Alert archive / Idaho / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 9, NWS Pocatello, ID

July 15, 20214 counties in Idaho

NWS Pocatello, ID issued this severe thunderstorm warning at Jul 15, 2021, 6:44 PM MDT for 4 counties in Idaho. It was in force for 46 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 15, 2021, 6:44 PM MDT (00:44 UTC)
Expired: Jul 15, 2021, 7:30 PM MDT
In force: 46 min
Issued by: NWS Pocatello, ID
Area: Storm-based polygon
Damage threat: Considerable
Hail: 0.75 in
Wind: 70.0 mph

Counties Clark County, ID, Fremont County, ID, Jefferson County, ID, Madison County, ID

The radar

The Pocatello radar (KSFX), 135 km from the middle of the area, began a volume at 00:47 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.

What was reported inside it

Time	Report	Where	Remark
Jul 15, 7:23 PM MDT	TSTM WND GST 48	15 N Parker, ID	MESONET STATION GASI1 - GAS CAVES.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 0.7 hours before the alert went out and 310 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3496 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 139 m²/s²
0-3 km storm-relative helicity: 217 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

308 
WUUS55 KPIH 160044
SVRPIH
IDC033-043-051-065-160130-
/O.NEW.KPIH.SV.W.0009.210716T0044Z-210716T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pocatello ID
644 PM MDT Thu Jul 15 2021

The National Weather Service in Pocatello has issued a

* Severe Thunderstorm Warning for...
  Fremont County in southeastern Idaho...
  Jefferson County in southeastern Idaho...
  Madison County in southeastern Idaho...
  Clark County in southeastern Idaho...

* Until 730 PM MDT.

* At 642 PM MDT, severe thunderstorms were located along a line
  extending from near Kilgore to 10 miles northeast of Hamer to 7
  miles northwest of Monteview, moving southeast at 40 mph.

  HAZARD...70 mph wind gusts.

  SOURCE...Mesonet. At 630 PM, 64mph winds were reported at the 
           China Point mesonet station. 

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Rexburg, Rigby, Ashton, Dubois, Idmon, Terreton, Marysville,
  Lorenzo, Sugar City, Menan, Teton, Roberts, Lewisville, Mud Lake,
  Parker, Hamer, Spencer, Archer, Egin and Kilgore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.

&&

LAT...LON 4430 11114 4367 11158 4365 11247 4422 11276
      4439 11244 4448 11211 4453 11179
TIME...MOT...LOC 0042Z 302DEG 34KT 4445 11181 4404 11205 4398 11266 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

JKeyes

2 follow-up statements

477 
WWUS55 KPIH 160110
SVSPIH

Severe Weather Statement
National Weather Service Pocatello ID
710 PM MDT Thu Jul 15 2021

IDC033-043-051-065-160130-
/O.CON.KPIH.SV.W.0009.000000T0000Z-210716T0130Z/
Fremont ID-Jefferson ID-Madison ID-Clark ID-
710 PM MDT Thu Jul 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR SOUTHERN FREMONT...JEFFERSON...MADISON AND SOUTH CENTRAL CLARK
COUNTIES...

At 709 PM MDT, severe thunderstorms were located along a line
extending from 8 miles south of Island Park Reservoir to Sugar City
to near Terreton, moving southeast at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Rexburg, Rigby, Ashton, Terreton, Marysville, Lorenzo, Sugar City,
Menan, Teton, Roberts, Lewisville, Mud Lake, Parker, Hamer, Archer,
Egin, St Anthony, Monteview, Plano and Chester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.

&&

LAT...LON 4430 11114 4367 11158 4365 11247 4405 11259
      4405 11217 4420 11167 4441 11157
TIME...MOT...LOC 0109Z 304DEG 32KT 4428 11154 4387 11179 4381 11239 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JKeyes

236 
WWUS55 KPIH 160126
SVSPIH

Severe Weather Statement
National Weather Service Pocatello ID
726 PM MDT Thu Jul 15 2021

IDC033-043-051-065-160135-
/O.EXP.KPIH.SV.W.0009.000000T0000Z-210716T0130Z/
Fremont ID-Jefferson ID-Madison ID-Clark ID-
726 PM MDT Thu Jul 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN FREMONT...
JEFFERSON...MADISON AND SOUTH CENTRAL CLARK COUNTIES WILL EXPIRE AT
730 PM MDT...
            
The storms and outflow winds which prompted the warning have 
weakened below severe limits, and no longer pose an immediate threat 
to life or property. Therefore, the warning will be allowed to 
expire. However gusty winds and heavy rain are still possible with 
these thunderstorms.

LAT...LON 4430 11114 4367 11158 4365 11247 4405 11259
      4405 11217 4420 11167 4441 11157
TIME...MOT...LOC 0125Z 302DEG 34KT 4421 11138 4380 11163 4374 11223 

$$

JKeyes

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 16, 3:29 AM MDT	Excessive Heat Watch	PIH	Bannock, Bingham, Blaine, Bonneville, Butte, Caribou and 9 more	24 hr
Jul 16, 4:10 PM MDT	Special Weather Statement	PIH	Oneida	50 min
Jul 16, 4:36 PM MDT	Special Weather Statement	PIH	Bannock	39 min
Jul 16, 4:40 PM MDT	Special Weather Statement	PIH	Power	50 min

Nearby

Severe Thunderstorm Warnings in Idaho, 2021 Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.