Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
259 PM EDT Fri May 10 2019
Valid 12Z Tue May 14 2019 - 12Z Sat May 18 2019
Upper ridging near the Sakhalin Oblast, the Canadian
Archipelago/Northeastern Alaska, and just north of Hawai'i will
favor troughing in between, roughly along 50N. Several
smaller-scale features will wobble/rotate around/through the mean
trough which limits predictability in the details, but was
otherwise predictable at longer wavelengths. The 06Z GEFS mean was
an exception as it made an adjustment away from its 00Z run that
was rather agreeable with the 00Z ECMWF ensemble mean. The 12Z GFS
and 00Z ECMWF mostly agreed overall aside from the start of the
period when the GFS was still a bit displaced to the northeast
with the system south of the Aleutians. The 00Z UKMET was a better
fit there. For Thu-Sat, the 12Z GFS came back into the cluster
near the 00Z GEFS mean/ECMWF/ECMWF ensemble mean which carried low
pressure eastward south of the Gulf toward Hadai Gwaii next
weekend. This favors fairly dry conditions for much of the
interior portions with rain/snow chances along the
Aleutians/Panhandle with lesser amounts into Southcentral.
Fracasso
Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
No significant hazards are expected over Alaska during this
forecast period.
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