Severe Thunderstorm Warning 1, NWS Pocatello, ID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
1044 AM MDT WED MAY 28 2008

.UPDATE...HAVE ISSUED A FLASH FLOOD WATCH FOR THE CENTRAL
MOUNTAINS OF IDAHO THROUGH 10PM THIS EVENING. MORNING RAINFALL
TOTALS IN SOME AREAS WERE IN EXCESS OF ONE QUARTER OF AN INCH IN
90 MINUTES OR LESS...ESPECIALLY AROUND THE CASTLE ROCK FIRE AREA.
AM EXPECTING MORE SHOWERS/TSTORMS THIS AFTN WITH HEAVY RAINFALL
POSSIBLE. AM CONCERNED AS WELL ABOUT STRONG/SEVERE POTENTIAL THIS
AFTN WITH DRY SLOT WORKING INTO AREA. THIS IS ALLOWING FOR PLENTY
OF SUN AND INSTABILITY. ALSO BELIEVE SHEAR MAY BE STRONGER THAN
MODELS DEPICT DUE TO THINKING JET INFLUENCE WILL BE FARTHER WEST. EXPECTING
MAINLY HAIL THREAT AND HEAVY RAINFALL WITH STRONGEST ACTIVITY.
WILL CONTINUE TO MONITOR THIS THROUGHOUT THE DAY.  KEYES

&&

.PREV DISCUSSION... /ISSUED 230 AM MDT WED MAY 28 2008/

DISCUSSION...BROAD UPPER TROUGH NOTED ON SATELLITE IMAGERY ACROSS
THE WEST COAST EARLY THIS MORNING. A FAIRLY SIGNIFICANT VORT FEATURE
WAS NOTED LIFTING NE THROUGH ELY ON NOSE OF UPPER JET. VORT EXPECTED
TO SHIFT ACROSS SRN HALF OF FORECAST AREA THIS MORNING THEN NRN HALF
THIS AFTERNOON WITH ATTENDING SHOWERS/THUNDERSTORMS ACCOMPANYING
WAVE. MODELS SHOWING A COUPLE OF INGREDIENTS THAT MAY HELP TO
PRODUCE STRONG/ORGANIZED CONVECTION THIS AFTERNOON BUT
TIMING/POSITIONING OF ELEMENTS NOT WELL ALIGNED...WITH DECENT CAPE
VALUES FOCUSED ACROSS THE CNTRL MOUNTAIN ZONES AND 0-6KM SHEAR OVER
THE SE HIGHLANDS PER THE GFS WHEREAS THE NAM PLACED THE BEST CAPE
OVER THE SNAKE PLAINS CLOSER TO UPPER SHEAR ZONE. IF STORMS WERE TO
GET ORGANIZED...MAIN THREAT WOULD BE HAIL POTENTIALLY APPROACHING
SEVERE LEVELS. SHORT-WAVE ENERGY CONTINUES TO EJECT FROM THE COASTAL
LOW THROUGH THE WEEKEND AS UPSTREAM ENERGY DIGS INTO THE TROUGH FROM
THE PAC TO MAINTAIN SOME SEMBLANCE OF A MOIST AND UNSTABLE SW FLOW
ACROSS THE REGION WITH DIURNALLY FAVORED CONVECTION THROUGH SUNDAY.
SIZABLE CHUNK OF ENERGY ENTERS THE SYSTEM LATE SUNDAY AFTERNOON
SPINNING UP A CLOSED CIRCULATION WHICH DIGS SOUTH ALONG THE SIERRA
INTO CNTRL NEVADA EARLY NEXT WEEK WHICH EVENTUALLY LIFTS NE THROUGH
IDAHO WEDNESDAY FOR A HIGH PROBABILITY OF PRECIPITATION IF SCENARIO
PLAYS OUT. CONFIDENCE BETTER THAN AVERAGE WITH SIMILAR DEPICTION
NOTED ON THE ECMWF. STATISTICAL TEMPERATURE GUIDANCE PUSHES DAYTIME
HIGHS INTO CLIMATOLOGICAL RANGE (LOWER 70S IN SNAKE PLAIN) BY THE
WEEKEND AND THIS GENERALLY ACCEPTED AND FOLLOWED IN GRIDS. THE
HENRYS FORK NEAR REXBURG REMAINS ABOVE FLOOD STAGE WITH NO CHANGE
NEEDED TO PREVIOUSLY ISSUED STATEMENTS. HUSTON

