Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 467, NWS Denver/Boulder, CO

September 14, 2023Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Sep 14, 2023, 6:00 PM MDT for Arapahoe 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 counties it named.

The facts

Issued
Sep 14, 2023, 6:00 PM MDT (00:00 UTC)
Expired
Sep 14, 2023, 6:26 PM MDT
In force
26 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

County Arapahoe County, CO

The radar

The Denver radar (KFTG), 23 km from the middle of the area, began a volume at 00:01 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.

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 Sep 14, 5:45 PM MDT, 15 minutes earlier.

Area forecast discussion, Sep 14, 5:45 PM MDT, 15 minutes before
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Hazardous weather outlook, Sep 14, 10:01 AM MDT, 7 hours 59 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1001 AM MDT Thu Sep 14 2023

COZ030>051-151615-
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-
1001 AM MDT Thu Sep 14 2023

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

.DAY ONE...Today and Tonight

Showers and storms will continue to form this morning and early
this afternoon across the higher terrain. This activity will
spread east onto the plains by the late afternoon. From the late
afternoon through much of tonight, there will be widespread
coverage of showers and storms. Some of these storms may produce
heavy rainfall with up to 2 inches of rain possible. There is an
elevated threat for flash flooding in the Cameron Peak burn area.
The heavy rain could cause minor flooding of roads and low lying
areas across Denver and the rest of the I-25 corridor and plains.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Showers will gradually decrease on Friday. An isolated storm or
two will still be possible in the afternoon over the mountains
with brief heavy rain. The threat of any flooding in recent burn
areas will be limited.

Generally dry and warmer weather will then prevail Saturday
through early next week.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Special weather statement, Sep 14, 2:37 PM MDT, 3 hours 23 minutes before
Special Weather Statement
National Weather Service Denver CO
237 PM MDT Thu Sep 14 2023

COZ050-051-142115-
Phillips County CO-Sedgwick County CO-
237 PM MDT Thu Sep 14 2023

...A strong thunderstorms will impact portions of northwestern
Phillips and western Sedgwick Counties through 315 PM MDT...

At 236 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms from I-76 southward to near Haxtun, moving slowly
eastward.

HAZARD...Penny size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
Holyoke, Haxtun, Paoli, Fairfield, Highland Center, and Marks Butte.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4052 10265 4086 10265 4097 10234 4056 10223
TIME...MOT...LOC 2036Z 249DEG 12KT 4071 10249

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...<30 MPH

RODRIGUEZ
Special weather statement, Sep 14, 3:20 PM MDT, 2 hours 40 minutes before
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Local storm report, Sep 14, 3:43 PM MDT, 2 hours 17 minutes before
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Local storm report, Sep 14, 4:08 PM MDT, 1 hour 52 minutes before
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Special weather statement, Sep 14, 4:24 PM MDT, 1 hour 36 minutes before
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Local storm report, Sep 14, 5:07 PM MDT, 53 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Sep 14, 6:15 PM MDTAreal Flood AdvisoryBOUDouglas, Elbert2 hr
Sep 15, 5:39 PM MDTAreal Flood AdvisoryBOUGrand111 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2023Every severe thunderstorm warning in 2023

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.