Alert archive / Colorado / Special Weather Statements in 2021
Special Weather Statement, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this special weather statement at May 21, 2021, 10:57 PM MDT for Phillips County, Sedgwick County, Colorado. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- May 21, 2021, 10:57 PM MDT (04:57 UTC)
- Expired
- May 21, 2021, 11:45 PM MDT
- In force
- 48 min
- Issued by
- NWS Denver/Boulder, CO
Counties Phillips County, CO, Sedgwick County, CO
The radar
The Goodland radar (KGLD), 155 km from the middle of the area, began a volume at 05:01 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.
The nearest sounding before it
Denver, CO (KDNR), launched 00:00Z, 5.0 hours before the alert went out and 115 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3010 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 163 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>What forecasters said that day
The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before this special weather statement went out at May 21, 8:54 PM MDT, 2 hours 3 minutes earlier.
Area forecast discussion, May 21, 8:54 PM MDT, 2 hours 3 minutes before
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</html>Hazardous weather outlook, May 21, 11:24 AM MDT, 11 hours 33 minutes before
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1124 AM MDT Fri May 21 2021 COZ030>051-221730- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1124 AM MDT Fri May 21 2021 ...WINDY THIS AFTERNOON WITH SEVERE STORMS NEAR THE EASTERN BORDER... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...This Afternoon and Tonight Strong winds will develop this afternoon on the plains and over the mountains south of Interstate 70. Gusts of 40 to 55 mph will be common. The strongest winds will likely be south and southeast of Denver. Thunderstorms will develop near the eastern border and move from south to north through the evening. Some of these storms could be severe with large hail up to 2 inches in diameter and wind gusts to 75 mph possible. The main threat is east of a line from Sterling to Limon between 5 and 9 PM. Some weaker showers and thunderstorms will develop over the mountains in the late afternoon and early evening. Brief wind gusts to 60 mph are possible with a few of these storms. The severe threat will end by late evening, but a few weaker showers or storms may linger overnight. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Scattered afternoon and evening thunderstorms are expected Saturday. Some of these storms may be severe across the plains, with the greatest threat east and southeast of Denver. Large hail and damaging winds are the primary threats, though an isolated tornado is also possible. Brief heavy rain is possible, though the fast storm motion will limit the flood threat. Severe thunderstorms can again be expected on Sunday, but this time more focused over the eastern plains, roughly along and east of a Sterling to Akron line. Those storms will be developing along a well pronounced dryline which is expected to sweep east across the area during the afternoon. Behind that, including the I-25 Corridor and mountains, mostly dry conditions will prevail. Monday through Thursday of next week will be drier with near normal temperatures, though afternoon and evening storms will begin increasing Wednesday and Thursday. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated today or tonight. However any severe weather reports of large hail or damaging winds would be appreciated. Gimmestad/Barjenbruch
In the hours before
Special weather statement, May 21, 5:30 PM MDT, 5 hours 27 minutes before
Special Weather Statement National Weather Service Denver CO 530 PM MDT Fri May 21 2021 COZ047-220000- Southeast Elbert County Below 6000 Feet/South Lincoln County CO- 530 PM MDT Fri May 21 2021 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN LINCOLN COUNTY UNTIL 600 PM MDT... At 530 PM MDT, Doppler radar was tracking a strong thunderstorm near Wild Horse Point, or 40 miles north of North La Junta, moving north at 65 mph. Nickel size hail and wind gusts of 50 to 55 mph will be possible with this storm. Locations impacted include... Karval, Boyero and Wild Horse Point. LAT...LON 3903 10366 3901 10316 3852 10330 3852 10358 TIME...MOT...LOC 2330Z 183DEG 57KT 3858 10344 DIRENZO
Local storm report, May 21, 7:18 PM MDT, 3 hours 39 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
718 PM MDT FRI MAY 21 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0645 PM TSTM WND DMG 1 S SNYDER 40.30N 103.58W
05/21/2021 MORGAN CO TRAINED SPOTTER
POWER LINES DOWN IN THE BRUSH AND HILLROSE
AREA.
