A wet spring season resulted in saturated soils across the Inland Northwest.  Rivers, small streams, and creeks began to rise as warming temperatures on May 13th and 14th melted mountain snowpack across the east slopes of the northern Cascades and Northeast Mountains.  Warm and dry weather transitioned to cooler but considerably wetter conditions over the weekend May 14th and 15th.  An upper level low pumped a considerable amount of moisture into the region with an extended period of heavy rainfall over the Cascades to the Okanogan Highlands early Saturday morning through Sunday morning.  This heavy rainfall slowly pushed to the northeast into the Spokane Area and Northeast Mountains by Sunday afternoon into Monday.  Forty-eight hour rainfall totals ranged from one to three inches across the east slopes of the northern Cascades, one to one and a half inches across the Spokane Area, to one to two and a quarter inches across the Northeast mountains.  In addition to the flooding, landslides were reported, and even a few trees were downed as winds picked up across the Okanogan Highlands Saturday morning.

Flood in CHELAN, WASHINGTON
From 15-MAY-11 09:45:00 to 16-MAY-11 05:00:00 (PST-8)
Location: MALAGA
Flood cause: Heavy Rain / Snow Melt
Property damage: 20.00K
Crop damage: 0.00K
Reported by: County Official

Heavy rain and snow melt resulted in flooding along Colockum Road.  Kingsbury Bridge was undercut by Colockum Creek resulting in its closer.  Further down the creek flooding was reported on Tarpiscan Road, which blocked vehicle access to the Washington State University agricultural research station.  Colockum Creek flowed in the basement of a rental home, forcing the renters to evacuate.  Property damage was estimated.

Debris Flow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 14-MAY-11 12:00:00 to 14-MAY-11 12:20:00 (PST-8)
Crop damage: 0.00K
Reported by: Park/Forest Service

Mud and debris flowed into Lake Chelan down the Meadow Creek drainage.  A section of the Lakeshore Trail was damaged during the landslide.  Estimated the timing of the slide as it was reported to have occurred sometime either the 14th or the 15th.

Flood in STEVENS, WASHINGTON
From 12-MAY-11 13:00:00 to 17-MAY-11 15:00:00 (PST-8)
Location: CHEWELAH
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Chewelah Creek rose to bank level on May 12th resulting in portions of Chewelah Park being inundated with water next to the creek.  By May 16th, the creek had risen considerably out of its banks with flooding observed over Lincoln Avenue south of the park forcing its closure.  The creek continued to rise through May 17th at which time water began flowing over state route 395 between mile post 206.69 and 207.81 forcing its closure as well.  Flood waters approached businesses next to the park, but did not appear to make it inside any buildings.

Heavy Rain in SPOKANE, WASHINGTON
From 15-MAY-11 14:00:00 to 15-MAY-11 20:00:00 (PST-8)
Location: VELOX
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain Sunday resulted in water pooling on eastbound Interstate 90 at mile post 294.  Traffic was reduced to one lane starting Sunday night May 15th through Monday morning due to the flooding on the interstate.

Heavy Rain in SPOKANE, WASHINGTON
From 15-MAY-11 14:00:00 to 15-MAY-11 20:00:00 (PST-8)
Location: VELOX
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain resulted in water pooling on Flora Road in Spokane Valley resulting in its closure Sunday night May 15th.

Flood in SPOKANE, WASHINGTON
From 16-MAY-11 08:45:00 to 16-MAY-11 22:00:00 (PST-8)
Location: GREEN BLUFF
Flood cause: Heavy Rain / Snow Melt
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Broadcast Media

State Route 206 was undercut by Deadman Creek at mile post 14.5, which forced a temporary closure of the road.  Only damage that occurred was along the shoulder of the roadway.  Damage costs were estimated.

Flood in OKANOGAN, WASHINGTON
From 14-MAY-11 15:00:00 to 15-MAY-11 16:00:00 (PST-8)
Location: MAZAMA ARPT
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Lost River Road flooded approximately three miles east of Mazama as debris clogged the flow of water underneath a bridge.  Two feet of water was observed to be flowing over the roadway resulting in its closure.  No damage was reported to the road.

Strong Wind in OKANOGAN HIGHLANDS, WASHINGTON
From 13-MAY-11 23:50:00 to 14-MAY-11 05:30:00 (PST-8)
Magnitude: 33.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Department of Highways

The combination of saturated soils and strong winds resulted in two trees toppling over onto highway 14 east of Republic.  The first tree fell just after 2350PST on May 13th fourteen miles east of town and the second fell around 0430PST nine miles east of town.