Alert archive / Oregon / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Medford, OR

July 30, 2021Josephine County, Oregon

NWS Medford, OR issued this flash flood warning at Jul 30, 2021, 5:16 PM PDT for Josephine County, Oregon. It was in force for 59 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 30, 2021, 5:16 PM PDT (00:16 UTC)
Expired: Jul 30, 2021, 6:15 PM PDT
In force: 59 min
Issued by: NWS Medford, OR
Area: Storm-based polygon
Flood severity: None

County Josephine County, OR

The radar

The Medford radar (KMAX), 64 km from the middle of the area, began a volume at 00:21 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 0.3 hours before the alert went out and 67 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 56 J/kg
Mixed-layer CIN: -307 J/kg
Mixed-layer LCL: 3581 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: -11 m²/s²
0-3 km storm-relative helicity: 32 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

528 
WGUS56 KMFR 310016
FFWMFR
ORC033-310115-
/O.NEW.KMFR.FF.W.0002.210731T0016Z-210731T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Medford OR
516 PM PDT Fri Jul 30 2021

The National Weather Service in Medford has issued a

* Flash Flood Warning for...
  The Slater burn scar in...
  South Central Josephine County in southwestern Oregon...

* Until 615 PM PDT.

* At 516 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain over the Slater Burn Scar. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms in and around
           the Slater Burn Scar.

  SOURCE...Radar.

  IMPACT...Flooding of areas in and around the Slater Burn Scar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a life threatening situation. Heavy rainfall could cause 
extensive and severe flash flooding of creeks...streams...and 
ditches in the Slater Burn Scar. Severe debris flows can also be 
anticipated across roads. Roads and driveways may be washed away in 
places. If you encounter flood waters...climb to safety.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4210 12352 4208 12352 4206 12352 4206 12349
      4207 12349 4209 12348 4207 12343 4206 12343
      4206 12339 4204 12338 4203 12340 4201 12339
      4200 12359 4202 12357 4203 12358 4204 12358
      4206 12355 4211 12355

FLASH FLOOD...RADAR INDICATED

$$

Smith

1 follow-up statement

477 
WGUS76 KMFR 310112
FFSMFR

Flash Flood Statement
National Weather Service Medford OR
612 PM PDT Fri Jul 30 2021

ORC033-310122-
/O.EXP.KMFR.FF.W.0002.000000T0000Z-210731T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Josephine OR-
612 PM PDT Fri Jul 30 2021

...FLASH FLOOD WARNING FOR THE SLATER BURN SCAR WILL EXPIRE AT 615 
PM PDT THIS EVENING FOR SOUTH CENTRAL JOSEPHINE COUNTY...

The heavy rain has ended.

LAT...LON 4210 12352 4208 12352 4206 12352 4206 12349
      4207 12349 4209 12348 4207 12343 4206 12343
      4206 12339 4204 12338 4203 12340 4201 12339
      4200 12359 4202 12357 4203 12358 4204 12358
      4206 12355 4211 12355

$$

Smith

The office that day

Everything else NWS Medford, OR issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 31, 1:55 PM PDT	Red Flag Warning	MFR	Curry, Douglas, Jackson, Josephine, Klamath, Lake	32 hr

Nearby

Flash Flood Warnings in Oregon, 2021 Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.