Juneau, AK Severe Weather Alertstar_ratehome

...FLOOD WARNING FOR A GLACIER-DAMMED LAKE OUTBURST REMAINS IN EFFECT
UNTIL 430 AM AKDT FRIDAY...

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

* WHERE...The Mendenhall Lake And River near the Mendenhall Glacier
Recreation area, View Drive and below Back Loop bridge.

* WHEN...Until 430 AM AKDT Friday.

* IMPACTS...Flooding of the area around Mendenhall Lake and along the
Mendenhall River is ongoing. Water levels will continue to rise
through Thursday morning while water temperatures will fall within
the lake and river.

* ADDITIONAL DETAILS...
- At 115 AM AKDT, gauge data reported a glacier-dammed lake
outburst is ongoing. Flooding is ongoing 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 1:15am the stage was 10 feet and rising, entering Moderate
Flood Stage. Water levels will go above major flood stage around
9:00am Thursday. A crest between 16.1 and 16.6 feet is expected
between 11am and 3pm Thursday.

Impacts:
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 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 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 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 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...

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

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

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

&&

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON THURSDAY TO 7 PM AKDT
FRIDAY...

* WHAT...Temperatures in the lower 80s expected.

* WHERE...City and Borough of Juneau and Eastern Chichagof Island.

* WHEN...From noon Thursday to 7 PM AKDT Friday.

* IMPACTS...Individuals not accustomed to these unusually hot
temperatures for this region may experience heat related illnesses.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, and check up on elderly and vulnerable
relatives and neighbors.

&&

...POSSIBLE DEBRIS IN WATER...

The Mendenhall River is experiencing a glacier lake outburst
flood and as a result of the release, debris in the water remains
possible on the Mendenhall River, extending down into Stephens
Passage, Fritz Cove, and Favorite Channel through Friday morning.
Caution is advised for mariners and all recreational users on the
water for hazards to their vessels.