Flood — Susitna Valley, Alaska

2022-08-10 to 2022-08-11 · near Nancy Lake, Susitna Valley, Alaska

Event narrative

Numerous roads and low lying properties were reported to be flooded Monday night and Tuesday downstream from the Parks Highway Bridge and were impacted by flood waters for about 24-36 hours.

Wider weather episode

The set up was a broad longwave trough in place over much of the Bering Sea through southern Alaska. Embedded in this broad longwave trough was an upper level low meandering over the Yukon-Kuskokwim Delta. Multiple upper level shortwaves rotated around this upper level low along with a jet stream aimed right up Cook Inlet into Southcentral. The southwesterly flow at 700 millibars was also very moist with all this moisture being advected northeastward into the Cook Inlet region and Mat-SU Valleys. As a result, heavy rain occurred throughout the region resulting in flooding for some areas.

View location on OpenStreetMap → (61.5937, -149.7605)

Source: NOAA Storm Events Database, event_id 1050702. Narrative written by the NWS forecast office that issued the report.