313
FNAK71 PAFC 132158
FWSAER

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

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

.DISCUSSION...

The streamflow assessment from August 12 remains on track:
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 this afternoon and evening with just a
chance of rain on Thursday. This rainfall will be light and is
not expected to impact water levels significantly. Historically,
Twentymile River water levels have not receded from August baseflow
until mid-end of September.

Weather conditions:
Thursday morning will start out dry with light winds and fairly
high ceilings. There is just a slight chance of patchy fog/few low
clouds in the vicinity of Turnagain Arm. A weak upper level
disturbance will lead to lowering ceilings Thursday afternoon
along with a chance of rain, but flying conditions should remain
VFR.


.THURSDAY...

Sky/weather.........Mostly cloudy (75-85 percent). Slight chance of
                    rain in the morning, then chance of rain in the
                    afternoon.
Chance of pcpn......40 percent.
Max temperature.....Around 54.
Surface winds (mph).Light winds.
Rainfall amount.....0.01 inches.
CEILING (KFT).......6,000 to 10,000 feet in the morning, dropping to
                    4,500 to 6,000 feet in the late afternoon.
Visibility..........10SM.
SUNSET..............955 PM.

$$
Forecaster...Baines
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