Debris Flow and Flooding in Idaho, March 30 to 31, 2011

Name: Debris Flow and Flooding in Idaho, March 30 to 31, 2011
Start: 2011-03-30T11:00
End: 2011-03-31T23:59
Location: Idaho

March 30 to 31, 2011 · NWS OTX · 6 events in 5 counties and zones

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $1.8 million
Crop damage: None recorded
Events: 6

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS OTX wrote it up.

A stationary trough of low pressure off the Pacific Northwest Coast steered a deep fetch of subtropical moisture into the Idaho Panhandle which persisted from March 29th through early April. This resulted in several rounds of moderate to heavy precipitation, which primarily fell as rain below 6000 feet. Mild temperatures and breezy winds accompanying the subtropical moisture feed resulted in excessive mid-elevation snowmelt. The combination of heavy rainfall and excessive snow melt resulted in sharp rises in most basins within the Central Idaho Panhandle and Idaho Palouse. In addition, saturated soils became unstable in some locations resulting in debris flows.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Spokane, WA wrote its last area forecast discussion before the first event at Mar 30, 3:30 AM PST, 7 hours 30 minutes earlier.

Area forecast discussion, Mar 30, 3:30 AM PST, 7 hours 30 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
430 AM PDT WED MAR 30 2011

.SYNOPSIS...
WINDY CONDITIONS WILL DEVELOP TODAY AFTER A ROUND OF RAIN IN THE
MORNING. THE UNSETTLED...WINDY AND AND OCCASIONALLY SHOWERY
REGIME WILL CONTINUE THROUGH THURSDAY...WITH A BREAK PERIOD ON
FRIDAY. A NEW STORM SYSTEM WILL BRING MOUNTAIN SNOW AND VALLEY
RAIN ON SATURDAY...WITH UNSETTLED CONDITIONS REMAINING TROUGH
THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
TODAY THROUGH THURSDAY....SATELLITE REVEALS A FLAT AND VERY MOIST
ZONAL FLOW REGIME DESCENDING INTO THE REGION THIS MORNING. A WARM
FRONT IS PASSING THROUGH THE FORECAST AREA THIS MORNING WITH
STRATIFORM RAIN OVER THE EASTERN THIRD OF THE FORECAST AREA...AND
A WELL DEFINED RAIN SHADOW FEATURE EVIDENT ON RADAR...INDICATIVE
OF FAST WESTERLY FLOW IN THE MID LEVELS.

LATEST MODELS ARE IN RELATIVELY GOOD AGREEMENT IN FORECASTING A
RELATIVELY STATIC FAST WESTERLY FLOW REGIME ACROSS THE
FORECAST AREA TODAY THROUGH THURSDAY. A STRONG...LONG...AND WELL
DIRECTED FETCH OF SUBTROPICAL MOISTURE WILL CONTINUE TO FETCH INTO
THE REGION...BOBBLING A BIT NORTH OF THE FORECAST AREA TODAY AS
THE MAIN WARM FRONT FEATURE MOVES OUT OF THE FORECAST AREA TO THE
NORTHEAST THIS MORNING. THIS WILL LEAD TO A DECREASE IN RAIN THIS
MORNING OVER THE EASTERN BASIN...BUT MAINTAIN DENSE SHOWER
ACTIVITY ACROSS THE CASCADE CREST AND THE IDAHO PANHANDLE
MOUNTAINS. THE WARM FRONT IS EFFECTIVELY LOFTING FREEZING LEVELS
UP INTO THE 5000 FOOT RANGE THIS MORNING...WHERE IT WILL REMAIN
FOR THE NEXT 48 HOURS AT LEAST. THUS...SNOW ACCUMULATIONS SHOULD
BE CONFINED ONLY ON THE HIGHER PEAKS AND RIDGES...WITH MAYBE SOME
SLUSH ON THE HIGHER PASSES...WITH ALL RAIN BELOW 4000 FEET OR SO.

