Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
555 am akdt Sat Jul 23 2016


Upper air...
a weak trough extending from the eastern Beaufort Sea to the Chukchi
Sea move southward to extend from inuvik to Kuskokwim Bay by late
tonight. By late Sunday night the trough will extend from the
MacKenzie river Delta Region to the Alaska Peninsula with a low
center developing over Bristol Bay. The low will split off from
the main trough Monday morning and move to south of the Alaska
Peninsula by late Monday night. The northern portion of the trough
will weaken and transition into a light westerly flow pattern over
the northern interior and northward by Monday evening. Current
model runs from the Jul 23/00z forecast cycle are in good agreement
out through Monday night.

a 996 mb low over the northern Gulf of Alaska will weaken into
a trough late this afternoon as a new 997 mb low develops about
150 nm east of Northway. By Sunday morning the pattern will morph
into an area of broad low pressure over south central Alaska and
the Kenai Peninsula with a narrow trough extending eastward to
Northway into the Yukon territory. A 1021 mb high centered 400 nm
north northwest of Barrow will weaken to a 1017 mb high centered
400 nm north of the MacKenzie river Delta by Monday afternoon.
Weak low pressure will expand northward across the interior
and Brooks range by Monday afternoon.

Central and eastern interior...
today and tonight...isolated afternoon and evening thunderstorms
in the upper Koyukuk valley-central interior-middle Tanana
Valley-upper Yukon valley and fortymile country-southern uplands of
the upper Yukon valley. Showers most areas except the northeast
interior through this evening tapering off later tonight.
Sunday and Sunday night...isolated afternoon and evening
thunderstorms in and near the Alaska Range. Showers along and near
the Alaska Range.

Western interior...
today and tonight...isolated afternoon and evening thunderstorms
in the lower Koyukuk and middle Yukon valleys-lower Yukon valley.
Showers over most areas today tapering off tonight.
Sunday and Sunday night...isolated afternoon and evening
thunderstorms in the middle Yukon valley-lower Yukon valley-upper
Kuskokwim valley. Numerous to widespread showers over the Alaska
Range and mainly scattered showers in areas just to the north of
the Alaska Range. Scattered showers over most areas in the
afternoon and in the southern areas in the evening mainly
dissipating after midnight.

West Coast...
rain or showers from the Seward Peninsula south today
tapering off by late tonight.

Arctic coast...
sky cover will continue to be mainly diurnal, with mostly cloudy
skies with areas of fog at night and in the morning becoming
mostly sunny in the afternoon. Some rain showers over the
northeastern Brooks range today through Sunday.

Extended outlook...
current models suggest a predominantly wet pattern with near
to below normal temperatures over most areas except the
southeast interior where temperatures may average a bit
above normal.

Coastal hazard potential days 3 and 4...none.


Fire weather...
minimum humidities of around 28-38 percent expected in the
Noatak valley and the northeastern interior today and Sunday.
Elsewhere minimum humidities are expected to remain above
40 percent. Maximum humidities are expected to be 80 percent
or higher. Interior winds will remain light.


the chena river at Two Rivers crested at 1.3 feet above minor flood
stage Friday morning and has now fallen to 0.5 feet above minor
flood stage, and will continue to fall through Monday. Flow of the
chena river through Fairbanks continues to be regulated by the
Moose Creek dam with the stage at Fairbanks remaining steady
around 8.8 feet. The little chena river crested at 21.4 feet
Friday morning and is now falling slowly. The Salcha river at the
Richardson Highway bridge has crested at minor flood stage
of 14.0 feet and is no starting to fall. The Chatanika river is
remaining nearly steady below action stage and is expected to
begin to fall slowly later today. The Tanana river is continuing
to rise slowly at Fairbanks and Nenana. Tanana river is expected
to crest just below the minor flood stage of 12.5 feet Sunday
night. Small rivers and streams in western Denali park are likely
still at high levels but are expected to begin falling slowly
today. Showers are expected over much of the interior through
tonight with most areas likely receiving less than 0.25 inch.
Current GFS and NAM model runs indicate potential for heavier
rainfall in the Alaska Range Sunday and Sunday night, with amounts
of 0.5 to 1.0 inch possible which could cause a rise in The Levels
of small rivers and streams.


Afg watches/warnings/advisories...
Small Craft Advisory for pkz220-pkz225-pkz240-pkz245.


Rf Jul 16

National Weather Service Glossary of Abbreviations