Alert archive / Arizona / Flash Flood Warnings in 2018

Flash Flood Warning 49, NWS Phoenix, AZ

August 10, 2018Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 10, 2018, 11:31 PM MST for Maricopa County, Arizona. It was in force for 119 min. 4 reports 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
Aug 10, 2018, 11:31 PM MST (06:31 UTC)
Expired
Aug 11, 2018, 1:30 AM MST
In force
119 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Flood severity
None

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 40 km from the middle of the area, began a volume at 06:31 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

TimeReportWhereRemark
Aug 10, 11:32 PM MSTHEAVY RAIN 0.823 Nne Phoenix, AZCORRECTS PREVIOUS HEAVY RAIN REPORT FROM 3 NNE PHOENIX.
Aug 10, 11:32 PM MSTHEAVY RAIN 0.823 Nne Phoenix, AZ
Aug 10, 11:46 PM MSTHEAVY RAIN 0.671 Nnw Phoenix, AZ
Aug 11, 12:00 AM MSTFLASH FLOOD6 W Paradise Valley, AZPUBLIC PHOENIX RESIDENT REPORTED ROARING WATERS FLOWING DOWN A WASH BEHIND THEIR HOUSE. THIS WAS IS BEHIND EAST MYRTLE AVENUE AND RUNS UNDER THE 51.

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 00:00Z, 6.5 hours before the alert went out and 11 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 2018-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 276 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 2018-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 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
276 J/kg
Mixed-layer CIN
-239 J/kg
Mixed-layer LCL
2297 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

397 
WGUS55 KPSR 110631
FFWPSR
AZC013-110830-
/O.NEW.KPSR.FF.W.0049.180811T0631Z-180811T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
1131 PM MST FRI AUG 10 2018

The National Weather Service in Phoenix has issued a

* Flash Flood Warning for...
  Maricopa County in south central Arizona...

* Until 130 AM MST.

* At 1130 PM MST, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is expected to
  begin shortly.

* Some locations that will experience flooding include...
  Phoenix, Mesa, Tempe, Paradise Valley, Laveen, Mesa Riverview Mall,
  Tempe Marketplace, Papago Park, Piestewa Peak Park, Arizona Mills
  Mall, North Mountain Park, South Phoenix, Arizona State
  Fairgrounds, Downtown Phoenix and Metro Center.

* This includes the following highways...
  AZ Interstate 10 between mile markers 141 and 157.
  AZ Interstate 17 between mile markers 195 and 213.
  AZ Route 51 between mile markers 1 and 15.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

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

&&

LAT...LON 3370 11196 3350 11196 3345 11177 3336 11195
      3336 11215 3363 11215

$$

AD
2 follow-up statements
357 
WGUS75 KPSR 110642
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
1142 PM MST FRI AUG 10 2018

AZC013-110830-
/O.CON.KPSR.FF.W.0049.000000T0000Z-180811T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maricopa AZ-
1142 PM MST FRI AUG 10 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 AM MST FOR
MARICOPA COUNTY...

At 1142 PM MST, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Up to one inch of rain has already 
fallen in some locations. Flash flooding is expected to begin 
shortly.

Some locations that will experience flooding include...
Phoenix, Mesa, Tempe, Paradise Valley, Laveen, Mesa Riverview Mall,
Tempe Marketplace, Papago Park, Piestewa Peak Park, Arizona Mills
Mall, North Mountain Park, South Phoenix, Arizona State Fairgrounds,
Downtown Phoenix and Metro Center.

This includes the following highways...
AZ Interstate 10 between mile markers 141 and 157.
AZ Interstate 17 between mile markers 195 and 213.
AZ Route 51 between mile markers 1 and 15.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

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

&&

LAT...LON 3370 11196 3350 11196 3345 11177 3336 11195
      3336 11215 3363 11215

$$

AD
484 
WGUS75 KPSR 110830
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
130 AM MST SAT AUG 11 2018

AZC013-110837-
/O.EXP.KPSR.FF.W.0049.000000T0000Z-180811T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maricopa AZ-
130 AM MST SAT AUG 11 2018

...THE FLASH FLOOD WARNING FOR MARICOPA COUNTY WILL EXPIRE AT 130 AM
MST...

