Alert archive / Colorado / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 113, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 17, 2021, 8:10 PM MDT for Logan County, Morgan County, Washington County, Colorado. It was in force for 50 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 17, 2021, 8:10 PM MDT (02:10 UTC)
- Expired
- Jul 17, 2021, 9:00 PM MDT
- In force
- 50 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Logan County, CO, Morgan County, CO, Washington County, CO
The radar
The Denver radar (KFTG), 119 km from the middle of the area, began a volume at 02:11 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 17, 8:15 PM MDT | TSTM WND GST 60 | 2 Ene Brush, CO | SMALL TREE LIMBS SNAPPED. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Denver, CO (KDNR), launched 00:00Z, 2.2 hours before the alert went out and 57 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.
- Mixed-layer CAPE
- 55 J/kg
- Mixed-layer CIN
- -39 J/kg
- Mixed-layer LCL
- 3294 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- -14 m²/s²
- 0-3 km storm-relative helicity
- 4 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
126
WUUS55 KBOU 180210
SVRBOU
COC075-087-121-180300-
/O.NEW.KBOU.SV.W.0113.210718T0210Z-210718T0300Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
810 PM MDT Sat Jul 17 2021
The National Weather Service in Denver Colorado has issued a
* Severe Thunderstorm Warning for...
Eastern Morgan County in northeastern Colorado...
North central Washington County in northeastern Colorado...
Southwestern Logan County in northeastern Colorado...
* Until 900 PM MDT.
* At 810 PM MDT, severe thunderstorms were located along a line
extending from 4 miles southwest of Willard to 4 miles south of
Brush, or along a line extending from 19 miles southwest of
Sterling to 8 miles southeast of Fort Morgan, moving east at 20
mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees. Hail damage to
vehicles is expected.
* Locations impacted include...
Brush, Merino, Hillrose, Prewitt Reservoir, Atwood, Snyder, Midway
and Willard.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4057 10312 4002 10329 4014 10376 4057 10356
TIME...MOT...LOC 0210Z 280DEG 15KT 4050 10352 4020 10366
HAIL...1.00IN
WIND...60MPH
$$
HIRIS2 follow-up statements
351
WWUS55 KBOU 180238
SVSBOU
Severe Weather Statement
National Weather Service Denver CO
838 PM MDT Sat Jul 17 2021
COC075-087-121-180300-
/O.CON.KBOU.SV.W.0113.000000T0000Z-210718T0300Z/
Morgan CO-Washington CO-Logan CO-
838 PM MDT Sat Jul 17 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM MDT
FOR EASTERN MORGAN...NORTH CENTRAL WASHINGTON AND SOUTHWESTERN LOGAN
COUNTIES...
At 836 PM MDT, severe thunderstorms were located along a line
extending from near Merino to 7 miles southeast of Brush, or along a
line extending from 14 miles southwest of Sterling to 14 miles east
of Fort Morgan, moving east at 15 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees. Hail damage to
vehicles is expected.
Locations impacted include...
Brush, Merino, Hillrose, Prewitt Reservoir, Atwood, Snyder, Midway
and Willard.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4057 10312 4002 10329 4013 10372 4057 10352
TIME...MOT...LOC 0236Z 280DEG 15KT 4048 10339 4018 10353
HAIL...1.00IN
WIND...60MPH
$$
HIRIS766
WWUS55 KBOU 180250
SVSBOU
Severe Weather Statement
National Weather Service Denver CO
850 PM MDT Sat Jul 17 2021
COC075-087-121-180300-
/O.EXP.KBOU.SV.W.0113.000000T0000Z-210718T0300Z/
Morgan CO-Washington CO-Logan CO-
850 PM MDT Sat Jul 17 2021
...THE SEVERE THUNDERSTORM WARNING FOR EASTERN MORGAN...NORTH CENTRAL
WASHINGTON AND SOUTHWESTERN LOGAN COUNTIES WILL EXPIRE AT 900 PM
MDT...
The storms 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.
LAT...LON 4057 10312 4002 10329 4013 10372 4057 10352
TIME...MOT...LOC 0250Z 270DEG 15KT 4047 10333 4017 10347
$$
HIRISThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 6:01 PM MDT | Special Weather Statement | BOU | Denver | 29 min |
| Jul 17, 6:42 PM MDT | Special Weather Statement | BOU | Arapahoe | 33 min |
| Jul 17, 6:53 PM MDT | Special Weather Statement | BOU | Morgan | 22 min |
| Jul 17, 7:06 PM MDT | Special Weather Statement | BOU | Adams | 24 min |
| Jul 17, 7:11 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Morgan | 34 min |
| Jul 17, 7:37 PM MDT | Areal Flood Advisory | BOU | Adams, Morgan | 113 min |
| Jul 17, 7:44 PM MDT | Special Weather Statement | BOU | Morgan | 46 min |
| Jul 17, 8:55 PM MDT | Special Weather Statement | BOU | Logan | 50 min |
| Jul 17, 9:13 PM MDT | Special Weather Statement | BOU | Crowley | 47 min |
| Jul 17, 10:18 PM MDT | Special Weather Statement | BOU | Lincoln | 42 min |
| Jul 17, 10:38 PM MDT | Areal Flood Advisory | BOU | Elbert, Lincoln | 82 min |
Nearby
Severe Thunderstorm Warnings in Colorado, 2021Every 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.