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FNUS28 KWNS 232009

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0308 PM CDT Sat Sep 23 2017

Valid 251200Z - 011200Z

An upper trough will be centered over the western U.S. at the
beginning of the period. The northern branch of this trough will
progress eastward  across the Great Lakes by mid-week as a cut-off
low develops over parts of the southwestern deserts and lower
Colorado Valley. At the surface, high pressure will encompass much
of the Pacific Northwest and Great Basin toward the northern and
central Rockies for much of the period. This pattern will result in
favorable conditions for several days of light to moderate offshore
winds across portions of CA.

...Day 3-5/Mon-Wed -- Portions of CA...

Deep-layer north/northeasterly flow will be positioned over CA at
the beginning of the period and persist through at least Day 5/Wed.
Flow will generally be weak below 700 mb, but some strengthening is
possible on Tuesday when the southern branch of the upper trough
begins to cut-off and a weak impulse traverses through the back side
of the western trough. Medium range guidance continues to show a
modest surface pressure gradient across the region, teetering on
critical margins on Tuesday. At this time, surface wind speeds are
expected to mainly be in the 10-20 mph with gusts as high as 40 mph
in wind-prone areas. Furthermore, high temperatures will warm into
the 80s to near 90 degrees and afternoon RH values falling into the
10-15 percent range with poor overnight recovery. This will result
in several days of elevated fire weather potential with perhaps some
brief/spotty critical conditions possible, especially on Tuesday.

..Leitman.. 09/23/2017

...Please see for graphic product...

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