Alert archive / Arizona / Mesoscale Discussions in 2015

Mesoscale Discussion 1213

June 27, 20156 counties in Arizona

The Storm Prediction Center issued this mesoscale discussion at Jun 27, 2015, 2:01 PM MST for 6 counties in Arizona. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jun 27, 2015, 2:01 PM MST (21:01 UTC)
Expired
Jun 27, 2015, 4:30 PM MST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Cochise County, AZ, Gila County, AZ, Graham County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 72 km from the middle of the area, began a volume at 21:01 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 (KDMA), launched 12:00Z, 9.0 hours before the alert went out and 53 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 12:00Z on 2015-06-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 246 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, Tuscon, AZ at 12:00Z on 2015-06-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 square meters per square second.193958Sfc1 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
246 J/kg
Mixed-layer CIN
-415 J/kg
Mixed-layer LCL
1888 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

884 
ACUS11 KWNS 272101
SWOMCD
SPC MCD 272101 
AZZ000-272330-

MESOSCALE DISCUSSION 1213
NWS STORM PREDICTION CENTER NORMAN OK
0401 PM CDT SAT JUN 27 2015

AREAS AFFECTED...PORTIONS OF CENTRAL AND SOUTHERN ARIZONA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 272101Z - 272330Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THE AREA IS BEING MONITORED FOR AN INCREASING RISK OF SVR
TSTMS THIS AFTERNOON WITH A FEW SVR WIND GUSTS POSSIBLE.
HOWEVER...CONFIDENCE IN MORE THAN A MODEST-COVERAGE SVR EVENT IS
LIMITED AT THIS TIME...AND WW ISSUANCE IS PRESENTLY UNLIKELY.

DISCUSSION...VISIBLE SATELLITE IMAGERY AND MOSAIC RADAR LOOPS
INDICATE CONVECTIVE DEVELOPMENT UNDERWAY ALONG THE MOGOLLON RIM TO
THE WHITE MOUNTAINS AND INTO THE MOUNTAINS OF SERN AZ NEAR TUCSON.
THIS ACTIVITY IS DEVELOPING IN THE DIURNALLY HEATED/WELL MIXED
BOUNDARY LAYER AMIDST PW BETWEEN 1.0 AND 1.3 INCHES PER GPS DATA.
STRONG SFC HEATING IS FACILITATING THE DEVELOPMENT OF MODERATE
INSTABILITY...WHICH MAY ALLOW FOR UPDRAFTS TO INTENSIFY AS THEY
SPREAD WWD...AND WSWWD OFF THE RIM. WITH DCAPE AROUND 1200-1600 J/KG
IN THE WELL/DEEPLY MIXED PBL...CONFIDENCE IS INCREASING THAT STRONG
OUTFLOW WINDS WILL BE OF CONCERN. A FEW ISOLATED SVR WIND GUSTS MAY
ALSO OCCUR...PARTICULARLY IF LOCALIZED COLD POOLS AMALGAMATE AND
FOSTER MESO-BETA-SCALE ENHANCEMENTS TO THE LOW-LEVEL WIND THREAT.
THIS MAY BE BECOMING EVIDENT WITH ACTIVITY SPREADING SW OF THE WHITE
MOUNTAINS...THAT COULD AFFECT THE TUCSON AREA IN THE NEXT FEW HOURS.
THE EMX VWP SAMPLES 10-15-KT ELYS IN THE LOWEST 6 KM AGL...WHICH MAY
INDEED SUPPORT WWD MOVING COLD POOLS SPREADING ACROSS THE DESERT
FLOOR INTO THE LATE AFTERNOON/EARLY EVENING -- PERHAPS AFFECTING THE
PHOENIX AREA BY EARLY EVENING. HOWEVER...WITHOUT STRONGER DEEP SHEAR
IN PLACE...AND WITHOUT HIGHER CONFIDENCE IN UPSCALE CONVECTIVE
GROWTH...WW ISSUANCE IS PRESENTLY UNLIKELY...THOUGH TRENDS WILL BE
MONITORED THROUGH THE EVENING.

..COHEN/SCHNEIDER/HART.. 06/27/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...TWC...FGZ...PSR...

LAT...LON   31291107 32441213 34921207 34141044 33010919 31910905
            31270930 31291107

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 27, 4:53 PM MSTMesoscale DiscussionSPCMaricopa2 hr

Nearby

Mesoscale Discussions in Arizona, 2015Every mesoscale discussion in 2015

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.