Alert archive / Idaho / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 52, NWS Pocatello, ID

September 18, 2014Cassia County, Oneida County, Power County, Idaho

NWS Pocatello, ID issued this severe thunderstorm warning at Sep 18, 2014, 2:17 PM MDT for Cassia County, Oneida County, Power County, Idaho. It was in force for 43 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: Sep 18, 2014, 2:17 PM MDT (20:17 UTC)
Expired: Sep 18, 2014, 3:00 PM MDT
In force: 43 min
Issued by: NWS Pocatello, ID
Area: Storm-based polygon

Counties Cassia County, ID, Oneida County, ID, Power County, ID

The radar

The Pocatello radar (KSFX), 83 km from the middle of the area, began a volume at 20:20 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

Elko, NV (KLKN), launched 12:00Z, 8.3 hours before the alert went out and 197 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: 27 J/kg
Mixed-layer CIN: -163 J/kg
Mixed-layer LCL: 2128 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

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 Pocatello, ID wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 18, 1:33 PM MDT, 44 minutes earlier.

Area forecast discussion, Sep 18, 1:33 PM MDT, 44 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE POCATELLO ID
133 PM MDT THU SEP 18 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY. REGIONAL SATELLITE IMAGERY WAS
SHOWING A SPLITTING UPPER TROUGH OVER THE PAC COAST EARLY THIS
AFTERNOON. WEAK TO MODEST INSTABILITY AND MOISTURE AVAILABILITY ARE
EXPECTED TO COMBINE WITH DEEP LAYER SHEAR EXTENDING FROM NE NEVADA
THROUGH SW MONTANA THIS AFTERNOON TO PRODUCE SCATTERED STRONG
THUNDERSTORM DEVELOPMENT. PRECIPITABLE VALUES OF .75 TO 1.00 INCHES
WILL SUPPORT BRIEF HEAVY RAIN...ALTHOUGH THE FLASH FLOODING THREAT
APPEARS TO BE MINIMAL AT THIS POINT DUE TO THE SPEED WITH WHICH THE
CELLS WILL LIKELY BE MOVING. WINDEX VALUES UP TO 40 COMBINED WITH
AMBIENT BREEZY CONDITIONS MAY PRODUCE WIND GUSTS OF 40 TO 50 MPH
WITH THUNDERSTORMS THIS AFTERNOON/EARLY EVE. AT THIS POINT...THE
FAVORED AREAS FOR STRONGEST DEVELOPMENT APPEARS TO BE THE MACKAY TO
DILLON CORRIDOR AND MALTA TO CHESTERFIELD CORRIDOR. THE SRN PORTION
OF INCOMING TROUGH SPLITS FROM THE NRN BRANCH FLOW TONIGHT AS IT
DRIFTS SOUTH INTO CNTRL CALIFORNIA. THE LOCATION OF LOW AND
ASSOCIATED DYNAMICS/MOISTURE WILL PROMOTE ONGOING SHOWERS/CONVECTION
OVER SE IDAHO LATE TONIGHT. THE NRN BRANCH TROUGH AXIS SWEEPS
THROUGH THE REGION FRIDAY BRINGING A DISTINCT DRYING TREND TO THE
AREA. HUSTON

.LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY. THE UPPER LOW
DRIFTS SOUTH INTO THE SRN CALIFORNIA COASTAL AREA SATURDAY BEFORE
LIFTING NE INTO NEVADA LATE SATURDAY NIGHT WITH ATTENDING
PRECIPITATION SHIELD OVERSPREADING SE IDAHO SUNDAY AND CONTINUING
THROUGH MONDAY AS THE LOW WORKS EAST INTO WYOMING (PER THE GFS). THE
ECMWF (00Z) HAS A SIMILAR DEPICTION BUT IS MUCH MORE PROLIFIC WITH
PRECIPITATION PRODUCTION. FAVORING THE GFS SOLUTION IN THIS REGARD.
DRY CONDITIONS ARE EXPECTED BEHIND THE EXITING LOW AS THE NEXT PAC
TROUGH SPREADS INTO THE NW COASTAL WATERS TUESDAY/WEDNESDAY. BY
THURSDAY...THE MODELS BEGIN TO SHOW THE TROUGH WORKING INLAND...THE
ECMWF ADVERTISING ANOTHER SPLITTING TROUGH AND THE GFS SOMEWHAT MORE
CONSOLIDATED INITIALLY (THURSDAY) BUT QUICKLY TRENDING TOWARD A
SPLITTING SOLUTION FRIDAY. SPLITTING THE DIFFERENCE HERE (NO PUN
INTENDED) UNTIL MODELS SHOW SOME CONSOLIDATION...THUS CONTINUING
CLIMO-LOOKING PRECIP POTENTIAL THURSDAY/THURSDAY NIGHT. HUSTON
&&

.AVIATION...A STRONG UPPER JET IS BISECTING THE THE REGION THIS
AFTERNOON...WHICH IS PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS...BUT CONDITIONS WILL REMAIN VFR. EXPECT SOUTHWEST
WINDS GUSTING 20 TO 25 KTS IN THE SNAKE PLAIN THROUGH SUNSET.
TOMORROW WILL BE DRIER WITH ANOTHER BREEZY AFTERNOON.
&&

