Alert archive / Arizona / Mesoscale Discussions in 2003
Mesoscale Discussion 2154
The Storm Prediction Center issued this mesoscale discussion at Aug 14, 2003, 12:44 PM MST for 5 counties in Arizona. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 14, 2003, 12:44 PM MST (19:44 UTC)
- Expired
- Aug 14, 2003, 2:45 PM MST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
Counties Gila County, AZ, Graham County, AZ, Greenlee County, AZ, Maricopa County, AZ, Pinal County, AZ
The radar
The Phoenix radar (KIWA), 41 km from the middle of the area, began a volume at 19:45 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Phoenix, AZ (KPSR), launched 12:00Z, 7.7 hours before the alert went out and 45 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.
- Mixed-layer CAPE
- 668 J/kg
- Mixed-layer CIN
- -195 J/kg
- Mixed-layer LCL
- 1519 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 12 m²/s²
- 0-3 km storm-relative helicity
- 67 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
536 ACUS11 KWNS 141945 SWOMCD SPC MCD 141944 NMZ000-AZZ000-142145- MESOSCALE DISCUSSION 2154 NWS STORM PREDICTION CENTER NORMAN OK 0244 PM CDT THU AUG 14 2003 AREAS AFFECTED...CNTRL/SRN AZ CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 141944Z - 142145Z THE POTENTIAL FOR ISOLATED LARGE HAIL/DAMAGING WINDS WILL INCREASE THROUGH THE AFTERNOON AND EARLY EVENING HOURS. AREA WILL BE UPGRADED TO A SLIGHT RISK ON THE 20Z CONVECTIVE OUTLOOK AND CONDITIONS WILL BE MONITORED FOR A POSSIBLE WW LATER THIS AFTERNOON. AT 1925Z...REGIONAL RADAR MOSAIC AND VISIBLE SATELLITE IMAGERY SHOWED A CLUSTER OF TSTMS EXTENDING FROM CATRON COUNTY IN W-CNTRL NM WWD INTO GREENLEE AND SRN APACHE COUNTIES IN E-CNTRL AZ. ADDITIONAL TCU/SMALL CB DEVELOPMENT WAS ALSO NOTED FARTHER W ON THE RIM OVER SRN COCONINO COUNTY IN CNTRL AZ. STRONG DIABATIC HEATING HAS ALLOWED THE AIRMASS TO THE S OF THIS CONVECTIVE DEVELOPMENT TO BECOME SLIGHTLY TO MODERATELY UNSTABLE WITH MLCAPES OF 500-1500 J/KG. ADDITIONAL HEATING COUPLED WITH DYNAMIC COOLING/FORCING FOR ASCENT AHEAD OF MID-LEVEL TROUGH APPROACHING FROM THE E WILL CONTRIBUTE TO FURTHER DESTABILIZATION LATER THIS AFTERNOON INTO EVENING. AFOREMENTIONED TSTMS ARE EXPECTED TO INTENSIFY AS THEY MOVE SWWD INTO THIS AIRMASS...ESPECIALLY OVER S-CNTRL AZ WHERE THE GREATEST INSTABILITY EXISTS. RUC HODOGRAPHS AND REGIONAL VWP DATA INDICATE SUFFICIENT DEEP-LAYER SHEAR FOR ORGANIZED CONVECTION...INCLUDING THE POTENTIAL FOR SUPERCELLS. IN ADDITION TO DAMAGING OUTFLOW WINDS...LARGE HAIL WILL ALSO BE POSSIBLE...ESPECIALLY WITH ANY ROTATING UPDRAFTS. ..MEAD.. 08/14/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ABQ...EPZ...TWC...FGZ...PSR... 34591297 34681188 34431038 33720889 32390909 31891097 32661302 33841383
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 14, 1:45 PM MST | Severe Thunderstorm Watch | SPC | