Beginning on April 6th and continuing through April 10th a series of Pacific atmospheric rivers were directed into Oregon, southeast Washington and central Idaho saturating the ground with heavy rainfall. 88 inches of rain.
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.
Beginning on April 6th and continuing through April 10th a series of Pacific atmospheric rivers were directed into Oregon, southeast Washington and central Idaho saturating the ground with heavy rainfall. During this 4 day period the COOP station at Kamiah reported 1.86 inches of rain, Elk River reported 2.94 inches of rain, Moscow 3.44 inches, Nez Perce 2.05 inches, Potlatch 2.46 inches, Dworshack Fish Hatchery 3.08 inches , the Lewiston Airport ASOS 0.93 inches and the ASOS at Pullman, WA recording 2.88 inches of rain. By the 9th of April widespread areal flooding issues from swollen streams and rivers as well as mud slides were noted around the region which persisted until the 11th when heavy rain ceased and rivers and streams began to recede.
Kamiah, ID suffered minor flooding of businesses, utilities and park land from the Clearwater River on the eastern boundary of the city and and the breaching of a levee on Lawyer Creek on the southern edge of the city. Lapwai Creek also overflowed it's banks threatening homes and flooding bottom lands and portions of State Highway 95 between Lapwai and Culdesac. Tribal officials of the Nez Perce reservation, which includes most of this region, declared a State of Emergency in response to this flooding event.
In the city of Moscow after receiving 1.47 inches of rain on April 9th, Paradise Creek rose to it's highest flood level on record causing extensive minor flooding of portions downtown Moscow. This flooding was aggravated by a Flash Flood running through residential neighborhoods and business districts laying in in gullies and ravines draining the saturated hills to the north of the city
The Palouse River also reached flood stage with inundation of bottom lands and fields along the river with some minor flooding of agricultural out buildings.
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 Apr 9, 3:28 AM PST, 32 minutes earlier.
Area Forecast Discussion National Weather Service Spokane WA 428 AM PDT Tue Apr 9 2019 .SYNOPSIS... Tuesday through Thursday will be showery and occasionally breezy. Friday will likely be the driest day of the week with the return of precipitation this weekend. Daytime high temperatures this week will mainly be in the 50s. && .DISCUSSION... Today through Wednesday: Starting out the day with a trof overhead containing a cold conditionally unstable airmass that is not only conducive to showery weather but possibly some spotty, weak, shallow, and short lived pulse thunderstorms. High resolution short term models like the HRRR suggest movement of any thunderstorms that form will be to the southeast at 15 mph or so and they would be capable of producing infrequent lightning, gusty wind, brief heavy downpours, and soft hail. As the trof moves east and shortwave ridging replaces it in its wake later today and overnight the pressure gradient tightens, especially across the cascades, thus winds through the Cascade gaps and on into the Waterville Plateau and portions of the Columbia Basin should blow robustly with gusts as a result later today and tonight. The shortwave ridging will allow for drying tonight as well with some decrease in cloud cover. The shortwave ridging is fleeting however as it gets replaced with a northwest flow more cluttered with moisture and small scale disturbances running through it which allows for a reintroduction of pops for showery conditions, and possibly more spotty surface based weak, shallow, and short-lived pulse thunderstorms. Storm motion would be more west to east at 15 mph or so for any thunderstorm that forms Wednesday afternoon. In addition a river statement and blurb added in the hazardous outlook address increased river streamflow resulting from the wet weather this week. /Pelatti Wednesday night through Thursday night...A progressive, wet and unsettled pattern will be over the region through the extended period. The first weak weather disturbance will drop through the region Wednesday night and will keep a good chance of rain and snow showers across the Cascades and the Idaho Panhandle mountains, with the showers building back as far west as the West Plains. A second wave will slide down the backside of the exiting trough late in the day on Thursday and bring another shot of moisture to the region with showers remaining along the ID/MT border through Thursday evening. It looks like the Columbia Basin, the lower east slopes of the Cascades and the Okanogan valley will get missed with this round of moisture. Snow levels around 4000-4500 feet will drop to around 3000 feet by Thursday morning with snow accumulations of 1-3 inches in the Cascades and 3-5 inches for the Panhandle mountains and locally as high as 7 inches in the mountains south of I-90. Friday through Tuesday...The pattern will repeat a couple more times as high pressure rebuilds into the region during the day Friday. Northwest-northerly flow and lingering low level moisture will keep a chance of rain and snow showers in the Panhandle mountains Friday afternoon, otherwise conditions will be dry with variable clouds. The ridge will be short lived as another Pacific disturbance will move into the region Saturday afternoon. This will keep the weather cool and showery the remainder of the weekend with valley rain and mountain snow. We should see somewhat of a break Sunday night and early Monday before yet another wave will move into the region Monday night and Tuesday for more showers. Temperatures will be in the mid 50s to lower 60s and very near normal. Tobin && .AVIATION... 