Fire Weather

SPC Day 2 Fire Weather Outlook

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook Image
Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0216 PM CDT Sat Jul 21 2018

Valid 221200Z - 231200Z

Relatively small northward and southward expansions have been made
to the isolated dry thunderstorm area across parts of northern CA,
southern OR, and far northwestern NV. Mid-level moisture is forecast
to increase by Sunday afternoon on the western periphery of an upper
ridge, and at least isolated convection should initiate across the
higher terrain of this region. Flow through the cloud-bearing layer
is not expected to be overly strong, and this may tend to limit
storm motions. Regardless, very dry/receptive fuels will likely
support new fire starts with any lightning strikes. Confidence is
not high enough in greater thunderstorm coverage to include a
scattered dry thunderstorm area at this time.

No changes have been made to the isolated dry thunderstorm area
across northeastern NV into northern UT and western WY. Precipitable
water values should be close to 1.00 inch over much of this region,
and wetting rainfall may occur with some thunderstorms. Latest
short-term guidance continues to suggest that there will be a
relative minimum in thunderstorm activity across north-central NV
Sunday afternoon/evening. Have therefore not combined the two
isolated dry thunderstorm areas.

The elevated area across parts of the Snake River Valley of ID
remains warranted, and only minor expansions have been made. The
lack of even stronger forecast low-level winds continues to preclude
a critical area.

..Gleason.. 07/21/2018

.PREV DISCUSSION... /ISSUED 0203 AM CDT Sat Jul 21 2018/

A shortwave trough will move through Montana on Sunday and will
de-amplify throughout the day. This will lead to weakening mid-level
flow across much of the Pacific Northwest. Enough flow may remain
for some near-critical wind speeds in eastern portions of the Snake
River Valley during peak afternoon mixing, but currently it appears
sustained winds will remain less than 20 mph. Some isolated dry
thunderstorms will be possible on the periphery of the monsoon along
the northern portion of the Great Basin and also across northern
California into southern Oregon and northwest Nevada. Rainfall in
these areas has been limited over the past week or two and PWAT
values around 0.8 inches indicate that any storms which form will
likely be on the drier side.

...Please see for graphic product...

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