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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 141648
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1148 AM CDT Mon Jul 14 2025
Valid 141700Z - 151200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL WASHINGTON...
...Central/Northeastern Utah and Northwestern Colorado...
A weak upper-level wave evident in water vapor imagery will move
through northern Utah today. Slightly increased mid-level flow on
the southern periphery of the wave will support enhanced dry
downslope flow into the Uinta Basin and along and east of the
central Utah mountain chain. Sustained winds of 10-15 mph along with
10-15 percent relative humidity will result in a period of elevated
fire weather conditions over dry fuels where ERC values are around
the 97th percentile.
Otherwise, no major changes to previous forecast (see below) for the
Northwest, Great Basin or Snake River Plain highlights.
..Williams.. 07/14/2025
.PREV DISCUSSION... /ISSUED 0138 AM CDT Mon Jul 14 2025/
...Synopsis...
A mid-level trough will bring a belt of enhanced westerly flow aloft
across portions of the Pacific Northwest today. A period of Elevated
to Critical fire weather conditions can be expected across the
Columbia River Basin in Oregon and Washington and in the Snake River
Plain in Idaho. The trough will also promote dry thunderstorm
development across the Great Basin.
...Cascades and Columbia River Basin...
Relative humidity reductions to 15-20 percent will combine with west
winds around 15 mph promoting elevated fire weather concerns for the
Columbia River Basin through Monday afternoon. A considerable wind
shift is expected with the dry cold front passage beginning early
afternoon across the Okanagan Valley before reaching the Columbia
River by evening. Although relative humidity will rise behind the
front, a few hours of sustained north winds of 20-30 mph will create
Critical fire weather concerns and could significantly impact
existing active or new fires Monday.
...Snake River Plain...
Relative humidity reductions to 15-20 percent will combine with
westerly winds around 10-15 mph (locally higher) through Monday
afternoon. Locally stronger winds may bring near Critical to
Critical conditions, however the localized nature precludes
inclusion of a Critical area at this time.
...Dry Thunderstorms...
Forcing for ascent with the upper-level trough will allow for high
based convection to develop across portions of the northern Great
Basin. Primarily mid-level moisture will overspread a very dry and
warm boundary layer, with little to no precipitation and storm
motions around 10-20 mph. This in combination with critical fuels
supports maintaining and area of isolated dry thunderstorm chances
across northern Nevada into southeastern Oregon, southern Idaho, and
far northeastern Nevada.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 141956
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Mon Jul 14 2025
Valid 151200Z - 161200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEVADA INTO
WESTERN UTAH AND NORTHERN ARIZONA...
...Dry Thunderstorms...
An expansive area of isolated dry thunderstorms across the was
maintained for this update, with only slight northward adjustments
to highlights into north central Nevada as well as southeastern ID
and far western WY given latest model guidance consensus. An
advancing mid-level trough into the northwest and attendant
increased mid-level flow will support faster thunderstorm motions
particularly across central and northeastern NV Tuesday, with
northeast trajectories of 20-30 mph. This will limit rainfall
residence time and increase lightning ignition efficiency over dry
fuels.
...Great Basin...
Enhanced westerly flow over western Nevada associated with the an
encroaching mid-level trough over a deeply mixed boundary layer will
promote west winds approaching 20 mph across northwestern NV.
Relative humidity combined with higher winds will support an
elevated fire weather threat amid dry fuels. Higher winds under a
similarly dry boundary layer will bring critical fire weather
conditions to portions of eastern NV, southwestern UT and the
Arizona Strip.
..Williams.. 07/14/2025
.PREV DISCUSSION... /ISSUED 0144 AM CDT Mon Jul 14 2025/
...Synopsis...
A deepening mid-level wave will bring an increase in winds and
potential for dry thunderstorms across the Great Basin on Tuesday.
Elevated to Critical conditions can be expected in portions of
eastern Nevada, western Utah, northern Arizona and southern Idaho.
...Eastern Nevada, western Utah, northern Arizona...
Increasing southwesterly flow around 10-20 mph will overlap with
afternoon relative humidity reductions to around 10-15 percent on
Tuesday afternoon. The best overlap of Critical winds and relative
humidity appears to be across eastern Nevada into western Utah.
Further south into northern Arizona and the Arizona Strip, winds may
be at or just below Critical thresholds. However, ongoing fires with
a history of erratic fire behavior warrant inclusion into the
Critical area. Gusty and erratic winds from nearby thunderstorms
will also be possible.
...Dry Thunderstorms...
Isolated dry thunderstorms will be possible on the periphery of
deeper monsoonal moisture across portions of northern Arizona into
western Colorado, Utah, far southern Idaho, western Wyoming, and
Nevada. Within these regions, PWs generally around 0.25-0.50" are
expected with moisture remaining primarily mid-level with drier
boundary layer conditions below. This will promote high based
convection with little precipitation amid faster storm motions with
the mid-level trough passage. Fuels within these regions are
receptive to ignition and as such an isolated dry thunder area was
maintained with this outlook.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 142155
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0455 PM CDT Mon Jul 14 2025
Valid 161200Z - 221200Z
...Day 3/Wednesday...
Elevated mid-level flow south of a mid-level trough translating
eastward into the Northern Plains will contribute to breezy winds
across the southern Great Basin Day 3/Wednesday. Monsoon moisture in
place across the eastern Great Basin and Upper Colorado River Basin
and daytime destabilization over higher terrain will support
isolated afternoon thunderstorms across the this region. A dry sub
cloud layer will inhibit significant rainfall, increasing lightning
ignition efficiency over very dry fuels. Deeper monsoon moisture
across southern Arizona and New Mexico will inhibit new ignitions
under heavier rain cores.
...Day 4/Thursday...
Monsoon moisture surge makes northward progress into the Desert
Southwest aided by mid-level low over Baja California. Increasingly
deeper moisture will push the dry thunderstorm threat north of the
Four Corners region Day 4/Thursday, with the eastern Great Basin,
Utah and the Western Slope holding on to a dry boundary layer
prohibiting appreciable rainfall.
...Day 5-8/Friday-Monday...
The monsoon moisture surge, including widespread precipitable water
values of 0.75-1.00 inches, is expected to push into the
Intermountain West Day 5/Friday. Generally slow thunderstorm motions
and higher precipitation efficiency should limit new ignition
potential in this environment. Another mid-level trough and
associated strengthening mid-level flow entering the Pacific
Northwest will bring breezy and dry conditions back into central
WA/OR as well as northeastern CA and northwestern NV where
increasingly dry and receptive fuels exist. Drier conditions return
to much of the West with associated convection shunted towards the
Continental Divide over the weekend by a broad westerly flow.
..Williams.. 07/14/2025
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