Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
321 PM EDT Tue May 07 2019
Valid 12Z Sat May 11 2019 - 12Z Wed May 15 2019
Models and ensembles still show a well established blocky flow
pattern for the next week highlighted aloft by a closed and high
amplitude Bering Sea trough extending across the Aleutians into
the north Pacific and resultant high amplitude ridge centered over
the northeast Pacific and southeast/eastern Alaska.
Despite reasonably similar larger scale flow depictions, guidance
solutions diverge through this forecast period with the timing and
placement of vortices rotating around the Bering Sea trough and
resultant placement of lows in the Bering/northern Pacific and
adjacent Gulf of AK and southwestern AK. Perhaps the best guidance
clustering is with respect to the potential formation and slow
approach of a deepened low to the south of the Aleutians early to
mid next week.
Overall, the WPC Alaskan medium range product suite was primarily
derived from a 50-50 blend of the compatable 12 UTC GEFS mean and
00 UTC ECMWF ensemble mean.
Schichtel
Bullet points from the WPC Days 3-7 Hazards chart can be found at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
-- Heavy precipitation across portions of southern mainland
Alaska, Fri, May 10.
WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can also be
found at:
https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml
https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html