Alert archive / Colorado / Tornado Watches in 2019

Tornado Watch 264

May 27, 20199 counties in Colorado; Banner County, Cheyenne County, Kimball County, Nebraska; Goshen County, Laramie County, Platte County, Wyoming

The Storm Prediction Center issued this tornado watch at May 27, 2019, 12:56 PM MDT for 9 counties in Colorado; Banner County, Cheyenne County, Kimball County, Nebraska; Goshen County, Laramie County, Platte County, Wyoming. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
May 27, 2019, 12:56 PM MDT (18:56 UTC)
Expired
May 27, 2019, 8:47 PM MDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt

Counties Adams County, CO, Arapahoe County, CO, Denver County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Banner County, NE, Cheyenne County, NE, Kimball County, NE, Goshen County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 87 km from the middle of the area, began a volume at 18:56 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
60%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 27, 1:15 PM MDTSevere Thunderstorm WarningCYSLaramie45 min
May 27, 1:28 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan, Weld47 min
May 27, 1:34 PM MDTFlash Flood WarningCYSLaramie5 hr
May 27, 1:42 PM MDTTornado WarningBOUAdams33 min
May 27, 2:00 PM MDTSevere Thunderstorm WarningBOUMorgan45 min
May 27, 2:41 PM MDTSevere Thunderstorm WarningBOULogan, Morgan, Weld49 min
May 27, 2:43 PM MDTSevere Thunderstorm WarningCYSLaramie47 min
May 27, 2:50 PM MDTTornado WarningCYSGoshen, Laramie40 min
May 27, 3:03 PM MDTTornado Warning Tornado observedBOULogan, Morgan, Weld27 min
May 27, 3:27 PM MDTSevere Thunderstorm WarningCYSLaramie48 min
May 27, 3:30 PM MDTTornado Warning Tornado observedBOULogan30 min
May 27, 3:40 PM MDTSevere Thunderstorm WarningBOUWeld35 min
May 27, 3:59 PM MDTTornado WarningBOULogan31 min
May 27, 4:00 PM MDTTornado WarningBOUWeld15 min
May 27, 4:04 PM MDTSevere Thunderstorm WarningCYSGoshen41 min
May 27, 4:11 PM MDTSevere Thunderstorm WarningCYSLaramie49 min
May 27, 4:28 PM MDTTornado WarningBOULogan, Sedgwick47 min
May 27, 4:47 PM MDTSevere Thunderstorm WarningCYSGoshen28 min
May 27, 4:49 PM MDTTornado WarningBOUAdams, Weld26 min
May 27, 4:55 PM MDTTornado WarningBOULogan, Phillips, Sedgwick35 min
May 27, 4:58 PM MDTSevere Thunderstorm WarningBOUWeld47 min
May 27, 5:26 PM MDTTornado WarningBOUSedgwick32 min
May 27, 5:40 PM MDTSevere Thunderstorm WarningBOUPhillips50 min
May 27, 5:52 PM MDTFlash Flood WarningBOULogan83 min
May 27, 6:01 PM MDTTornado WarningBOUPhillips44 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, 6.9 hours before the alert went out and 111 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, Denver, CO at 12:00Z on 2019-05-27Temperature 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, Denver, CO at 12:00Z on 2019-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
1644 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
12 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
May 26, 7:50 PM MDTMesoscale DiscussionSPCProwers55 min
May 27, 12:36 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Logan, Morgan, Phillips, Sedgwick and 3 more2 hr
May 27, 2:43 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Denver, Logan, Morgan, Washington and 1 more2 hr
May 27, 4:27 PM MDTSevere Thunderstorm WatchSPCYuma9 hr
May 26, 7:53 PM MDTMesoscale DiscussionSPCAdams, Clay, Fillmore, Gage, Hall, Hamilton and 10 more2 hr
May 27, 12:54 AM MDTMesoscale DiscussionSPCGage, Jefferson, Johnson, Nemaha, Pawnee, Richardson111 min
May 27, 1:41 AM MDTSevere Thunderstorm WatchSPCCass, Gage, Jefferson, Johnson, Nemaha, Otoe and 2 more4 hr
May 27, 3:39 PM MDTMesoscale DiscussionSPCAdams, Arthur, Buffalo, Chase, Custer, Dawson and 19 more2 hr

Nearby

Tornado Watches in Colorado, 2019Tornado Watches in Nebraska, 2019Tornado Watches in Wyoming, 2019Every tornado watch in 2019

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.