A very unstable environment with dry conditions at the surface will create weather weather conditions that could promote rapid fire spread. Around a 25% chance of thunderstorms in the area which could produce lightning and gusty outflow winds as high as 40 mph. * AFFECTED AREA. In Oregon, Fire Weather Zone 689 Northern Willamette National Forest and Fire Weather Zone 690 Southern Willamette National Forest. * THUNDERSTORMS. Isolated to scattered thunderstorms. Around a 25% chance of thunderstorms. 10-20% chance of wetting rains in passing storms. * DRY AND UNSTABLE. Unstable conditions with elevated mixing heights may promote pyroconvective activity. * OUTFLOW WINDS. Instantaneous gusts as high as 40 mph. Gusts at these speeds can be observed tens of miles away from the core of the thunderstorm. * IMPACTS. Conditions may be favorable for rapid fire spread which may threaten life and property. Thunderstorm outflow winds may result in unanticipated erratic fire spread. High instability may result in fire growth. Frequent lightning and critically dry fuels may result in fire starts.