A moist and unstable environment coupled with weak forcing along a passing upper-level front led to scattered strong thunderstorms along the East Slopes of the Washington Cascades during the early afternoon hours of June 29th.  Although storm motion was on the order of 20 to 30 miles per hour, cell training across the higher terrain of southeastern Chelan County led to rainfall amounts ranging from one to one and a half inches over the duration of an hour.  The runoff from these storms flowed down Canyons One and Canyon Two into the city of Wenatchee and sewer systems became overwhelmed resulting in flash flooding across southwestern portions of the city.  These storms also fell over portions of the 2012 Peavine burn scar resulting in two known debris flows; one that carried debris from Tronsen Ridge and washed out a section of Upper Tronsen Road and a second that deposited hundreds of trees onto USFS Trails in Devil's Gulch.  Further east closer to the Idaho border, elevated thunderstorms throughout the morning and early afternoon led to numerous lightning strikes and damage to transformers in Spokane.

Flash Flood in CHELAN, WASHINGTON
From 29-JUN-13 13:25:00 to 29-JUN-13 14:30:00 (PST-8)
Location: WEST WENATCHEE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

In the city of Wenatchee, Miller, Western, Springwater, and McKittrick roads experienced flooding.  Manhole covers were blown off along Miller Street between Millerdale Avenue and Springwater Avenue.  Sections of these roads were closed for roughly one hour as one to two feet of water filled some intersections.  Mud and water could be seen flowing across State Route 28 at the junction of US2 and US97 via a DOT camera on the northern sections of Wenatchee.  The water and mud was estimated to be less then a foot deep.  A CoCoRahs report from one mile west southwest of Wenatchee stated the lower level of their outbuilding was flooded however it is unknown if there was any damage.

Lightning in SPOKANE, WASHINGTON
From 29-JUN-13 14:45:00 to 29-JUN-13 15:15:00 (PST-8)
Location: SPOKANE
Property damage: 6.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Lightning struck a house on Spokane's South Hill starting a fire.  Firefighters were able to quickly extinguish the fire but the home did sustain heavy fire damage to a small portion of the attic and to the ceiling in one second floor bedroom.

Debris Flow in CHELAN, WASHINGTON
From 29-JUN-13 16:05:00 to 29-JUN-13 17:00:00 (PST-8)
Location: BLEWETT
Flood cause: Heavy Rain / Burn Area
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

High intensity rainfall on the 2012 Peavine burn scar caused a flash flood and debris flow in Tronsen Creek and across Upper Tronsen Road.  The culvert under Upper Tronsen Road was clogged with eight feet of debris and the creek now flows over the road.  Several large boulders were also deposited along the road.  On the eastern periphery of the Peavine burn scar, a large debris flow occurred in Devils Gulch.  A long segment of a USFS trail was wiped out.  Several hundred feet of the trail was covered in downed trees carried by the debris flow.

Lightning in SPOKANE, WASHINGTON
From 29-JUN-13 11:00:00 to 29-JUN-13 12:00:00 (PST-8)
Location: FT WRIGHT
Property damage: 4.00K
Crop damage: 0.00K
Reported by: Public

Lightning struck a transformer box in an alley behind a residential house, traveled through the lines and blew out a second transformer.  Several homes loss power that afternoon until utility companies were able to replace the transformers.  The transformers were located between Broadway and Boone Streets in west Spokane.  The exact time of the lightning strike was estimated.