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  "path": "/2026/05/severe-thunderstorm-threat-on-thursday.html",
  "publishedAt": "2026-05-28T04:49:21.908Z",
  "site": "https://cliffmass.blogspot.com",
  "tags": [
    "Patreon supporters"
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  "textContent": "There is a significant chance of several thunderstorms tomorrow (Thursday) over eastern Washington, eastern Oregon, and northern Idaho, with the potential for heavy rain, lots of lightning, and strong winds.\n\nThe Spokane National Weather Service office has a severe thunderstorm warning out:\n\n\n\n\nAnd the NOAA Storm Prediction Center has a moderate level of warning (yellow), which is very unusual for our region.\n\n\n\n\n\nThe predicted strong thunderstorms will move in during the afternoon. The National Weather Service high-resolution HRRR model shows an intense line of thunderstorms (convection) moving through around 10 PM Thursday.\n\n\n\n\n\n\n\nThree hours later, the line crosses the Canadian border with some showers reaching western Washington.\n\n\n\n\n\n\n\nThe line of thunderstorms will be associated with very strong winds in eastern Washington, with some gusts exceeding 60 mph (see wind gust forecast at PM tomorrow, below). I suspect the wind farms will be \"feathered\" to reduce damage.\n\n\n\n\n\n\n\n\nHeavy precipitation will also fall, with the HRRR model going for huge totals over the Oregon Cascades. Substantial rainfall (over a half inch) over the Yakima River drainage.\n\n\n\n\n\n\n\n\n\n\nThe UW forecast model is also producing heavy rain over eastern Washington, which should be a great relief to those concerned about drought.\n\n\n\n\nLocalized flooding in river valleys is possible.\n\n\n\n\n**Why the potential for such an intense event?**\n\n\nThe \"set-up\" is illustrated in the upper-level map below (for 500 hPa pressure, about 18,000 ft).\n\n\n\n\nAn upper-level trough of low pressure is approaching (yellow arrow), producing uplift that can release atmospheric instability. A second trough to the south (red arrow) is moving moist, unstable air in from the southwest northward into our region. Upslope on the eastern slopes of the Cascades will contribute additional meteorological fuel.\n\n\n\n\n\n\n\n\n\n\nIn short, later tomorrow will be an exciting time from the Cascades and to the east.\n\n\n\n\n**\nAnnouncement**\n\n**\n**\n\nI will hold a special online Zoom session at 10 AM on Saturday for Patreon supporters.\n\n\n",
  "title": "Severe Thunderstorm Threat On Thursday",
  "updatedAt": "2026-05-28T04:49:21.908Z"
}