Alert archive / California / Red Flag Warnings in 2017
Red Flag Warning 1, NWS Las Vegas, NV
NWS Las Vegas, NV issued this red flag warning at Apr 20, 2017, 9:14 AM PDT for San Bernardino County, California; Clark County, Nevada; Mohave County, Arizona. It took effect at Apr 21, 2017, 10:00 AM PDT. It was in force for 10 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 20, 2017, 9:14 AM PDT (16:14 UTC)
- In effect from
- Apr 21, 2017, 10:00 AM PDT
- Expired
- Apr 21, 2017, 8:00 PM PDT
- In force
- 10 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 16:19 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, 4.2 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
- 3458 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 31 m²/s²
- 0-3 km storm-relative helicity
- 49 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
864 WWUS85 KVEF 201614 RFWVEF URGENT - FIRE WEATHER MESSAGE National Weather Service Las Vegas NV 914 AM PDT Thu Apr 20 2017 .Gusty north winds and low humidity will develop along the Colorado River Basin Friday morning, resulting in dangerous fire conditions. AZZ101-CAZ229-NVZ466-211200- /O.NEW.KVEF.FW.W.0001.170421T1700Z-170422T0300Z/ Lake Mead NRA/Colorado River-AZ side-Lower Colorado River Valley- Lake Mead NRA/Colorado River-NV side- 914 AM PDT Thu Apr 20 2017 /914 AM MST Thu Apr 20 2017/ ...RED FLAG WARNING IN EFFECT FROM 10 AM PDT /10 AM MST/ TO 8 PM PDT /8 PM MST/ FRIDAY FOR GUSTY WINDS AND LOW HUMIDITY... The National Weather Service in Las Vegas has issued a Red Flag Warning, which is in effect from 10 AM PDT /10 AM MST/ to 8 PM PDT /8 PM MST/ Friday. * AFFECTED AREA...In Arizona...Fire weather zone 101.In California...Fire weather zone 229. In Nevada...Fire weather zone 466. * TIMING...FRIDAY MORNING THROUGH EARLY FRIDAY EVENING. * WIND...SUSTAINED NORTH WINDS 15 TO 25 MPH WITH GUSTS TO AROUND 40 MPH. * HUMIDITY...5 TO 10 PERCENT. * IMPACTS...any fires that develop will likely spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ weather.gov/lasvegas
2 follow-up statements
492 WWUS85 KVEF 211159 RFWVEF URGENT - FIRE WEATHER MESSAGE National Weather Service Las Vegas NV 459 AM PDT Fri Apr 21 2017 .Gusty north winds and low humidity will develop along the Colorado River Basin Friday morning, resulting in dangerous fire conditions. AZZ101-CAZ229-NVZ466-220300- /O.CON.KVEF.FW.W.0001.170421T1700Z-170422T0300Z/ Lake Mead NRA/Colorado River-AZ side-Lower Colorado River Valley- Lake Mead NRA/Colorado River-NV side- 459 AM PDT Fri Apr 21 2017 /459 AM MST Fri Apr 21 2017/ ...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM PDT /10 AM MST/ THIS MORNING TO 8 PM PDT /8 PM MST/ THIS EVENING FOR GUSTY WINDS AND LOW HUMIDITY... * AFFECTED AREA...In Arizona...Fire weather zone 101.In California...Fire weather zone 229. In Nevada...Fire weather zone 466. * TIMING...This morning through early afternoon. * WIND...Sustained north winds 15 to 25 mph with gusts to around 40 mph. * HUMIDITY...5 to 10 percent. * IMPACTS...Any fires that develop will likely spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ weather.gov/lasvegas
798 WWUS85 KVEF 220248 RFWVEF URGENT - FIRE WEATHER MESSAGE National Weather Service Las Vegas NV 748 PM PDT Fri Apr 21 2017 AZZ101-CAZ229-NVZ466-220400- /O.EXP.KVEF.FW.W.0001.000000T0000Z-170422T0300Z/ Lake Mead NRA/Colorado River-AZ side-Lower Colorado River Valley- Lake Mead NRA/Colorado River-NV side- 748 PM PDT Fri Apr 21 2017 /748 PM MST Fri Apr 21 2017/ ...RED FLAG WARNING WILL EXPIRE AT 8 PM PDT /8 PM MST/ THIS EVENING FOR GUSTY WINDS AND LOW HUMIDITY... Winds have died down as expected and the Red Flag Warning will expire at 8PM. $$ weather.gov/lasvegas
The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 20, 2:45 AM PDT | Wind Advisory | VEF | San Bernardino | 36 hr |
Nearby
Red Flag Warnings in California, 2017Red Flag Warnings in Nevada, 2017Red Flag Warnings in Arizona, 2017Every red flag warning in 2017
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.