U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 261604
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1104 AM CDT Thu May 26 2022
Valid 261700Z - 271200Z
Only minor modifications were made to the ongoing forecast based on
current guidance. Widely scattered virga showers with gusty outflow
winds are possible in central/northern Nevada. Thermodynamic
profiles remain marginally supportive of a few lightning flashes
across the region. With most area fuels still only marginally dry,
particularly the larger fuels, ignition efficiency from any
lightning activity is expected to be low.
..Wendt.. 05/26/2022
.PREV DISCUSSION... /ISSUED 0107 AM CDT Thu May 26 2022/
...Synopsis...
Elevated fire weather concerns remain likely this afternoon across
northwestern to southern Nevada. Early-morning water vapor imagery
reveals an upper-level wave approaching the Pacific Northwest.
Surface pressure falls across the northern Great Basin will induce
south to southwesterly winds off the Sierra Nevada and lower CO
River Valley. Sustained winds between 15 to 20 mph are expected by
early afternoon based on ensemble guidance. However, deep
boundary-layer mixing will support frequent wind gusts between 25-35
mph, especially across central to southern NV where nearly all
solutions show the strongest low-level mass response. Downslope
effects, combined with antecedent dry conditions and diurnal
warming, will support RH reductions into the 10-15% range across
much of the region. Consequently, elevated (to briefly critical)
fire weather conditions appear likely, including across far western
NV where several lightning strikes were noted Wednesday afternoon.
...Dry Thunderstorms...
The approaching upper low will also support the potential for
isolated to scattered thunderstorms by late afternoon across the
Pacific Northwest and parts of the northern Great Basin. Observed 00
UTC soundings show an increase in column precipitable water over the
region, but values remain near 0.3 to 0.5 inches. Continued
moistening is expected, but PWATs will likely remain near 0.5 to
0.75 across NV and will support a dry-lightning threat. While the
probability for thunderstorms is highest across portions of OR, WA,
and ID, a few dry thunderstorms are possible across central to
northern NV. An isolated dry-thunderstorm risk area is introduced
where confidence in thunderstorms overlapping with critically dry
fuels is highest.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 260649
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0149 AM CDT Thu May 26 2022
Valid 271200Z - 281200Z
...Synopsis...
Increasing west to southwest winds across parts of the southern
Great Basin, Southwest, and Four Corners will lead to a broad swath
of fire weather concerns Friday afternoon. The upper-level wave
currently approaching the Pacific Northwest is forecast to translate
into the northern Rockies by late Friday. Falling heights aloft will
support modest surface pressure falls over the inter-mountain West,
resulting in a broad low-level mass response from the southern Great
Basin into the Four Corners and Southwest. Ensemble guidance and
deterministic solutions generally suggest that 15-20 mph winds will
be common across this region. Drier/windier solutions indicate that
areas of 20-25 mph winds are possible, but considerable spread in
deterministic solutions introduces uncertainty regarding the exact
placement and coverage of the strongest winds. Strong mid and
upper-level winds will largely be displaced to the north of the
region, which further limits confidence on where the windiest
corridors will be established within the risk area.
Nonetheless, dry conditions will prevail with 10-15% RH values
expected by late afternoon. Widespread elevated conditions are
likely, and a few corridors of critical conditions are possible.
Similar wind/RH conditions are possible across much of the southern
High Plains as well, but widespread rainfall over the past few days
has mitigated fuel status for the time being. Fuel trends will be
monitored for a possible expansion, but Friday's warm/dry conditions
will likely begin the drying process for most locations as
temperatures rebound into the 90s.
..Moore.. 05/26/2022
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 252030
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0330 PM CDT Wed May 25 2022
Valid 271200Z - 021200Z
Upper-level ridging in the West will continue to shift eastward late
this week into the weekend. The next West Coast trough will move
ashore Saturday/Sunday. This large-scale trough will remain over the
Great Basin until some time mid/late next week. This pattern will
favor High Plains lee troughing/cyclogenesis each day until the
upper trough lifts northeast and loses amplitude. Fire weather
concerns will remain focused from the Great Basin into the Southwest
and possibly the central/southern High Plains.
...Great Basin...
As mid-level flow increases across the region on Friday, potential
for critical fire weather will increase as a surface trough deepens
in the central Basin. Given the late arrival of the stronger
mid-level winds and weak surface response, potential for critical
fire weather remains at 40%. Stronger winds are possible into the
eastern Basin by Saturday. At present, fuels may only be marginally
dry and higher critical probabilities will be withheld.
...Southwest...
Fire weather concerns will increase across the region beginning
Friday. A broad area of potentially critical fire weather is
forecast for much of Arizona/New Mexico. The stronger mid-level
winds will be displaced to the northwest and only weak lee troughing
will exist to the east. Some stronger winds may occur north of the
Mogollon Rim, but sparse fuels will limit the threat.
Greater potential for critical fire weather will exist on Saturday
into Monday. Mid-level winds will continue to increase each day with
deepening surface cyclones expected in the central High Plains.
Strong surface winds are expected across the region along with
continued dry conditions. Some mid/high-level clouds are possible,
but this is not expected to limit concerns for most areas.
...Central/Southern High Plains...
Given recent precipitation, it is not entirely clear how much of a
fire weather risk will develop over the weekend into early next
week. Fuel conditions will continue to be monitored over the next
few days as meteorological conditions would support higher
probabilities during parts of the Friday through next Monday time
frame.
...Sacramento Valley...
The upper-level pattern within guidance would continue to support
some increase in fire weather concerns on Monday. As before, the
level of risk will depend on precipitation that occurs with the
trough moving in during this coming weekend. Uncertainty is too high
for highlights at this time.
..Wendt.. 05/25/2022
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