Red Flag Warning issued September 7 at 1:32PM PDT until September 7 at 11:00PM PDT by NWS Pendleton OR
…UNSTABLE CONDITIONS CONTINUE, WITH THUNDERSTORMS DEVELOPING
ONCE AGAIN TONIGHT AND SUNDAY…
.Unstable conditions will persist once again today, before an
oncoming weather system shifts the threat from instability to that
of thunderstorms. Clearing has been observed across central
Oregon, and with that, scattered thunderstorms are expected to
develop this evening. Storms are expected to develop over the
eastern mountains tomorrow afternoon as well, however forecast
confidence remains on the lower end, so will hold off on upgrading
the watch there for now.
The National Weather Service in Pendleton has issued a Red Flag
Warning for abundant lightning, which is in effect until 11 PM
PDT this evening. The previous Red Flag Warning for dry and
unstable conditions is no longer in effect.
* AFFECTED AREA…Fire Weather Zone 640 Central Mountains of
Oregon.
* TIMING…Now through Saturday evening.
* RELATIVE HUMIDITY…As low as 12 percent.
* TEMPERATURES…Up to 90.
* IMPACTS…New fire starts, as well as rapid fire spread due to
outflow winds.
* ADDITIONAL INFORMATION…Light shower activity and cloud cover
this morning has brought the Haines Index in the area below
critical thresholds. Dry thunderstorms are now the primary
critical fire weather threat for the zone.
* THUNDERSTORMS…Scattered thunderstorms producing abundant
lightning and gusty outflow winds. Storms are expected to be dry
in nature.
* OUTFLOW WINDS…Storms may be capable of producing outflow winds
up to and over 40 mph.
A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.