Fire Weather Outlook Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14
FNUS21 KWNS 251544

Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1043 AM CDT Mon Sep 25 2017

Valid 251700Z - 261200Z

Previous outlook remains on track and no changes are necessary. See
discussion below for more details.

..Leitman.. 09/25/2017

.PREV DISCUSSION... /ISSUED 0155 AM CDT Mon Sep 25 2017/

The persistent upper trough/low centered over the Great Basin will
begin to lift northeastward into the northern Plains and adjacent
Canadian provinces throughout the period. Northerly mid-level winds
of 35 to 45 kt are forecast over much of CA along the western
periphery of the upper trough. At the surface, high pressure will
remain anchored over the Great Basin and northern/central Rockies
through the period, which will support a weak to locally moderate
offshore wind event across portions of southern CA.

...Portions of the Sacramento Valley and Adjacent Coastal Ranges of
Northern CA...
Enhanced mid-level winds, combined with diurnal heating, should
allow for modest northerly surface winds to mix to the surface this
afternoon across portions of the Sacramento Valley and adjacent
Coastal Ranges of northern CA. Sustained winds up to 15 mph appear
possible, with stronger gusts occurring at higher elevations. RH
values will once again decrease into the 10-20% range given an
antecedent dry low-level airmass and diurnal heating. These forecast
meteorological conditions combined with continued dry fuels support
an elevated designation across this region.

...Portions of Southern CA...
Elevated fire weather conditions are ongoing early this morning and
will develop again Tuesday morning across portions of southern CA
when the surface pressure gradient will be maximized. During these
periods, offshore winds will increase to 15-20 mph, with stronger
gusts possible in higher elevations. RH values will likely remain
low through much of the period owing to downslope warming/drying
effects, and overnight RH recovery is forecast to remain poor. 06Z
surface observations support these forecast trends, particularly at
high elevations where winds are gusting to 25-30 mph and RH lowering
to near 20% in a few locations. The continuation of drying fuels
across this region supports the elevated area. The lack of an even
stronger forecast surface pressure gradient and related winds
continues to preclude a critical designation.

...Please see for graphic product...

$$ is the U.S. government's official web portal to all federal, state and local government web resources and services.