Alert archive / Colorado / Flash Flood Warnings in 2012

Flash Flood Warning 13, NWS Grand Junction, CO

July 31, 2012Ouray County, San Miguel County, Colorado

NWS Grand Junction, CO issued this flash flood warning at Jul 31, 2012, 2:23 PM MDT for Ouray County, San Miguel County, Colorado. It was in force for 3 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
Jul 31, 2012, 2:23 PM MDT (20:23 UTC)
Expired
Jul 31, 2012, 5:30 PM MDT
In force
3 hr
Issued by
NWS Grand Junction, CO
Area
Storm-based polygon
Flood severity
None

Counties Ouray County, CO, San Miguel County, CO

The radar

The Grand Junction radar (KGJX), 120 km from the middle of the area, began a volume at 20:24 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

Grand Junction, CO (KGJT), launched 12:00Z, 8.4 hours before the alert went out and 135 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, Grand Junction, CO at 12:00Z on 2012-07-31Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Grand Junction, CO at 12:00Z on 2012-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1967 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

789 
WGUS55 KGJT 312023
FFWGJT
COC091-113-312330-
/O.NEW.KGJT.FF.W.0013.120731T2023Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
223 PM MDT TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN GRAND JUNCTION HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN SAN MIGUEL COUNTY IN WEST CENTRAL COLORADO...
  SOUTH CENTRAL OURAY COUNTY IN SOUTHWEST COLORADO...

* UNTIL 530 PM MDT

* AT 221 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RAINFALL RATES OF OVER AN INCH PER HOUR CAN           
  BE EXPECTED. 

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...     
  AREAS ALONG HIGHWAY 145 AND BETWEEN SAWPIT AND                     
  TELLURIDE...AND NEAR THE JUNCTION WITH HIGHWAY 62

LAW ENFORCEMENT OFFICIALS HAVE REPORTED SOME MUDSLIDE OCCURRING IN 
THIS AREA SO TRAVEL DELAYS CAN BE EXPECTED. DO NOT DRIVE OVER 
ROADWAYS COVERED IN WATER OR DEBRIS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

&&

LAT...LON 3810 10773 3785 10779 3790 10810 3813 10804

$$
15
2 follow-up statements
133 
WGUS75 KGJT 312122
FFSGJT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
322 PM MDT TUE JUL 31 2012

COC091-113-312330-
/O.CON.KGJT.FF.W.0013.000000T0000Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN MIGUEL CO-OURAY CO-
322 PM MDT TUE JUL 31 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTH CENTRAL OURAY AND
EASTERN SAN MIGUEL COUNTIES UNTIL 530 PM MDT...

AT 320 PM MDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED THAT MUD 
SLIDES HAVE CLOSED HIGHWAY 145 BETWEEN MILE MARKERS 70 AND 74 DUE TO 
HEAVY RAINFALL AND EXCESS RUNOFF.

SOME LOCATIONS THAT WILL CONTINUE EXPERIENCE FLOODING OVER THE NEXT 
FEW HOURS INCLUDE...SAWPIT AND TELLURIDE...ESPECIALLY ALONG HIGHWAY 
145 AND NEAR THE INTERSECTION OF HIGHWAY 145 AND 62.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS 
SAFELY.

&&

LAT...LON 3810 10773 3785 10779 3790 10810 3813 10804

$$
DP
211 
WGUS75 KGJT 312331
FFSGJT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
531 PM MDT TUE JUL 31 2012

COC091-113-312345-
/O.EXP.KGJT.FF.W.0013.000000T0000Z-120731T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN MIGUEL CO-OURAY CO-
531 PM MDT TUE JUL 31 2012

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTH CENTRAL OURAY
AND EASTERN SAN MIGUEL COUNTIES HAS BEEN ALLOWED TO EXPIRE...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE WERE BEGINNING TO RECEDE...ENDING 
THE FLOOD THREAT. HIGHWAY 145 HAS ALSO BEEN RE-OPENED IN BOTH 
DIRECTIONS AS OF 530 PM MDT. IF ADDITIONAL FLOODING HAS BEEN 
OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 3810 10773 3785 10779 3790 10810 3813 10804

$$
DP

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 31, 3:08 PM MDTSpecial Weather StatementGJTMontrose37 min
Jul 31, 3:34 PM MDTAreal Flood AdvisoryGJTGunnison, Montrose3 hr
Jul 31, 4:19 PM MDTSpecial Weather StatementGJTMontezuma41 min
Jul 31, 5:00 PM MDTAreal Flood AdvisoryGJTMontrose3 hr
Jul 31, 5:10 PM MDTSpecial Weather StatementGJTMesa50 min
Jul 31, 5:21 PM MDTFlash Flood WarningGJTMesa85 min
Jul 31, 5:25 PM MDTSpecial Weather StatementGJTMontezuma50 min

Nearby

Flash Flood Warnings in Colorado, 2012Every flash flood warning in 2012

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.