.FIRE WEATHER...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGHOUT THE REST OF TODAY. BREEZY CONDITIONS WILL REMAIN IN THE
SNAKE PLAIN THROUGH SUNSET. OVERNIGHT TONIGHT...SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS WILL REMAIN...MAINLY IN ZONE 413.
OTHERWISE...A DRYING TREND IS EXPECTED FRIDAY THROUGH AT LEAST
SUNDAY AFTERNOON.
&&

.PIH WATCHES/WARNINGS/ADVISORIES...NONE.
&&

In the hours before

Special weather statement, Sep 18, 1:07 PM MDT, 1 hour 10 minutes before

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Special weather statement, Sep 18, 1:34 PM MDT, 43 minutes before

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Special weather statement, Sep 18, 1:54 PM MDT, 23 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE POCATELLO ID
154 PM MDT THU SEP 18 2014

IDZ022-182100-
ONEIDA ID-CASSIA ID-
154 PM MDT THU SEP 18 2014

THE NATIONAL WEATHER SERVICE IN POCATELLO HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  SOUTHEASTERN CASSIA COUNTY IN SOUTH CENTRAL IDAHO
  EXTREME WEST CENTRAL ONEIDA COUNTY IN SOUTHEAST IDAHO

AT 148 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 7 MILES SOUTHEAST OF ALMO..MOVING NORTHEAST AT 25
MPH.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 45 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH BRIEF HEAVY RAIN.

LOCATIONS IMPACTED THROUGH 300 PM MDT INCLUDE...
   AREA SOUTH OF MALTA...

LAT...LON 4204 11369 4247 11321 4224 11291 4199 11331
      4199 11362
TIME...MOT...LOC 1954Z 224DEG 20KT 4204 11352

HUSTON

Special weather statement, Sep 18, 2:17 PM MDT, 0 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE POCATELLO ID
217 PM MDT THU SEP 18 2014

IDZ019-020-182115-
CLARK ID-JEFFERSON ID-BINGHAM ID-BUTTE ID-
217 PM MDT THU SEP 18 2014

THE NATIONAL WEATHER SERVICE IN POCATELLO HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  EAST CENTRAL BUTTE COUNTY IN EAST CENTRAL IDAHO
  SOUTH CENTRAL CLARK COUNTY IN EASTERN IDAHO
  NORTHWESTERN BINGHAM COUNTY IN SOUTHEAST IDAHO
  WESTERN JEFFERSON COUNTY IN SOUTHEAST IDAHO

AT 212 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR SOUTHWEST INL...MOVING NORTHEAST AT 35 MPH.

SMALL HAIL...BRIEF HEAVY RAIN AND WIND GUSTS UP TO 50 MPH ARE
POSSIBLE WITH THIS STORM AS IT MOVES TOWARDS MUD LAKE.

LOCATIONS IMPACTED THROUGH 315 PM MDT INCLUDE...
   SOUTHEAST INL...
   NORTHWEST INL...
   MUD LAKE...

LAT...LON 4412 11249 4388 11213 4341 11286 4354 11304
TIME...MOT...LOC 2016Z 222DEG 29KT 4354 11287

HUSTON

The office that day

Everything else NWS Pocatello, ID issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 18, 1:07 PM MDT	Special Weather Statement	PIH	Caribou	53 min
Sep 18, 1:24 PM MDT	Severe Thunderstorm Warning	PIH	Bannock, Bingham, Bonneville, Caribou	36 min
Sep 18, 1:34 PM MDT	Special Weather Statement	PIH	Butte	56 min
Sep 18, 1:54 PM MDT	Special Weather Statement	PIH	Cassia	66 min
Sep 18, 1:56 PM MDT	Severe Thunderstorm Warning	PIH	Bingham, Bonneville, Caribou	49 min
Sep 18, 2:17 PM MDT	Special Weather Statement	PIH	Jefferson	58 min
Sep 18, 2:20 PM MDT	Special Weather Statement	PIH	Bonneville	55 min
Sep 18, 2:25 PM MDT	Special Weather Statement	PIH	Teton	50 min
Sep 18, 2:31 PM MDT	Special Weather Statement	PIH	Caribou	59 min
Sep 18, 2:42 PM MDT	Tornado Warning	PIH	Cassia, Oneida, Power	48 min
Sep 18, 3:26 PM MDT	Severe Thunderstorm Warning	PIH	Cassia, Oneida, Power	41 min
Sep 18, 3:38 PM MDT	Severe Thunderstorm Warning	PIH	Bannock, Oneida, Power	52 min
Sep 18, 4:11 PM MDT	Special Weather Statement	PIH	Oneida	49 min
Sep 18, 4:15 PM MDT	Severe Thunderstorm Warning	PIH	Bannock, Caribou	45 min
Sep 18, 4:27 PM MDT	Special Weather Statement	PIH	Bonneville	48 min
Sep 18, 4:35 PM MDT	Severe Thunderstorm Warning	PIH	Bannock, Franklin, Oneida, Power	40 min
Sep 18, 5:13 PM MDT	Severe Thunderstorm Warning	PIH	Bannock, Caribou, Oneida	19 min
Sep 18, 5:43 PM MDT	Special Weather Statement	PIH	Oneida	47 min

Nearby

Severe Thunderstorm Warnings in Idaho, 2014 Every severe thunderstorm warning in 2014

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.