Scientific Forecaster Discussion
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
310 PM akdt Wednesday Jul 1 2015
Current operational model runs agree well out through 72
hours/Friday night. The major weather for this forecast cycle
continues to be the heavy rain event in the southeastern interior
and the Alaska Range.
A strong upper low centered near 54n/149w in the Gulf of Alaska
will weaken over the northwestern Panhandle by Thursday morning
as a new upper low center develops just to the north over the
southern Yukon territory. The new center will continue on eastward
into Canada Thursday afternoon into Thursday night. The southeast
interior will remain under the influence of the cyclonic
circulation aloft through Thursday.
A short wave trough aloft over the West Coast will move slowly
eastward...by Friday afternoon the trough axis will extend from
deadhorse to Ruby to Bethel. The trough will weaken through
Saturday afternoon with the axis of the weak trough remnant
extending from Old Crow to minchumina to Bethel. Any precipitation
with the short wave trough will be limited mainly to areas near
the Brooks range and northward.
At the surface...a front will approach northwest Alaska this
evening and move eastward across the Arctic slope through
Thursday while weakening. The front will bring a short period
of rain to the central and western parts of the Arctic coast
as it moves eastward.
In the extended period...GFS and European model (ecmwf) runs begin to rebuild the
upper level ridge over the Alaska Mainland Saturday and
Sunday...with the ridge sharpening and moving to near the alcan
border by the weekend. This will bring another period of very warm
temperatures over the interior...Brooks range and Arctic slope.
The 12z GFS runs develops a weak upper low burrowing eastward
into the ridge across the interior Sunday into Monday with lower
850 mb temperatures and GFS MOS temperature guidance which looks
too cool. This idea is not supported by the European model (ecmwf) or any of the
Coastal hazard potential days 3 and 4...none
wetting rains will continue through Thursday over most the
southeast interior and the Alaska Range. No red flag conditions
are expected in the short term. Much warmer and drier conditions
expected to develop over the weekend and continue into early next
week...ongoing fires in the interior will likely become much more
active with the high daytime temperatures and lower afternoon
current GFS and NAM model runs continue to indicate that
the heaviest rainfall areas will be over the northwest half of
zone 224...the western half of zone 226...zone 223...and extreme
eastern zone 225. In these areas...additional rainfall amounts
of 1 to 1.5 inches are expected through Thursday afternoon...
with local amounts up to 2 inches in extreme eastern zone 225...
most of zone 223 west of Delta Junction...and in zone 226 west
of the Richardson Highway.
The highest 24 hour rainfall totals reported as of noon today...
Denali visitor center 0.87 inches
Denali Park Airport 0.94 inches
Gold King RAWS 0.80 inches
Donnelly RAWS 0.78 inches
Salcha river hads 0.75 inches
Flood Watch for akz223-akz224.
Small stream Flood Advisory for akz223-akz224-akz225-akz226.
Dense smoke advisory for akz221.
Small Craft Advisory for pkz210-pkz220-pkz225.
Gale Warning for pkz230.
Rf Jul 15