ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 250732
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0132 AM CST Wed Nov 25 2020
Valid 251200Z - 261200Z
A mid-level trough will deepen across the Inter-mountain West as a
trough aloft de-amplifies across the eastern CONUS. The eastward
advance of the western upper trough will induce surface
lee-troughing across the southern High Plains during the day and
building surface High Pressure across the Pacific Northwest and
western Great Basin by the end of the period. Dry and breezy
conditions are expected to accompany the lee-troughing across the
southern High Plains, with a surface pressure gradient becoming
established across California, marking the beginning of a multi-day
offshore flow event conducive to wildfire spread.
...Southern High Plains...
The latest model guidance consensus depicts 15-20 mph sustained
westerly surface winds and 15-25% RH by afternoon peak heating along
the lee of the southern Rockies towards the Trans Pecos range.
However, these conditions are expected to be relatively localized in
most places given upper ridging and associated lack of upper
support. Guidance consensus does depict a larger region of Elevated
conditions across east-central New Mexico, where confidence is high
enough to maintain an Elevated highlight.
...Portions of southern California...
After 06Z Thursday, the aforementioned pressure gradient is expected
to intensify across portions of southern California, encouraging at
least widespread 15-25 mph sustained offshore flow. However, these
stronger winds are expected to arrive in advance of the drier
airmass, with surface RH values in the 25-35% range expected before
12Z (end of the period). Given the delay of the arrival of drier
air, an Elevated area has been withheld this outlook. Shortly after
12Z, drier air and even stronger winds are expected to promote
considerable wildfire spread potential. Please see the latest Day 2
Fire Weather Outlook for more information regarding Thursday's