Flash Flood Warning Issued for Armstrong, Fayette, Indiana, Westmoreland Counties PA

Source: NOAA · Southwestern Pennsylvania

This alert is no longer in effect.

NOAA issued it on August 20, 2026, 3 days ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).

Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.

NWS Pittsburgh has issued a Flash Flood Warning for four southwestern Pennsylvania counties until 2:15 PM EDT August 20 due to thunderstorms producing heavy rain.

Read this weather record in 30 seconds

Record type
Flash Flood Warning
Affected area
Southwestern Pennsylvania
Issued
August 20, 2026
Issuing authority
NWS Pittsburgh PA

Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.

Record status: historical. It was issued 3 days ago; use the issuing agency's live warning service for current conditions in Southwestern Pennsylvania.

Alert Details

Flash Flood Warning issued by NWS Pittsburgh PA (NOAA). Effective from August 20, 2026 at 11:10 AM EDT until August 20, 2026 at 2:15 PM EDT. Severity: Severe. Certainty: Likely. Urgency: Immediate.

Affected Areas

Armstrong County (southwestern), Fayette County (north central), Indiana County (southwestern), and Westmoreland County in southwestern and west central Pennsylvania. Specific locations include Greensburg, Jeannette, Latrobe, Vandergrift, Apollo, Murrysville, Mount Pleasant, Scottdale, McChesneytown-Loyalhanna, Blairsville, Manor, Youngwood, Derry, Delmont, Lawson Heights, New Stanton, and Leechburg.

What You Should Do

Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles.

Expected Conditions

Doppler radar indicated thunderstorms producing heavy rain. Up to 0.5 inches of rain have fallen with additional rainfall amounts up to 1 inch possible. Flash flooding is ongoing or expected to begin shortly.

Timeline

Alert effective August 20, 2026 at 11:10 AM EDT and expires August 20, 2026 at 2:15 PM EDT.

Original source: NOAA Official Notice ↗

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Nationwide notices with similar length or severity timing 8

Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.

Frequently Asked Questions

Common questions about this NWS weather alert.

What is this NWS weather alert about?
NWS Pittsburgh has issued a Flash Flood Warning for four southwestern Pennsylvania counties until 2:15 PM EDT August 20 due to thunderstorms producing heavy rain.
Which agency issued this alert?
This alert was issued by NOAA. The original notice is available at the source link at the bottom of this article.
How severe is this alert?
This alert is classified as "high" severity. Take precautions and monitor for updates.
What area is affected?
This alert affects Southwestern Pennsylvania. Check with NOAA for the most current geographic scope.
Where can I find more Weather Alerts updates?
Browse the full Weather Alerts feed on Areazine at areazine.com/weather/ for the latest updates from NOAA and other agencies.