FirstAlerts

Flood Watch for Yellowstone National Park and Wyoming Ranges Extended Through Sunday Morning

The National Weather Service has extended the Flood Watch for portions of Wyoming, including Yellowstone National Park, now running through Sunday morning, August 30, 2026.

4 reports on this incident · first at Aug 28, 2026, 12:51 p.m. ET

By AI ReporterWritten Aug 28, 2026, 1:01 p.m. ET
The National Weather Service in Riverton, Wyoming, has extended a for portions of central, northwest, and west central Wyoming, including Yellowstone National Park, the Absaroka Mountains, Teton and Gros Ventre Mountains, Jackson Hole, Wind River Mountains West, Star Valley, and Salt River and Wyoming Ranges. The now runs from 6 PM MDT Saturday, August 29, 2026, through Sunday morning, August 30, 2026, a longer window than initially issued. The covers the cities of Jackson, Alpine, Afton, Old Faithful, Mammoth, Lake, Star Valley Ranch, and Thayne. Excessive rainfall may cause flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Residents in flood-prone areas should monitor forecasts and be prepared to take action if flooding develops.

Earlier reports

  1. Aug 28, 2026, 12:56 p.m. ET

    Flood Watch Issued for Yellowstone National Park and Wyoming Ranges Through Sunday Morning

    The National Weather Service in Riverton, Wyoming, has issued a Flood Watch for portions of central, northwest, and west central Wyoming, effective from 6 PM MDT Saturday, August 29, through noon MDT Sunday, August 30. The watch covers Yellowstone National Park, the Absaroka Mountains, the Teton and Gros Ventre Mountains, Jackson Hole, the Wind River Mountains West, Star Valley, and the Salt River and Wyoming Ranges, including the cities of Jackson, Alpine, Afton, Old Faithful, Mammoth, Lake, Star Valley Ranch, and Thayne.

    Excessive rainfall may cause flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. The National Weather Service advises monitoring later forecasts and being alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

  2. Aug 28, 2026, 12:53 p.m. ET

    Flood Watch for Yellowstone National Park, Absaroka Mountains, Teton and Gros Ventre Mountains Through Sunday Morning

    The National Weather Service in Riverton, Wyoming, has issued a Flood Watch for portions of central, northwest, and west central Wyoming, warning that excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations.

    The watch is in effect from 6 PM MDT Friday, August 28, 2026, through Sunday morning, August 30, 2026. It covers Yellowstone National Park, the Absaroka Mountains, the Teton and Gros Ventre Mountains, Jackson Hole, the Wind River Mountains West, Star Valley, and the Salt River and Wyoming Ranges, including the cities of Jackson, Alpine, Afton, Old Faithful, Mammoth, Lake, Star Valley Ranch, and Thayne.

    Residents are advised to monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

  3. Aug 28, 2026, 12:51 p.m. ETFirst report

    Flood Watch Issued for Parts of Wyoming Through Sunday Morning

    The National Weather Service in Riverton, Wyoming, has issued a Flood Watch for portions of central, northwest, and west central Wyoming, effective from 6 PM MDT Saturday, August 29, through Sunday morning, August 30, 2026. The watch was issued at 10:43 AM MDT on August 28.

    The watch covers seven zones, including Yellowstone National Park, the Absaroka Mountains, the Teton and Gros Ventre Mountains, Jackson Hole, the Wind River Mountains West, Star Valley, and the Salt River and Wyoming Ranges. Cities in the affected area include Jackson, Alpine, Afton, Old Faithful, Mammoth, Lake, Star Valley Ranch, and Thayne.

    Excessive runoff from heavy rainfall may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Residents are advised to monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

Was this report accurate and useful?

Sources

Revision history

  1. Version 128 Aug 2026, 17:01current

    First published.

  2. Version 128 Aug 2026, 16:53current

    First published.

  3. Version 128 Aug 2026, 16:51current

    First published.

  4. Version 128 Aug 2026, 16:56current

    First published.

How we work

This site models an investigative reporter rather than a wire desk. The aim is the most complete, accurate and timely account we can assemble — all three, not a trade between them. Reports go out within minutes of the coverage they are built from, carrying context a newsroom would otherwise need a day and a records request to gather: what has happened at this place before, what the operator’s record is, which aircraft it actually was.

Reports are built from primary sources — accident and court records, official registries, weather observations, agency statements — and from reputable news organisations, each named where their reporting is used. Facts are extracted before anything is written, and every one must be supported by a quotation found in the source itself; the model that writes the report is given only those verified facts and never sees the article, so it cannot introduce a detail no source stated.

Where sources disagree we publish the disagreement, attributed, rather than picking a figure. Where a fact comes from a record rather than a reporter, we say so, and the language matches: an instrument reading is never described as something anyone confirmed. Some things are deliberately withheld — a suspect is not named until an agency names them on the record, victims until families or officials release them — and corrections appear as visible revisions, never as silent edits.

None of that makes a report true. A quotation check proves a source said something, not that it was right, and an automated system can be confidently wrong in ways the checks do not catch. If something here is wrong, the feedback above is how it gets found. The full methodology, including what we refuse to publish.