&&Special weather statement, May 21, 7:18 PM MDT, 3 hours 39 minutes before
Special Weather Statement National Weather Service Denver CO 718 PM MDT Fri May 21 2021 COZ048-049-220145- Washington County CO-Logan County CO- 718 PM MDT Fri May 21 2021 ...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL WASHINGTON AND SOUTHWESTERN LOGAN COUNTIES UNTIL 745 PM MDT... At 717 PM MDT, trained weather spotters reported a strong thunderstorm 4 miles south of Prewitt Reservoir, or 17 miles northwest of Akron, moving north at 40 mph. Wind gusts of 50 to 55 mph will be possible with this storm. Locations impacted include... Sterling, Akron, Merino, Prewitt Reservoir, Atwood, Logan Corners and Midway. PRECAUTIONARY/PREPAREDNESS ACTIONS... Prepare for sudden gusty winds. Secure loose objects and move to a safe shelter inside a building or vehicle. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && A Severe Thunderstorm Watch remains in effect until 1000 PM MDT for northeastern Colorado. LAT...LON 4007 10314 4005 10347 4065 10346 4067 10315 TIME...MOT...LOC 0117Z 196DEG 49KT 4037 10339 DIRENZO
Local storm report, May 21, 10:08 PM MDT, 49 minutes before
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</html>Special weather statement, May 21, 10:57 PM MDT, 0 minutes before
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</html>The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 7:18 PM MDT | Special Weather Statement | BOU | Morgan | 27 min |
| May 22, 1:11 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Logan, Morgan, Washington | 49 min |
| May 22, 1:28 PM MDT | Tornado Warning | BOU | Morgan | 17 min |
| May 22, 1:45 PM MDT | Tornado Warning | BOU | Morgan | 15 min |
| May 22, 1:54 PM MDT | Tornado Warning | BOU | Morgan, Washington | 36 min |
| May 22, 1:56 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 28 min |
| May 22, 1:58 PM MDT | Severe Thunderstorm Warning | BOU | Logan, Morgan, Washington | 33 min |
| May 22, 2:05 PM MDT | Tornado Warning | BOU | Adams, Arapahoe | 25 min |
| May 22, 2:18 PM MDT | Special Weather Statement | BOU | Adams | 42 min |
| May 22, 2:43 PM MDT | Tornado Warning | BOU | Logan | 17 min |
| May 22, 2:46 PM MDT | Severe Thunderstorm Warning | BOU | Phillips, Sedgwick | 44 min |
| May 22, 2:57 PM MDT | Severe Thunderstorm Warning | BOU | Logan, Sedgwick | 48 min |
| May 22, 3:01 PM MDT | Tornado Warning | BOU | Logan | 29 min |
| May 22, 3:16 PM MDT | Tornado Warning | BOU | Lincoln | 29 min |
| May 22, 3:25 PM MDT | Severe Thunderstorm Warning | BOU | Weld | 35 min |
| May 22, 3:48 PM MDT | Tornado Warning | BOU | Elbert, Lincoln | 27 min |
| May 22, 3:53 PM MDT | Severe Thunderstorm Warning | BOU | Morgan, Weld | 26 min |
| May 22, 4:13 PM MDT | Tornado Warning | BOU | Elbert, Lincoln | 32 min |
| May 22, 4:42 PM MDT | Tornado Warning | BOU | Elbert, Lincoln | 33 min |
| May 22, 5:16 PM MDT | Tornado Warning | BOU | Elbert, Lincoln | 29 min |
| May 22, 5:27 PM MDT | Severe Thunderstorm Warning | BOU | Elbert, Lincoln | 33 min |
Nearby
Special Weather Statements in Colorado, 2021Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.