AS THE RAIN DECREASES OVER THE BASIN TODAY...WIND WILL BECOME THE
DOMINANT HARASSING WEATHER ELEMENT. THERE ARE TWO ISSUES IN
PLAY...ONE IS A RELATIVELY WEAK SURFACE LOW PRESSURE SCOOTING
ACROSS SOUTHERN CANADA AND DEEPENING IN THE LEE OF THE ROCKIES
THIS AFTERNOON...WHICH WILL PROMOTE A TIGHTENING SOUTHWESTERLY
GRADIENT ACROSS THE FORECAST AREA. THIS GRADIENT WILL BE
MODERATELY STRONG AND ENOUGH TO PROMOTE SUSTAINED WINDS INT HE 20
TO 30 MPH RANGE ESPECIALLY OVER THE EXPOSED TERRAIN...BUT THE MAIN
ISSUE WILL BE THE GUST POTENTIAL THIS AFTERNOON AND EVENING AS
VERY SWIFT WINDS JUST ABOVE THE BOUNDARY LAYER BEGIN TO RANDOMLY
TRANSLATE TO THE SURFACE DURING AFTERNOON MIXING. A POTENTIALLY
GREATER THREAT WILL BE STRONG WINDS RIPPING ACROSS THE CASCADE
CREST DOWN SLOPING INTO THE DEEP BASIN TODAY. THUS THERE ARE TWO
DISTINCT WIND THREAT REGIMES TO DEAL WITH. THE FIRST...ACROSS THE
EASTERN BASIN INCLUDING THE L-C VALLEY AND CAMAS PRAIRIE WILL BE
SUSTAINED 20 TO 30 MPH SOUTHWEST WINDS WITH GUSTS TO 40 OR 50
MPH...MOST COMMON ON THE MORE EXPOSED TERRAIN AND HIGHER BENCHES
AROUND THE REGION SUCH AS THE WEST PLAINS...ALPOWA SUMMIT AREA AND
THE PALOUSE. THERE IS HIGH CONFIDENCE THAT THE CURRENT WIND
ADVISORIES WILL ADEQUATELY COVER THIS POTENTIAL.

THE SECOND REGIME WILL BE THE DOWNSLOPE THREAT IN THE DEEP BASIN
FROM MOSES LAKE TO LEAVENWORTH. SUSTAINED WINDS WILL BE
SIMILAR...BUT THERE IS A THREAT OF VERY STRONG GUSTS RANDOMLY
STRIKING THE SURFACE MAINLY IN THE VANTAGE-DESERT AIRE AREAS AND
THE HIGHER BENCHES AROUND WENATCHEE. SUBSEQUENT SHIFTS WILL NEED
TO CAREFULLY MONITOR THIS POTENTIAL...IF THESE FREAK GUSTS BECOME
FREQUENT OR DENSE...THEN THE CURRENT ADVISORY MAY NEED TO BE
UPGRADED TO A HIGH WIND WARNING.

THE VERY WELL MIXED REGIME WILL LEAD TO VERY MILD HIGH
TEMPERATURES TODAY...ALTHOUGH FORECAST HIGHS FOR ANY LOCATION ARE
BALLPARK ESTIMATES BASED ON ADIABATIC COMPRESSIONAL WARMING OF
850 MB TEMPERATURES BROUGHT DOWN TO THE SURFACE...AND MAY NOT BE
ACHIEVED ON A WIDESPREAD BASIS GIVEN THE RANDOM MOMENTUM MIXING
REGIME.

TONIGHT A PARTIAL DE-COUPLING IS EXPECTED...ENOUGH TO MINIMIZE
THE STRONG GUST POTENTIAL BUT NOT A GENERAL BREEZY GRADIENT WIND
WHICH WILL KEEP OVERNIGHT LOWS ELEVATED AND ON THE MILD SIDE.
MEANWHILE THE MOIST ZONAL FLOW WILL MAINTAIN DENSE SHOWERS IN THE
MOUNTAINS OVERNIGHT.

