Alert archive / Nevada / Red Flag Warnings in 2011
Red Flag Warning 1, NWS Las Vegas, NV
NWS Las Vegas, NV issued this red flag warning at Apr 29, 2011, 2:53 PM PDT for Clark County, Nevada; San Bernardino County, California; Mohave County, Arizona. It took effect at Apr 30, 2011, 2:00 AM PDT. It was in force for 19 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Apr 29, 2011, 2:53 PM PDT (21:53 UTC)
- In effect from
- Apr 30, 2011, 2:00 AM PDT
- Expired
- Apr 30, 2011, 9:00 PM PDT
- In force
- 19 hr
- Issued by
- NWS Las Vegas, NV
Counties Mohave County, AZ, San Bernardino County, CA, Clark County, NV
The radar
The Las Vegas radar (KESX), 15 km from the middle of the area, began a volume at 21:59 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
Las Vegas, NV (KVEF), launched 12:00Z, 9.9 hours before the alert went out and 101 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3438 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- -53 m²/s²
- 0-3 km storm-relative helicity
- 120 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
564 WWUS85 KVEF 292153 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 253 PM PDT FRI APR 29 2011 .A STORM SYSTEM WILL MOVE FROM THE PACIFIC NORTHWEST THROUGH THE GREAT BASIN TODAY AND SATURDAY. STRONG NORTH WINDS BEHIND THE COLD FRONT WILL OCCUR WITHIN THE COLORADO RIVER VALLEY SATURDAY. AZZ101-CAZ229-NVZ466-300600- /O.UPG.KVEF.FW.A.0002.110430T1700Z-110501T0400Z/ /O.NEW.KVEF.FW.W.0001.110430T1500Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 253 PM PDT FRI APR 29 2011 /253 PM MST FRI APR 29 2011/ ...RED FLAG WARNING IN EFFECT FROM 8 AM PDT /8 AM MST/ TO 9 PM PDT /9 PM MST/ SATURDAY... THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A RED FLAG WARNING FOR STRONG WINDS AND LOW RELATIVE HUMIDITY FIRE WEATHER ZONES 101 - 229 AND 466...WHICH IS IN EFFECT FROM 8 AM PDT /8 AM MST/ TO 9 PM PDT /9 PM MST/ SATURDAY. THE FIRE WEATHER WATCH IS NO LONGER IN EFFECT. NORTH WINDS WILL INCREASE DOWN THE COLORADO RIVER VALLEY FOLLOWING THE PASSAGE OF A COLD FRONT FRIDAY NIGHT. SUSTAINED NORTH WINDS OF 25 TO 30 MPH WITH GUSTS OVER 45 MPH ARE POSSIBLE. EVEN THOUGH TEMPERATURES WILL BE COLDER ON SATURDAY VERY DRY AIR BEHIND THE COLD FRONT WILL LEAD TO RELATIVE HUMIDITY VALUES AS LOW AS 5 PERCENT. PRECAUTIONARY/PREPAREDNESS ACTIONS... A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE EITHER OCCURRING OR ARE IMMINENT. A COMBINATION OF STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE EXTREME FIRE GROWTH POTENTIAL. && $$
5 follow-up statements
091 WWUS85 KVEF 300528 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 1028 PM PDT FRI APR 29 2011 AZZ101-CAZ229-NVZ466-301700- /O.CON.KVEF.FW.W.0001.110430T1500Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 1028 PM PDT FRI APR 29 2011 /1028 PM MST FRI APR 29 2011/ ...RED FLAG WARNING REMAINS IN EFFECT FROM 8 AM PDT /8 AM MST/ TO 9 PM PDT /9 PM MST/ SATURDAY... A RED FLAG WARNING REMAINS IN EFFECT FROM 8 AM PDT /8 AM MST/ TO 9 PM PDT /9 PM MST/ SATURDAY FOR THE LAKE MEAD NATIONAL RECREATION AREA AND COLORADO RIVER VALLEY. NORTH WINDS WILL INCREASE DOWN THE COLORADO RIVER VALLEY SATURDAY BEHIND A COLD FRONT. SUSTAINED NORTH WINDS OF 25 TO 30 MPH WITH GUSTS OVER 45 MPH ARE LIKELY. EVEN THOUGH TEMPERATURES WILL BE COOLER ON SATURDAY VERY DRY AIR BEHIND THE COLD FRONT WILL LEAD TO RELATIVE HUMIDITY VALUES AS LOW AS 5 PERCENT. WINDS WILL DECREASE SATURDAY EVENING. PRECAUTIONARY/PREPAREDNESS ACTIONS... A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE EITHER OCCURRING OR ARE IMMINENT. A COMBINATION OF STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE EXTREME FIRE GROWTH POTENTIAL. && $$
