Alert archive / Arizona / Flash Flood Warnings in 2011
Flash Flood Warning 21, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this flash flood warning at Jul 20, 2011, 2:51 PM MDT for Navajo County, Arizona. It was in force for 84 min. 1 report 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
- Jul 20, 2011, 2:51 PM MDT (20:51 UTC)
- Expired
- Jul 20, 2011, 4:15 PM MDT
- In force
- 84 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Flood severity
- None
County Navajo County, AZ
The radar
The Flagstaff radar (KFSX), 139 km from the middle of the area, began a volume at 20:52 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 20, 3:00 PM MDT | FLOOD | Whiteriver, AZ | FOREST SERVICE OFFICIAL REPORTED SIGNIFICANT DEBRIS FLOWS AND STREET FLOODING IN THE WALLOW BURN AREA. LARGE ROCKS AND SAND WERE CARRIED ONTO ROADWAYS AND ALL DRAINAGES WERE FULL. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Phoenix, AZ (KPSR), launched 12:00Z, 8.9 hours before the alert went out and 192 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
- 91 J/kg
- Mixed-layer CIN
- -298 J/kg
- Mixed-layer LCL
- 2251 m above ground
- 0-6 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- 21 m²/s²
- 0-3 km storm-relative helicity
- 48 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
939 WGUS55 KFGZ 202051 FFWFGZ AZC017-202215- /O.NEW.KFGZ.FF.W.0021.110720T2051Z-110720T2215Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE FLAGSTAFF AZ 151 PM MST WED JUL 20 2011 THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A * FLASH FLOOD WARNING FOR... EXTREME SOUTHEASTERN NAVAJO COUNTY IN NORTHEAST ARIZONA... * UNTIL 315 PM MST * AT 147 PM MST...FLASH FLOODING WAS REPORTED FROM A THUNDERSTORM OVER THE WARNED AREA. PRECAUTIONARY/PREPAREDNESS ACTIONS... THE HEAVY RAIN WILL LIKELY TRIGGER LIFE-THREATENING FLASH FLOODS AND DEBRIS FLOWS WITHIN AND DOWNHILL FROM THE LOCUST FIRE BURN AREA. FLASH FLOODING WILL LIKELY BEGIN WITHIN A FEW MINUTES AND MAY HAVE ALREADY STARTED. IF YOU CAN NOT MOVE SAFELY OUT OF THE WAY OF FLASH FLOODING...IT IS BEST TO SHELTER IN PLACE IN A STURDY STRUCTURE. AREAS IMPACTED BY THIS WARNING INCLUDE THOSE LOCATIONS IN WHITERIVER FROM LOCUST STREET TO KNOTS LANDING ROAD BETWEEN THE BURN AREA AND THE WHITE RIVER...INCLUDING HIGHWAY 73. && LAT...LON 3387 10995 3383 10995 3384 10998 3387 10998 $$ DJO
3 follow-up statements
202 WGUS75 KFGZ 202120 FFSFGZ FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE FLAGSTAFF AZ 220 PM MST WED JUL 20 2011 AZC017-202215- /O.CON.KFGZ.FF.W.0021.000000T0000Z-110720T2215Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NAVAJO AZ- 220 PM MST WED JUL 20 2011 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 PM MST FOR EXTREME SOUTHEASTERN NAVAJO COUNTY... AT 215 PM MST...VERY HEAVY RAIN CONTINUES OVER THE LOCUST FIRE BURN AREA. RADAR ESTIMATES THAT AMOUNTS IN EXCESS OF 1 INCH HAVE ALREADY FALLEN...WITH AN ADDITIONAL HALF INCH POSSIBLE. THE HEAVY RAIN WILL LIKELY TRIGGER LIFE-THREATENING FLASH FLOODS AND DEBRIS FLOWS WITHIN AND DOWNHILL FROM THE LOCUST FIRE BURN AREA. FLASH FLOODING HAS LIKELY ALREADY BEGUN. IF YOU CAN NOT MOVE SAFELY OUT OF THE WAY OF FLASH FLOODING...IT IS BEST TO SHELTER IN PLACE IN A STURDY STRUCTURE. AREAS IMPACTED BY THIS WARNING INCLUDE THOSE LOCATIONS IN WHITERIVER FROM LOCUST STREET TO KNOTS LANDING ROAD BETWEEN THE BURN AREA AND THE WHITE RIVER...INCLUDING HIGHWAY 73. PRECAUTIONARY/PREPAREDNESS ACTIONS... THE HEAVY RAIN WILL LIKELY TRIGGER LIFE-THREATENING FLASH FLOODS AND DEBRIS FLOWS WITHIN AND DOWNHILL FROM THE LOCUST FIRE BURN AREA. FLASH FLOODING HAS LIKELY ALREADY BEGUN. IF YOU CAN NOT MOVE SAFELY OUT OF THE WAY OF FLASH FLOODING...IT IS BEST TO SHELTER IN PLACE IN A STURDY STRUCTURE. && LAT...LON 3387 10995 3383 10995 3384 10998 3387 10998 $$ DJO
190 WGUS75 KFGZ 202205 FFSFGZ FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE FLAGSTAFF AZ 305 PM MST WED JUL 20 2011 AZC017-202215- /O.CON.KFGZ.FF.W.0021.000000T0000Z-110720T2215Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NAVAJO AZ- 305 PM MST WED JUL 20 2011 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 PM MST FOR EXTREME SOUTHEASTERN NAVAJO COUNTY... AT 301 PM MST...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED THAT FLOODING AND DEBRIS FLOWS HAD AFFECTED PORTIONS OF WHITERIVER DOWNHILL FROM THE LOCUST FIRE BURN AREA. AT LEAST ONE RESIDENCE WAS FLOODED AND AREA ROADWAYS...INCLUDING HIGHWAY 73...HAD BEEN FLOODED OVER. WATER WAS RECEDING AT THE TIME. LAT...LON 3387 10995 3383 10995 3384 10998 3387 10998 $$ DJO
897 WGUS75 KFGZ 202218 FFSFGZ FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE FLAGSTAFF AZ 318 PM MST WED JUL 20 2011 AZC017-202225- /O.EXP.KFGZ.FF.W.0021.000000T0000Z-110720T2215Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ NAVAJO AZ- 318 PM MST WED JUL 20 2011 ...THE FLASH FLOOD WARNING HAS EXPIRED FOR EXTREME SOUTHEASTERN NAVAJO COUNTY... THE FLASH FLOOD WARNING FOR THE LOCUST FIRE BURN AREA AND THE COMMUNITY OF WHITERIVER HAS BEEN ALLOWED TO EXPIRE. HEAVY RAIN HAD ENDED AND LAW ENFORCEMENT OFFICIALS REPORTED THAT FLOOD WATERS HAD RECEDED. FLOODING AND DEBRIS FLOWS OCCURRED... AFFECTING AREA ROADWAYS INCLUDING HIGHWAY 73. AT LEAST ONE HOME WAS FLOODED. LAT...LON 3387 10995 3383 10995 3384 10998 3387 10998 $$ DJO
The office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 1:17 PM MDT | Flash Flood Warning | FGZ | Apache | 3 hr |
| Jul 20, 1:47 PM MDT | Areal Flood Advisory | FGZ | Coconino, Gila, Navajo | 91 min |
Nearby
Flash Flood Warnings in Arizona, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.