ON THURSDAY LITTLE CHANGE TO THE PATTERN IS EXPECTED...EXCEPT THE
DEEP PACIFIC MOISTURE FETCH WILL MORE DIRECTLY HOSE THE
REGION...LEADING TO THE LIKELIHOOD OF THE MOUNTAIN SHOWERS OVER
THE PANHANDLE BACK-FILLING INTO THE EASTERN BASIN FOR A GENERAL
INCREASE IN RAIN CHANCES EAST OF A LINE FROM OMAK TO WALLA WALLA.
WINDS WILL CONTINUE TO BE BREEZY AND GUSTY ON THURSDAY. /FUGAZZI

THURSDAY NIGHT THROUGH TUESDAY...THE JET STREAM REMAINS ANCHORED
NEAR THE CANADIAN BORDER...CONTINUING TO STEER SYSTEMS ACROSS THE
INLAND NORTHWEST. THERE REMAINS A FAIR AMOUNT OF MODEL SPREAD WITH
REGARD TO THE TIMING OF THESE SYSTEMS...WHICH IS NOT TOO SURPRISING
AS IT IS OFTEN DIFFICULT IN THE FAST WESTERLY FLOW. THE FORECAST
LEANS TOWARD THE GFS WHICH HAS A MORE RUN-TO-RUN CONSISTENCY AND
SOME SUPPORT FROM THE NAM...AT LEAST EARLY ON. IN ADDITION...THROUGH
THIS PERIOD THE WESTERLY FLOW WILL KEEP PRECIPITATION CHANCES
LOWER IN THE LEE OF THE CASCADES/DEEPER BASIN AND SECONDARILY OVER
L-C VALLEY DUE TO SOME DOWN SLOPING.

ON THURSDAY NIGHT INTO FRIDAY A COLD FRONT DROPS TOWARD THE OR/WA
BORDER AND STALLS...WHILE SOME DRIER AIR FILTERS IN. THIS WILL
PUSH THE PRIMARY PRECIPITATION CHANCES TO THE EASTERN
MOUNTAINS...FAR SOUTHEAST ZONES AND BACKED AGAINST THE CASCADE
CREST.  SNOW LEVELS LOWER INTO FRIDAY MORNING. SOME DISAGREEMENT
EXISTS OVER HOW MUCH THEY WILL FALL. THE FORECAST LEANS TO THE
GFS. THIS MEANS SNOW LEVELS AVERAGING BETWEEN 2-4KFT...WITH THE
LOWEST TOWARD THE NORTH/NORTHWEST CWA. BREEZY TO LOCALLY WINDY
CONDITIONS WILL CONTINUE THURSDAY EVENING...BEFORE GRADIENTS
SLACKEN AND MIXING ABATES GOING INTO THE OVERNIGHT AND
FRIDAY...AND WINDS BECOME LIGHTER.

FROM FRIDAY NIGHT THROUGH SUNDAY THE NEXT SYSTEM MAKES ITS WAY
THROUGH THE REGION. AS INDICATED EARLIER THERE IS MODEL SPREAD
WITH REGARD TO THE TIMING AND RUN-TO-RUN CONSISTENCY HAS BEEN FAIR
TO POOR...ESPECIALLY WITH THE ECMWF. THE EVOLUTION OF THIS SYSTEM
WILL BE FINE-TUNED AS MORE INFORMATION COMES IN. LOOSE AGREEMENT
HOWEVER SHOWS A WARM FRONT...WITH DEEPENING MOISTURE AND
ISENTROPIC LIFT INCREASING PRECIPITATION CHANCES ACROSS THE REGION
FRIDAY NIGHT. THE TRAILING COLD FRONT OCCLUDES AND COMES THROUGH
SOMETIME BETWEEN EARLY MORNING AND EARLY AFTERNOON SATURDAY...WITH
A SECONDARY SURFACE LOW DEVELOPING ALONG IT AND AN INVERTED
SURFACE TROUGH NOSING INTO THE EASTERN THIRD OF WA/NRN ID. THESE
LATTER FEATURES WILL PROVIDE AN ADDITIONAL FOCUS FOR PRECIPITATION
DEVELOPMENT THROUGH SATURDAY...WITH THE THREAT SHIFTING TOWARD THE
NORTHEAST WA AND IDAHO MOUNTAIN ZONES BY LATE AFTERNOON INTO
SATURDAY NIGHT. THE PRECIPITATION RISK WILL FURTHER DECLINE GOING
INTO SUNDAY AS THE SYSTEM BEGINS TO MOVE EAST AND SHORT-WAVE
RIDGING COME IN.

