Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
428 PM EDT Tue Sep 17 2019
Valid 12Z Sat Sep 21 2019 - 12Z Wed Sep 25 2019
Active pattern will continue for Alaska this weekend into next
week. Lead system will push through the Panhandle Saturday then
quickly into Canada. Next system is forecast to trek near (just
south of) the Aleutians Sunday and into the Gulf Monday. Consensus
of the deterministic models was used to take the low (and perhaps
triple point) into the Gulf. GFS was a bit slower than the ECMWF
and most ensembles, so trended toward that quicker consensus based
on better continuity/agreement. Locally heavy rain will be
possible along the coast from the eastern Kenai to Yakutat. Parent
low will slowly dissipate in the Gulf thereafter, maintaining a
rather wet period for the Panhandle and Southeast coast. Lastly,
another system will enter the Bering around midweek next week,
though its details were highly uncertain as it may be a
combination of tropical moisture (or an organized low) with a
northern stream system, both of which will likely change in
forward speed over the next few days.
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
Hazards:
- Heavy rain across portions of the Alaska Panhandle and mainland
Alaska, Fri-Sat, Sep 20-Sep 21 and Mon-Tue, Sep 23-Sep 24.
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