Alert archive / Colorado / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 230, NWS Denver/Boulder, CO

August 11, 2024Adams County, Arapahoe County, Denver County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 11, 2024, 6:06 PM MDT for Adams County, Arapahoe County, Denver County, Colorado. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 11, 2024, 6:06 PM MDT (00:06 UTC)
Expired
Aug 11, 2024, 6:30 PM MDT
In force
24 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Adams County, CO, Arapahoe County, CO, Denver County, CO

The radar

The Denver radar (KFTG), 4 km from the middle of the area, began a volume at 00:07 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 forecasters said that day

The local office's own words before this severe thunderstorm warning 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 severe thunderstorm warning went out at Aug 11, 5:38 PM MDT, 28 minutes earlier.

Area forecast discussion, Aug 11, 5:38 PM MDT, 28 minutes before
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Hazardous weather outlook, Aug 11, 10:59 AM MDT, 7 hours 7 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1059 AM MDT Sun Aug 11 2024

COZ030>051-121700-
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-
1059 AM MDT Sun Aug 11 2024

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

Scattered thunderstorms are expected to redevelop over the
mountains by early afternoon and then spread and develop eastward
across the plains through the late afternoon hours. A couple
storms will likely become severe, mainly along and east of a
Sterling to Akron to Limon line where more instability exists. The
main threat is damaging wind gusts to around 60 mph, but large
hail is also possible.

The recent burn scars will see a limited threat of flash flooding,
as storms will be moving along and intensity of storms in/near the
mountains is expected to be a little less than yesterday.

Storms will diminish from northwest to southeast across the area
this evening.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Scattered to numerous showers and storms are expected to start the
week, most numerous over the high country and Palmer Divide.
Locally heavy rainfall is possible with the stronger storms that
could elevate the flash flood threat for sensitive areas like our
burn scars. A couple of storms could become severe Monday and
Monday evening with possibly a higher threat on Tuesday.

There will be a gradual warming and drying trend Wednesday
through Friday, with thunderstorm activity returning to a more
typical summer convective pattern as the week persists.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight. However,
any reports of heavy rainfall, strong wind gusts, or hail will be
appreciated.

In the hours before

Special weather statement, Aug 11, 2:21 PM MDT, 3 hours 45 minutes before
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Special weather statement, Aug 11, 2:27 PM MDT, 3 hours 39 minutes before
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Local storm report, Aug 11, 3:20 PM MDT, 2 hours 46 minutes before
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Special weather statement, Aug 11, 5:15 PM MDT, 51 minutes before
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Special weather statement, Aug 11, 5:56 PM MDT, 10 minutes before
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Special weather statement, Aug 11, 5:59 PM MDT, 7 minutes before
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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 8:23 PM MDTSpecial Weather StatementBOUDenver37 min
Aug 12, 1:20 AM MDTDense Fog AdvisoryBOULogan, Morgan, Phillips, Sedgwick, Washington, Weld8 hr
Aug 12, 9:50 AM MDTFlood WatchBOUAdams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver and 8 more14 hr
Aug 12, 12:20 PM MDTAreal Flood AdvisoryBOULarimer3 hr
Aug 12, 1:40 PM MDTAreal Flood AdvisoryBOULarimer3 hr
Aug 12, 1:55 PM MDTFlash Flood Warning Considerable damage threatBOULarimer3 hr
Aug 12, 2:52 PM MDTFlash Flood Warning Considerable damage threatBOULarimer2 hr
Aug 12, 3:51 PM MDTSpecial Weather StatementBOUArapahoe39 min
Aug 12, 4:20 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUWeld40 min
Aug 12, 4:44 PM MDTTornado WarningBOUWeld31 min
Aug 12, 5:08 PM MDTSpecial Weather StatementBOUElbert52 min
Aug 12, 5:09 PM MDTFlash Flood WarningBOUArapahoe, Elbert3 hr
Aug 12, 5:15 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUWeld45 min
Aug 12, 5:17 PM MDTAreal Flood AdvisoryBOUElbert14 min
Aug 12, 5:21 PM MDTSpecial Weather StatementBOUWeld39 min
Aug 12, 5:26 PM MDTTornado WarningBOUWeld34 min
Aug 12, 5:31 PM MDTFlash Flood WarningBOUElbert3 hr
Aug 12, 5:31 PM MDTSpecial Weather StatementBOUElbert44 min
Aug 12, 5:48 PM MDTTornado WarningBOUWeld27 min
Aug 12, 5:54 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUMorgan51 min
Aug 12, 5:57 PM MDTAreal Flood AdvisoryBOUElbert104 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2024Every severe thunderstorm warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.