Alert archive / Colorado / Flash Flood Warnings in 2011
Flash Flood Warning 29, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 18, 2011, 6:08 PM MDT for Larimer 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
- Jul 18, 2011, 6:08 PM MDT (00:08 UTC)
- Expired
- Jul 18, 2011, 8:13 PM MDT
- In force
- 2 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
County Larimer County, CO
The radar
The Cheyenne radar (KCYS), 86 km from the middle of the area, began a volume at 00:09 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, 0.1 hours before the alert went out and 214 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
- 609 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 2901 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 2 m²/s²
- 0-3 km storm-relative helicity
- 11 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
986 WGUS55 KBOU 190008 FFWBOU COC069-190300- /O.NEW.KBOU.FF.W.0029.110719T0008Z-110719T0300Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE DENVER CO 608 PM MDT MON JUL 18 2011 THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * FLASH FLOOD WARNING FOR... CENTRAL LARIMER COUNTY IN NORTH CENTRAL COLORADO * UNTIL 900 PM MDT * AT 603 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY RAIN FROM A THUNDERSTORM NEAR RUSTIC...OR 25 MILES WEST OF FORT COLLINS. THIS STORM WAS MOVING NORTH AT 20 MPH. * LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO RUSTIC AND PINGREE PARK. * THE WATERWAYS AFFECTED BY THIS ADVISORY INCLUDE LITTLE BEAVER CREEK...FISH CREEK...BENNET CREEK...THE SOUTH FORK OF THE CACHE LA POUDRE RIVER AND PENNOCK CREEK. RADAR ESTIMATES THAT 1.50 TO 4.00 INCHES OF RAIN HAVE FALLEN IN THE WARNING AREA SINCE 2:45 PM MDT THIS AFTERNOON. THE INDIVIDUAL STORMS ARE MOVING AT AROUND 20 MPH...BUT MANY STORMS HAVE BEEN MOVING OVER THE SAME AREAS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE. TURN AROUND...DO NOT DROWN. EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO TRIGGER ROCK SLIDES OR DEBRIS FLOWS IN STEEP TERRAIN. && LAT...LON 4071 10557 4066 10540 4049 10553 4056 10569 $$ RJK
3 follow-up statements
792 WGUS75 KBOU 190106 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 706 PM MDT MON JUL 18 2011 COC069-190300- /O.CON.KBOU.FF.W.0029.000000T0000Z-110719T0300Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ LARIMER CO- 706 PM MDT MON JUL 18 2011 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 PM MDT FOR CENTRAL LARIMER COUNTY... AT 704 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED RAIN WAS ENDING OVER CENTRAL LARIMER COUNTY. LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO RUSTIC AND PINGREE PARK. DOPPLER RADAR ESTIMATES THAT OVER 3 INCHES OF RAIN MAY HAVE FALLEN NEAR PINGREE PARK THIS AFTERNOON. THE WATERWAYS AFFECTED BY THIS ADVISORY INCLUDE LITTLE BEAVER CREEK...FISH CREEK...BENNET CREEK...THE SOUTH FORK OF THE CACHE LA POUDRE RIVER AND PENNOCK CREEK. PRECAUTIONARY/PREPAREDNESS ACTIONS... EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO TRIGGER ROCK SLIDES OR DEBRIS FLOWS IN STEEP TERRAIN. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER CLIMB TO HIGHER GROUND. && LAT...LON 4071 10557 4066 10540 4049 10553 4056 10569 $$
