Alert archive / Oregon / Flash Flood Warnings in 1998

Flash Flood Warning 13, NWS Pendleton, OR

July 27, 1998Jefferson County, Oregon

NWS Pendleton, OR issued this flash flood warning at Jul 27, 1998, 2:13 PM PDT for Jefferson County, Oregon. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 27, 1998, 2:13 PM PDT (21:13 UTC)
Expired
Jul 27, 1998, 3:15 PM PDT
In force
62 min
Issued by
NWS Pendleton, OR
Area
Whole counties

County Jefferson County, OR

The radar

The Portland,OR radar (KRTX), 185 km from the middle of the area, began a volume at 21:16 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

Salem/Mcnary, OR (KSLE), launched 12:00Z, 9.2 hours before the alert went out and 148 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, Salem/Mcnary, OR at 12:00Z on 1998-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 860 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Salem/Mcnary, OR at 12:00Z on 1998-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
860 J/kg
Mixed-layer CIN
-450 J/kg
Mixed-layer LCL
1574 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPDT 272113
FFWPDT
ORC031-272215-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PENDLETON OR
213 PM PDT MON JUL 27 1998

THE NATIONAL WEATHER SERVICE IN PENDLETON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN JEFFERSON IN NORTH CENTRAL OREGON

* UNTIL 315 PM PDT

* AT 200 PM... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH VERY HEAVY RAIN 20 EAST OF MADRAS.

* A SLOW MOVING THUNDERSTORM IS PRODUCING HEAVY RAIN IN SOUTHEAST
  JEFFERSON COUNTY.  DOPPLER RADAR ESTIMATES THAT THIS THUNDERSTORM
  HAS PRODUCED OVER ONE INCH OF RAINFALL IN THE PAST HOUR.

A THUNDERSTORM CAN CAUSE FLASH FLOODING MANY MILES FROM WHERE
THE STORM IS OCCURING.   KEEP CHILDREN AWAY FROM STREAMS AND CREEKS
AS WELL AS STORM DRAINS...VIADUCTS AND OTHER LOW LYING AREAS SUBJECT
TO FLOODING.

SMITH

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Pendleton, OR wrote its last area forecast discussion before this flash flood warning went out at Jul 27, 1:46 PM PDT, 27 minutes earlier.

Area forecast discussion, Jul 27, 1:46 PM PDT, 27 minutes before
NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION...
NATIONAL WEATHER SERVICE PENDLETON OR       CORRECTED FOR FIRE
200 AM PDT MON JUL 27 1998                  WEATHER INFORMATION

THUNDERSTORMS ARE FLARING UP ACROSS THE CWA THIS AFTERNOON IN...
MOSTLY IN THE CENTRAL/NORTHEAST OREGON MOUNTAINS AND OTHERS OVER
THE CASCADES.  DEW POINTS ARE ABOUT 5 DEGREES HIGHER THAN ON SUNDAY
WITH PRECIP WATER IN THE .75 TO 1.00 INCH...WHICH IS SIMILAR TO
SUNDAY.  CAPES ARE HIGHEST ALONG THE CASCADES TODAY/TUE WITH
MODIFIED SOUNDINGS SHOWING LIFTED INDICES IN THE NEGATIVE SINGLE
DIGITS.  LOOKS LIKE THUNDERSTORMS THIS EVENING ARE A GOOD FORECAST
AND WILL INCREASE POPS TO CHANCE IN MOUNTAINS...ISOLATED ELSEWHERE.
FOR TUESDAY...ATMOSPHERE BECOMES EVEN MORE UNSTABLE AS AN UPPER
TROUGH OFF THE NORTHWEST COAST ADVANCES CLOSER TO THE REGION.
850MB TEMPS REMAIN IN THE UPPER 20S TO NEAR 30 DEGREES C...HOWEVER
MORE CLOUD COVER MAY KEEP TEMPS DOWN A FEW DEGREES TUE.  KPDT WAS
102 AT 1PM...SO TEMPS SHOULD BE AT LEAST CLOSE TO THE CENTURY MARK
AGAIN IN THE FOOTHILLS OF THE BLUES AND A FEW DEGREES OVER IN THE
COLUMBIA BASIN.  UPPER TROUGH WILL THEN MOVE INTO THE CWA BY LATE
WEDNESDAY AND WEDNESDAY NIGHT.  LOOKS LIKE A ROUND OF POSSIBLE
SEVERE WEATHER ON THE HORIZON FOR WEDNESDAY AS DIFFLUENCE ALOFT
COMBINED WITH INCREASED CONVECTIVE INSTABILITY MOVES INTO THE CWA.

EXTENDED...FINALLY SOME COOLER TEMPERATURES WITH BREEZY CONDITIONS
AND A CHANCE OF SHOWERS FOR THE REST OF THE WEEK INTO THE WEEKEND
AS THE UPPER TROUGH DEEPENS AND MOVE ACROSS THE PACIFIC NORTHWEST.

FIRE WEATHER...A FIRE WEATHER WATCH HAS BEEN ISSUED FOR THE FIRE
WEATHER DISTRICT FOR POSSIBLE DRY LIGHTNING THIS AFTERNOON/EVENING
AND AGAIN ON TUESDAY.  MOST STORMS WILL BE WET...HOWEVER WITH THE
ATMOSPHERE BEING SO HOT WITH HUMIDITIES IN THE TEENS AND 20S A FEW
DRY STRIKES ARE NOT RULED OUT.  RSC.

PDT 2223  ALW 2223  PSC 1222  YKM 1222

.KPDT-88D...VCP31/CSR21.

.KPDT...NONE.

Nearby

Flash Flood Warnings in Oregon, 1998Every flash flood warning in 1998

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.