536
FNUS28 KWNS 292130
FWDD38

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0428 PM CDT Sat Jun 29 2024

Valid 011200Z - 071200Z

While initially limited in scope, fire-weather concerns appear
likely to increase through the extended forecast period as a strong
ridge of high pressure builds over the West Coast. Very hot
temperatures and dry surface conditions should gradually increase
fire danger over much of the West, as stronger northwest flow over
the Great Basin will continue through mid to late week. Ridge
breakdown is expected late in the forecast period as early as next
weekend. Uncertainty on the character of the pattern following this
transition remains high, but dry and breezy conditions are possible
through much of next week and into next weekend across the interior
Northwest and Great Basin

...Interior Pac. Northwest & northern Great Basin...
As the ridge builds quickly this weekend, enhanced flow aloft will
develop along the eastern periphery as a weak trough moves south out
of Canada. At the surface, a weak cold front should move south into
the Great Basin, enhancing surface winds and the chance for isolated
thunderstorms over parts of OR, NV, UT, and ID. Isolated critical
fire-weather conditions could occur D3/Mon as the gusty winds and
low RH spread through the northern Great Basin and Snake River
Valley.

Behind the front, dry northwesterly surface flow should continue
through the first part of the week as the ridge aloft intensifies.
Very warm temperatures should allow for an increase in fire danger
indices through the week before another shortwave trough and cold
front pass along the eastern portion of the ridge D5/Wed and
D6/Thur. Gusty surface winds are likely over portions of the
northern Great Basin and southern ID along, with very dry surface
conditions. With increasingly dry fuels, critical fire-weather
conditions may develop.

At the end of the forecast period, most medium-range guidance shows
the upper-ridge breaking down ahead of a trough moving into the
Pacific Northwest. It remains unclear exactly how this transition
will evolve, with some guidance showing an increase in showers and
thunderstorms, while others show a more substantial increase in hot,
dry and windy conditions with trough passage. Regardless of the
outcome, an increase in fire-weather potential is very likely, owing
to the antecedent hot and dry conditions beneath the weakening
ridge.

...Northern CA...
Under the ridge aloft, a thermal trough is likely to extend from the
Desert Southwest through northern CA, leading to poor RH recovery
and occasional gusty winds from early to mid week next week. Gusty
northerly winds are possible in portions of northern CA, especially
in/around the Sacramento Valley. Drying fuels and the increase in
temperatures are likely to support at least some isolated
fire-weather risk through the next several days, though the exact
coverage and duration are currently unclear.

..Lyons.. 06/29/2024

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

$$