Alert archive / Arizona / Mesoscale Discussions in 2012

Mesoscale Discussion 764

May 9, 20127 counties in Arizona; 4 counties in New Mexico

The Storm Prediction Center issued this mesoscale discussion at May 9, 2012, 9:56 AM MST for 7 counties in Arizona; 4 counties in New Mexico. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 9, 2012, 9:56 AM MST (16:56 UTC)
Expired: May 9, 2012, 12:00 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, Greenlee County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ, Doña Ana County, NM, Grant County, NM, Hidalgo County, NM, Luna County, NM

The radar

The Tucson radar (KEMX), 105 km from the middle of the area, began a volume at 16:55 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 12:00Z, 4.9 hours before the alert went out and 120 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 156 J/kg
Mixed-layer CIN: -387 J/kg
Mixed-layer LCL: 2533 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 42 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.

138 
ACUS11 KWNS 091656
SWOMCD
SPC MCD 091656 
TXZ000-NMZ000-AZZ000-091900-

MESOSCALE DISCUSSION 0764
NWS STORM PREDICTION CENTER NORMAN OK
1156 AM CDT WED MAY 09 2012

AREAS AFFECTED...SERN AZ...SWRN NM

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 091656Z - 091900Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...SCATTERED THUNDERSTORMS WILL PRODUCE STRONG TO POTENTIALLY
DAMAGING WIND GUSTS INTO THIS AFTERNOON/EARLY EVENING. THE STRONGEST
STORMS THIS AFTERNOON WILL ALSO POSE A MARGINALLY SEVERE HAIL
THREAT.

DISCUSSION...THUNDERSTORMS CONTINUE TO INCREASE IN COVERAGE AND
INTENSITY WITH DIURNAL HEATING IN ADVANCE OF UPPER LOW OVER NWRN
MEXICO. LARGE TEMP-DEW POINT SPREADS WILL DEVELOP BY EARLY AFTERNOON
PROMOTING AN INCREASED THREAT OF STG/DAMAGING WIND GUSTS WITH THE
STRONGER STORMS.  STEEP LAPSE RATES COMBINED WITH COOL TEMPERATURES
ALOFT WILL ALSO RESULT IN A MARGINAL HAIL THREAT THIS AFTERNOON AS
INSTABILITY INCREASES TO AROUND 1000 J/KG.  WHILE A WATCH IS NOT
ANTICIPATED IN THE SHORT TERM CONVECTIVE TRENDS WILL CONTINUE TO BE
MONITORED.

..BUNTING/MEAD/LEITMAN.. 05/09/2012

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

ATTN...WFO...ABQ...EPZ...TWC...FGZ...PSR...

LAT...LON   31300942 31321109 31821264 32431299 33421245 33851155
            33860985 33440868 32960729 32030649 31780654 31750824
            31300822 31300942

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 8, 5:34 PM MST	Mesoscale Discussion	SPC	Doña Ana, Otero	56 min

Nearby

Mesoscale Discussions in Arizona, 2012 Mesoscale Discussions in New Mexico, 2012 Every mesoscale discussion in 2012

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.