW TO BE SET UP
OVER THE AREA STARTING SUNDAY NIGHT. UPSLOPE PRECIP WILL BE FAVORED
OVER THE CENTRAL MOUNTAINS AND EASTERN HIGHLANDS.  HINSBERGER
&&

.AVIATION...UPPER RIDGING WILL BEGIN SHIFTING EASTWARD TONIGHT. NAM
IS FASTEST IN BRINGING PRECIP TO SOUTHEAST IDAHO OVERNIGHT
ASSOCIATED WITH NEXT UPPER DISTURBANCE. GUIDANCE AND FORECAST
SOUNDINGS SUGGEST IMPACTS WITH MVFR/IFR CONDITIONS. GFS TIMING IS
APPROXIMATELY 2 TO 3 HOURS BEHIND THE NAM. SNOW AMOUNTS ARE EXPECTED
TO BE ABOUT A HALF INCH IN THE SNAKE PLAIN AND UP TO AN INCH AT KSUN
WITH SNOW EXPECTED TO CONTINUE FALLING THROUGH TOMORROW EVENING IN
THE CENTRAL MOUNTAINS. HINSBERGER
&&

.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.