Alert archive / Idaho / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 72, NWS Missoula, MT

October 9, 1997Clearwater County, Idaho

NWS Missoula, MT issued this severe thunderstorm warning at Oct 9, 1997, 3:49 PM PDT for Clearwater County, Idaho. 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
Oct 9, 1997, 3:49 PM PDT (22:49 UTC)
Expired
Oct 9, 1997, 4:45 PM PDT
In force
56 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Clearwater County, ID

The radar

The Missoula radar (KMSX), 133 km from the middle of the area, began a volume at 22:51 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 12:00Z, 10.8 hours before the alert went out and 127 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, Spokane, WA at 12:00Z on 1997-10-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 1997-10-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -37 square meters per square second.193958Sfc1 km3 km6 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
803 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
-37 m²/s²
0-3 km storm-relative helicity
-59 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 KMSO 092253 RRA
SVRMSO
IDC035-092345-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
449 PM MDT (349 PM PDT) THU OCT 9 1997
 
THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  545 PM MDT (445 PM PDT)
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN NORTHEAST IDAHO
 
   ...CLEARWATER COUNTY
 
AT 345 PM PDT RADAR AND SEVERE WEATHER SPOTTERS INDICATED A SEVERE
THUNDERSTORM MOVING THROUGH WESTERN CLEARWATER COUNTY. THE STORM IS 5
MILES EAST OF OROFINO MOVING NORTHEAST AT 30 MPH. IT WILL APROACH THE
HEADQUATERS AND PIERCE AROUND 415 PM.
 
THIS STORM HAS A HISTORY OF PRODUCING ONE INCH DIAMETER HAIL.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON:'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
WHITMORE
 
&

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 Missoula, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Oct 9, 12:41 PM PDT, 3 hours 8 minutes earlier.

Area forecast discussion, Oct 9, 12:41 PM PDT, 3 hours 8 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
141 PM MDT THU OCT 9 1997

WATER VAPOR SHOWS STRONG VORTEX LOCATED OFF VANCOUVER ISLAND LIFTING
SLOWLY TOWARD THE EAST-NORTHEAST BUT MAINTAINING A MOIST
SOUTHWESTERLY FLOW OVER THE IDAHO PANHANDLE AND WESTERN MONTANA.
RADAR SHOWS DECREASED RAIN/SNOW ACTIVITY OVER THE PANHANDLE WITH
SCATTERED SHOWERS FILLING IN BEHIND EXITING JET AND DECREASING
DIFLUENCE. WILL LET ADVISORY EXPIRE FOR TODAY OVER NORTHWEST
MOUNTAINS. 12Z ETA INITIALIZIES PRETTY GOOD EXCEPT FOR LOWER-LEVEL
MOISTURE EAST OF THE DIVIDE. MODEL ALSO FORECAST FILLING AND
NORTHEAST PROGRESSION TO CONTINUE BUT THE BASE OF THE 5H TROF
REDEFINES AND DEEPENS ALONG THE COAST OVERNIGHT AS ANOTHER 130+ JET
BOLTS SOUTHWARD. FAIRLY WEAK VV UNDER SOUTHWEST CYCLONIC FLOW
SUPPORTS MOS/FAN SCATTERED POPS THROUGH SATURDAY. ALSO LITTLE
DEVIATION FOR HIGH AND LOW TEMPERATURES THROUGH THE PERIOD WITH NO
CHANGE IN AIR MASS UNTIL EARLY SATURDAY EVENING.

STOLL

LIB .. 039/046 038/046 ... 334334
FCA WW 038/048 037/048 031 335344
POL .. 043/049 042/049 ... 334333
MSO WW 039/052 038/047 034 334333
HMM .. 037/053 036/049 ... 333333
BTM .. 032/052 031/044 ... 334445
S80 .. 038/053 039/051 ... 334332
P69 .. 044/054 044/052 ... 333332
SMN .. 037/054 036/052 ... 333222

Nearby

Severe Thunderstorm Warnings in Idaho, 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; radar from the NEXRAD Level II archive.