A low pressure system off the WA coast continued to push weak waves of instability across Eastern WA. The instability was able to produce mid morning thunderstorms with large hail.
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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.
A low pressure system off the WA coast continued to push weak waves of instability across Eastern WA. The instability was able to produce mid morning thunderstorms with large hail.
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 Aug 12, 3:49 AM PST, 3 hours 31 minutes earlier.
Area Forecast Discussion National Weather Service Spokane WA 449 AM PDT Fri Aug 12 2022 .SYNOPSIS... Moisture rounding a low pressure system in the eastern Pacific will keep showers and thunderstorms in the forecast at times early Saturday morning. Once again a few of the thunderstorms could be strong and produce large hail and damaging winds especially over extreme eastern Washington into north Idaho. A cold front passage on Saturday will result in breezier winds for the afternoon and usher in much drier air. After a brief cool down for the weekend, hotter weather is expected to return through at least midweek. && .DISCUSSION... Today and tonight: Another round of thunderstorms is expected for the Inland Northwest. The Low off the coast continues to promote instability across the Pacific Northwest. Today is expected to be similar to yesterday but the areas impacted will generally be the Idaho Panhandle and the Northern Mountains. The thunderstorm threat is expected to start late morning and continue through the evening. The thunderstorm activity will diminish behind a cold front overnight and early Saturday morning. The environment in these areas is expected to support strong thunderstorms. Cape values are 2000-3000 Joules. Lapse rates are around 8C/KM. Shear values are expected to be 35-40 kts. PW amounts are expected to be near one inch. The threats from the storms are expected to be abundant lightning, hail, gusty winds, and heavy downpours. Some storms could produce severe hail of an inch or greater. Wind gusts of 35 to 45 MPH are possible. Luckily these storms are expected to bring decent amounts of rain and dampen any possible fire starts. Winds across the Basin will generally be in the teens with gusts near 25 MPH. Highs for the day are still expected to be above normals. The region can expect widespread 90s. Saturday: As the Low continues to move North, high pressure will begin to build into the region. It will lead stable dry condition. Winds will continue to be breezy across the Basin leading to increase fire concerns as RHs are in the upper teens and low 20 percents. Highs will dip into the 80s. Lows will be in the 50s and low 60s. /JDC Sunday through Wednesday...The ensemble suites are in very good agreement through this period by showing a gradual rebound of the upper level ridge over the Inland Northwest. So what does this mean? It means we are looking at a period with dry weather and increasingly warm temperatures. Each day we expect to see about 1-2C of warming at 850 mbs and likely peaking on Wednesday. On Sunday we will start with 850 mb temperatures ranging from 19-21c which equates to seasonable temperatures with highs in the mid 80s to mid 90s. By Wednesday those values will range from 27-29C (and a little cooler from the Canadian ensemble means) which equates to another day of potential triple digit heat. Right now we have forecast highs ranging from the mid 90s in the far northern Idaho Valleys to the mid 100s over the Okanogan Valley, Wenatchee Valley, and LC Valley. Some of the forecast values are near record highs for the date including: Wenatchee: Forecast: 102F Record: 104F set in 1977 Omak: Forecast: 104F Record: 104F set in 2020 Ephrata: Forecast 102F Record: 104F in 1977 Meanwhile we expect conditions to be considerably drier than our current air mass as the precipitable water values drop from over an inch today to nearly half that by Saturday night/Sunday. Fortunately this dry air mass isn’t expected to be accompanied by any strong wind events during this period. Nonetheless the combination of the much drier air, clear skies, and increasing heat will continue to desiccate the fuels and any possible holdovers from recent and upcoming lightning. As the week progresses, precipitable water values will gradually increase as we transition from westerly flow to more of a southerly one by midweek with the retrogression of the Four Corners High. From Thursday and Friday, the confidence in the forecast begins to plummet somewhat, as about a quarter of the ensemble members (mostly from the Canadian) shove the ridge into Montana and bring a stronger trough in western Washington. Meanwhile about 40 percent of the ensemble members amplify the ridge even further. If the former were to occur, we’d be looking at a significant cool down, likely accompanied by some breezy winds and the possibility of more precipitation. However if the latter occurs its more of the same and in fact it could be hotter than Wednesday. The ensemble trends of the Euro and Canadian means is toward the cooler solutions, but we shall see. fx && .AVIATION... 12Z TAFs: VFR conditions will are expected for TAF sites. Late morning and afternoon convection is expected to produce isolated thunderstorms in the Idaho Panhandle and Northern Mountains. There is the slight chance of storms impacting LWS- PUW-CDA-SFF but confidence is very low. Winds will increase across the Basin with gusts near 25 kts. /JDC && .PRELIMINARY POINT TEMPS/POPS... Spokane 95 60 86 56 87 56 / 10 10 0 0 0 0 Coeur d'Alene 95 59 85 53 86 53 / 10 20 0 0 0 0 Pullman 90 54 82 51 84 52 / 10 20 0 0 0 0 Lewiston 98 67 91 61 93 62 / 20 20 0 0 0 0 Colville 96 52 88 47 88 48 / 20 20 10 0 0 0 Sandpoint 93 57 85 51 86 50 / 20 20 10 0 0 0 Kellogg 93 62 83 59 84 60 / 20 30 10 0 0 0 Moses Lake 96 58 89 53 90 56 / 10 0 0 0 0 0 Wenatchee 96 62 86 59 90 63 / 10 10 0 0 0 0 Omak 98 61 91 56 92 59 / 20 20 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. &&
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SPOKANE WA
751 AM PDT FRI AUG 12 2022
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0720 PM HAIL 8 SE NORTHPORT 48.85N 117.63W
08/11/2022 E0.75 INCH STEVENS WA TRAINED SPOTTER
DELAYED REPORT FROM THURSDAY EVENING.
&&The Spokane radar (KOTX), 46 km away, was scanning. The volume nearest the first event began at 15:20 UTC.
3 hail. Local standard time, as filed.
A thunderstorm formed near Malden and moved Northeast near Plaza. It produced hail the size of half an inch to 1.5 inch.
A thunderstorm developed East of Connell and traveled North toward Ritzville. It produced hail 1.5 inch in Lind WA around 0709PST. It also had reports of 0.75 inch and 1 inch.
A thunderstorm developed near Havillah and traveled Northeast into Canada. Public reported 1 inch hail near Chesaw, WA at 1730PST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2022Every state in 2022This day in weather historyWarnings in Washington, August 2022
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: 1054417, 1054418, 1054420.