Alert archive / Oregon / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 53, NWS Pendleton, OR

July 30, 1997Morrow County, Umatilla County, Oregon

NWS Pendleton, OR issued this severe thunderstorm warning at Jul 30, 1997, 7:49 PM PDT for Morrow County, Umatilla County, Oregon. It was in force for 56 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 30, 1997, 7:49 PM PDT (02:49 UTC)
Expired
Jul 30, 1997, 8:45 PM PDT
In force
56 min
Issued by
NWS Pendleton, OR
Area
Whole counties

Counties Morrow County, OR, Umatilla County, OR

The nearest sounding before it

Salem/Mcnary, OR (KSLE), launched 00:00Z, 2.8 hours before the alert went out and 308 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 00:00Z on 1997-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 1997-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1768 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Jul 30, 2:04 PM PDT, 5 hours 45 minutes earlier.

Area forecast discussion, Jul 30, 2:04 PM PDT, 5 hours 45 minutes before
NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
200 PM PDT WED JUL 30 1997

JUST REACHED CONVECTIVE TEMP AT KPDT.  TS FORMING IN S PORTION OF
CWFA ATTM.  WK THCKNS DIFFLUENCE EVIDENT IN 15Z MESO ETA MODEL BUT
LTL IF ANY CONVECTIVE PCPN PROGD BY MODEL.  700MB WIND ON KPDT 88D
20-25KTS WHICH IS NOT CONDUCIVE TO FF SO WILL LET PREVIOUS SPS
HANDLE SITUATION.  LOW LEVEL SHEAR HAS INCREASED SINCE MORN
DISCUSSION SO CHC FOR GR BETTER.

INSTABILITY IN MODELS CONTINUES AFT 06Z FOR E SIDE SO
NOCTURNAL TS POSSIBLE UNTIL MIDNIGHT.  THU IS DRYER ACCORDING TO
MODELS....HOWEVER MODELS HAVE UNDERESTIMATED MSTR LAST TWO
DAYS.  FLO SWLY BUT UNSTABLE AGAIN THU E SIDE SO WILL CONT TS IN
FORECAST.  AVN SHOWS WK VORT CNTR ACROSS NE ORE/SE WA FRI SO CANNOT
RULE OUT MORE CONVECTION E MTNS AGAIN FRI AFTN.  LTL CHG IN TEMPS
THRU FRI.  PDT/ALW WILL CLIMB TO ABOUT 87F TODAY AND THU SAME OR
LTL WARMER.  WILL GO ABV FWCPDT/ALW FOR THU AFTN.

EXTDD...SWLY FLO THRU MON.  MOCLR SKIES DURING PERIOD EXCEPT FOR
CHC AFTN/EVE MTN TS.  TEMPS LTL BLO SEASONAL NORMS DURING PERIOD.
SB

PDT 5221  ALW 5221  PSC 3111  YKM 2111

.KPDT...VCP21/CSR21...OPERATIONAL.h

.KPDT...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 5:06 PM PDTSevere Thunderstorm WarningPDTUmatilla69 min
Jul 30, 5:29 PM PDTSevere Thunderstorm WarningPDTWasco2 hr
Jul 30, 6:05 PM PDTSevere Thunderstorm WarningPDTUmatilla55 min
Jul 30, 6:41 PM PDTSevere Thunderstorm WarningPDTMorrow, Umatilla64 min
Jul 30, 7:22 PM PDTSevere Thunderstorm WarningPDTWasco68 min
Jul 30, 8:30 PM PDTFlash Flood WarningPDTMorrow, Umatilla60 min
Jul 30, 9:24 PM PDTFlash Flood WarningPDTMorrow, Umatilla96 min
Jul 31, 2:50 PM PDTSevere Thunderstorm WarningPDTCrook, Deschutes40 min
Jul 31, 3:15 PM PDTSevere Thunderstorm WarningPDTUmatilla, Union45 min
Jul 31, 3:30 PM PDTSevere Thunderstorm WarningPDTCrook, Jefferson60 min
Jul 31, 4:00 PM PDTSevere Thunderstorm WarningPDTUmatilla, Union60 min
Jul 30, 6:54 PM PDTSevere Thunderstorm WarningPDTColumbia, Walla Walla51 min
Jul 30, 6:58 PM PDTSevere Thunderstorm WarningPDTColumbia, Walla Walla47 min
Jul 30, 8:55 PM PDTFlash Flood WarningPDTBenton, Franklin, Walla Walla2 hr
Jul 30, 9:38 PM PDTFlash Flood WarningPDTColumbia, Franklin, Walla Walla82 min
Jul 30, 9:38 PM PDTSevere Thunderstorm WarningPDTColumbia, Franklin, Walla Walla82 min

Nearby

Severe Thunderstorm Warnings in Oregon, 1997Every severe thunderstorm warning in 1997

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.