U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 080652
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0152 AM CDT Tue Jul 08 2025
Valid 081200Z - 091200Z
...Synopsis...
Along the northwestern periphery of an expansive midlevel ridge over
the Southwest, a midlevel low will approach the northern CA coast as
it gradually phases with a robust midlevel trough moving across
British Columbia. Large-scale ascent preceding the midlevel low will
promote isolated dry/high-based thunderstorms over the higher
terrain of OR into far southeastern WA. Given dry/receptive fuels
and limited rainfall with these storms, lightning-induced ignitions
will be possible, along with strong convective outflow.
Additionally, strong deep-layer westerly flow in the base of the
midlevel trough moving across British Columbia will overspread the
Cascades, resulting in dry/breezy downslope flow and elevated
fire-weather conditions in the Columbia Basin.
Farther south, a belt of enhanced midlevel southwesterly flow will
overspread the Great Basin between the large-scale ridge and
midlevel low. Deep boundary-layer mixing into this enhanced flow
aloft will favor dry/breezy conditions over central NV into western
UT, and given dry fuels, elevated fire-weather conditions are
expected.
..Weinman.. 07/08/2025
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 080653
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0153 AM CDT Tue Jul 08 2025
Valid 091200Z - 101200Z
...Synopsis...
A compact midlevel trough will track eastward across the Northwest
during the day -- in tandem with a robust midlevel trough/low moving
eastward from British Columbia into Alberta. Large-scale ascent
preceding the midlevel trough moving across the Northwest will
promote another day of isolated high-based thunderstorms -- with a
focus over southeastern OR into southwestern ID. Deep inverted-V
soundings and PW around 0.7 inches will favor dry thunderstorms
capable of producing lightning-induced ignitions and strong/erratic
outflow winds.
Similar to Day 1/Tuesday, a belt of strong deep-layer westerly flow
(peripheral to the midlevel trough) across the Cascades will lead to
breezy/gusty westerly surface winds in the Columbia Basin. While
increasing boundary-layer moisture will limit RH reductions compared
to Day 1/Tuesday, stronger surface winds will offset this and still
yield elevated fire-weather conditions.
Over the Great Basin, moderate midlevel southwesterly winds
accompanying the compact midlevel trough will overspread the Great
Basin during the day. Deep boundary-layer mixing into this
strengthening flow aloft will support another day of elevated to
locally critical fire-weather conditions, given increasingly
dry/receptive fuels.
..Weinman.. 07/08/2025
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 072200
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0500 PM CDT Mon Jul 07 2025
Valid 091200Z - 151200Z
...Day 3/Wednesday...
Stronger west winds with the arrival of a mid-level short wave
trough and attendant cold front are expected across the Columbia
Basin where fuels remain dry. Although cooler temperatures and
slightly higher humidity arrive with the cold front, sustained west
winds of 15-25 mph will continue to support a fire weather threat
amid dry fuels across the Columbia Basin. A mid-level short wave
trough will translate over a broad ridge situated over the
Southwestern U.S. Collocation of ascent ahead of a mid-level jet max
and antecedent mid-level moisture should support isolated
thunderstorms with limited rainfall across southeastern
OR/southwestern ID on Day 3/Wednesday. The accelerated mid-level
flow on the southern periphery of the aforementioned short wave
along with a deep/well-mixed boundary layer will promote elevated
west-southwest winds across much of the Great Basin and portions of
southern Idaho. The breezy and very dry conditions support at least
a 40% probability for critical fire weather conditions across the
region amid an expected dry fuelscape.
...Day 4/Thursday...
The mid-level short wave edges eastward into the Southern Rockies
bringing elevated west winds to the Intermountain West and great
Four Corners region Day 4/Thursday. A 40% probability for critical
fire weather was introduced into southern UT and northern AZ where
fuels will go under several days of drying through midweek, becoming
more receptive to wildfire spread.
...Day 5-8/Friday-Monday...
Building heat is expected across much of the Western U.S. through
the weekend under an expanding mid-level ridge over southern CA
which will promote a limited wind threat across the region. Monsoon
moisture and associated thunderstorms will remain confined to
southern AZ and NM through the weekend.
..Williams.. 07/07/2025
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