Alert archive / Idaho / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 86

April 22, 201412 counties in Idaho; 8 counties in Montana; Lincoln County, Park County, Teton County, Wyoming

The Storm Prediction Center issued this severe thunderstorm watch at Apr 22, 2014, 2:28 PM MDT for 12 counties in Idaho; 8 counties in Montana; Lincoln County, Park County, Teton County, Wyoming. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 22, 2014, 2:28 PM MDT (20:28 UTC)
Expired
Apr 22, 2014, 8:12 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 23 counties

Bannock County, ID, Bear Lake County, ID, Bingham County, ID, Bonneville County, ID, Caribou County, ID, Clark County, ID, Franklin County, ID, Fremont County, ID, Jefferson County, ID, Madison County, ID, Oneida County, ID, Teton County, ID, Beaverhead County, MT, Broadwater County, MT, Gallatin County, MT, Madison County, MT, Meagher County, MT, Park County, MT, Sweet Grass County, MT, Wheatland County, MT, Lincoln County, WY, Park County, WY, Teton County, WY

The radar

The Pocatello radar (KSFX), 114 km from the middle of the area, began a volume at 20:28 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
70%

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 8.5 hours before the alert went out and 268 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, Riverton, WY at 12:00Z on 2014-04-22Temperature 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 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2014-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 183 square meters per square second.1939587897Sfc1 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
2539 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
183 m²/s²
0-3 km storm-relative helicity
228 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 22, 1:58 PM MDTMesoscale DiscussionSPCBannock, Bear Lake, Bingham, Bonneville, Butte, Caribou and 8 more2 hr
Apr 22, 4:20 PM MDTMesoscale DiscussionSPCBear Lake, Bonneville, Caribou, Franklin, Fremont, Madison and 1 more85 min
Apr 22, 4:14 PM MDTMesoscale DiscussionSPCGoshen, Laramie, Niobrara, Platte2 hr

Nearby

Severe Thunderstorm Watches in Idaho, 2014Severe Thunderstorm Watches in Montana, 2014Severe Thunderstorm Watches in Wyoming, 2014Every severe thunderstorm watch 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.