723 WWUS85 KVEF 300857 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 157 AM PDT SAT APR 30 2011 AZZ101-CAZ229-NVZ466-301700- /O.EXT.KVEF.FW.W.0001.110430T0900Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 157 AM PDT SAT APR 30 2011 /157 AM MST SAT APR 30 2011/ ...RED FLAG WARNING NOW IN EFFECT UNTIL 9 PM PDT /9 PM MST/ THIS EVENING DUE TO STRONG WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 101 - 229 AND 466... THE RED FLAG WARNING FOR THE COLORADO RIVER VALLEY IS NOW IN EFFECT UNTIL 9 PM THIS EVENING. SUSTAINED NORTH WINDS OF 25 TO 30 MPH WITH GUSTS OVER 45 MPH WILL COMBINE WITH RELATIVE HUMIDITIES AS LOW AS 5 PERCENT TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS TODAY. PRECAUTIONARY/PREPAREDNESS ACTIONS... A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE EITHER OCCURRING OR ARE IMMINENT. A COMBINATION OF STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE EXTREME FIRE GROWTH POTENTIAL. && $$ MORGAN
265 WWUS85 KVEF 301654 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 954 AM PDT SAT APR 30 2011 AZZ101-CAZ229-NVZ466-010100- /O.CON.KVEF.FW.W.0001.000000T0000Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 954 AM PDT SAT APR 30 2011 /954 AM MST SAT APR 30 2011/ ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/ THIS EVENING... A RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/ THIS EVENING FOR THE COLORADO RIVER VALLEY. SUSTAINED NORTH WINDS OF 25 TO 30 MPH WITH GUSTS OVER 45 MPH WILL COMBINE WITH RELATIVE HUMIDITIES AS LOW AS 5 PERCENT TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS TODAY. AS OF 930 THIS MORNING...RELATIVE HUMIDITY VALUES HAD GENERALLY LOWERED TO 15 PERCENT OR LESS WITH SOME REMOTE SENSORS ALREADY REPORTING LESS THAN 10 PERCENT. MEANWHILE WIND GUSTS TO OVER 40 MPH HAD ALSO BEEN REPORTED IN THE NEEDLES AND BULLHEAD CITY AREAS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE EITHER OCCURRING OR ARE IMMINENT. A COMBINATION OF STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE EXTREME FIRE GROWTH POTENTIAL. && $$
282 WWUS85 KVEF 302234 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 334 PM PDT SAT APR 30 2011 AZZ101-CAZ229-NVZ466-010400- /O.CON.KVEF.FW.W.0001.000000T0000Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 334 PM PDT SAT APR 30 2011 /334 PM MST SAT APR 30 2011/ ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/ THIS EVENING... A RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/ THIS EVENING FOR THE LAKE MEAD NRA/COLORADO RIVER AZ SIDE...LOWER COLORADO RIVER VALLEY...LAKE MEAD NRA/COLORADO RIVER NV SIDE. SUSTAINED NORTH WINDS OF 20 TO 25 MPH WITH GUSTS TO OVER 35 MPH ARE EXPECTED TO CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON BEFORE DECREASING THIS EVENING. THESE WINDS ALONG WITH MINIMUM RELATIVE HUMIDITY VALUES OF BETWEEN 5 AND 10 PERCENT WILL CONTINUE TO CREATE CRITICAL FIRE WEATHER CONDITIONS. ALTHOUGH POOR RELATIVE HUMIDITY RECOVERIES ARE EXPECTED TONIGHT... THE DECREASING WINDS WILL DECREASE THE CURRENT CRITICAL CONDITIONS OVERNIGHT. GUSTY WINDS ARE ONCE AGAIN EXPECTED ON SUNDAY...BUT WIND SPEEDS ARE EXPECTED TO BE BELOW THE 35 MPH THRESHOLD NEEDED FOR A RED FLAG WARNING. PRECAUTIONARY/PREPAREDNESS ACTIONS... A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE EITHER OCCURRING OR ARE IMMINENT. A COMBINATION OF STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL CREATE EXTREME FIRE GROWTH POTENTIAL. && $$
986 WWUS85 KVEF 010334 RFWVEF URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE LAS VEGAS NV 834 PM PDT SAT APR 30 2011 AZZ101-CAZ229-NVZ466-010445- /O.EXP.KVEF.FW.W.0001.000000T0000Z-110501T0400Z/ LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY- LAKE MEAD NRA/COLORADO RIVER-NV SIDE- 834 PM PDT SAT APR 30 2011 /834 PM MST SAT APR 30 2011/ ...RED FLAG WARNING WILL EXPIRE AT 9 PM PDT /9 PM MST/ THIS EVENING... THE RED FLAG WARNING FOR THE LAKE MEAD NATIONAL RECREATION AREA AND COLORADO RIVER VALLEY WILL EXPIRE AT 9 PM PDT /9 PM MST/ THIS EVENING. WINDS HAVE BEEN DECREASING THIS EVENING AND WILL REMAIN BELOW RED FLAG CRITERIA OVERNIGHT. OVERNIGHT HUMIDITY IS EXPECTED TO BE POOR HOWEVER. $$
The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 29, 2:49 AM PDT | Wind Advisory | VEF | 37 hr | |
| Apr 28, 9:25 PM PDT | High Wind Warning | VEF | Inyo | 10 hr |
| Apr 29, 9:56 AM PDT | Dust Storm Warning | VEF | 2 hr |
Nearby
Red Flag Warnings in Nevada, 2011Red Flag Warnings in California, 2011Red Flag Warnings in Arizona, 2011Every red flag 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.