Alert archive / Oregon / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Boise, ID

July 31, 2021Baker County, Oregon

NWS Boise, ID issued this flash flood warning at Jul 31, 2021, 4:48 PM PDT for Baker County, Oregon. It was in force for 2 hr. 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 31, 2021, 4:48 PM PDT (23:48 UTC)
Expired
Jul 31, 2021, 7:01 PM PDT
In force
2 hr
Issued by
NWS Boise, ID
Area
Storm-based polygon
Flood severity
None

County Baker County, OR

The radar

The Pendleton radar (KPDT), 113 km from the middle of the area, began a volume at 23:49 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

Boise Airport, ID (KBOI), launched 12:00Z, 11.8 hours before the alert went out and 212 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-pSkew-T log-p diagram, Boise Airport, ID at 12:00Z on 2021-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 172 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Boise Airport, ID at 12:00Z on 2021-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
172 J/kg
Mixed-layer CIN
-246 J/kg
Mixed-layer LCL
1811 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
60 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

046 
WGUS55 KBOI 312348
FFWBOI
ORC001-010245-
/O.NEW.KBOI.FF.W.0001.210731T2348Z-210801T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boise ID
448 PM PDT Sat Jul 31 2021

The National Weather Service in Boise has issued a

* Flash Flood Warning for...
  West Central Baker County in northeastern Oregon...

* Until 745 PM PDT.

* At 448 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 1.5 inches of 
  rain have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Sumpter, Larch Summit, Antlers Forest Service Station.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

&&

LAT...LON 4487 11822 4480 11809 4469 11807 4468 11810
      4463 11818 4457 11822 4471 11846 4472 11844
      4472 11843 4473 11839 4475 11837 4474 11832
      4475 11829 4477 11828 4480 11830 4481 11830
      4484 11832 4485 11829 4487 11829 4486 11824

FLASH FLOOD...RADAR INDICATED

$$

BOI
1 follow-up statement
686 
WGUS75 KBOI 010201
FFSBOI

Flash Flood Statement
National Weather Service Boise ID
701 PM PDT Sat Jul 31 2021

ORC001-010211-
/O.CAN.KBOI.FF.W.0001.000000T0000Z-210801T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Baker OR-
701 PM PDT Sat Jul 31 2021

...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL BAKER COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

A Flash Flood Watch remains in effect until 500 PM PDT Monday for 
portions of Idaho and Oregon.

LAT...LON 4487 11822 4480 11809 4469 11807 4468 11810
      4463 11818 4457 11822 4471 11846 4472 11844
      4472 11843 4473 11839 4475 11837 4474 11832
      4475 11829 4477 11828 4480 11830 4481 11830
      4484 11832 4485 11829 4487 11829 4486 11824

$$

BOI

Nearby

Flash Flood Warnings in Oregon, 2021Every 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.