A major severe weather event by Pacific Northwest standards occurred over central and northeast Oregon and southeast Washington on May 30th. A powerful upper level storm system moved across the area during the afternoon and evening helping to trigger severe thunderstorms. The airmass was unusually unstable for this area of the country with surface dewpoints well into the 60s. With strong upper level winds in place the stage was set for numerous fast moving intense storms through the afternoon and early evening. Numerous reports of large hail and damaging winds were received with most of the hail falling in central Oregon. There were multiple reports of significant hail (2 inch in diameter) and winds in excess of 75 mph. Winds were estimated as high as 115 mph in Wasco County, OR.

Thunderstorm Wind in SHERMAN, OREGON
From 30-MAY-20 14:48:00 to 30-MAY-20 14:50:00 (PST-8)
Location: GRASS VLY
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

Patjens RAWS measured gust.

Hail in DESCHUTES, OREGON
From 30-MAY-20 12:30:00 to 30-MAY-20 12:33:00 (PST-8)
Location: LA PINE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in DESCHUTES, OREGON
From 30-MAY-20 13:00:00 to 30-MAY-20 13:05:00 (PST-8)
Location: SUNRIVER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Also trees down in Sunriver.

Thunderstorm Wind in UMATILLA, OREGON
From 30-MAY-20 15:44:00 to 30-MAY-20 15:46:00 (PST-8)
Location: HERMISTON ARPT
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in UMATILLA, OREGON
From 30-MAY-20 15:43:00 to 30-MAY-20 15:49:00 (PST-8)
Location: UMATILLA
Magnitude: 65.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trees and powerlines down. Roof damage reported.

Hail in UMATILLA, OREGON
From 30-MAY-20 15:31:00 to 30-MAY-20 15:33:00 (PST-8)
Location: HOLDMAN
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in GILLIAM, OREGON
From 30-MAY-20 15:10:00 to 30-MAY-20 15:25:00 (PST-8)
Location: ARLINGTON
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WASCO, OREGON
From 30-MAY-20 14:30:00 to 30-MAY-20 14:35:00 (PST-8)
Location: SHANIKO
Magnitude: 100.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Other Federal Agency

Strong winds estimated at 100-115 mph downed portions of two high tension power towers.

Thunderstorm Wind in GILLIAM, OREGON
From 30-MAY-20 15:00:00 to 30-MAY-20 15:05:00 (PST-8)
Location: CONDON
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Tree down and damage to a home.

Hail in DESCHUTES, OREGON
From 30-MAY-20 13:34:00 to 30-MAY-20 13:36:00 (PST-8)
Location: TERREBONNE
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash Flood in WASCO, OREGON
From 30-MAY-20 13:00:00 to 30-MAY-20 14:00:00 (PST-8)
Location: PINE GROVE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Flash flooding and debris flow reported. 300 yard debris flow on BIA Route 6. 8 inches of water over roads near Warm Springs.

Hail in GRANT, OREGON
From 30-MAY-20 13:45:00 to 30-MAY-20 13:48:00 (PST-8)
Location: KIMBERLY
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in DESCHUTES, OREGON
From 30-MAY-20 12:50:00 to 30-MAY-20 12:53:00 (PST-8)
Location: LAPINE STATE ARPT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in DESCHUTES, OREGON
From 30-MAY-20 12:48:00 to 30-MAY-20 12:51:00 (PST-8)
Location: BEND
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in DESCHUTES, OREGON
From 30-MAY-20 12:34:00 to 30-MAY-20 12:39:00 (PST-8)
Location: LA PINE
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trees down and 1.00 inch hail.

