Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
429 PM EDT Thu Jul 04 2019
Valid 12Z Mon Jul 08 2019 - 12Z Fri Jul 12 2019
...Record heat for much of South-central Alaska...
...Guidance and Predictability Assessment...
The intense blocking pattern that has been anchored over the
region the better part of the last week plus will slowly weaken
and drift to the west. This will favor the trough over the Bering
Sea to move eastward and this is supported by model guidance and
the means. As the ridge weakens, shortwave energy will ride the
top near the Beaufort Sea and send a front into north Alaska;
cooler temperatures will usher into the north and northeast by the
end of the period.
The latest GFS has maintained being the progressive solution, with
the ECWMF being close to the center of cluster. The CMC appeared
to be an outlier as it becomes out of phase with the rest of the
guidance fairly early on in the forecast period by continuing to
hold onto the ridge over parts of the mainland. Given the duration
of the current blocking pattern and its intensity, and per input
from an Alaska WFO forecaster, the evolution of the ridge may
resemble closer to the CMC than the other solutions that quickly
transition out of ridging. The ensemble meas had a better handle
on timing and placement of this pattern change than any individual
global model. The blend for this forecast period was heavy on the
ECWMF ensemble, NAEFS and GEFS means with a nudge toward the CMC.
...Weather/Threats Highlights...
For much of the extended period temperatures will be well-above
normal across portions of Alaska, particularly for the
south-central locations. Daily highs near or above 90F could
easily tie, or break records this weekend, possibly into early
next week. Precipitation chances will be limited to near the
Brooks Range and northeastern Alaska as the front moves
east/southeastward, eventually into the Panhandle as the front
dips southward. Critical fire weather conditions are expected to
continue over a vast portion of the central and southern/southeast
Alaska as the hot and dry conditions prevail.
Campbell
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
- Enhanced wildfire risk across portions of mainland Alaska,
Sun-Thu, Jul 7-Jul 11.
- Enhanced wildfire risk across portions of the Alaska Panhandle,
Sun, Jul 7.
- Much above normal temperatures across portions of mainland
Alaska, Sun-Thu, Jul 7-Jul 11.
- Much above normal temperatures across portions of the Alaska
Panhandle, Sun, Jul 7.
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