AVERAGE SNOW LEVELS WILL BE BETWEEN 2-4KFT OVER THE NORTHWEST
TWO-THIRDS OF THE CWA AND BETWEEN 4-6KFT OVER THE SOUTHEAST CWA
THROUGH SATURDAY...BEFORE FALLING TO BETWEEN 1-3KFT
OVERNIGHT...AND RECOVERING TO BETWEEN 3-4KFT SUNDAY AFTERNOON.
THIS WILL SUPPORT PRIMARILY VALLEY RAIN AND MOUNTAIN SNOW (THOUGH
SOME MIX IS POSSIBLE CLOSER TO THE CASCADES) THROUGH SATURDAY.
THIS WILL CHANGE TO A POSSIBLE RAIN/SNOW MIX OR SNOW IN THE
EASTERN VALLEYS SATURDAY NIGHT AND SUNDAY...THOUGH ACCUMULATIONS
IF ANY LOOK MINOR.

ALONG WITH THE PRECIPITATION THREAT ON SATURDAY...BREEZY
CONDITIONS ARE EXPECTED. AT THIS TIME WINDS ARE PROJECTED TO BE
REMAIN BELOW ADVISORY LEVELS. HOWEVER WE WILL HAVE TO MONITOR
AREAS FROM THE LEE OF THE CASCADES...NEAR WENATCHEE INTO THE
DEEPER BASIN WHICH WILL BE MORE MARGINAL.

BETWEEN MONDAY AND TUESDAY THE NEXT SYSTEM MOVES DOWN THE PACIFIC
COAST. AT THIS TIME MOST GUIDANCE SHOWS THE LEADING WARM FRONT AND
OVERRUNNING PRECIPITATION THREAT SLIPPING IN FROM THE WEST AND
NORTHWEST LATE MONDAY AFTERNOON TO MONDAY NIGHT. THE TRAILING COLD
FRONT SLIDES BY EARLY TO MIDDAY TUESDAY...SHIFTING THE PRECIPITATION
FOCUS AGAIN TOWARD THE PANHANDLE AND FAR SOUTHEAST CWA. AT THIS
TIME MEAN SNOW LEVELS LAY BETWEEN 4-5KFT ON MONDAY...RAISING TO
BETWEEN 5-6KFT OVER THE DEEPER BASIN/SOUTHEAST CWA AHEAD OF THE
COLD FRONT MONDAY NIGHT AND TUESDAY...BEFORE DROPPING AGAIN TO
BETWEEN 1-3KFT TUESDAY NIGHT (INTO WEDNESDAY MORNING). THE DETAILS
OF THIS SYSTEM...LIKE THE PREVIOUS...WILL CONTINUE TO BE FINE-TUNED
AS MODELS COME INTO BETTER AGREEMENT. /JCOTE

&&

.AVIATION...
12Z TAFS...AN ILL DEFINED WARM FRONT...MAINLY IN THE MID LEVELS...IS
MOVING NORTHEAST THROUGH THE REGION THIS MORNING. A VERY MOIST
PACIFIC FETCH IS ENHANCING INTO WIDESPREAD RAIN EAST OF A LINE
FROM KOMK TO KLWS. MVFR CEILINGS WILL BE COMMON DURING THIS
STRATIFORM EVENT OVER THE EASTERN TAF SITES...WITH OCCASIONAL IFR
CEILINGS POSSIBLE AT KGEG AND KPUW THROUGH 18Z. THIS PRECIPITATION
WILL GRADUALLY MOVE OUT OF THE BASIN BY 18Z...REPLACED BY A MOIST
ZONAL FLOW WHICH WILL MAINTAIN DENSE RAIN AND HIGH MOUNTAIN SNOW
SHOWERS NEAR THE CASCADE CREST AND THE MOUNTAINS OF THE IDAHO
PANHANDLE...WITH SCATTERED SHOWERS OVER THE EASTERN BASIN
DECREASING IN DENSITY TO ISOLATED IN THE DEEP COLUMBIA BASIN NEAR
THE CASCADES.

