Flood Advisory for City and Borough of Juneau

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Bulletin details

An atmospheric river storm system moving into the panhandle is expected to bring two rounds of heavy rainfall to the Juneau area. The first will continue through today, while the second wave will bring higher rainfall amounts tonight into Friday morning. This longer duration of heavy rainfall with not much of a break in between will allow for river and creek rises, with minor flooding of small streams expected going into Friday morning. * WHAT...Small stream flooding caused by excessive rainfall is expected. * WHERE...Areas around Montana Creek And Jordan Creek. * WHEN...Until 130 AM AKDT Saturday. * IMPACTS...Minor flooding in low-lying and poor drainage areas. Water over roadways. Some low-water crossings may become impassable. * ADDITIONAL DETAILS... At 146 PM AKDT, satellite estimates indicate heavy rain across the advisory area. Rapid river rises will cause minor flooding of small streams, especially near Montana Creek And Jordan Creek. Between 0.75 and 1 inch of rain has fallen. The expected rainfall rate is 0.15-0.3 inches in 1 hour. Additional rainfall amounts of 1.5 to 2.5 inches are possible. Montana Creek is anticipated to begin to fall below Minor flood stage by late Friday morning to midday, while Jordan Creek will stay above Minor flood stage a bit longer into the day, falling below Minor flood stage by Friday night. For Jordan Creek near Juneau: At 12:00pm the stage was 7.8 feet. Flood Stage is 9.7 feet. Forecast: A crest around 9.9 feet is expected around 1:00pm Friday. Water levels will go above Minor flood stage around 8:00am. Water levels will go below Minor flood stage around 10:00pm. Impacts: At 9.2 feet: This is the stage when Jordan Creek is at bankfull and water will begin to inundate areas along the edges of the creek near Race Reality and Jordan Square. At 9.7 feet: Water will inundate the Jordan Square's front and back parking lots, around Jordan Creek office condominiums with up to one foot of water. Some residential driveways will be flooded and cut off. For Montana Creek at Back Loop Bridge: At 12:00pm the stage was 11.2 feet. Flood Stage is 14.5 feet. Forecast: A crest around 14.7 feet is expected around 7:00am Friday. Water levels will go above Minor flood stage around 5:00am. Water levels will go below Minor flood stage around 9:00am. Impacts: At 14.5 feet: Water begins flowing over the low water crossing on Montana Creek Road. Bankfull conditions at the gauge with water starting to inundate adjacent undeveloped fields along Mendenhall Loop Road. At 15.5 feet: Up to one half foot of water will flow over the low water crossing on Montana Creek Road after the community gardens. Water will approach and begin to inundate yards of residences along the Northwest side of Mendenhall Loop Road.