Alert archive / Oregon / Flash Flood Warnings in 2012

Flash Flood Warning 3, NWS Pendleton, OR

July 17, 2012Umatilla County, Union County, Wallowa County, Oregon

NWS Pendleton, OR issued this flash flood warning at Jul 17, 2012, 5:08 PM PDT for Umatilla County, Union County, Wallowa County, Oregon. It was in force for 112 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 17, 2012, 5:08 PM PDT (00:08 UTC)
Expired: Jul 17, 2012, 7:00 PM PDT
In force: 112 min
Issued by: NWS Pendleton, OR
Area: Storm-based polygon
Flood severity: None

Counties Umatilla County, OR, Union County, OR, Wallowa County, OR

The radar

The Pendleton radar (KPDT), 82 km from the middle of the area, began a volume at 00:10 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

Spokane, WA (KOTX), launched 00:00Z, 0.1 hours before the alert went out and 239 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: 449 J/kg
Mixed-layer CIN: -97 J/kg
Mixed-layer LCL: 1747 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

020 
WGUS56 KPDT 180008
FFWPDT
ORC059-061-063-180200-
/O.NEW.KPDT.FF.W.0003.120718T0008Z-120718T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PENDLETON OR
508 PM PDT TUE JUL 17 2012

THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL UMATILLA COUNTY IN NORTHEAST OREGON...
  NORTH CENTRAL UNION COUNTY IN NORTHEAST OREGON...
  NORTHWESTERN WALLOWA COUNTY IN NORTHEAST OREGON...

* UNTIL 700 PM PDT

* AT 500 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
FLASH FLOODING FROM THUNDERSTORMS OVER THE WARNED AREA. RADAR 
INDICATED RAIN RATES OF 1.5 TO 2 INCHES. MORE RAIN IS EXPECTED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE
POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS
FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF
SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.

&&

LAT...LON 4599 11773 4572 11736 4545 11792 4574 11828

$$

DC

1 follow-up statement

789 
WGUS76 KPDT 180154
FFSPDT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PENDLETON OR
654 PM PDT TUE JUL 17 2012

ORC059-061-063-180202-
/O.EXP.KPDT.FF.W.0003.000000T0000Z-120718T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
UNION OR-WALLOWA OR-UMATILLA OR-
654 PM PDT TUE JUL 17 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 700 PM PDT FOR EAST CENTRAL
UMATILLA...NORTHWESTERN WALLOWA AND NORTH CENTRAL UNION COUNTIES...

HEAVY RAIN HAS ENDED. FLASH FLOODING IS NO LONGER EXPECTED.

LAT...LON 4599 11773 4572 11736 4545 11792 4574 11828

$$

DC

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 5:14 PM PDT	Severe Thunderstorm Warning	PDT	Umatilla, Union, Wallowa	61 min
Jul 17, 5:43 PM PDT	Flash Flood Warning	PDT	Gilliam, Morrow	108 min
Jul 17, 5:48 PM PDT	Severe Thunderstorm Warning	PDT	Gilliam, Morrow, Sherman	42 min
Jul 18, 3:40 PM PDT	Special Weather Statement	PDT	Union	35 min
Jul 18, 4:10 PM PDT	Severe Thunderstorm Warning	PDT	Umatilla, Union, Wallowa	65 min

Nearby

Flash Flood Warnings in Oregon, 2012 Every flash flood warning in 2012

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.