Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
337 PM EDT Mon Oct 28 2019
Valid 12Z Fri Nov 01 2019 - 12Z Tue Nov 05 2019
Upper ridging is forecast to remain just south of the Gulf of
Alaska late this week through next weekend as additional ridging
moves through the Bering Sea into western Alaska. This will favor
troughing moving from southwestern Alaska towards the Panhandle.
This brings a surface low into southwestern Alaska where it
weakens, while a stationary front lingers across the Gulf atop the
upper ridging to its south. By early next week, upper level
troughing moving along the southern coast into the Panhandle may
try to slowly push the front southward to the southern Panhandle
region. There was good model agreement with this evolution so a
general model blend sufficed for this system, with slight
weighting towards the ECMWF given its better run to run
continuity. Across the North Slope, models show some timing
differences on troughing moving through the region mid to late
period, with the ECMWF a bit faster than the GFS and the ensemble
means. Shortwave energy rounding the base of a closed low in
eastern Russia sends a surface low towards the western
Bering/Aleutians. Trended towards the ensemble means with this
system just given normal timing/intensity differences at the
longer lead time.
Rain/snow will spread across the Alaska Peninsula and Southcentral
into southeastern areas later in the week as the lead Pacific
front makes steady progress eastward. Precipitation will linger
over the Panhandle with WSW flow aloft around the stationary
frontal boundary. The next Bering system should bring another
round of rain to portions of the western Aleutians.
Santorelli
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
- Heavy precipitation across portions of the Alaska Panhandle and
mainland Alaska, Thu, Oct 31.
- Heavy precipitation across portions of the Alaska Panhandle,
Fri, Nov 1.
- Much above normal temperatures across portions of mainland
Alaska, Thu, Oct 31
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