Alert archive / Nebraska / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 122

May 7, 201416 counties in Colorado; 22 counties in Nebraska; Albany County, Laramie County, Wyoming

The Storm Prediction Center issued this severe thunderstorm watch at May 7, 2014, 12:37 PM MDT for 16 counties in Colorado; 22 counties in Nebraska; Albany County, Laramie County, Wyoming. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: May 7, 2014, 12:37 PM MDT (18:37 UTC)
Expired: May 7, 2014, 8:00 PM MDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 60 kt

All 40 counties

Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Jefferson County, CO, Larimer County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Arthur County, NE, Banner County, NE, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Kimball County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Scotts Bluff County, NE, Thomas County, NE, Albany County, WY, Laramie County, WY

The radar

The Cheyenne radar (KCYS), 103 km from the middle of the area, began a volume at 18:37 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: 20%
One or more EF2 to EF5 tornadoes: 2%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 90%
One or more hailstones of 2 inches or more: 50%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

54 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
May 7, 1:45 PM MDT	Severe Thunderstorm Warning	BOU	Larimer, Weld	45 min
May 7, 1:51 PM MDT	Tornado Warning	BOU	Weld	24 min
May 7, 1:51 PM MDT	Tornado Warning	BOU	Weld	24 min
May 7, 2:26 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Washington	49 min
May 7, 2:32 PM MDT	Severe Thunderstorm Warning	BOU	Weld	43 min
May 7, 2:33 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	27 min
May 7, 2:36 PM MDT	Severe Thunderstorm Warning	GLD	Kit Carson, Yuma	39 min
May 7, 2:39 PM MDT	Tornado Warning	BOU	Weld	36 min
May 7, 2:56 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	34 min
May 7, 3:00 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	45 min
May 7, 3:01 PM MDT	Severe Thunderstorm Warning	BOU	Weld	44 min
May 7, 3:04 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	41 min
May 7, 3:26 PM MDT	Severe Thunderstorm Warning	GLD	Kit Carson, Yuma	49 min
May 7, 3:27 PM MDT	Tornado Warning	BOU	Weld	33 min
May 7, 3:30 PM MDT	Tornado Warning	BOU	Washington	45 min
May 7, 3:37 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	38 min
May 7, 3:40 PM MDT	Severe Thunderstorm Warning	GLD	Dundy	65 min
May 7, 3:44 PM MDT	Severe Thunderstorm Warning	GLD	Yuma	61 min
May 7, 3:57 PM MDT	Severe Thunderstorm Warning	BOU	Washington	48 min
May 7, 4:00 PM MDT	Severe Thunderstorm Warning	BOU	Weld	30 min
May 7, 4:07 PM MDT	Severe Thunderstorm Warning	GLD	Hitchcock	53 min
May 7, 4:12 PM MDT	Severe Thunderstorm Warning	LBF	Hayes, Lincoln, Perkins	48 min
May 7, 4:13 PM MDT	Severe Thunderstorm Warning	GLD	Dundy	62 min
May 7, 4:15 PM MDT	Tornado Warning	BOU	Washington	45 min
May 7, 4:15 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	45 min
May 7, 4:26 PM MDT	Tornado Warning	BOU	Weld	34 min
May 7, 4:30 PM MDT	Severe Thunderstorm Warning	LBF	Lincoln	45 min
May 7, 4:44 PM MDT	Tornado Warning	GLD	Yuma	46 min
May 7, 4:50 PM MDT	Tornado Warning	BOU	Logan, Phillips, Washington	40 min
May 7, 4:52 PM MDT	Tornado Warning	BOU	Phillips	23 min
May 7, 4:57 PM MDT	Tornado Warning	BOU	Logan, Sedgwick	48 min
May 7, 5:00 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	45 min
May 7, 5:00 PM MDT	Severe Thunderstorm Warning	LBF	Hayes, Lincoln, Perkins	45 min
May 7, 5:01 PM MDT	Severe Thunderstorm Warning	LBF	Garden	59 min
May 7, 5:10 PM MDT	Tornado Warning	BOU	Phillips	35 min
May 7, 5:14 PM MDT	Severe Thunderstorm Warning	LBF	Garden	61 min
May 7, 5:15 PM MDT	Severe Thunderstorm Warning	GLD	Red Willow	45 min
May 7, 5:18 PM MDT	Severe Thunderstorm Warning	LBF	Hayes, Lincoln	42 min
May 7, 5:29 PM MDT	Tornado Warning	GLD	Yuma	46 min
May 7, 5:30 PM MDT	Severe Thunderstorm Warning	BOU	Boulder	45 min
May 7, 5:30 PM MDT	Tornado Warning Tornado observed	BOU	Logan, Phillips	30 min
May 7, 5:37 PM MDT	Severe Thunderstorm Warning	LBF	Keith	38 min
May 7, 5:38 PM MDT	Tornado Warning	BOU	Phillips, Sedgwick	37 min
May 7, 5:40 PM MDT	Severe Thunderstorm Warning	LBF	Garden	50 min
May 7, 5:46 PM MDT	Severe Thunderstorm Warning	LBF	Frontier, Hayes, Lincoln	44 min
May 7, 6:00 PM MDT	Tornado Warning	BOU	Phillips, Sedgwick	30 min
May 7, 6:02 PM MDT	Severe Thunderstorm Warning	LBF	Arthur, Garden, Keith	43 min
May 7, 6:15 PM MDT	Severe Thunderstorm Warning	LBF	Frontier	45 min
May 7, 6:26 PM MDT	Severe Thunderstorm Warning	LBF	Lincoln	49 min
May 7, 6:39 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	36 min
May 7, 6:51 PM MDT	Severe Thunderstorm Warning	BOU	Weld	24 min
May 7, 7:12 PM MDT	Severe Thunderstorm Warning	BOU	Weld	33 min
May 7, 7:21 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Jefferson	24 min
May 7, 7:44 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Boulder, Broomfield, Denver, Jefferson	31 min

Discussions around it

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

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 6.6 hours before the alert went out and 122 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: 97 J/kg
Mixed-layer CIN: -126 J/kg
Mixed-layer LCL: 776 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 29 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.

Issued	Product	Office	Counties	Lasted
May 6, 11:52 PM MDT	Mesoscale Discussion	SPC	Logan, Morgan, Phillips, Sedgwick, Weld	2 hr
May 7, 11:59 AM MDT	Mesoscale Discussion	SPC	Adams, Logan, Morgan, Phillips, Sedgwick, Washington and 2 more	2 hr
May 7, 4:05 PM MDT	Mesoscale Discussion	SPC	Adams, Arapahoe, Larimer, Logan, Morgan, Phillips and 4 more	85 min
May 6, 6:06 PM MDT	Mesoscale Discussion	SPC	Banner, Scotts Bluff	54 min
May 7, 5:54 PM MDT	Mesoscale Discussion	SPC	Adams, Antelope, Boone, Buffalo, Custer, Dawson and 15 more	66 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2014 Severe Thunderstorm Watches in Colorado, 2014 Severe Thunderstorm Watches in Wyoming, 2014 Every 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.