Alert archive / Arizona / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 604

July 5, 20114 counties in Arizona

The Storm Prediction Center issued this severe thunderstorm watch at Jul 5, 2011, 6:28 PM MST for 4 counties in Arizona. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 5, 2011, 6:28 PM MST (01:28 UTC)
Expired
Jul 5, 2011, 11:00 PM MST
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
65 kt

Counties La Paz County, AZ, Maricopa County, AZ, Pinal County, AZ, Yuma County, AZ

The radar

The Phoenix radar (KIWA), 147 km from the middle of the area, began a volume at 01:30 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 5, 7:24 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal51 min
Jul 5, 7:37 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal53 min
Jul 5, 7:54 PM MSTSevere Thunderstorm WarningPSRGila, Maricopa51 min
Jul 5, 9:03 PM MSTSevere Thunderstorm WarningPSRLa Paz57 min
Jul 5, 10:41 PM MSTSevere Thunderstorm WarningPSRYuma40 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 1.5 hours before the alert went out and 118 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 2011-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 608 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2011-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
608 J/kg
Mixed-layer CIN
-118 J/kg
Mixed-layer LCL
2434 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 5, 5:36 PM MSTMesoscale DiscussionSPCMaricopa, Pima, Pinal, Yuma54 min
Jul 5, 9:28 PM MSTMesoscale DiscussionSPCLa Paz, Yuma2 hr

Nearby

Severe Thunderstorm Watches in Arizona, 2011Every severe thunderstorm watch 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.