038
WGAK47 PAJK 121831
FLWAJK

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Juneau AK
1031 AM AKDT Tue Aug 12 2025

.USGS laser gauge data from Suicide basin indicates a release from
the basin has started. Mendenhall lake levels are also showing a
release has started. A crest is expected around Wednesday afternoon
near record levels of somewhere between 16.3 and 16.8ft.

AKZ325-130245-
/O.NEW.PAJK.FA.W.0002.250812T1831Z-250814T1600Z/
/00000.0.GO.000000T0000Z.000000T0000Z.000000T0000Z.OO/
City and Borough of Juneau AK-
1031 AM AKDT Tue Aug 12 2025

...FLOOD WARNING FOR A GLACIER-DAMMED LAKE OUTBURST IN EFFECT UNTIL
8 AM AKDT THURSDAY...

* WHAT...Flooding caused by a glacier-dammed lake outburst is
  expected.

* WHERE...The Mendenhall Lake and River near areas around the
  glacier visitor center, the Mendenhall campground, Skaters Cabin
  Road, View Drive and possibly below Back Loop bridge.

* WHEN...Until 800 AM AKDT Thursday.

* IMPACTS...Flooding of rivers, creeks, streams, other low-lying
  areas and flood-prone locations is imminent or occurring.

* ADDITIONAL DETAILS...
  - At 1029 AM AKDT, gauge reports indicated a glacier-dammed
    lake outburst across the warned area. Flooding is ongoing or
    expected to begin shortly, especially near the Mendenhall
    Lake and River.

  - The outburst flood forecast is based on an estimated volume
    of water in the glacier dammed lake and an estimated release
    rate based on previous events.  The extent of water drainage
    within the basin (partial or full) can vary widely between
    outburst flood events and is a major source of uncertainty in
    the forecast, particularly with regard to the peak flood
    stage.

  - For Mendenhall Lake :
    At 9:45am the stage was 9.6 feet.
    Flood Stage is 9.0 feet.
    Forecast: A crest around 16.6 feet is expected around 4:00pm
    Wednesday.
    Wednesday.
    Water levels will go above 10 feet around 4:00pm Tuesday.
    Water levels will go above 12 feet around 2:00am Wednesday.
    Water levels will go above major flood stage around 9:00am
    Wednesday.

    Impacts:
    At 9.5 feet: Water levels up to 0.5 feet will cover Skaters
    Cabin Road between Skaters Cabin and West Glacier Trailhead.
    Campsite 7 will be flooded with water starting to flow over
    the road between campsites 8 and 9 in the Mendenhall
    Campground.

    At 10.0 feet: Water levels will inundate Mendenhall
    Campground with up to 3 feet of water covering low areas as
    well as up to 1.5 feet of water covering Skaters Cabin Road.
    Portions of West Glacier Trail will be impassable. Areas
    along View Dr will start to flood and cause minor flooding of
    yards. Closure of pedestrian pathways beneath Brotherhood
    Bridge and the trail system on the west side of Mendenhall
    River during outburst events.

    At 10.5 feet: Significant flooding along the Mendenhall Lake
    area with more than 3 feet of water in places near Mt.
    McGinnis trailhead and the Mendenhall Campground will be
    evacuated.

    At 11.0 feet: Some homes along View Dr will have up to 1.5
    feet of water in yards. Locations below back loop bridge will
    see bank erosion along unreinforced river banks along with
    hazardous navigation from debris in the river. Homes along
    the river on Meander Way will begin to see flooding of some
    backyards on the outside of the HESCO levee. Portions of the
    Dredge Lake Trail System will be impassable. Flood waters
    start to reach Dredge Lake.

    At 11.5 feet: The low section of road past 9374 View Dr will
    begin to flood along with water approaching some homes
    towards the end of road.

    At 12.0 feet: Significant bank erosion along unreinforced
    river banks. The low section of road past 9374 View Dr will
    be flooded with up to 0.5 feet of water. Some houses on the
    south side and the east end of View Dr will start to flood.
    Water begins to flood some backyards of homes on the
    northside of View Dr as well as other low lying areas. Back
    Loop Rd Bridge will be closed during outburst events.

    At 12.5 feet: 2 to 4 feet of water in some backyards along
    Meander Way on the the river side of the HESCO levee.

    At 13.0 feet: The low section of road past 9374 View Dr will
    be flooded with 2 ft of water. Water begins to flow through
    some backyards of homes on the northside of View Dr and flood
    low lying areas. A few locations on View Dr will see depths
    of 1 to 2 feet of water in homes.

    At 13.5 feet: Water starts to back up behind homes between
    Riverside Dr at Tournure St and Mendenhall River School.
    Locations on River Rd with low river banks will begin to see
    water inundate yards. Severe bank erosion along unreinforced
    river banks.

    At 14.0 feet: The low section of road past 9374 View Dr will
    be significantly flooded and impassable. Water will begin to
    flow over the road from water flowing behind homes on the
    north side of View Dr. More homes along View Dr will begin to
    see moderate to major flooding. Locations on River Rd with
    low river banks will begin to see water approach driveways.

    At 15.0 feet: Major flooding of multiple homes along View Dr.
    Water will begin to approach a few homes along River Rd with
    low river banks with possible flooding of driveways and 1 to
    2 feet of water in backyards. Up to 1 foot of water covering
    Riverside Dr at Tournure St and Mendenhall River School.

    At 16.0 feet: Water starts to overtop the bank and flood low
    lying areas near Wildmeadow Ln. Up to 0.5 feet of water will
    be in the intersection of Skaters Cabin Rd and Arctic Cir.
    Some backyards of homes between Tamarack Ct and Whitewater Ct
    will start to see flood waters along with water approaching
    River Rd near homes with low river banks and possibly
    flooding those homes. Water will start to flood backyards of
    homes on Meadow Ln and Stikine St.

    At 17.0 feet: This is an estimate that water will be
    overtopping the river banks and flooding into the homes
    around Wildmeadow Ln. Businesses in the Vintage Park Blvd
    area will be surrounded and potentially inundated by flood
    waters. Homes on Meadow Ln from Stikine St to Eagle St will
    be inundated with flood water. Water will be covering
    Tournure St from Riverside Dr to Columbia Blvd. Black Wolf
    Way and Pond Vista Dr will have water across the roads. All
    parts of View Dr will be covered by flood water.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don`t drown when encountering flooded roads. Most flood
deaths occur in vehicles.

The cold water temperatures can increase the threat of hypothermia
and lower the time required to cause hypothermia.

Stay tuned to further developments by listening to your local radio,
television, or NOAA Weather Radio for further information.

&&

LAT...LON 5841 13460 5842 13460 5845 13460 5847 13456
      5846 13452 5844 13447 5843 13447 5840 13454
      5836 13459 5835 13460 5836 13462


$$

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