Uitleg wetenschappelijke weersvoorspelling
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
406 PM akst sun Nov 23 2014
the old low surface/aloft centered over the Alaska Peninsula will
continue to fill...with a second weak center aloft over northwest
Mainland Alaska becoming the predominant center. This one in turn
moves east on Tuesday as ridging aloft builds over Mainland Alaska
again ahead of the developments in the Bering Sea discussed
below. Expect a small...about 1012 mb...surface low to develop
near Demarcation Point Monday night as the associated trough aloft
moves into place to support it.
Significant differences among the models appear as we get closer
to mid-week. The 12z GFS departed noticeably from the previous
model consensus in developing a fairly deep low over the North
Pacific on the trailing front associated with the Bering Sea
system...then moving it cyclonically northeast...north and
northwest over the Bering Sea. Though the 981 mb center did pass
west of Saint Matthew Island Wednesday morning before it turned
northwest before it turned northwest and began to weaken...the
weather front associated with it would give at least zones 211...
213...and 214 a decent shot of precipitation. The 18z GFS run
is similar...though the center is not quite as deep...it is
somewhat more generous with the precipitation. The current NAM
run is even deeper...and recent GFS runs are definitely on the
deep end of the sref spectrum concerning this feature. The ecmf
keeps most of the energy over the western Bering Sea...it shows
a similar development over the North Pacific...but moves it more
easterly...cuts it off...and fills it up south of the Alaska
Peninsula. We have compromised by bringing south winds up to
a minimum Small Craft Advisory for area 210 on Wednesday...with
a chance of snow in 211...213...and 214 Tuesday night and
Coastal hazard potential days 3 and 4...none
heavy freezing spray warning for pkz200-pkz210-pkz225.
Small Craft Advisory for pkz210.
Brisk Wind Advisory for pkz245.
Djh Nov 14