Alert archive / Colorado / Special Weather Statements in 2018
Special Weather Statement, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this special weather statement at Jun 15, 2018, 2:49 PM MDT for Weld County, Colorado. It was in force for 26 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
- Jun 15, 2018, 2:49 PM MDT (20:49 UTC)
- Expired
- Jun 15, 2018, 3:15 PM MDT
- In force
- 26 min
- Issued by
- NWS Denver/Boulder, CO
County Weld County, CO
The radar
The Cheyenne radar (KCYS), 44 km from the middle of the area, began a volume at 20:52 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 (KDEN), launched 12:00Z, 8.8 hours before the alert went out and 151 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
- 21 J/kg
- Mixed-layer CIN
- -288 J/kg
- Mixed-layer LCL
- 3355 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 3 m²/s²
- 0-3 km storm-relative helicity
- -35 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 Jun 15, 12:40 PM MDT, 2 hours 9 minutes earlier.
Area forecast discussion, Jun 15, 12:40 PM MDT, 2 hours 9 minutes before
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</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
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</html>Hazardous weather outlook, Jun 15, 11:27 AM MDT, 3 hours 22 minutes before
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1127 AM MDT Fri Jun 15 2018 COZ030>051-161730- 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- 1127 AM MDT Fri Jun 15 2018 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Expect isolated to scattered coverage of afternoon and evening showers and thunderstorms over the mountains and plains. The main threat with the showers will again be gusty winds up to 45 mph. Slightly cooler temperatures can be expected following the passage of a weak cold front earlier this morning, along with higher low level moisture. This may lead to stronger and possibly a severe storm over the far northeast plains with damaging winds to 60 mph and hail up to one inch in diameter. The thunderstorms will diminish by later this evening. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Shower and thunderstorm coverage will increase this weekend and remain elevated through most of next week. The main threat from storms this weekend will be heavy rainfall, which could result in localized flooding. Burn scars will be particularly prone, although urban or poor drainage areas may also see some flooding should heavy rainfall develop. Moist upslope flow behind a cold front will expand the risk of heavy rainfall into the I-25 Corridor and adjacent plains Sunday afternoon and evening. One or two storms may also be severe with large hail the main threat. The unsettled weather and potential for locally heavy rainfall will remain in the forecast through the mid part of next week. A couple severe storms will again be possible Tuesday and Wednesday afternoon and evening. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today.
In the hours before
Special weather statement, Jun 15, 2:40 PM MDT, 9 minutes before
Special Weather Statement
National Weather Service Denver CO
240 PM MDT FRI JUN 15 2018
COZ040-041-043-152130-
Elbert/Central and East Douglas Counties Above 6000 Feet CO-
Central and South Weld County CO-
North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe
Counties/East Broomfield County CO-
240 PM MDT FRI JUN 15 2018
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN DOUGLAS...SOUTH
CENTRAL WELD...WESTERN ARAPAHOE...EASTERN DENVER AND WESTERN ADAMS
COUNTIES UNTIL 330 PM MDT...
At 238 PM MDT, Doppler radar was tracking scattered thunderstorms
along a line extending from near Keenesburg to 3 miles southeast of
Roxborough Park, or along a line extending from 24 miles southeast
of Greeley to 23 miles south of Denver. Movement was northeast at 20
mph.
Brief wind gusts of 50 to 55 mph will be possible with these storms.
Locations impacted include...
Eastern Denver, Aurora, Centennial, eastern Highlands Ranch, northern
Castle Rock, northeastern Commerce City, Parker, Brighton, Greenwood
Village, Lone Tree, Denver International Airport, Lochbuie, Hudson,
Keenesburg, Surrey Ridge, Arapahoe Park, Buckley AFB, Beverly Hills,
Watkins and Prospect Valley.
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 these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3941 10495 3944 10500 4013 10469 4012 10438
4000 10445 4000 10451 3989 10450 3939 10477
3937 10496
TIME...MOT...LOC 2038Z 236DEG 16KT 4010 10455 3940 10504
RPKSpecial weather statement, Jun 15, 2:49 PM MDT, 0 minutes before
Special Weather Statement
National Weather Service Denver CO
249 PM MDT FRI JUN 15 2018
COZ038-152115-
Larimer County Below 6000 Feet/Northwest Weld County CO-
249 PM MDT FRI JUN 15 2018
...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN WELD COUNTY UNTIL
315 PM MDT...
At 249 PM MDT, Doppler radar was tracking a strong thunderstorm 5
miles southeast of Rockport, or 20 miles south of Cheyenne, moving
northeast at 30 mph.
Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.
Locations impacted include...
Rockport.
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.
&&
LAT...LON 4082 10431 4079 10435 4078 10437 4070 10475
4100 10487 4100 10438
TIME...MOT...LOC 2049Z 240DEG 25KT 4086 10470
RPKThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 15, 12:35 PM MDT | Red Flag Warning | BOU | Grand, Jackson, Summit | 7 hr |
| Jun 15, 2:40 PM MDT | Special Weather Statement | BOU | Denver | 50 min |
| Jun 15, 2:46 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 29 min |
| Jun 15, 2:54 PM MDT | Severe Thunderstorm Warning | BOU | Weld | 36 min |
| Jun 15, 3:54 PM MDT | Special Weather Statement | BOU | Lincoln | 36 min |
| Jun 15, 4:09 PM MDT | Special Weather Statement | BOU | Adams | 36 min |
| Jun 15, 4:18 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 27 min |
| Jun 15, 4:52 PM MDT | Special Weather Statement | BOU | Washington | 23 min |
Nearby
Special Weather Statements in Colorado, 2018Every special weather statement in 2018
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.