|
U.S. & Canada 00-UTC 48 Hour Surface Smoke Forecast
Map is in operation from early April through October 31
U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 091623
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1123 AM CDT Sat May 09 2026
Valid 091700Z - 101200Z
...Northern Plains...
Existing elevated fire weather highlights over much of western ND
were expanded southward towards the ND/SD border based on latest
short term forecast guidance. Sustained northwest winds of 15-20 mph
in a modestly dry (RH between 20-30% by this afternoon) post-frontal
environment should yield several hours of elevated fire weather
conditions for far northeastern MT and much of western ND southward
to the ND/SD border. Fuels remain very dry and supportive of
wildfire growth, despite the cooler post-frontal air mass
infiltrating into the Northern Plains. Otherwise, the forecast
remains largely on track, please see previous discussion for more
details.
..Williams.. 05/09/2026
.PREV DISCUSSION... /ISSUED 0158 AM CDT Sat May 09 2026/
...Synopsis...
Between a large-scale ridge over the West Coast and broad upper
troughing over the eastern two-thirds of the CONUS, a belt of
enhanced deep-layer northwesterly flow will overspread a dry
post-frontal air mass over the northern Plains. Over parts of
western/central ND, diurnal heating will result in a well-mixed
boundary layer with 20-30 percent RH amid 15-20 mph sustained
northwesterly surface winds. This overlap of modestly dry/breezy
conditions over critically dry/receptive fuels will favor elevated
fire-weather conditions. The Elevated highlights are generally
bounded by cooler temperatures/higher RH to the east, expected cloud
coverage to the west (accompanying a passing shortwave trough), and
a band of ongoing precipitation across southern ND.
Farther west, areas of dry/windy conditions are expected across
parts of the Great Basin into the Southwest. While locally elevated
conditions will be possible, fuels are generally unsupportive of
large fires at this time.
|
U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 091935
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0235 PM CDT Sat May 09 2026
Valid 101200Z - 111200Z
...NO CRITICAL AREAS...
...Southwest and Great Basin...
Dry conditions including minimum surface RH of 5-15% by peak
afternoon heating are expected across much of the Southwest (west of
the Continental Divide) and Great Basin Sunday. A deeply mixed
boundary layer will evolve under a building upper ridge by Sunday
afternoon. However, overall surface winds will be rather light amid
a diffuse pressure gradient field, limiting a broader fire weather
threat across the region. No changes to the previous outlook were
necessary.
..Williams.. 05/09/2026
.PREV DISCUSSION... /ISSUED 0158 AM CDT Sat May 09 2026/
...Synopsis...
A limited overlap of warm, dry, and breezy conditions atop receptive
fuels will limit fire-weather concerns on Sunday.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 092111
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0411 PM CDT Sat May 09 2026
Valid 111200Z - 171200Z
...Synopsis...
An embedded mid-level short wave rounding the apex of an established
ridge across the western U.S., moves into MT Day 3/Monday while
broader upper-level troughing deepens over the Northeast. Dry,
post-frontal flow under stronger northwest winds aloft should bring
a continued fire weather threat to portions of the Northern Plains
and Upper Midwest on Days 3-4/Monday-Tuesday. The upper ridge over
the Intermountain West begins to shift east midweek while an upper
trough moves into the West Coast. This should usher in increasing
mid/upper-level moisture and high-based thunderstorm potential for
the Southwest/Colorado River Basin as well as stronger
south/southwest winds into the Great Basin. Dry conditions will
likely return to the much of the late next week across much of the
Southwest.
...Day 3/Monday - Northern High Plains...
Dry, post-frontal flow from the northwest atop receptive fuels will
increase fire weather concerns across much eastern MT and western
Dakotas on Day 3/Monday. Northwest winds of 15-20 mph aligning with
modest RH reductions close to 20% are likely, with a minor eastward
expansion of the existing 40% critical probabilities into western ND
and far northwestern SD base on latest forecast guidance.
...Day 4/Tuesday - Portions of Northern Plains and Upper Midwest...
A cold front extending southwestward from a parent low in the Great
Lakes should move into the Upper Midwest by Day 4/Tuesday. Northwest
winds of 15-20 mph behind the front will impact portions of the
Dakotas, southwest MN and northwestern IA. Precipitation associated
with the cold front and related upper short wave should be displaced
to the east, allowing very dry fuels to remain in place. 40%
critical probabilities have been introduced into the eastern
portions of the Dakotas, southwest MN and northwest IA.
...Day 5/Wednesday - Great Basin...
A pronounced upper trough and associated increasing southwesterly
flow enters the Western U.S. on Day 4/Wednesday. Stronger southwest
winds of 20-30 mph and low RH are likely to align across much of the
eastern Great Basin and Desert Southwest. Temperatures well above
normal and dry conditions under a dominating upper ridge leading up
to this wind event should contribute to drying and curing of fuels,
particularly in east-central NV and southwest UT where 40% critical
probabilities have been added. In addition, increasing
mid/upper-level moisture ahead of the trough and daytime heating
could generate high-based showers and thunderstorms across higher
terrain of the Southwest and CO River Basin. However, ample cloud
cover could reduce overall instability limiting thunderstorm
development, although concerns remain for at least a few lightning
ignitions as dry and breezy conditions return for the latter part of
next week. Uncertainty in expected cloud cover precludes
introductions of dry thunderstorm probabilities at this time.
..Williams.. 05/09/2026
|
