Tornado in Idaho, May 28, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO IDAHO
300 PM MDT SAT MAY 28 2005

.DISCUSSION...CUT OFF LOW IS MOVING INTO NORTHERN CALIFORNIA WITH
SWATH OF INSTABILITY AND THUNDERSTORMS ARCING INLAND AHEAD OF IT.
THERMAL TROUGH IS ALSO BEING NUDGED EAST AHEAD OF THIS LOW AND AREA
OF INSTABILITY EXPANDING INTO CASSIA COUNTY ROUGHLY SOUTH OF A LINE
FROM MALAD TO JEROME. ISOLATED THUNDERSTORMS DEVELOPING THIS AREA
SHOULD DISSIPATE AROUND 03Z. ALSO HAVE SPOKE OF ENERGY ROTATING
AROUND MANITOBA LOW THIS AFTERNOON AND EVENING. APPEARS TO BE SOME
BACK DOOR FRONTAL FORCING ALONG THE DIVIDE. NO LIGHTNING YET BUT
RADAR INDICATES A FEW CELLS DEVELOPING IN THE UPPER SNAKE HIGHLANDS
AS THE AREA FALLS UNDER CYCLONIC SIDE OF H7 DEFORMATION ALOFT.

GFS AND NAM IN GOOD AGREEMENT PLACING CENTER OF LOW OVER NORTHERN
CALIFORNIA THROUGH 12Z THEN BEGIN TO DIVERGE. GFS APPEARS TO HAVE
BETTER CONTINUITY AT THIS POINT TRACKING SLIGHTLY SOUTHEAST THROUGH
THE DAY BUT WITH SLOWER SPEED. NAM HAS CORRECTED MORE TOWARDS THE
GFS TRACK. BY 00Z RATHER SIGNIFICANT DIFFERENCES IN PLACEMENT OF H7
LOW...H7 WINDS AND THUNDERSTORM MOVEMENT. POPS IN GRIDS A BLEND OF
THE TWO MODELS SINCE LOCATION OF WRAP AROUND DIFFICULT TO PLACE AS
LOW MOVES EAST. LOT OF BOUNCING ON INSTABILITY PARAMETERS. GENERALLY
THINK SHEER WEEK ENOUGH TO PREVENT STRONG THUNDERSTORMS.
PRECIPITABLE WATER UP IN NAM AND GAVE BENEFIT OF DOUBT TO HIGHER QPF
WITH SLOWER CELL MOVEMENT.

FLATTER BUT PROGRESSIVE WESTERLY FLOW STILL THE TREND FOR THE MID TO
LATER PART OF THE WEEK. SIGNIFICANT SHORT WAVES WITH SHOWERS
EXPECTED WEDNESDAY AND AGAIN FRIDAY NIGHT AND SATURDAY. PATTERN
CHANGES TOWARDS LON WAVE TROUGH OVER EASTERN PACIFIC AND WEST COAST
BY END OF THE WEEK. RS

&&

.PIH WATCHES/WARNING/ADVISORIES...NONE.
&&

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

WWW.WEATHER.GOV/POCATELLO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE POCATELLO ID
540 AM MDT SAT MAY 28 2005

IDZ017>025-031-032-291200-
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-
540 AM MDT SAT MAY 28 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN IDAHO

.DAY ONE...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.  ISOLATED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE CENTRAL MOUNTAINS AND
UPPER SNAKE HIGHLANDS THIS AFTERNOON AND EVENING.  THESE STORMS ARE
EXPECTED TO PRODUCE ONLY LIGHT PRECIPITATION AMOUNTS.

.DAYS TWO THROUGH SEVEN...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

SPOTTER INFORMATION STATEMENT...
WE ASK ALL TRAINED SPOTTERS TO REPORT SIGNIFICANT WEATHER CONDITIONS.
THIS WOULD INCLUDE ALL HAIL...WIND...AND HEAVY RAIN AND SNOW
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.

MEYER