Flash Flood Warning 1, NWS Boise, ID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
245 PM THU MAY 5 2005

.SHORT TERM...VERY MOIST PATTERN IS OVER THE FORECAST AREA FOR THE
NEXT TWO DAYS.  GOOD CONVECTIVE POTENTIAL THIS EVENING AS HEAD OF
DRY SLOT WORKS NORTH THRU NEVADA WITH BAND OF -3 LIS ACROSS
SOUTHERN IDAHO AND EXTREME SOUTHEAST OREGON. DO NOT EXPECT SEVERE
WITH THESE STORMS AS SHEAR REMAINS RATHER WEAK AND AIR ALOFT IS
WARM.  HOWEVER...MAIN THREAT APPEARS TO BE BRIEF HEAVY RAIN WITH PW
VALUES ABOVE 3/4 INCH. STORMS MOVING FROM SOUTH TO NORTH TENDING TO
TRAIN BUT THEY ARE MOVING NEAR 20 MPH SO FLASH FLOOD POTENTIAL NOT
THAT HIGH DESPITE GOOD RAIN PRODUCING EFFICIENCY TO CONVECTION. ON
FRIDAY SITUATION COULD BE EVEN BETTER WITH BETTER SYSTEM DYNAMICS
ARRIVING OVER THE AREA AS CLOSED LOW BEGINS TO OPEN UP AND MOVE
INLAND. THUS...MAY SEE BETTER STORM ORGANIZATION ON FRIDAY.  MODELS
NOT SHOWING THE BULK OF THE MOISTURE AND ASSOCIATED QPF COMING OVER
THE AREA FRIDAY NIGHT AND SATURDAY MORNING ALONG THE UPPER TROF AXIS
AND UNDER THE CLOSED LOW. THUS...AT THIS TIME WE MAY REALIZED THE
MOST BENEFICIAL RAINS AND PROLONGED PERIOD OF RAIN VERSUS SHOWERS
THAT WE ARE SEEING TODAY AND LIKELY TO SEE FRIDAY. SURFACE LOW
PRESSURE MOVES EAST FRIDAY NIGHT BRINGING A FRESHENING GRADIENT
ACROSS OREGON AND SOUTHWEST IDAHO FOR INCREASING WINDS WHILE AT THE
SAME TIME DIMINISHING THE CONVECTION THREAT FROM WEST TO EAST.
GOOD WEDGE OF DRIER AIR MOVES ACROSS THE REGION SUNDAY MORNING FOR
PARTLY CLOUDY SKIES AND SLIGHTLY COOLER TEMPS. TEMPERATURES TO STAY
NEAR NORMAL THROUGH THE PERIOD WITH A TENDENCY TO COOL A COUPLE
DEGREES OVER THE WEEKEND.

&&

LONG TERM...FOR SOUTHWEST IDAHO AND SOUTHEAST OREGON SUNDAY NIGHT
THROUGH THURSDAY. MODEL CONSISTENCY IS GOOD SHOWING ANOTHER UPPER
LEVEL TROUGH DROPPING INTO THE INTERMOUNTAIN REGION FROM OFF THE
NORTH PACIFIC COAST. THIS WILL CONTINUE CHANCE POPS AND COOL
TEMPERATURES ACROSS OUR CWA MONDAY AND TUESDAY. PRECIPITATION
CHANCES WILL FALL OFF WEDNESDAY AS THE TROUGH EXITS TO THE EAST. ON
THURSDAY A BUILDING UPPER LEVEL RIDGE WILL WARM MAX TEMPERATURES TO
NEAR NORMAL.

&&

.AVIATION...CONDITIONS WILL BE MAINLY VFR THROUGH FRIDAY WITH THE
EXCEPTION OF LOCAL MVFR CEILINGS IN AREAS OF LIGHT RAIN. THERE WILL
BE ISOLATED THUNDERSTORMS UNTIL ABOUT 06Z TONIGHT. AREAS OF RAIN
WITH MOUNTAIN OBSCURATION WILL CONTINUE THROUGH FRIDAY MORNING.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
.ID...NONE.
.OR...NONE.

WEATHER.GOV/BOISE

SHORT TERM...GS
AVIATION AND LONG TERM...JT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BOISE ID
518 AM MDT THU MAY 5 2005

IDZ011>016-028>030-ORZ061>064-061130-
WEST CENTRAL MOUNTAINS-LOWER TREASURE VALLEY ID-BOISE MOUNTAINS-
UPPER TREASURE VALLEY-SOUTHWEST HIGHLANDS-WESTERN MAGIC VALLEY-
CAMAS PRAIRIE-OWYHEE MOUNTAINS-SOUTHERN TWIN FALLS COUNTY-
HARNEY COUNTY-BAKER COUNTY-MALHEUR COUNTY-
LOWER TREASURE VALLEY OR-
418 AM PDT THU MAY 5 2005 /518 AM MDT THU MAY 5 2005/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
IDAHO...SOUTHWEST IDAHO...WEST CENTRAL IDAHO...SOUTHEAST OREGON
AND NORTHEAST OREGON.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER EXPECTED AT THIS TIME.