Severe Thunderstorm Warning 48, NWS Pocatello, ID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO IDAHO
752 PM MDT SUN SEP 4 2005

.DISCUSSION...UPDATES WILL INCLUDE KEEPING ISOLATED THUNDERSTORMS IN
THE FORECAST UNTIL 300 AM MDT TONIGHT. SHOWERS CURRENTLY IN THE
CHALLIS AREA ARE SHOWING SIGNS OF STABILIZING IN RADAR IMAGERY BUT
WATER VAPOR IMAGERY ALSO SHOWS ONE MORE WAVE JUST CROSSING THE IDAHO
BORDER FROM OREGON AND THAT WAVE SHOULD TRACK THROUGH THE CHALLIS
AREA AS WELL. SIMILAR TO LAST NIGHT SATELLITE AND RADAR SHOWS
CONVERGENCE LINE VICINITY OF POCATELLO WITH CLOUD DEVELOPMENT
TRACKING ALONG IT FROM DIRECTION OF MALTA. OTHER ISOLATED CELLS IN
GETTING READY TO TRACK ACROSS BEAR LAKE. INSTABILITY LAST COUPLE
EVENINGS HAS BEEN RUNNING PAST MIDNIGHT SO A LITTLE PERSISTENCE MAY
NOT BE A BAD THING. CURRENT RED FLAG WARNING WILL EXPIRE AT 900 PM
MDT. A FEW MOUNTAIN SITES STILL MEETING GUST CRITERIA ESPECIALLY IN
THE UPPER SNAKE HIGHLANDS AND CARIBOU HIGHLAND AREAS WHERE ACTIVE
FIRES ARE BURNING BUT TREND IS DOWNWARD AND HUMIDITY STARTING TO
CLIMB. SURVICK

.PREV DISCUSSION...ISSUED 313 PM MDT SUN SEP 4 2005...UPPER TROF
WILL MOVE ACROSS MAINLY NRN ID OVERNIGHT. MINOR RIPPLES IN THE SW
FLOW OVER CEN AND ERN ID IS HELPING TO SET OFF A FEW TSTMS IN THE
CEN MTNS AND THE NE HIGHLANDS THIS AFTN.  THESE SHOULD DIE OUT THIS
EVENING AS THE MINOR TROFS MOVE EAST AND THE AIRMASS STABILIZES.

SW FLOW ALOFT REMAINS IN PLACE THRU WED.  UPPER RIDGE SHARPENS OVER
THE CWA AS A CLOSED LOW DEVELOPS OFF THE CA COAST...PER GFS.  THE
ETA PUTS THE CLOSED LOW OVER NRN CA FOR THE SAME TIME PERIOD...BUT
THIS SHOULD NOT MAKE A DIFFERENCE IN THE OUTCOME THRU WED. LOOKS TO
REMAIN DRY AND RELATIVELY WARM AT LEAST INTO EARLY WED. ETA BEING
RATHER AGGRESSIVE WITH PRECIP WED AFTN/EVE SINCE IT PUTS THE UPPER
LOW FARTHER EAST...WHERE THE GFS STAYS DRY. PREVIOUS FCST HAS PRECIP
OVER THE ERN AND SRN HIGHLANDS FOR THIS TIME PERIOD.  WILL LEAVE
THIS AS IS.

THE WEEKEND IS DOMINATED AGAIN WITH SW FLOW ALOFT...ALTHOUGH THE NEW
GFS RUN IS TRYING TO BRING A MAJOR SYSTEM INTO THE NW US BY LATE
SAT.  NOT READY TO BUY OFF ON THAT SCENARIO YET.  HEDGES

&&

.AVIATION...VFR CONDITIONS. ISOLD TSTMS NEAR THE CONTINENTAL DIVIDE
THIS EVENING MAY AFFECT TEWB ROUTES 340...343 AND 344 UNTIL 300 AM
MDT. ISOLD VISIBIILTIES REDUCED BY SMOKE FROM WILDFIRES ESPECIALLY
IN POCATELLO AREA.

&&

.PIH WATCHES/WARNING/ADVISORIES...RED FLAG WARNING FOR LOW RELATIVE
HUMIDITY AND GUSTY WINDS IN SOUTHEAST IDAHO FIRE WEATHER ZONES
405...406...407...409...410...411...412...AND 413 THROUGH 9PM MDT
SUNDAY NIGHT.  SEE LATEST BULLETIN FOR FURTHER INFORMATION.

&&

WEATHER INFORMATION ON-LINE 24-HOURS A DAY
(ALL LOWER-CASE LETTERS)

WWW.WEATHER.GOV/POCATELLO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE POCATELLO ID
445 AM MDT SUN 4 2005

IDZ017>025-031-032-051200-
LOST RIVER/PASHIMEROI-CACHE VALLEY/IDAHO PORTION-
SOUTH CENTRAL HIGHLANDS-WASATCH MOUNTAINS/IDAHO PORTION-
LOWER SNAKE RIVER PLAIN-SAWTOOTH MOUNTAINS-EASTERN MAGIC VALLEY-
BIG AND LITTLE WOOD RIVER REGION-UPPER SNAKE RIVER PLAIN-
CARIBOU HIGHLANDS-UPPER SNAKE HIGHLANDS-
445 AM MDT SUN SEP 4 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN IDAHO

.DAY ONE...
A TROUGH OF LOW PRESSURE OFF THE WEST COAST AND AN UPPER LEVEL
WEATHER DISTURBANCE WILL COMBINE TO PRODUCE ISOLATED MAINLY DRY
THUNDERSTORMS ACROSS THE REGION TODAY.  GUSTY WINDS TO 45 MPH ARE
EXPECTED NEAR STORMS.  THE PRESSURE GRADIENT WILL ALSO STRENGTHEN
WILL PRODUCE GUSTY WIND CONDITIONS BY THIS AFTERNOON OVER 25 MPH.
THE WIND...COMBINED WITH LOW RELATIVE HUMIDITIES HAS PROMPTED THE
ISSUANCE OF A RED FLAG WARNING...REFER TO THE LATEST BULLETIN FOR
ADDITIONAL DETAILS.

.DAYS TWO THROUGH SEVEN...
ANOTHER STORM SYSTEM IS SLATED FOR THE AREA LATE WEDNESDAY INTO
THURSDAY WITH A CHANCE OF THUNDERSTORMS...AND POSSIBLY MUCH COOLER
TEMPERATURES BY THURSDAY.  SNOW MAY FALL ABOVE 7000 FEET WITH THE
PASSAGE OF THIS STORM.  OUTDOOR ENTHUSIASTS SHOULD LISTEN TO NOAA
WEATHER RADIO OR LOCAL MEDIA FOR FURTHER UPDATES ON THE COLD AIR
POTENTIAL OF THIS STORM.

SPOTTER INFORMATION STATEMENT...
WE ASK ALL TRAINED SPOTTERS TO REPORT SIGNIFICANT WEATHER CONDITIONS.
THIS WOULD INCLUDE ALL HAIL...WIND...HEAVY RAIN AND FLOODING REPORTS.
THIS INFORMATION SHOULD BE CALLED INTO THE LOCAL NATIONAL WEATHER
SERVICE OFFICE IN POCATELLO USING THE 1-800 SEVERE WEATHER HOTLINE...
OR OTHER STANDARD OPERATING PROCEDURES.