Hail in UMATILLA, OREGON
From 30-MAY-20 15:13:00 to 30-MAY-20 15:15:00 (PST-8)
Location: PENDLETON
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in UMATILLA, OREGON
From 30-MAY-20 14:45:00 to 30-MAY-20 14:47:00 (PST-8)
Location: ECHO
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in SHERMAN, OREGON
From 30-MAY-20 14:52:00 to 30-MAY-20 14:54:00 (PST-8)
Location: RUFUS
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail in GRANT, OREGON
From 30-MAY-20 14:05:00 to 30-MAY-20 14:08:00 (PST-8)
Location: MONUMENT
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in DESCHUTES, OREGON
From 30-MAY-20 12:05:00 to 30-MAY-20 12:08:00 (PST-8)
Location: SISTERS
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in CROOK, OREGON
From 30-MAY-20 13:40:00 to 30-MAY-20 13:44:00 (PST-8)
Location: PRINEVILLE
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Thirty foot tall tree blown down.

Thunderstorm Wind in WASCO, OREGON
From 30-MAY-20 14:15:00 to 30-MAY-20 14:20:00 (PST-8)
Location: SHANIKO
Magnitude: 70.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Completely destroyed riverside camps along Deschutes River with debris everywhere.

Thunderstorm Wind in SHERMAN, OREGON
From 30-MAY-20 14:39:00 to 30-MAY-20 14:41:00 (PST-8)
Location: GRASS VLY
Magnitude: 62.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in MORROW, OREGON
From 30-MAY-20 14:40:00 to 30-MAY-20 14:42:00 (PST-8)
Location: BOARDMAN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Tree down in Boardman.

Thunderstorm Wind in JEFFERSON, OREGON
From 30-MAY-20 13:00:00 to 30-MAY-20 13:10:00 (PST-8)
Location: WARM SPGS
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Powerlines and trees down. Roof blown off house.

Thunderstorm Wind in UMATILLA, OREGON
From 30-MAY-20 15:30:00 to 30-MAY-20 15:33:00 (PST-8)
Location: HELIX
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail in UMATILLA, OREGON
From 30-MAY-20 16:10:00 to 30-MAY-20 16:13:00 (PST-8)
Location: HELIX
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in UMATILLA, OREGON
From 30-MAY-20 16:15:00 to 30-MAY-20 16:18:00 (PST-8)
Location: ADAMS
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in JEFFERSON, OREGON
From 30-MAY-20 13:29:00 to 30-MAY-20 13:45:00 (PST-8)
Location: CULVER
Magnitude: 87.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A concentrated swath of destructive straight line winds affected the Culver and Metolius areas of Jefferson County. Within this swath there were numerous large trees uprooted and snapped, hundreds of yards of irrigation line dislodged and/or mangled, and several snapped power poles. Some of the most significant damage included destruction of a handful of agricultural out buildings and partial or total roof removals of at least two manufactured homes.

Thunderstorm Wind in JEFFERSON, OREGON
From 30-MAY-20 13:45:00 to 30-MAY-20 14:00:00 (PST-8)
Location: MADRAS
Magnitude: 70.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple reports of trees down in Madras. Alfalfa crop destroyed by hail and strong winds.

Hail in JEFFERSON, OREGON
From 30-MAY-20 13:26:00 to 30-MAY-20 13:29:00 (PST-8)
Location: MADRAS
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Also 60-70 mph winds.

Hail in GRANT, OREGON
From 30-MAY-20 13:50:00 to 30-MAY-20 13:52:00 (PST-8)
Location: MONUMENT
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WALLOWA, OREGON
From 31-MAY-20 01:00:00 to 31-MAY-20 01:03:00 (PST-8)
Location: JOSEPH
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Nickle to quarter size hail covering the ground in Joseph.

Hail in WHEELER, OREGON
From 30-MAY-20 13:36:00 to 30-MAY-20 13:38:00 (PST-8)
Location: SPRAY
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in UMATILLA, OREGON
From 30-MAY-20 15:40:00 to 30-MAY-20 15:47:00 (PST-8)
Location: HERMISTON
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous trees and tree limbs down. One quarter mile visibility in blowing dust.