Flash Flood Warning 1, NWS Boise, ID

Issued

Jun 21, 2002, 5:20 PM MDT (23:20 UTC)

Expired

Jun 21, 2002, 6:15 PM MDT

In force

55 min

Issued by

NWS Boise, ID

Area

Counties, with a storm outline in the text

Counties Boise County, ID, Valley County, ID

The Boise radar (KCBX), 132 km from the middle of the area, began a volume at 23:24 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

000 
WGUS55 KBOI 212320
FFWBOI
IDC015-085-220015-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BOISE ID
517 PM MDT FRI JUN 21 2002

THE NATIONAL WEATHER SERVICE IN BOISE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN BOISE COUNTY IN WEST CENTRAL IDAHO
  SOUTHEASTERN VALLEY COUNTY IN WEST CENTRAL IDAHO

* UNTIL 615 PM MDT

* AT 515 PM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY
  RAIN OVER CENTRAL VALLEY COUNTY...OR ABOUT 11 MILES SOUTH OF YELLOW
  PINE...MOVING NORTH AT 10 MPH.

CAMPGROUNDS IN THE LANDMARK AREA ARE IN THE PATH OF THIS STORM.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
BOISE.

LAT...LON 4470 11561 4406 11533 4413 11502 4492 11530

NWS Boise, ID wrote its last area forecast discussion before this flash flood warning went out at Jun 21, 2:32 PM MDT, 2 hours 48 minutes earlier.

SOUTHWEST IDAHO/SOUTHEAST OREGON AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE IDAHO
230 PM MDT FRIDAY JUNE 21 2002

AN ACTIVE CONVECTIVE EVENING SETTING UP OVER THE FORECAST AREA AS
PARAMETERS COME TOGETHER NICELY JUST AT THE RIGHT TIME OF DAY
STRONG SHORT WAVE ROTATING UP FROM SOUTHERN NEVADA WILL PROVIDE THE
DYNAMIC LIFT TO ORGANIZE STORMS. AIR MASS ALREADY VERY BUOYANT WITH
LIS DOWN TO -2 AND PWS QUITE HIGH AT NEAR ONE INCH.  FEEL PRIMARY
THREAT AT THIS TIME REMAINS LOCAL FLASH FLOODING FROM TRAINING
STORMS IN SLOW MOVING SOUTHERLY FLOW.  HAVE ALREADY ISSUED FLASH
FLOOD WATCH FOR EXTREME SW IDAHO COUNTIES AND MAY EXPAND TO FURTHER
ZONES IF CONDITIONS WARRANT BY 4PM.  SHEAR VALUES NOT ALL THAT
IMPRESSIVE IN KBOI CWFA AT THIS TIME BUT THEY ARE PRESENT FARTHER
NORTH OVER CENTRAL IDAHO MTNS AND KMSO FORECAST AREA.  RADAR
ESTIMATES ALREADY PICKING UP ON A FEW ONE INCH+ AMOUNTS OVER SW
IDAHO WITH STRONGER CELLS YET TO COME FROM NORTH CENTRAL NEVADA.
WILL INCLUDE BEEFED UP WORDING TO SEVERAL ZONES FOR LOCAL HEAVY RAIN
AND GUSTY WINDS ON EVENING PACKAGE. ACTIVITY MAY LAST FOR SEVERAL
HOURS THIS EVENING AND POSSIBLY AS LATE AS MIDNIGHT.  ACTION WINDS
DOWN OVERNIGHT BUT UNSTABLE AIR MASS CONTINUES FOR SATURDAY WITH
MORE SHOWERS AND THUNDERSTORMS OVER THE AREA INTO THE EARLY EVENING
HOURS.  WILL OPT TO DECREASE POPS GRADUALLY THROUGH THE PERIOD WITH
HIGHEST VALUES TONIGHT TAPERING OFF WEST TO EAST ON SATURDAY.  TEMPS
STAY VERY WARM WARM THROUGH THE WEEKEND WITH VERY LITTLE CHANGE DAY
TO DAY THROUGH MONDAY.

EXTENDED...LATEST MRF AND OTHERS SHOW LARGE UPPER RIDGE MOVING OVER
THE AREA NEXT WEEK AND INTENSIFYING BY MIDWEEK.  THIS SCENARIO WILL
PRODUCE A HOT DRY EXTENDED PERIOD OF WEATHER STARTING TUESDAY AND
LASTING INTO NEXT WEEKEND.  WITH HIGH HEIGHT CENTER APPROACHING 600,
SURFACE TEMPS WILL FLIRT WITH 100F ACROSS THE SNAKE PLAIN.

.BOI...FLASH FLOOD WATCH IN EFFECT FOR ID ZONES 15 AND 29 UNTIL
       MIDNIGHT.

G.SKARI

Flash Flood Warnings in Idaho, 2002Every flash flood warning in 2002

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.