HAZMAT Decision Support Page

966
FNAK71 PAFC 131459
FWSAER

Spot Forecast for 20 Mile Avalanche (AK25020258)...AMRG
National Weather Service Anchorage AK
659 AM AKDT Wed Aug 13 2025

Forecast is based on forecast start time of 0600 AKDT on August 13.

.DISCUSSION...

STREAMFLOW ASSESSMENT:
The Twentymile River is expected to be near its median flow. We
estimate that overall water levels should slightly recede between
Wednesday and Sunday, but by less than 1 foot. Minor rainfall is
expected for the region Wednesday into Thursday, but not expected
to impact water levels significantly. Historically Twentymile
River water levels have not receded from August baseflow until
mid-end of September.

METEOROLOGICAL CONDITIONS:
Clouds are building in as an upper level through moves in from the
west. Precipitation chances increase today, with a period of light
rain likely late this afternoon through early this evening. Winds
in the Twentymile valley are expected to be light into the weekend.

.TODAY...

Sky/weather.........Mostly cloudy (80-90 percent). Rain likely in the
late afternoon.
Chance of pcpn......60 percent.
Max temperature.....Around 53.
Surface winds (mph).East winds 3 to 6 mph.
Rainfall amount.....0.05 inches.
CEILING (KFT).......15,000 feet early this morning, dropping to 5,000
feet this afternoon.
Visibility..........10SM.
SUNSET..............9:55pm

$$
Forecaster...Jones
Requested by...Amy Holman
Type of request...SAR
.TAG 2519772.1/AER
.DELDT 08/13/25
.FormatterVersion 2.0.0
.EMAIL amy.holman.ak@gmail.com