...ISOLATED TO SCATTERED THUNDERSTORMS WILL LEAD TO CRITICAL FIRE WEATHER CONDITIONS THROUGH THURSDAY MORNING... .An upper weather system moving across the region this afternoon through Thursday morning will lead to the development of thunderstorms starting in Central Oregon, with activity moving north into the central WA Cascades tonight. Thunderstorms will be capable of frequent lightning, heavy downpours, and gusty outflow winds. 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. * AFFECTED AREA...Fire Weather Zones 700 Central Mountains of Oregon, 703 Warm Springs Reservation, 704 Northern Deschutes National Forest and 705 Southern Deschutes National Forest. * TIMING...Until 11 PM PDT this evening. * IMPACTS...Any fire that develops will catch and spread quickly. Outdoor burning is not recommended. * THUNDERSTORMS...Rain amounts will range from 0.05 to 0.15 inches, with stronger storms capable of producing 0.25 inches or more. * OUTFLOW WINDS...25 to 45 mph, locally higher.