Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 81, NWS Denver/Boulder, CO

June 10, 2023Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 10, 2023, 4:00 PM MDT for Weld County, Colorado. It was in force for 30 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
Jun 10, 2023, 4:00 PM MDT (22:00 UTC)
Expired
Jun 10, 2023, 4:30 PM MDT
In force
30 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 75 km from the middle of the area, began a volume at 22:02 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.0 hours before the alert went out and 325 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.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2023-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2023-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -48 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
19 J/kg
Mixed-layer CIN
-216 J/kg
Mixed-layer LCL
1408 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-48 m²/s²
0-3 km storm-relative helicity
-48 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 Jun 10, 3:32 PM MDT, 28 minutes earlier.

Area forecast discussion, Jun 10, 3:32 PM MDT, 28 minutes before
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Hazardous weather outlook, Jun 10, 11:15 AM MDT, 4 hours 45 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1115 AM MDT Sat Jun 10 2023

COZ030>051-111715-
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-
1115 AM MDT Sat Jun 10 2023

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

.DAY ONE...Today and Tonight

Scattered showers and thunderstorms will develop across the higher
terrain and shift into the plains during the afternoon and evening.
Expect a few strong to marginally severe storms across the plains
with damaging winds and hail. The strongest storms will mainly
remain east of the urban corridor. The majority of the storms
today will produce brief heavy rain, small hail and wind gusts up
to 40 mph.

The flash flood potential in the mountains will remain limited
today with marginal moisture and instability. Cameron Peak burn
area may be a bit more prone to flooding due to stronger storms
in that area but decent storm motions should keep flash flood
potential still on the low side.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Showers and thunderstorms are likely over the mountains,
foothills and adjacent plains on Sunday evening. Heavy rains
could cause flash flooding and there will be an elevated threat of
flash flooding in the alpine burned areas. Both Monday and
Tuesday afternoons and evenings can expected likely showers and
thunderstorms with a flash flooding threat, especially in the
burned areas.

On Wednesday through Friday, scattered late day showers and
thunderstorms are expected. There will be more afternoon heating
so a few of the storms could be severe with large hail and
damaging winds.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed across the northeast plains this
afternoon, mainly sections east of the Interstate 25 corridor.
Reports of hail and damaging winds will be appreciated.

In the hours before

Special weather statement, Jun 10, 1:33 PM MDT, 2 hours 27 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jun 10, 11:49 AM MDTFlash Flood WarningBOULarimer114 min
Jun 10, 1:33 PM MDTSpecial Weather StatementBOUWeld27 min
Jun 10, 4:19 PM MDTSpecial Weather StatementBOUDouglas41 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.