Alert archive / Colorado / Flash Flood Warnings in 2021

Flash Flood Warning 33, NWS Goodland, KS

August 12, 2021Kit Carson County, Colorado

NWS Goodland, KS issued this flash flood warning at Aug 12, 2021, 7:28 PM MDT for Kit Carson County, Colorado. It was in force for 3 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 12, 2021, 7:28 PM MDT (01:28 UTC)
Expired
Aug 12, 2021, 10:30 PM MDT
In force
3 hr
Issued by
NWS Goodland, KS
Area
Storm-based polygon
Flood severity
None

County Kit Carson County, CO

The radar

The Goodland radar (KGLD), 91 km from the middle of the area, began a volume at 01:29 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 was reported inside it

TimeReportWhereRemark
Aug 12, 8:40 PM MDTHEAVY RAIN 6.05Vona, CORAINFALL STARTED AROUND 530PM MT, JUST SPRINKLING NOW.
Aug 12, 8:41 PM MDTFLASH FLOOD1 Wsw Vona, COREPORTS OF BASEMENTS FLOODING, SOME SIDEWALKS DOWNTOWN ARE NOT VISIBLE DUE TO THE STANDING WATER. 6 INCHES OF RAIN FELL IN 3 HOURS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 1.5 hours before the alert went out and 75 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, Denver, CO at 00:00Z on 2021-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 616 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2021-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
616 J/kg
Mixed-layer CIN
-65 J/kg
Mixed-layer LCL
2322 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

734 
WGUS53 KGLD 130128
FFWGLD
COC063-130430-
/O.NEW.KGLD.FF.W.0033.210813T0128Z-210813T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Goodland KS
728 PM MDT Thu Aug 12 2021

The National Weather Service in Goodland has issued a

* Flash Flood Warning for...
  Central Kit Carson County in east central Colorado...

* Until 1030 PM MDT.

* At 728 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Vona.

This includes the following highways...
	Interstate 70 in Colorado between mile markers 408 and 417.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3935 10283 3936 10265 3922 10264 3922 10282

FLASH FLOOD...RADAR INDICATED

$$

024
2 follow-up statements
865 
WGUS73 KGLD 130225
FFSGLD

Flash Flood Statement
National Weather Service Goodland KS
825 PM MDT Thu Aug 12 2021

COC063-130430-
/O.CON.KGLD.FF.W.0033.000000T0000Z-210813T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kit Carson CO-
825 PM MDT Thu Aug 12 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM MDT THIS 
EVENING FOR CENTRAL KIT CARSON COUNTY...

At 825 PM MDT, gauge reports indicated thunderstorms producing heavy 
rain across the warned area. Between 5 and 6 inches of rain have 
fallen. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Gauges reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Vona.

This includes the following highways...
	Interstate 70 in Colorado between mile markers 408 and 417.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3935 10283 3936 10265 3922 10264 3922 10282

FLASH FLOOD...GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

024
763 
WGUS73 KGLD 130426
FFSGLD

Flash Flood Statement
National Weather Service Goodland KS
1026 PM MDT Thu Aug 12 2021

COC063-130436-
/O.EXP.KGLD.FF.W.0033.000000T0000Z-210813T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kit Carson CO-
1026 PM MDT Thu Aug 12 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1030 PM MDT THIS EVENING FOR 
CENTRAL KIT CARSON COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3935 10283 3936 10265 3922 10264 3922 10282

$$

024

The office that day

Everything else NWS Goodland, KS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 12, 7:08 PM MDTSpecial Weather StatementGLDKit Carson37 min
Aug 12, 7:16 PM MDTSevere Thunderstorm WarningGLDKit Carson29 min
Aug 12, 7:45 PM MDTSevere Thunderstorm WarningGLDKit Carson45 min
Aug 12, 7:52 PM MDTSevere Thunderstorm WarningGLDKit Carson29 min

Nearby

Flash Flood Warnings in Colorado, 2021Every flash flood warning in 2021

Sources

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