AVIATION...MOIST SW FLOW FROM A CLOSED UPPER LOW OFF THE NRN CA
COAST CONTINUES. SHOWERS AND A FEW TSTMS WILL DEVELOP AGAIN THIS
AFTN. OCNL MVFR CIGS CAN BE EXPECTED IN THE TSTMS...OTHERWISE VFR
WILL BE THE PREVAILING CONDITION. HEDGES

FIRE WEATHER...A CLOSED UPPER LOW OFF THE CA COAST IS RESULTING IN
MOIST SW FLOW OVER ID FOR THE NEXT FEW DAYS. SHOWERS AND A FEW
AFTERNOON THUNDERSTORMS CAN BE EXPECTED AGAIN TODAY AND THURSDAY.
HUMIDITY READINGS WILL CONTINUE TO RUN ON THE HIGH SIDE DUE TO THE
MOIST AIRMASS AND WET GROUND. NO SIGNIFICANT FIRE WEATHER CONCERNS.
HEDGES

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 PM MDT THIS EVENING FOR IDZ018-031-
032.

FLOOD WARNING FOR HENRYS FORK OF THE SNAKE RIVER NEAR REXBURG
CONTINUES UNTIL FURTHER NOTICE.  &&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE POCATELLO ID
400 AM MDT WED MAY 28 2008

IDZ017>025-031-032-291200-
EASTERN MAGIC VALLEY-SAWTOOTH MOUNTAINS-UPPER SNAKE HIGHLANDS-
UPPER SNAKE RIVER PLAIN-LOWER SNAKE RIVER PLAIN-
SOUTH CENTRAL HIGHLANDS-CARIBOU HIGHLANDS-
CACHE VALLEY/IDAHO PORTION-WASATCH MOUNTAINS/IDAHO PORTION-
BIG AND LITTLE WOOD RIVER REGION-LOST RIVER/PAHSIMEROI-
400 AM MDT WED MAY 28 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN IDAHO.

.DAY ONE...TODAY AND TONIGHT

A FLOOD WARNING REMAINS IN EFFECT FOR THE HENRYS FORK AT REXBURG.
SHOWERS AND THUNDERSTORMS RETURN TODAY AS YET ANOTHER DISTURBANCE
LIFTS NORTHEAST ACROSS THE REGION. THERE ARE A COUPLE OF INGREDIENTS
THAT MAY HELP TO PROVIDE MORE STRENGTH AND ORGANIZATION TO
DEVELOPING STORMS TODAY...WHICH IN TURN MAY PRODUCE MODERATE SIZED
HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.  SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO BE A POSSIBILITY IN THE AFTERNOONS
AND EVENINGS.

.SPOTTER INFORMATION STATEMENT...

WE ASK TRAINED SPOTTERS AND CITIZENS TO REPORT SIGNIFICANT
WEATHER CONDITIONS WHEN IT IS SAFE TO DO SO. THESE CONDITIONS MAY
INCLUDE HAIL...TORNADOES...STRONG WIND...DUST STORMS...SNOWFALL...
EXTREME COLD TEMPERATURES...FREEZING RAIN OR HEAVY RAIN...DENSE
FOG...AND FLOODING OR ICE JAMS. INFORMATION ABOUT THESE HAZARDOUS
CONDITIONS SHOULD BE CALLED INTO YOUR NATIONAL WEATHER SERVICE
OFFICE IN POCATELLO USING THE 1-800 SEVERE WEATHER HOTLINE...OR
208-233-0834.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE POCATELLO/IDAHO FALLS ID
918 AM MDT WED MAY 28 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 AM     HEAVY RAIN       6 N HAILEY              43.60N 114.30W
05/28/2008  M0.40 INCH       BLAINE             ID   TRAINED SPOTTER

            1 HOUR ACCUMULATION

&&

TWYATT