Storm Prediction Center Day 1 Fire Weather Outlook
Created: Tue Jul 17 15:31:03 UTC 2018 (
| 
)
Storm Prediction Center Day 1 Fire Weather Outlook
Created: Tue Jul 17 15:31:03 UTC 2018 (
| )
| |||||||||
Click for Day 1 FireWX Areal Outline Product
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 171529
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1029 AM CDT Tue Jul 17 2018
Valid 171700Z - 181200Z
Forecast looks on track and only minor changes were made. Please see
the forecast discussion below for more details.
..Nauslar.. 07/17/2018
.PREV DISCUSSION... /ISSUED 0209 AM CDT Tue Jul 17 2018/
...Synopsis...
A weak 500 mb shortwave trough will pass over the northern Great
Basin during the afternoon. Mid-level moisture will also move
eastward in association with the shortwave trough. At the surface, a
thermal trough will develop east of the Cascades down into far
northern Nevada.
...Central Washington/Oregon...
A thermal low will become established along the lee of the Cascades
during peak heating of the afternoon, as temperatures are expected
to reach up to 100F in some locales. The thermal low induced
pressure gradient will generate downslope sustained surface winds of
at least 15-20 mph in tandem with 10-20% RH. Fuels are receptive in
this area, with elevated RH/wind criteria being met for fire spread
potential. Stronger surface winds (20-25 mph) may occur along the
immediate eastward facing slopes of the Cascades along with
critically low RH. The brevity of the critical conditions warrant
only an elevated delineation at this time.
...Southern Idaho...
Strong surface heating during the mid-late afternoon may induce a
weak pressure gradient in the Snake River Plain. Sustained surface
winds of 15-20 mph are expected along with critical RH. An elevated
delineation was added given the receptive nature of fuels in this
area.
...Southwest Wyoming...
A weak thermal low and associated pressure gradient may develop in
the Green River Basin. 15-20 mph sustained surface winds are
expected along with 15-20% RH. Though the RH is marginally low and
recent rainfall from scattered storms has recently occurred, 10-hr
fuels remain receptive to the spread of grass fires. An elevated
delineation was added to account for the stronger surface winds
overlapping rebounding finer fuels.
...Idaho/Montana border into far western Wyoming...
As the aforementioned mid-level shortwave trough progresses
eastward, deep-layer ascent and at least marginal buoyancy will
foster the development of isolated thunderstorms across the area.
Precipitable water values of 0.5-0.75 inches and a relatively deep
sub-cloud layer suggests that dry lightning will be possible. Modest
mid-level flow will also allow faster storm motions (above 20
knots), reducing accumulating rainfall atop fuels receptive for fire
weather spreads.
...Please see www.spc.noaa.gov/fire for graphic product...