Scientific Forecaster Discussion
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
312 PM akdt Monday Jun 1 2015
aloft...high over the northern Chukchi Sea with a low over the
Canadian Arctic. The high will drift southwest and weaken through
the week. Strong short wave trough from Eagle to Delta Junction to
the Seward Peninsula will weaken and dissipate from Northway to
the Yukon Delta by 4am Tuesday. A second short wave trough moving
south to the eastern Arctic coast 4am Tuesday then extending from
Barter Island to a low near Anaktuvuk Pass to Bethel 4am Wednesday. The
low and southwestward trough will drift west to extend from
Prudhoe Bay to the Yukon Delta 4pm Thursday. The flow aloft over the
southeast interior will become southwest Tuesday then transition to
south then southeast as this trough west. Northerly flow
persisting northwest of the trough.
Surface...1037 mb high northwest of Barrow drifting southeast and
weakening near the russian Arctic coast through Thursday. Cold front
from 30 miles north of Northway to just south of Denali park
drifting south overnight and weakening. Weak thermal tough from
Aniak to Scammon Bay moving south overnight.
Models...agree fairly well in the short term with the transitions
from col flow over the eastern interior to a returning moist southwest
and warmer scenario later Tuesday into Wednesday...then to southeast flow
and warmer. The forecast by all models for precipitation over the north
side of the eastern Alaska Range later Tuesday into Wednesday night seems
overdone as this should be in the rain shadow though flow is
somewhat light. The drift of the second short wave over the
central interior westward over time is favored by all. In medium
term quite a variance in the pattern aloft over northwest Alaska
between the European model (ecmwf) and GFS.
North Slope...a round of snow moving over the area later tonight
and into Tuesday with second short wave trough dropping south. Expects
an inch of snow over the 3 eastern zones...lesser amounts to the
west. Scattered snow showers lingering near Brooks range through
Thursday as upper trough drifts west over the area. Gusty northeast
winds as well for a while into Tuesday as short wave moves through.
Temperatures remaining on the cool side through the middle of the
Western Alaska...limited convective activity over the southern
Yukon Delta zone tonight before thermal trough moves south. As
second short wave trough elongates southwest over interior area
and then drifts west...expect the southwest flow to bring some
rain showers to the upper Kuskokwim valley Wednesday which will spread
west over the lower Yukon valley and middle Yukon valleys Wednesday
night and Thursday. Expect dry conditions farther west.
Central and eastern interior...scattered rain and areas of snow
southeast of Fairbanks will taper off this evening. Clearing and
cooler temperatures remaining overnight will produce areas of
frost in low lying area protected by the northeast winds. The
winds will trend downward as the cold front dissipates overnight
so northeast winds will be lighter on Tuesday. Expect overrunning
rain showers to break out late Tuesday into Wednesday from Denali park to
Fairbanks to Eagle as southwest flow develops. Areas of rain or
showers diminishing in extent Wednesday night and Thursday and moving to the
north and west as south to southeast flow sets in with upper
trough drifting farther west.
Coastal hazard days 3 and 4...none.
Fire weather...very dry airmass behind the front continues to
move south over the eastern interior...but relative humidity will
remain above 15 percent Tuesday and Wednesday. Gusty winds will
diminish later tonight and do not anticipate extending them. Out
west same story as winds will diminish but relative humidity will
dip below 30 percent during the afternoon and evening hours.
Slight chance of thunder this evening south of Marshall...Tuesday
a slight chance of thunder south of Chicken. Thermal trough will
gradually slide back to the north and be over the interior middle
Fire Weather Watch for akz208-akz210-akz212-akz214-akz216-akz217-
Red flag warning for akz208-akz212-akz215-akz216-akz217-akz218-
Frost advisory for akz222.
Small Craft Advisory for pkz200-pkz210-pkz220-pkz230.
Brisk Wind Advisory for pkz225.
Jl Jun 15