Alert archive / Colorado / Flash Flood Warnings in 2012
Flash Flood Warning 27, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Sep 26, 2012, 6:48 PM MDT for Weld County, Colorado. It was in force for 2 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
- Sep 26, 2012, 6:48 PM MDT (00:48 UTC)
- Expired
- Sep 26, 2012, 9:06 PM MDT
- In force
- 2 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
County Weld County, CO
The radar
The Denver radar (KFTG), 33 km from the middle of the area, began a volume at 00:48 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, 0.8 hours before the alert went out and 126 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.
- Mixed-layer CAPE
- 294 J/kg
- Mixed-layer CIN
- -15 J/kg
- Mixed-layer LCL
- 1309 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 32 m²/s²
- 0-3 km storm-relative helicity
- 75 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
514 WGUS55 KBOU 270048 FFWBOU COC123-270345- /O.NEW.KBOU.FF.W.0027.120927T0048Z-120927T0345Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE DENVER CO 648 PM MDT WED SEP 26 2012 THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * FLASH FLOOD WARNING FOR... SOUTH CENTRAL WELD COUNTY IN NORTHEAST COLORADO * UNTIL 945 PM MDT * AT 646 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY RAIN FROM A THUNDERSTORM 3 MILES NORTH OF LOCHBUIE...OR 25 MILES SOUTH OF GREELEY. THIS STORM WAS MOVING NORTH AT 5 MPH. * LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LOCHBUIE AND HUDSON. THIS REPLACES THE SMALL STREAM FLOOD ADVISORY THAT WAS IN EFFECT FOR EXTREME SOUTH CENTRAL WELD COUNTY. DOPPLER RADAR AND WEATHER SPOTTERS ESTIMATE THAT 2 TO 3 OF RAIN OF RAIN HAS FALLEN FROM THIS STORM IN THE LAST ONE AND ONE HALF HOURS. PRECAUTIONARY/PREPAREDNESS ACTIONS... EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS AND STREAMS AND OTHER LOW LYING AREAS ARE SUBJECT TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY AS THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A FEW INCHES OF RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR VEHICLE. TURN AROUND...DO NOT DROWN. && LAT...LON 4011 10464 4000 10464 4000 10479 4010 10475 $$ BARJENBRUCH
2 follow-up statements
305 WGUS75 KBOU 270156 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 756 PM MDT WED SEP 26 2012 COC123-270345- /O.CON.KBOU.FF.W.0027.000000T0000Z-120927T0345Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ WELD CO- 756 PM MDT WED SEP 26 2012 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 PM MDT FOR EXTREME SOUTH CENTRAL WELD COUNTY... AT 751 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THE HEAVY RAIN NEAR HUDSON...OR ABOUT 23 MILES SOUTH OF GREELEY... HAD ENDED. LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LOCHBUIE AND HUDSON. DOPPLER RADAR ESTIMATES THAT AROUND 3 INCHES OF RAIN FELL FROM THE STORMS EARLIER THIS EVENING. THE HEAVIEST RAIN WAS CENTERED ABOUT 3 MILES WEST OF HUDSON AND 3 MILES NORTH OF LOCHBUIE. PRECAUTIONARY/PREPAREDNESS ACTIONS... EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL CREEKS AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES AND ARROYOS...AS WELL AS FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS. BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING. && LAT...LON 4011 10464 4000 10464 4000 10479 4010 10475 $$ BARJENBRUCH
701 WGUS75 KBOU 270306 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 906 PM MDT WED SEP 26 2012 COC123-270316- /O.CAN.KBOU.FF.W.0027.000000T0000Z-120927T0345Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ WELD CO- 906 PM MDT WED SEP 26 2012 ...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTH CENTRAL WELD COUNTY... THE WELD COUNTY SHERIFF REPORTED NO ADDITIONAL FLOODING ISSUES. LAT...LON 4011 10464 4000 10464 4000 10479 4010 10475 $$ BARJENBRUCH
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 26, 6:20 PM MDT | Areal Flood Advisory | BOU | Weld | 85 min |
| Sep 27, 1:15 PM MDT | Tornado Warning | BOU | Douglas | 29 min |
| Sep 27, 1:29 PM MDT | Tornado Warning | BOU | Elbert | 31 min |
| Sep 27, 4:40 PM MDT | Areal Flood Advisory | BOU | Washington | 80 min |
| Sep 27, 5:00 PM MDT | Special Weather Statement | BOU | Weld | 30 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.