Alert archive / Arizona / Red Flag Warnings in 2021

Red Flag Warning 4, NWS Phoenix, AZ

May 22, 2021Gila County, Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this red flag warning at May 22, 2021, 3:11 AM MST for Gila County, Maricopa County, Pinal County, Arizona. It took effect at May 22, 2021, 12:00 PM MST. It was in force for 6 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
May 22, 2021, 3:11 AM MST (10:11 UTC)
In effect from
May 22, 2021, 12:00 PM MST
Expired
May 22, 2021, 6:00 PM MST
In force
6 hr
Issued by
NWS Phoenix, AZ

Counties Gila County, AZ, Maricopa County, AZ, Pinal County, AZ

The radar

The Phoenix radar (KIWA), 13 km from the middle of the area, began a volume at 10:14 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

Tuscon, AZ (KTUS), launched 00:00Z, 10.2 hours before the alert went out and 145 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.

Skew-T log-pSkew-T log-p diagram, Tuscon, AZ at 00:00Z on 2021-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 00:00Z on 2021-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3593 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

537 
WWUS85 KPSR 221011
RFWPSR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Phoenix AZ
311 AM MST Sat May 22 2021

AZZ133-230100-
/O.NEW.KPSR.FW.W.0004.210522T1900Z-210523T0100Z/
Southern Gila County/Tonto National Forest Foothills-
311 AM MST Sat May 22 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 6 PM MST THIS
EVENING FOR STRONG WINDS, LOW RELATIVE HUMIDITY AND VERY HIGH 
FIRE DANGER FOR SOUTHEASTERN GILA COUNTY...

The National Weather Service in Phoenix has issued a Red Flag
Warning for strong winds, low relative humidity and high fire 
danger, which is in effect from noon today to 6 PM MST this 
evening.

* AFFECTED AREA...Southern Gila County/Tonto National Forest 
  Foothills.

* TIMING...This afternoon.

* WINDS...Southwest 15 to 25 mph with gusts up to 40 mph.

* RELATIVE HUMIDITY...As low as 7 percent.

* IMPACTS...Fuels are dry and fire danger is very high. These 
  conditions combined with low relative humidity and strong winds 
  will lead to widespread hazardous fire weather conditions.
  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please advise the appropriate officials and fire crews in the
field of this red flag warning.

&&

$$

National Weather Service Phoenix is on the internet at

weather.gov/phoenix
2 follow-up statements
662 
WWUS85 KPSR 222219
RFWPSR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Phoenix AZ
319 PM MST Sat May 22 2021

AZZ133-230100-
/O.CON.KPSR.FW.W.0004.000000T0000Z-210523T0100Z/
Southern Gila County/Tonto National Forest Foothills-
319 PM MST Sat May 22 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 PM MST THIS EVENING
FOR STRONG WINDS, LOW RELATIVE HUMIDITY AND VERY HIGH FIRE DANGER
FOR SOUTHEASTERN GILA COUNTY...

* AFFECTED AREA...Southern Gila County/Tonto National Forest 
  Foothills.

* TIMING...Until 6 pm MST.

* WINDS...Southwest 20 to 25 mph with gusts up to 35 mph.

* RELATIVE HUMIDITY...As low as 7 percent.

* IMPACTS...Fuels are dry and fire danger is very high. These 
  conditions combined with low relative humidity and strong 
  winds will lead to widespread hazardous fire weather 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please advise the appropriate officials and fire crews in the
field of this red flag warning.

&&

$$

National Weather Service Phoenix is on the internet at

weather.gov/phoenix
959 
WWUS85 KPSR 230049
RFWPSR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Phoenix AZ
549 PM MST Sat May 22 2021

AZZ133-230200-
/O.EXP.KPSR.FW.W.0004.000000T0000Z-210523T0100Z/
Southern Gila County/Tonto National Forest Foothills-
549 PM MST Sat May 22 2021

...RED FLAG WARNING WILL EXPIRE AT 6 PM MST THIS EVENING FOR
STRONG WINDS, LOW RELATIVE HUMIDITY AND HIGH FIRE DANGER FOR
SOUTHERN GILA COUNTY...

Winds will weaken into the evening while RH values recover 
modestly overnight. Therefore, the Red Flag Warning will expire at
6 PM MST. 

$$

National Weather Service Phoenix is on the internet at

weather.gov/phoenix

Nearby

Red Flag Warnings in Arizona, 2021Every red flag warning in 2021

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.