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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 050608
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0108 AM CDT Sun Jul 05 2026
Valid 051200Z - 061200Z
...Synopsis...
Dry thunderstorms will pose a fire weather risk today across
portions of the Pacific Northwest and Southwest. Recent upper-air
analyses show steady amplification of an upper ridge over the
greater Four Corners region. This will maintain very dry and warm
conditions for much of the western CONUS, but should generally limit
surface pressure gradient winds. However, very dry low-level
conditions coupled with an influx of mid-level moisture will support
thermodynamic profiles favorable for dry thunderstorms across
portions of the West.
...Northern California into Oregon and Nevada...
A shortwave trough embedded within the mean south/southwesterly
upper-level flow is noted in water-vapor imagery along the CA coast.
This feature will continue to move northeast towards southern OR
through today. A modest influx of mid-level moisture attendant to
the wave coupled with weak ascent should support adequate buoyancy
for thunderstorms from northern CA into OR and adjacent portions of
northwest NV/southwest ID. Very dry boundary-layer conditions noted
in 00 UTC soundings should modulate rainfall amounts and favor dry
thunderstorms. Confidence in dry lightning potential is greatest
across southern OR where recent fuel reports suggest fuels are
becoming increasingly receptive and lightning ignitions will be
possible.
...Southwest...
Early-morning GOES PWAT estimates depicts a plume of 0.75-1.25 inch
PWAT values advecting northward from Baja California. The eastern
fringe of this moist plume will spread across AZ and far western NM
through the day where lapse rates remain very steep from the surface
through around 6 km based on regional 00 UTC soundings. Model
guidance continues to suggest that mid-level moistening will be
sufficient to support enough buoyancy for high-based convection by
late afternoon. With LCL heights forecast to be around 3 km,
thermodynamic profiles will be favorable for dry lightning strikes
from eastern AZ into NM and south-central CO. Confidence in dry
thunderstorm potential remains highest across eastern AZ into
southwest NM, but recent CAM ensemble guidance has trended towards
higher probabilities for convection across southern CO to the west
of the Front Range where conditions remain very dry and active fires
have been ongoing. Some guidance hints that very isolated
thunderstorms are possible as far west as central AZ along the
Mogollon Rim, but ensemble support remains too limited to warrant a
westward expansion.
...Southern Montana...
Additional dry thunderstorms appear possible across southern to
southwest Montana this afternoon as weak upper perturbations crest
the apex of the upper ridge. Despite a fairly strong convective
signal in latest ensemble guidance and forecast soundings depicting
dry boundary-layer conditions, recent rainfall should limit fuel
status for the time being.
..Moore.. 07/05/2026
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 050644
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0144 AM CDT Sun Jul 05 2026
Valid 061200Z - 071200Z
...Synopsis...
Fire weather concerns will continue across parts of the Southwest,
Great Basin, and Pacific Northwest on Monday - largely driven by dry
thunderstorm concerns.
...Pacific Northwest into the Four Corners...
Short-range guidance continues to show persistent upper ridging over
the Four Corners into the early week. Continued north/northeastward
advection of mid-level moisture into a plume of steep mid-level
lapse rates will result in a broad fetch from the Pacific Northwest
into the Four Corners with adequate buoyancy for weak convection,
PWAT values between 0.5 to 0.75 inches, and very dry boundary-layer
conditions. Confidence in thunderstorm occurrence remains highest
across northern CA/NV into adjacent portions of OR and ID where a
slow-moving shortwave trough will focus ascent. More isolated
thunderstorms will be possible with southeastward extent into the
Four Corners region and will likely be driven primarily by localized
orographic ascent. Across both regions, thermodynamic profiles will
largely favor dry lightning, but 10-15 knot storm motions may allow
for pockets of wetting rainfall. Regardless, receptive fuels will
support some concern for lightning ignitions - especially across the
Four Corners where conditions remain very dry.
...Southeast Nevada into Utah and Arizona...
The development of a weak surface low over the northern Great Basin
will likely support a swath of sustained winds near 15 mph from
southern NV into central UT and northern AZ. With a dry air mass
already in place and little to no low-level moisture recovery
expected, RH minimums will likely fall into the teens Monday
afternoon. Although variance among deterministic solutions remains
somewhat high regarding the coverage of 15 mph winds, recent
high-res ensemble guidance suggests a corridor of sustained elevated
conditions may emerge from southeast NV into adjacent portions of UT
and AZ.
..Moore.. 07/05/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 042152
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0452 PM CDT Sat Jul 04 2026
Valid 061200Z - 121200Z
Upper-level heights will build over the greater Four Corners region
and the Plains with a Four Corners high developing. Mid-level
moisture will stream northward into the Intermountain West amid
south-southwest flow aloft, with deeper moisture moving into
southern Arizona and portions of New Mexico. An upper-level trough
is expected to move into the northwest US mid-week, but there is
uncertainty regarding its strength and timing. Additionally, the
Four Corners high is likely to flatten and drift westward mid to
late next week.
A broad area of isolated mixed wet/dry thunderstorms is likely on
Day 3/Monday stretching from Oregon to the Four Corners. PWAT values
0.5-0.9 with storm motions of 10-20 knots above a dry, deep
sub-cloud layer are expected across this expansive area. Fuels are
receptive, especially across the Four Corners states into
central/eastern Nevada where ERC values are mostly at 90th-97th+
percentiles. The presence and timing of waves rotating through the
southwest flow aloft and evolution of the mid-level moisture may
require adjusting this area in subsequent outlooks.
Isolated to scattered mixed wet/dry thunderstorms are likely again
on Day 4/Tuesday with a focus on the greater Four Corners region.
The upper high will likely suppress convection in parts of the 10%
area, but storms are likely to be wetter farther to the east and
south of the high. Additionally, mixed wet/dry thunderstorms may
develop over receptive fuels across portions of central/northeast
Nevada into northern Utah.
Dry and breezy conditions are likely Day 4/Tuesday across the
Cascade Gaps extending into northeast California and northwest
Nevada ahead of the upper-level trough moving into the Northwest. A
40% area was introduced to reflect these forecast conditions.
Additional 40% areas were considered across portions of the Great
Basin into the Four Corners Day 4/Tuesday - Day 6/Thursday. However,
the forecast uncertainty regarding the strength and track of the
upper-level trough across the northwest US mid to late next week
precluded introducing additional 40% areas.
..Nauslar.. 07/04/2026
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