Alert archive / Arizona / Flash Flood Warnings in 2017

Flash Flood Warning 9, NWS Phoenix, AZ

July 18, 2017La Paz County, Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Jul 18, 2017, 8:02 PM MST for La Paz County, Maricopa County, Arizona. It was in force for 3 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, 2017, 8:02 PM MST (03:02 UTC)
Expired
Jul 18, 2017, 11:00 PM MST
In force
3 hr
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Flood severity
None

Counties La Paz County, AZ, Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 159 km from the middle of the area, began a volume at 03:03 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

Phoenix, AZ (KPSR), launched 00:00Z, 3.0 hours before the alert went out and 128 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, Phoenix, AZ at 00:00Z on 2017-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1393 joules per kilogram.LCLLFCEL10008507005003002001001 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, Phoenix, AZ at 00:00Z on 2017-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 square meters per square second.1939Sfc1 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
1393 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
1792 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
-19 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

223 
WGUS55 KPSR 190302
FFWPSR
AZC012-013-190600-
/O.NEW.KPSR.FF.W.0009.170719T0302Z-170719T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
802 PM MST TUE JUL 18 2017

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  Eastern La Paz County in west central Arizona...
  Maricopa County in south central Arizona...

* Until 1100 PM MST

* At 801 PM MST, Doppler radar indicated heavy rain across the warned
  area. Up to two inches of rain have already fallen. Flash flooding
  is already occurring.

* Some locations that will experience flooding include...
  Aguila, Wenden, Gladden and Salome. US Highway 60 may be subject 
  to flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 3384 11299 3374 11314 3374 11348 3380 11361
      3395 11347 3401 11329 3400 11300

$$

KW
2 follow-up statements
742 
WGUS75 KPSR 190331
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
831 PM MST TUE JUL 18 2017

AZC012-013-190600-
/O.CON.KPSR.FF.W.0009.000000T0000Z-170719T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Maricopa AZ-
831 PM MST TUE JUL 18 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1100 PM MST FOR
EAST CENTRAL LA PAZ AND MARICOPA COUNTIES...

At 829 PM MST, Doppler radar indicated heavy rain across the warned
area. Up to two inches of rain have already fallen. Flash flooding is
already occurring.

Some locations that will experience flooding include...
Wenden, Gladden and Aguila. 

Radar continues to indicate very heavy rain falling, especially 
between Wenden and Gladden with some rainfall rates of 2 to 2.5 
inches per hour along US Highway 60.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 3388 11309 3380 11322 3378 11345 3382 11357
      3395 11347 3399 11332 3400 11311

$$

Waters
937 
WGUS75 KPSR 190553
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1053 PM MST TUE JUL 18 2017

AZC012-013-190603-
/O.EXP.KPSR.FF.W.0009.000000T0000Z-170719T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Paz AZ-Maricopa AZ-
1053 PM MST TUE JUL 18 2017

...THE FLASH FLOOD WARNING FOR EAST CENTRAL LA PAZ AND MARICOPA
COUNTIES WILL EXPIRE AT 1100 PM MST...

The heavy rain has ended. Flood waters have receded. Flooding is no
longer expected to pose a threat. Please continue to heed any
remaining road closures.

LAT...LON 3388 11309 3380 11322 3378 11345 3382 11357
      3395 11347 3399 11332 3400 11311

$$

THW

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 18, 5:43 PM MSTFlash Flood WarningPSRMaricopa6 hr
Jul 18, 6:01 PM MSTSpecial Weather StatementPSRMaricopa44 min
Jul 18, 6:06 PM MSTSevere Thunderstorm WarningPSRMaricopa24 min
Jul 18, 6:11 PM MSTSpecial Weather StatementPSR49 min
Jul 18, 6:15 PM MSTSpecial Weather StatementPSR45 min
Jul 18, 6:26 PM MSTBlowing Dust AdvisoryPSRPinal3 hr
Jul 18, 6:40 PM MSTFlash Flood WarningPSRMaricopa3 hr
Jul 18, 7:26 PM MSTSpecial Weather StatementPSR49 min
Jul 18, 10:22 PM MSTAreal Flood AdvisoryPSRMaricopa, Pinal3 hr
Jul 19, 12:42 PM MSTAreal Flood AdvisoryPSRGila, Pinal2 hr
Jul 19, 1:10 PM MSTSpecial Weather StatementPSRMaricopa50 min
Jul 19, 2:32 PM MSTSpecial Weather StatementPSRGila28 min
Jul 19, 2:34 PM MSTSpecial Weather StatementPSRMaricopa26 min
Jul 19, 4:10 PM MSTSpecial Weather StatementPSR35 min
Jul 19, 4:57 PM MSTSpecial Weather StatementPSRPinal48 min

Nearby

Flash Flood Warnings in Arizona, 2017Every flash flood 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.