Alert archive / Colorado / Flash Flood Warnings in 2021

Flash Flood Warning 37, NWS Goodland, KS

August 19, 2021Yuma County, Colorado

NWS Goodland, KS issued this flash flood warning at Aug 19, 2021, 7:50 PM MDT for Yuma County, Colorado. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 19, 2021, 7:50 PM MDT (01:50 UTC)
Expired
Aug 20, 2021, 12:28 AM MDT
In force
5 hr
Issued by
NWS Goodland, KS
Area
Storm-based polygon
Flood severity
None

County Yuma County, CO

The radar

The Goodland radar (KGLD), 117 km from the middle of the area, began a volume at 01:51 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

Denver, CO (KDNR), launched 00:00Z, 1.8 hours before the alert went out and 99 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 2021-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 56 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 2021-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 square meters per square second.19395878Sfc1 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
56 J/kg
Mixed-layer CIN
-210 J/kg
Mixed-layer LCL
1497 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
222 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

384 
WGUS53 KGLD 200150
FFWGLD
COC125-200645-
/O.NEW.KGLD.FF.W.0037.210820T0150Z-210820T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Goodland KS
750 PM MDT Thu Aug 19 2021

The National Weather Service in Goodland has issued a

* Flash Flood Warning for...
  Northeastern Yuma County in northeastern Colorado...

* Until 1245 AM MDT.

* At 750 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 5 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...
  Wauneta and Alvin.

Very heavy rain has fallen across eastern Phillips county. Some of 
this runoff may drain into northeast Yuma county, causing a rapid 
rise in water levels

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4029 10205 4021 10249 4044 10251 4044 10205

FLASH FLOOD...RADAR INDICATED

$$

JRM
3 follow-up statements
438 
WGUS73 KGLD 200342
FFSGLD

Flash Flood Statement
National Weather Service Goodland KS
942 PM MDT Thu Aug 19 2021

COC125-200645-
/O.CON.KGLD.FF.W.0037.000000T0000Z-210820T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma CO-
942 PM MDT Thu Aug 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM MDT FRIDAY 
FOR NORTHEASTERN YUMA COUNTY...

At 942 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 6 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...
  Wauneta and Alvin.

Very heavy rain has fallen across eastern Phillips county. Some of 
this runoff may drain into northeast Yuma county, causing a rapid 
rise in water levels. Be especially cautious along the Frenchman and 
Patent creek in northeast Yuma county.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4029 10205 4021 10249 4044 10251 4044 10205

FLASH FLOOD...RADAR INDICATED

$$

JRM
691 
WGUS73 KGLD 200419
FFSGLD

Flash Flood Statement
National Weather Service Goodland KS
1019 PM MDT Thu Aug 19 2021

COC125-200645-
/O.CON.KGLD.FF.W.0037.000000T0000Z-210820T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma CO-
1019 PM MDT Thu Aug 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM MDT FRIDAY 
FOR NORTHEASTERN YUMA COUNTY...

At 1019 PM MDT, Doppler radar indicated thunderstorms producing 
heavy rain across the warned area. Between 1 and 3 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...
  Wauneta and Alvin.

This includes the following highways...
	Highway 385 between mile markers 257 and 269.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 4029 10205 4021 10249 4044 10251 4044 10205

FLASH FLOOD...RADAR INDICATED

$$

Vincent
444 
WGUS73 KGLD 200628
FFSGLD

Flash Flood Statement
National Weather Service Goodland KS
1228 AM MDT Fri Aug 20 2021

COC125-200638-
/O.CAN.KGLD.FF.W.0037.000000T0000Z-210820T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yuma CO-
1228 AM MDT Fri Aug 20 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN YUMA COUNTY...

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

LAT...LON 4029 10205 4021 10249 4044 10251 4044 10205

$$

MRC/JN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 6:28 PM MDTSpecial Weather StatementGLDPhillips47 min
Aug 19, 6:31 PM MDTSpecial Weather StatementGLDYuma44 min
Aug 19, 6:46 PM MDTSevere Thunderstorm WarningGLDYuma44 min
Aug 19, 7:17 PM MDTSpecial Weather StatementGLDPhillips28 min
Aug 19, 7:31 PM MDTSevere Thunderstorm WarningGLDYuma59 min
Aug 19, 7:36 PM MDTTornado WarningGLDYuma24 min
Aug 19, 8:08 PM MDTTornado WarningGLDYuma22 min
Aug 19, 8:44 PM MDTSevere Thunderstorm WarningGLDYuma31 min
Aug 19, 9:14 PM MDTSevere Thunderstorm WarningGLDYuma46 min
Aug 19, 9:49 PM MDTSpecial Weather StatementGLDYuma26 min
Aug 19, 10:48 PM MDTSpecial Weather StatementGLDPhillips42 min
Aug 19, 10:51 PM MDTSpecial Weather StatementGLDYuma39 min
Aug 20, 12:31 AM MDTAreal Flood WarningGLDYuma6 hr
Aug 20, 5:40 AM MDTSpecial Weather StatementGLDPhillips35 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.