651
FNUS21 KWNS 231618
FWDDY1

Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1117 AM CDT Sun Jun 23 2024

Valid 231700Z - 241200Z

The previous forecast generally remains on track with only minor
adjustments made to reflect recent fire reports, morning surface
observations, and trends in latest high-res guidance. A dry frontal
passage is underway across the Pacific Northwest as mid-level winds
increase over the central Cascades (based on the evolution of
high-level cirrus over the region). Surface pressure falls in the
lee of the Cascades/northern Sierra Nevada should become more
apparent in the coming hours with an attendant increase in surface
winds. Latest guidance suggests the onset of elevated fire weather
conditions will be around 18 UTC along/east of the Sierra Nevada and
Cascades with a slightly later onset for the Snake River Plain.
Localized critical conditions also remain possible through the
Columbia Gorge and along the NV/OR border; however, higher RH with
northward extent and displacement from the stronger mid-level flow
with southern extent continue to limit confidence in the
coverage/duration of critical conditions.

..Moore.. 06/23/2024

.PREV DISCUSSION... /ISSUED 0124 AM CDT Sun Jun 23 2024/

...Synopsis...
An upper-level trough will move through parts of the Northwest
today, favorably timed with peak heating. Surface low pressure will
deepen in the lee of the northern and Canadian Rockies. Surface
winds will increase across the region and into the northern Great
Basin.

...Columbia Basin...
Winds of 15-20 mph (higher downwind of the Cascade Gaps) are
expected by the afternoon. RH may only lower to around 20% in many
places due to at least some push of marine air across the Cascades.
Given the relatively dry fuels and the expected winds, elevated fire
weather is possible.

...OR/NV/CA...
Temperatures will be warmer and RH lower farther south. RH could
fall to near 10-15% over a broad area. Winds away from the mid-level
jet will be slightly weaker, but 15-20 mph is still possible,
especially near terrain features. With dry fuels in these areas,
fire weather concerns will be elevated.

...Snake River Plain...
The southern periphery of the mid-level jet will sag into southern
Idaho. This, combined with the strengthening surface pressure
gradient, will promote 15-25 mph winds within the valley. RH of
15-20% appears probable. Duration of potentially critical conditions
will be minimal and fuels are not yet critically dry. That said,
elevated to locally critical fire weather is expected during the
afternoon.

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

$$