An Areal Flood Warning remains in effect for portions of south 
Scottsdale including the Indian Bend Wash. Other locations within the 
warned area will see water receding. Additional rainfall is possible 
through 5 AM with a Flash Flood Watch in effect through 5 AM. Please 
continue to heed any remaining road closures.

LAT...LON 3370 11196 3350 11196 3345 11177 3336 11195
      3336 11215 3363 11215

$$

CK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 8:13 PM MSTSpecial Weather StatementPSRGila47 min
Aug 10, 8:25 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa, Pinal35 min
Aug 10, 9:00 PM MSTSpecial Weather StatementPSRGila45 min
Aug 10, 9:11 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal94 min
Aug 10, 9:14 PM MSTSpecial Weather StatementPSRPinal46 min
Aug 10, 9:40 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa35 min
Aug 10, 9:59 PM MSTAreal Flood AdvisoryPSRGila, Maricopa3 hr
Aug 10, 10:01 PM MSTSpecial Weather StatementPSR44 min
Aug 10, 10:08 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa37 min
Aug 10, 10:15 PM MSTAreal Flood AdvisoryPSRMaricopa, Pinal3 hr
Aug 10, 10:26 PM MSTSpecial Weather StatementPSRMaricopa49 min
Aug 10, 10:35 PM MSTFlash Flood WarningPSRGila, Maricopa, Pinal3 hr
Aug 10, 10:37 PM MSTDust Storm WarningPSRMaricopa14 min
Aug 10, 10:39 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa51 min
Aug 10, 10:46 PM MSTSpecial Weather StatementPSRMaricopa44 min
Aug 10, 10:53 PM MSTAreal Flood AdvisoryPSRMaricopa112 min
Aug 10, 11:02 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal43 min
Aug 10, 11:26 PM MSTSpecial Weather StatementPSRMaricopa49 min
Aug 10, 11:30 PM MSTSpecial Weather StatementPSR30 min
Aug 10, 11:35 PM MSTAreal Flood AdvisoryPSRMaricopa, Pinal3 hr
Aug 10, 11:38 PM MSTDust Storm AdvisoryPSRMaricopa, Pinal52 min
Aug 11, 12:12 AM MSTSpecial Weather StatementPSRMaricopa48 min
Aug 11, 12:20 AM MSTDust Storm AdvisoryPSRLa Paz, Maricopa, Yuma40 min
Aug 11, 12:49 AM MSTAreal Flood WarningPSRMaricopa6 hr
Aug 11, 12:54 AM MSTFlash Flood WatchPSRGila, Maricopa, Pinal4 hr
Aug 11, 12:58 AM MSTSpecial Weather StatementPSRMaricopa47 min
Aug 11, 1:49 AM MSTSpecial Weather StatementPSR41 min
Aug 11, 1:54 AM MSTSpecial Weather StatementPSRMaricopa51 min
Aug 11, 2:22 AM MSTFlash Flood WarningPSRMaricopa3 hr
Aug 11, 5:37 AM MSTSpecial Weather StatementPSRLa Paz38 min
Aug 11, 6:18 AM MSTSpecial Weather StatementPSRLa Paz42 min
Aug 11, 6:41 AM MSTAreal Flood AdvisoryPSRLa Paz, Yuma3 hr
Aug 11, 6:56 AM MSTSpecial Weather StatementPSR49 min
Aug 11, 8:15 AM MSTSpecial Weather StatementPSRLa Paz45 min
Aug 11, 9:14 AM MSTSpecial Weather StatementPSRLa Paz31 min
Aug 11, 9:52 AM MSTAreal Flood WarningPSRLa Paz, Yuma38 min

Nearby

Flash Flood Warnings in Arizona, 2018Every flash flood warning in 2018

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.