A MODERATELY STRONG PRESSURE GRADIENT AND VERY STRONG MID LEVEL
FLOW ACROSS THE REGION WILL PROMOTE VERY WINDY AND GUSTY
CONDITIONS AT ALL TAF SITES THIS AFTERNOON AND EARLY
EVENING...WITH THE POTENTIAL FOR STRONG WESTERLY GUSTS LASTING
WELL INTO TONIGHT AT THE KEAT TAF SITE AS DOWNSLOPE FLOW OFF THE
CASCADES CONTINUES.

MOST TAF SITES WILL AT LEAST PARTIALLY DE-COUPLE
TONIGHT...POSSIBLY LEADING TO LLWS BY THE END OF THE TAF PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS...
SPOKANE        58  45  60  39  55  39 /  60  10  40  20  10  40
COEUR D'ALENE  55  44  57  38  55  37 /  90  20  50  30  10  50
PULLMAN        56  46  58  40  56  38 /  80  30  60  50  20  50
LEWISTON       63  47  65  44  64  42 /  80  20  30  50  10  40
COLVILLE       57  41  60  37  58  39 /  70  10  40  20  20  40
SANDPOINT      50  43  53  37  51  38 /  90  30  50  40  30  50
KELLOGG        50  42  51  38  51  36 /  90  70  70  70  40  50
MOSES LAKE     68  45  66  41  62  40 /  20   0  10   0   0  20
WENATCHEE      67  45  62  41  60  39 /  20  10  10   0   0  10
OMAK           64  40  63  38  59  38 /  20  10  10   0   0  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM PDT THIS EVENING
     COEUR D'ALENE AREA...IDAHO PALOUSE...LEWIS AND SOUTHERN NEZ
     PERCE COUNTIES...LEWISTON AREA.

WA...WIND ADVISORY FROM 11 AM THIS MORNING TO 8 PM PDT THIS EVENING
     EAST SLOPES NORTHERN CASCADES...LOWER GARFIELD AND ASOTIN
     COUNTIES...MOSES LAKE AREA...SPOKANE AREA...UPPER COLUMBIA
     BASIN...WASHINGTON PALOUSE...WATERVILLE PLATEAU...WENATCHEE
     AREA.

&&

Hazardous weather outlook, Mar 30, 4:51 AM PST, 6 hours 9 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SPOKANE WA
551 AM PDT WED MAR 30 2011

IDZ001-004-WAZ037-038-043-311315-
NORTHERN PANHANDLE-CENTRAL PANHANDLE MOUNTAINS-
NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS-OKANOGAN VALLEY-
551 AM PDT WED MAR 30 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH IDAHO...
NORTH CENTRAL WASHINGTON AND NORTHEAST WASHINGTON.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

IDZ002-003-026-027-WAZ031>036-041-042-044-311315-
COEUR D'ALENE AREA-IDAHO PALOUSE-LEWISTON AREA-
LEWIS AND SOUTHERN NEZ PERCE COUNTIES-NORTHEAST BLUE MOUNTAINS-
LOWER GARFIELD AND ASOTIN COUNTIES-WASHINGTON PALOUSE-
MOSES LAKE AREA-UPPER COLUMBIA BASIN-SPOKANE AREA-WENATCHEE AREA-
EAST SLOPES NORTHERN CASCADES-WATERVILLE PLATEAU-
551 AM PDT WED MAR 30 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH IDAHO...
NORTH CENTRAL IDAHO...CENTRAL WASHINGTON...EAST CENTRAL
WASHINGTON...NORTH CENTRAL WASHINGTON...NORTHEAST WASHINGTON AND
SOUTHEAST WASHINGTON.

.DAY ONE...TODAY AND TONIGHT

WINDY CONDITIONS WILL IMPACT MUCH OF EASTERN WASHINGTON AND
PORTIONS OF THE IDAHO PANHANDLE TODAY. WIDESPREAD WIND SPEEDS OF
20 TO 30 MPH ARE EXPECTED WITH GUSTS TO 50 MPH OVER MOST OF THE
COLUMBIA BASIN...THE PALOUSE...AND SPOKANE COEUR D'ALENE AREA.
LOCALLY STRONGER WINDS ARE POSSIBLE NEAR THE CASCADES...INCLUDING
THE WENATCHEE AREA...WATERVILLE PLATEAU...AND SURROUNDING WEST
FACING RIDGES.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

5 flood, 1 debris flow. Local standard time, as filed.

