An unusually wet spring over north Idaho caused saturated soil conditions which continued to promote isolated debris flows in the mountainous terrain through the month of May.
Every event with a place to put it. Tap one for its entry below.
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.
The episode as NWS OTX wrote it up.
An unusually wet spring over north Idaho caused saturated soil conditions which continued to promote isolated debris flows in the mountainous terrain through the month of May.
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 May 29, 3:23 AM PST, 2 hours 37 minutes earlier.
Area Forecast Discussion National Weather Service Spokane WA 423 AM PDT Mon May 29 2017 .SYNOPSIS... High pressure continues over the Inland Northwest through Tuesday with unseasonably warm temperatures. There is a small chance of thunderstorms in the higher elevations, otherwise expect dry weather. This warm spell will contribute to rises on rivers from the Cascades into north Idaho. A cold front arrives Tuesday night with a better chance of showers and thunderstorms. This will be followed by cooler and unsettled weather for Wednesday into the rest of the week. && .DISCUSSION... Today through Tuesday: Warm weather continues, with limited shower and thunderstorm chances. A ridge of high pressure centered over the Inland NW this morning will start to edge east. Moisture lingering around the north to eastern CWA and increasing toward the Cascades with be accompanied by the reemergence of afternoon instability. Subtle vorticity lobes in the westerly flow and orographic ascent will lead to an increase in cumulus about the mountain zones this afternoon. This will be accompanied by a slight risk for showers and thunderstorms in the Cascades, the northern WA and ID Panhandle mountains, as well as the Blues. Tonight the risk will wane for most locations with the loss of daytime heating, though some threat may linger near the Cascade crest with the onshore flow. Tuesday the ridge axis shifts into the northern Rockies and the southwest flow increases. Moisture further deepens around the Cascades ahead of the approaching system. A limited shower and thunderstorm threat will be found near the Blues and far northeastern mountains with the afternoon heating and instability. A better threat of showers and thunderstorms will be developing within the Cascades, especially late. Middle to high clouds will gradually increase from the west elsewhere. Easterly winds will increase. Temperatures will remain above normal by about 10-15 degrees, with afternoon highs in the 80s to lower 90s. Tuesday will be the warmest day for most spots. The main exception will be toward the Cascades where the increased onshore flow and increased cloud cover and shower chances may hold temperatures down compared to today. /J. Cote' Tuesday night and Wednesday: Models are in good agreement in breaking down the warm upper ridge with an initial short wave passage and surface cold front Tuesday night and into Wednesday morning. The main frontal transit will occur overnight Tuesday and into Wednesday morning...not the most favorable time for serious thunderstorm activity...however enough mid level instability and plenty of moisture will be able to be exploited by the short wave dynamics to produce a few thunderstorms moving off the Cascades in the evening and nocturnally transiting the basin and northern mountains overnight...and redeveloping with a surface based instability component during the day Wednesday concentrated over the Idaho Panhandle. Otherwise...breezy conditions will develop over the basin as cooler air behind the front invades through the Cascade gaps. A general threat of showers with a few thunderstorms looks plausible during this evolution. Wednesday night through Sunday: Although timing differences develop between models through this period...all of them depict a series of short wave disturbances transiting the forecast area in a more progressive pattern for the remainder of the week and into next weekend. None of these waves look particularly strong...but each will be capable of triggering some showers or a few thunderstorms mainly over the mountains north and east of the basin...with occasionally breezy conditions in the basin itself. Temperatures will cool back into the normal range during this pattern...with mainly 70s readings in the populated areas during the day and 40s to lower 50s at night. /Fugazzi && .AVIATION... 12Z TAFS: Dominating ridge will lead to VFR conditions at all TAF sites. Isolated thunderstorms possible near the Cascade crest and over the higher terrain of northeast WA and the northern ID Panhandle this afternoon, away from the TAFs. /J. Cote' && .PRELIMINARY POINT TEMPS/POPS... Spokane 86 60 87 58 75 53 / 10 0 0 40 20 10 Coeur d'Alene 84 56 86 55 74 51 / 10 0 0 30 20 20 Pullman 83 55 85 55 73 52 / 10 0 0 20 20 30 Lewiston 90 59 91 61 80 56 / 10 0 0 20 20 30 Colville 87 56 87 58 76 52 / 10 0 0 40 40 20 Sandpoint 83 53 84 54 75 49 / 10 10 10 10 40 40 Kellogg 84 53 84 53 76 47 / 10 10 0 10 30 50 Moses Lake 92 58 94 60 83 55 / 10 0 0 40 10 10 Wenatchee 90 64 89 58 80 58 / 10 10 10 30 10 10 Omak 89 58 90 60 81 53 / 10 10 10 50 40 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. &&
Hazardous Weather Outlook National Weather Service Spokane WA 501 AM PDT Mon May 29 2017 IDZ002>004-026-027-WAZ031>036-041-044-301215- COEUR D'ALENE AREA-IDAHO PALOUSE-CENTRAL PANHANDLE MOUNTAINS- 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-WATERVILLE PLATEAU- 501 AM PDT Mon May 29 2017 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 No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A cold front passes between Tuesday night and Wednesday, with a chance of showers and thunderstorms. Confidence in precise coverage and intensity of thunderstorms is low, but any stronger thunderstorms could produce locally heavy downpours, gusty winds and hail. IDZ001-WAZ037-038-042-043-301215- NORTHERN PANHANDLE-NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS- EAST SLOPES NORTHERN CASCADES-OKANOGAN VALLEY- 501 AM PDT Mon May 29 2017 This Hazardous Weather Outlook is for portions of North Idaho... North Central Washington and Northeast Washington. .DAY ONE...TODAY AND TONIGHT The probability of widespread hazardous weather is low. Warm temperatures will result in increased snowmelt, with continued or additional rises on area rivers and streams. Localized mainstem river flooding is possible near the Cascades. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY Warm temperatures will result in increased snowmelt, with continued or additional rises on area rivers and streams. Localized mainstem river flooding is possible. A cold front passes between Tuesday night and Wednesday, with a chance of showers and thunderstorms. Confidence in precise coverage and intensity of thunderstorms is low, but any stronger thunderstorms could produce locally heavy downpours, gusty winds and hail.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SPOKANE WA
650 AM PDT MON MAY 29 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0648 AM DEBRIS FLOW 1 SW KENDRICK 46.60N 116.67W
05/29/2017 LATAH ID DEPT OF HIGHWAYS
IDOT: HWY 3. THE ROAD IS CLOSED. THERE'S
BEEN A LANDSLIDE.
&&
JDCThe national radar mosaic for the moment the first event began.
1 debris flow. Local standard time, as filed.
A debris flow blocked Highway 3 near Kendrick.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2017Every state in 2017This day in weather historyWarnings in Idaho, May 2017
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: 699573.