12Z TAFS: Ongoing showers and consider moisture left behind from earlier showers will allow fog and low clouds to linger in spots and produce IFR ceilings and visibilities at times but mainly this morning. Otherwise showers may decrease tonight over the far west with wind increasing through the gaps allowing for a windy afternoon and evening at KEAT and KMWH. Wednesday morning upper level northwest winds may be robust enough to produce some low level wind shear for a spell until mixing Wednesday afternoon mitigates it. /Pelatti && .PRELIMINARY POINT TEMPS/POPS... Spokane 52 34 55 35 53 32 / 50 20 20 40 40 20 Coeur d'Alene 52 35 52 36 51 31 / 60 40 20 60 40 20 Pullman 50 35 50 36 48 32 / 60 50 10 50 40 20 Lewiston 56 41 55 41 54 38 / 50 50 10 50 40 30 Colville 56 31 61 33 55 28 / 80 10 30 60 40 20 Sandpoint 51 35 51 36 49 32 / 70 30 30 60 50 20 Kellogg 48 37 48 36 47 32 / 70 50 30 70 60 20 Moses Lake 62 36 61 36 59 35 / 20 0 10 10 20 10 Wenatchee 59 39 57 38 55 37 / 10 0 20 10 20 20 Omak 60 36 59 35 57 35 / 30 0 20 10 30 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. &&
Hazardous Weather Outlook National Weather Service Spokane WA 333 AM PDT Tue Apr 9 2019 IDZ026-027-WAZ031-032-101500- Lewiston Area-Lewis and Southern Nez Perce Counties- Northeast Blue Mountains-Lower Garfield and Asotin Counties- 333 AM PDT Tue Apr 9 2019 This Hazardous Weather Outlook is for portions of North Central Idaho and Southeast Washington. .DAY ONE...TODAY AND TONIGHT Continued rises on rivers and streams are expected. Localized debris flows are also possible. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY Rises on rivers and streams may linger on into Wednesday with gradual decline possible through the remainder of the week. Localized debris flows will remain possible. IDZ001>004-WAZ033>038-041>044-101500- Northern Panhandle-Coeur d'Alene Area-Idaho Palouse- Central Panhandle Mountains-Washington Palouse-Moses Lake Area- Upper Columbia Basin-Spokane Area-Northeast Mountains- Okanogan Highlands-Wenatchee Area-East Slopes Northern Cascades- Okanogan Valley-Waterville Plateau- 333 AM PDT Tue Apr 9 2019 This Hazardous Weather Outlook is for portions of North 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...WEDNESDAY THROUGH MONDAY No hazardous weather is expected at this time.
The Missoula radar (KMSX), 180 km away, was scanning. The volume nearest the first event began at 11:57 UTC.
4 flood, 1 debris flow, 1 flash flood. Local standard time, as filed.
Several mud slides were reported over Highway 12 just west of Kamiah on the morning of April 9th. One of the slides completely covered the road and caused the temporary closure of this primary road through the region while crews cleared the debris.
High water in the Clearwater River augmented by a levee break along Lawyer Creek produced extensive flooding near the confluence of these two streams on the eastern edge of the city of Kamiah. The flood waters were reported to be waist deep in the Kamiah Riverfront Park. Flood waters also partially inundated a lumber yard, undermined a railroad grade and trestle crossing Lawyer Creek and high water prohibited access to the city's water plant. The levee was temporarily repaired by the public works department as the creek receded.
Lapwai Creek flooded bottom lands and flowed over Highway 95 in places between Lapwai and Culdesac causing the temporary closure of this primary route through the region. A few homes were threatened by the flood waters but no damage to any structures was reported.
The USGS River Gage on Paradise Creek in Moscow recorded a sharp rise to above the Flood Stage of 9.2 feet at 2:45 PM PDT on April 9th. The creek continued to rise passing through the Moderate Flood Stage of 10.0 feet at 7:00 PM. The creek continued to rise and crested at 11.4 feet at 7:15 PM which is a record high crest beating the previous record crest of 11.3 feet set in 1996. The creek then quickly receded passing below the moderate Flood Stage at 8:00 PM and then below Flood Stage at 9:15 PM PDT.
Heavy rain during the afternoon and evening of April 9th caused Paradise Creek running through Moscow to rapidly rise and inundate lower elevation portions of the city along the creek. In addition heavy rain in the hills north of Moscow caused flash flooding in the northeastern areas of the city as runoff drained through valleys and ravines along North Polk Street and into the East D street neighborhood, then through downtown before draining into Paradise Creek. In some areas flood waters were reported to be 3 feet deep with numerous roads, intersections and underpasses impassable. Most of the reported damage involved basement and first floor flooding of buildings.
The USGS River Gage on the Palouse River near Potlatch recorded a rise to the Flood Stage of 15.0 feet at 8:30 PM PDT on April 9th. The river continued to rise and pass through the Moderate Flood Stage of 16.0 feet at 10:45 pm on the 9th. The river crested just under the Major Flood Stage of 17.0 feet at 5:00 am on the 10th and then began receding. The river passed down through the Moderate Flood Stage at 3:00 PM on the 10th and then receded below the Flood Stage at 9:15 PM PDT on April 10th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2019Every state in 2019This day in weather historyWarnings in Idaho, April 2019
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: 817299, 817308, 817321, 817297, 818099, 817289.