Flood, Shoshone

When: March 30, 11:00 AM PST to 2:00 PM PST
Where: Shoshone County, 7.22 mi NNE of Enaville to 6.92 mi NNE of Enaville
Cause: Heavy Rain / Snow Melt
Property damage: $15,000
Reported by: Emergency Manager
Coordinates: 47.662, -116.176

A culvert measuring 24 inches in diameter and 50 feet in length became plugged allowing water to run over Old Coeur D Alene River Road. The water washed out some of the shoulder and road surface. The culvert was severely damaged and will need to be replaced.

Debris Flow, Central Panhandle Mountains

When: March 30, 12:00 PM PST to March 31, 11:59 PM PST
Where: Central Panhandle Mountains forecast zone
Reported by: Emergency Manager
Coordinates: 47.265, -116.491 (the zone’s center; the record gives no point)

Two large debris flows occurred around noon along Forest Road 208. The first slide was near the intersection of Lost Creek. The second slide was near the intersection of Clee Circle Road. No injuries were reported however 14 residents were trapped due to impassible roads and two of these residents had to be evacuated by the sheriff for medical appointments. The road blocked access to six permanent residences. There was an estimated 25,000 cubic yards of rock and mud over the road with the larger slide and 8000 cubic yards associated with the smaller slide. The debris slide was still sliding the first week of April. The estimated cost to remove the earth and fix any damage to the road was 330 thousand dollars.

Flood, Kootenai

When: March 30, 12:00 PM PST to March 31, 11:59 PM PST
Where: Kootenai County, 2.72 mi N of Hauser to 2.73 mi N of Hauser
Cause: Heavy Rain / Snow Melt
Reported by: County Official
Coordinates: 47.789, -117.029

Excessive runoff into Hauser Lake caused the lake to expand out of its banks flooding portions of Hauser Lake Road between Matheson and Ragged Ridge roads.

Flood, Bonner

When: March 31, 12:00 AM PST to 11:59 PM PST
Where: Bonner County, 2.59 mi ENE of Elmira to 5.27 mi E of Cedar Creek
Cause: Heavy Rain / Snow Melt
Property damage: $1.8 million
Reported by: Emergency Manager
Coordinates: 48.498, -116.400

The emergency manager of Bonner County relayed numerous road damage reports from across the county due to flooding from March 31st. The roads included in this report were Fish Creek, Sandborn Creek, West Shingle Mill, Bottle Bay, Dufort, Peninsula, Eastriver, Blacktail, Beare, Eureka, Helen Thompson, Moore Loop, South First Street, Spring Haven Drive, Wells, North Riley Creek, Mountain Creek, Snow Valley, Forest Siding, Comeback Lane, Cocolalla Loop, and LeClerc Road. Several other private roads were also damaged from flooding.

Flood, Latah

When: March 31, 8:00 AM PST to 11:59 PM PST
Where: Latah County, 0.98 mi SSW of Princeton to 4.87 mi S of Princeton
Cause: Heavy Rain / Snow Melt
Reported by: Department of Highways
Coordinates: 46.908, -116.831

North Latah County Road Department reported water over portions of Hatter Creek Road.

Flood, Latah

When: March 31, 8:00 PM PST to 11:23 PM PST
Where: Latah County, 1.47 mi NNE of Howell to 1.45 mi SW of Howell
Cause: Heavy Rain / Snow Melt
Reported by: Department of Highways
Coordinates: 46.751, -116.792

North Latah County Road Department reported water over roadways along portions of Randle Flat Creek Road and Driscoll Ridge Road near Troy, Idaho.

What these are

Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
Debris Flow: A fast-moving slurry of mud, rock and debris, usually on a slope soaked by heavy rain or stripped by a fire.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Idaho in 2011 Every state in 2011 This day in weather history Warnings in Idaho, March 2011

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 285601, 285315, 285319, 286531, 285320, 285325.