868
FNUS28 KWNS 032022
FWDD38

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0320 PM CDT Wed Jul 03 2024

Valid 051200Z - 111200Z

The beginning of the forecast period on D3/Friday is characterized
by overall amplification of ridging across the Pacific Northwest. An
upper-level shortwave trough is forecast to move southeast out of
British Columbia into the Northwest US by D4/Saturday, moving into
the Northern Great Basin by D5/Sunday. Guidance begins to diverge
significantly heading into D6/Monday, but the overall consensus is
that upper-level ridging will continue to build over the Western US.
Conditions will be hot and dry beneath the ridge for a prolonged
period, contributing to the continued curing of fuels. Medium-range
guidance hints at the possibility of an upper-level shortwave trough
approaching the Northern California coast on D5/D6, which could
increase the potential for dry thunderstorm occurrence. However,
there is significant disagreement in the timing, placement, and
orientation of this upper-level feature.

...Pacific Northwest into the Northern Great Basin...
As an upper-level trough descends from British Columbia into the
Pacific Northwest on D4/Saturday, conditions beneath the jet streak
are expected to be hot, dry, and windy over the Snake River Valley
into portions of the Northern Great Basin. Elevated to near-critical
conditions will be possible. However, the GFS and ECMWF forecasts
differ in the intensity and orientation of the jet streak, resulting
significant differences in the forecast surface winds between the
two. Given the prolonged heat beneath the ridge, however, current
thinking is to weight towards the drier, windier solution of the
GFS.

...West Coast...
Starting D5/Sunday into D6/Monday, GFS and ECMWF forecasts both hint
at an upper-level shortwave trough interacting with the northern
periphery of the ridge, though solutions differ greatly in the
placement, orientation, and intensity of both the trough and ridge.
While areas of Northern California into the Pacific Northwest will
need monitoring for potential dry thunderstorm occurrence later in
the period, forecast uncertainty is too great to introduce
probabilities at this time.

..Halbert/Lyons.. 07/03/2024

...Please see www.spc.noaa.gov/fire for graphic product...

$$