383 WGUS75 KBOU 190129 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 729 PM MDT MON JUL 18 2011 COC069-190300- /O.CON.KBOU.FF.W.0029.000000T0000Z-110719T0300Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ LARIMER CO- 729 PM MDT MON JUL 18 2011 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 PM MDT FOR CENTRAL LARIMER COUNTY... AT 725 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED FLASH FLOODING FROM A THUNDERSTORM 3 MILES NORTHEAST OF PINGREE PARK...OR ABOUT 24 MILES WEST OF FORT COLLINS. THIS STORM WAS NEARLY STATIONARY. LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO RUSTIC AND PINGREE PARK. THE WATERWAYS AFFECTED BY THIS ADVISORY INCLUDE LITTLE BEAVER CREEK...FISH CREEK...BENNET CREEK...THE SOUTH FORK OF THE CACHE LA POUDRE RIVER AND PENNOCK CREEK. RADAR ESTIMATES THAT 1.75 TO 4.50 INCHES OF RAIN HAVE FALLEN IN THE WARNING AREA SINCE 2:45 PM MDT THIS AFTERNOON. THE INDIVIDUAL STORMS ARE MOVING AT AROUND 20 MPH...BUT MANY STORMS HAVE BEEN MOVING OVER THE SAME AREAS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE. TURN AROUND...DO NOT DROWN. EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO TRIGGER ROCK SLIDES OR DEBRIS FLOWS IN STEEP TERRAIN. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER CLIMB TO HIGHER GROUND. && LAT...LON 4071 10557 4066 10540 4049 10553 4056 10569 $$
444 WGUS75 KBOU 190213 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 813 PM MDT MON JUL 18 2011 COC069-190219- /O.CAN.KBOU.FF.W.0029.000000T0000Z-110719T0300Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ LARIMER CO- 813 PM MDT MON JUL 18 2011 ...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR CENTRAL LARIMER COUNTY... THE HEAVY RAINFALL OVER THE WARNING AREA HAS ENDED NEARLY AN HOUR AGO AND LITTLE ADDITIONAL RAINFALL IS EXPECTED. THEREFORE THE FLASH FLOOD WARNING HAS BEEN CANCELLED. THERE HAVE NO REPORTS OF FLASH FLOODING. LAT...LON 4071 10557 4066 10540 4049 10553 4056 10569 $$
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 18, 6:57 PM MDT | Areal Flood Advisory | BOU | Summit | 93 min |
| Jul 18, 7:25 PM MDT | Flash Flood Warning | BOU | Summit | 95 min |
| Jul 18, 7:29 PM MDT | Areal Flood Advisory | BOU | Summit | 91 min |
| Jul 18, 8:30 PM MDT | Areal Flood Advisory | BOU | Park | 2 hr |
| Jul 18, 8:52 PM MDT | Flash Flood Warning | BOU | Summit | 113 min |
| Jul 18, 9:28 PM MDT | Areal Flood Advisory | BOU | Grand | 24 hr |
| Jul 18, 10:52 PM MDT | Areal Flood Advisory | BOU | Summit | 20 hr |
| Jul 19, 11:13 AM MDT | Flash Flood Watch | BOU | Boulder, Clear Creek, Gilpin, Grand, Jackson, Jefferson and 3 more | 9 hr |
| Jul 19, 2:53 PM MDT | Special Weather Statement | BOU | Gilpin | 37 min |
| Jul 19, 3:27 PM MDT | Flash Flood Warning | BOU | Boulder | 2 hr |
| Jul 19, 4:19 PM MDT | Special Weather Statement | BOU | Broomfield | 26 min |
| Jul 19, 4:21 PM MDT | Areal Flood Advisory | BOU | Clear Creek, Gilpin, Jefferson, Park | 95 min |
| Jul 19, 4:58 PM MDT | Special Weather Statement | BOU | Broomfield | 32 min |
| Jul 19, 5:09 PM MDT | Special Weather Statement | BOU | Larimer | 36 min |
| Jul 19, 5:11 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Weld | 49 min |
| Jul 19, 5:37 PM MDT | Special Weather Statement | BOU | Denver | 23 min |
| Jul 19, 5:59 PM MDT | Special Weather Statement | BOU | Denver | 31 min |
Nearby
Flash Flood Warnings in Colorado, 2011Every flash flood warning in 2011
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.