867
FNUS28 KWNS 162143
FWDD38

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0441 PM CDT Sun Aug 16 2026

Valid 181200Z - 241200Z

...Synopsis...
Mid/upper troughing near the West Coast will wane as the upper ridge
across the central US retrogrades westward, allowing drier
conditions to infiltrate much of the northwestern CONUS. Embedded
mid-level shortwaves riding along the expanding upper ridge could
bring isolated thunderstorms to portions of the Northern Rockies,
while also promoting dry and breezy conditions east of the Cascades
into the northern Great Basin. Extended guidance indicates a pattern
shift late week as eastern Pacific troughing impinges upon the
Northwest, bringing additional fire weather concerns.

...Day 3/Tuesday...
...Southern Plains...
Expanding drought and continued above normal 100+ F temperatures
will likely stay in place this week across portions of the Southern
Plains. Increasing southerly winds are expected to evolve south of a
nascent Central Plains surface low/trough over portions of northwest
TX and western OK. South winds of 15-20 mph collocated with low
afternoon RH will bring enhanced fire weather concerns to the area
on Day 3/Tuesday. Day 2/Monday rainfall potential may lead to
adjustments of the outlined region, though widespread accumulating
precipitation is not forecast.

...Portions of the Columbia Basin...
A split-flow regime consisting of west-northwesterly flow over
northern WA and southwesterly flow over Oregon will increase winds
in gap flow and terrain favored areas east of the Cascades on Day
3/Tuesday. RH values should decrease to 25% or less amid enhanced
wind gusts of 25-30 mph within an environment that did not receive
accumulating rainfall, despite preceding days of thunderstorm
activity. 40% Critical probabilities were maintained to account for
this threat.

...Days 5-7/Thursday-Saturday...
...Northwest CONUS...
As upper ridging expands into the Great Basin late week, an upper
low will progress towards the West Coast and introduce stronger
south-southwesterly flow over the Pacific Northwest. Despite some
differences in extended guidance, the evolution of upper troughing
depicts a favorable pattern for dry and breezy conditions to overlap
very dry fuels across northeastern CA, southern OR, and northwestern
NV; thus, 40% Critical probabilities were maintained on Days
5-6/Thursday-Friday.

Ensemble clusters show agreement for troughing to persist over the
Pacific Northwest through Day 7/Saturday, with enhanced southerly
flow aloft and a tightening surface pressure gradient compelling a
favorable setup for expansive critical fire weather conditions. 40%
Critical probabilities were introduced across the region, though
they may need to be confined in future outlook cycles as
moisture/thunderstorm chances are better resolved. In addition,
embedded disturbances within the troughing pattern may increase
thunderstorm potential as monsoonal moisture advects northward;
however, too much ambiguity in the overlap of sufficient moisture,
instability, and large-scale ascent precludes dry thunderstorm
probabilities at this time.

..Elizalde-Garcia.. 08/16/2026

...Please see www.spc.noaa.gov/fire for graphic product...

$$