Alert archive / Colorado / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 265, NWS Denver/Boulder, CO

August 19, 2024Logan County, Morgan County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 19, 2024, 5:58 PM MDT for Logan County, Morgan County, Colorado. It was in force for 32 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 19, 2024, 5:58 PM MDT (23:58 UTC)
Expired
Aug 19, 2024, 6:30 PM MDT
In force
32 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

Counties Logan County, CO, Morgan County, CO

The radar

The Denver radar (KFTG), 121 km from the middle of the area, began a volume at 00:02 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 19, 1:43 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 12.0 hours before the alert went out and 251 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 2024-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2024-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1300 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

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 Aug 19, 5:54 PM MDT, 4 minutes earlier.

Area forecast discussion, Aug 19, 5:54 PM MDT, 4 minutes before
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Hazardous weather outlook, Aug 19, 10:23 AM MDT, 7 hours 35 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1023 AM MDT Mon Aug 19 2024

COZ030>051-201630-
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-
1023 AM MDT Mon Aug 19 2024

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

.DAY ONE...Today and Tonight

Thunderstorms are likely this afternoon and early evening. Some
storms may be severe over the plains with large hail greater than
an inch and strong winds to 60 mph.

Heavy rainfall is possible which could lead to flash flooding,
especially in flood prone alpine burn areas.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Warm weather will continue through the week with highs in the low
to mid 90s most afternoons. Drier weather is expected for
Tuesday with isolated thunderstorms. Moisture increases again for
Wednesday through Friday with at least scattered thunderstorms
expected each afternoon and evening. A drier trend is expected
again for the weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight, but
reports of heavy rain and severe weather will be appreciated.

Meier/Gimmestad

In the hours before

Local storm report, Aug 19, 3:19 PM MDT, 2 hours 39 minutes before
Preliminary Local Storm Report...Summary
National Weather Service Denver CO
319 PM MDT Mon Aug 19 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0303 PM     Tstm Wnd Dmg     9 SSE Shamrock          39.78N 103.74W
08/19/2024                   Adams              CO   Trained Spotter

            Large tree limb, 6 inches in diameter,
            snapped. Marble hail and torrential rain.

0255 PM     Tornado          10 NNE Deer Trail       39.75N 103.99W
08/19/2024                   Adams              CO   Trained Spotter

            Location approximate.

0221 PM     Hail             3 N Matheson            39.22N 103.98W
08/19/2024  M1.50 Inch       Elbert             CO   Trained Spotter

            Report from mPING: Ping Pong Ball (1.50
            in.).

0204 PM     Tornado          1 W Shamrock            39.89N 103.83W
08/19/2024                   Adams              CO   Storm Chaser

            Landspout. Estimated to be 4-5 miles
            south/southeast of Prospect Rd and CR 152 in
            eastern Adams County.

&&
Local storm report, Aug 19, 3:40 PM MDT, 2 hours 18 minutes before
Preliminary Local Storm Report
National Weather Service Denver CO
340 PM MDT Mon Aug 19 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0335 PM     Flash Flood      7 NNW Simla             39.23N 104.12W
08/19/2024                   Elbert             CO   Dept of Highways

            Flash flooding. County Roads department has
            closded CR 117 from Highway 86 south to CR
            90. Reed Springs Creek is over the road.

&&
Local storm report, Aug 19, 4:05 PM MDT, 1 hour 53 minutes before
Preliminary Local Storm Report...Summary
National Weather Service Denver CO
405 PM MDT Mon Aug 19 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0339 PM     Hail             8 S Matheson            39.06N 103.95W
08/19/2024  M0.75 Inch       Elbert             CO   Public

            Report from mPING: Dime (0.75 in.).

0335 PM     Flash Flood      7 NNW Simla             39.23N 104.12W
08/19/2024                   Elbert             CO   Dept of Highways

            Flash flooding. County Roads department has
            closded CR 117 from Highway 86 south to CR
            90. Reed Springs Creek is over the road.

0303 PM     Tstm Wnd Dmg     9 SSE Shamrock          39.78N 103.74W
08/19/2024                   Adams              CO   Trained Spotter

            Large tree limb, 6 inches in diameter,
            snapped. Marble hail and torrential rain.

0255 PM     Tornado          10 NNE Deer Trail       39.75N 103.99W
08/19/2024                   Adams              CO   Trained Spotter

            Location approximate.

0221 PM     Hail             3 N Matheson            39.22N 103.98W
08/19/2024  M1.50 Inch       Elbert             CO   Trained Spotter

            Report from mPING: Ping Pong Ball (1.50
            in.).

0204 PM     Tornado          1 W Shamrock            39.89N 103.83W
08/19/2024                   Adams              CO   Storm Chaser

            Landspout. Estimated to be 4-5 miles
            south/southeast of Prospect Rd and CR 152 in
            eastern Adams County.

&&
Local storm report, Aug 19, 4:46 PM MDT, 1 hour 12 minutes before
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Local storm report, Aug 19, 5:37 PM MDT, 21 minutes before
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Local storm report, Aug 19, 5:43 PM MDT, 15 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 6:26 PM MDTSpecial Weather StatementBOUDenver34 min
Aug 18, 6:51 PM MDTSpecial Weather StatementBOULincoln24 min
Aug 19, 12:17 PM MDTSpecial Weather StatementBOUElbert43 min
Aug 19, 12:35 PM MDTSpecial Weather StatementBOUElbert25 min
Aug 19, 1:21 PM MDTSpecial Weather StatementBOUElbert39 min
Aug 19, 1:36 PM MDTFlash Flood WarningBOUElbert3 hr
Aug 19, 1:47 PM MDTSevere Thunderstorm WarningBOUElbert28 min
Aug 19, 1:54 PM MDTSpecial Weather StatementBOUMorgan36 min
Aug 19, 2:13 PM MDTSevere Thunderstorm WarningBOUElbert47 min
Aug 19, 2:15 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan, Washington45 min
Aug 19, 2:56 PM MDTTornado WarningBOUElbert34 min
Aug 19, 2:57 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Washington48 min
Aug 19, 3:36 PM MDTAreal Flood AdvisoryBOUAdams, Arapahoe, Morgan, Washington3 hr
Aug 19, 3:41 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUAdams, Arapahoe, Washington49 min
Aug 19, 3:53 PM MDTFlash Flood WarningBOUAdams, Arapahoe, Washington3 hr
Aug 19, 4:20 PM MDTFlash Flood Warning Considerable damage threatBOUElbert3 hr
Aug 19, 4:24 PM MDTSevere Thunderstorm WarningBOULogan, Weld51 min
Aug 19, 4:25 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln50 min
Aug 19, 4:30 PM MDTSevere Thunderstorm WarningBOUWeld45 min
Aug 19, 4:54 PM MDTAreal Flood AdvisoryBOUBoulder2 hr
Aug 19, 5:10 PM MDTSevere Thunderstorm WarningBOULogan, Weld35 min
Aug 19, 5:32 PM MDTAreal Flood AdvisoryBOULogan, Weld118 min
Aug 19, 5:36 PM MDTSevere Thunderstorm WarningBOULincoln39 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.