U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 200548
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1248 AM CDT Sun Jul 20 2025
Valid 201200Z - 211200Z
...Synopsis...
An upper-level trough will begin to sag into northern California and
the northern Great Basin today. A surface trough will develop from
the Northwest into the central Great Basin.
Elevated to locally critical conditions are possible from northern
Nevada into the Snake River Plain and western Wyoming. RH will be
lowest in Nevada where 10-20% is expected. Farther north and east,
15-20% will be more common. Surface wind speeds will generally range
from 15-20 mph in most locations. With some terrain enhancement in
the Snake River Plain, there is some potential for briefly stronger
winds. This location has a greater probability for sustained
critical conditions, though ensemble guidance continues to suggest
it will remain quite localized.
..Wendt.. 07/20/2025
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 200549
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1249 AM CDT Sun Jul 20 2025
Valid 211200Z - 221200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHWEST NEVADA...
...Synopsis...
The upper-level trough in the Northwest will continue to dig
southward through the day on Monday. Some increase in the mid-level
jet is expected to occur from northwest Nevada into the northern
Rockies. A surface low will deepen in the northern Great Basin.
...Central/northern Great Basin into western Wyoming...
A broad area of elevated fire weather conditions are expected across
these regions. Surface winds will reach 15-20 mph in most locations,
though areas of higher speeds are possible in terrain-favored areas.
Single digit RH is possible in parts of central/northern Nevada, but
15-20% will be more common elsewhere.
Critical conditions are expected along the Sierra Front in northwest
Nevada. Here, the mid-level jet will enhance winds aloft during the
afternoon. While the surface low will not be overly deep, the
combination of these factors will support winds around 20 mph near
the terrain. Gusts to around 30 mph are also possible. There is some
potential for high level clouds to limit RH reductions. Even with
some of these marginal factors, wind speeds should be sufficient to
promote rapid fire spread in fuels that are very dry (ERCs above
90th percentile).
..Wendt.. 07/20/2025
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 192116
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0416 PM CDT Sat Jul 19 2025
Valid 211200Z - 271200Z
A positive-tilt mid/upper-level trough, with enhanced mid-level flow
along it's base, is forecast to remain across the Pacific Northwest
Day 3/Monday. Thereafter, the trough is forecast to eject across the
northern Rockies and into Canada through midweek. Meanwhile, a
portion of the trough is forecast to become cutoff off the
California coast Day 5/Wednesday through perhaps Day 7/Friday before
ejecting northeastward, with a large-scale trough returning across
the Western United States next weekend.
...Day 3/Monday - Day 4/Tuesday: Wind/RH...
Mid-level winds are forecast to increase over the northern Great
Basin Day 3/Monday as the aforementioned trough impinges on the
area. A rather broad area of elevated fire weather conditions are
likely, with critical fire weather conditions most likely across
portions of the Snake River Plain in Idaho, along the Nevada,
Oregon, and Idaho border, and across western/northwestern Nevada and
adjacent portions of California where wind speeds are forecast to be
strongest. Though, at this time, critical fire weather conditions
appear too brief/spotty to introduce greater probabilities.
Dry and breezy conditions are forecast to continue Day 4/Tuesday
across much of the Great Basin. Though, relaxing mid-level winds and
reduced surface pressure gradients should limit widespread fire
weather concerns.
...Day 3/Monday - Day 4/Tuesday and Day 6/Thursday - Day 8/Saturday
: Dry Thunderstorms...
Dry thunderstorms are possible Day 3/Monday into Day 4/Tuesday
across portions of the northern Great Basin, Northwest, and northern
Rockies, as increasing moisture associated with the aforementioned
trough overspreads the area. While forecast guidance suggests
precipitable water values may be relatively high (0.8 - 1+ inch),
somewhat fast-moving storm motions and critically receptive fuels
suggest a mix of wet/dry modes. At this time, uncertainty remains
too large to introduce probabilities for dry thunderstorms.
Dry thunderstorm potential may return across the western United
States by Day 6/Thursday as the aforementioned cutoff low begins to
move onshore. Though, at this time, forecast guidance differs on the
timing/evolution of the low, which reduces confidence in timing and
coverage of dry thunderstorms.
..Elliott.. 07/19/2025
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