Alaska Extended Forecast Discussion
National Weather Service College Park MD
657 PM EDT Thu Jul 3 2025

Valid 12Z Mon 07 Jul 2025 - 12Z Fri 11 Jul 2025

...Ongoing hazardous heat across Northern Alaska Sunday moderates
into Monday...

...Heavy rain likely across the southern Panhandle on Tuesday...

...Synoptic Overview...

The heat wave across northern Alaska through the 4th of July
weekend will abate on Monday and promptly reverse to a cooler than
normal temperature regime across that portion of Alaska through
the remainder of the upcoming workweek. A strong rex block
resulting in anomalously strong ridging aloft across northern
Alaska will break down as a sharp trough digs southward from the
Arctic Ocean Monday. The trough will expand southwestward,
becoming positively tilted, while stalling across northern and
western Alaska through the rest of the workweek, allowing cooler
than normal temperatures to persist across much of western Alaska
as well. This positively tilted trough pattern will guide multiple
upper level lows embedded in the subtropical jet over the north
Pacific northeastward into the Gulf and into the Panhandle. This
will make for rainy periods on Tuesday and potentially again on
Friday in the Panhandle, with relative breaks in the rainfall on
the days in between. Onshore flow through the period should keep
things cloudy across much of the state, including the Panhandle.

...Guidance Evaluation and Preferences...

While the upper level pattern will be active for this time of
year, the guidance remains as normal...generally in agreement
through Day 5/Tuesday, then rapidly disagreeing into the end of
the week. The disagreements generally stem from differences in how
quickly any subtropical disturbances track into the Panhandle, as
well as how deep the northern and western Alaska trough gets. Due
to these disagreements, a standard model blend was used. No
obvious standout models among the primary 3 (CMC, GFS, EC) were
noted, so a blend of the 3 was used for Days 4 and 5 (Mon and
Tue), followed by a gradual blending towards the ensembles by Day
8/Fri. Since the ensembles all still had the general pattern
described above well-portrayed, a small remnant of the
deterministics was left in the blend to hint at more details by
the longer-range period.

...Weather/Hazards Highlights...

Hazardous heat is expected to continue into Sunday across much of
northern Alaska, the final day of a multiple-day heat wave for the
4th of July weekend. Temperatures south of the Brooks Range are
expected to soar well into the 80s, perhaps near 90 in a few
isolated areas on Sunday. As an Arctic trough moves in on Monday,
the heat will abate significantly on Monday, with the warmest
temperatures near 80 possible in northeast Alaska south of the
Brooks Range. In coordination with AFG/Fairbanks, AK WFO, the
Hazardous Heat timing was trimmed to just Sunday July 6, and left
out of Monday due to the aforementioned cooling expected on
Monday.

Heavy rain from a potent low in the subtropical jet is likely to
impact the southern Panhandle on Tuesday. The low center will
track across the northeastern Panhandle and into the Yukon,
leaving a prolonged period of onshore and upslope southwesterly
flow off the Pacific for the southern Panhandle. This will result
in rainfall totals of 2-3 inches for the Tuesday and Tuesday
night period, with lesser amounts both Monday night and Wednesday.

&&

Wegman



Additional 3-7 Day Hazard Information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

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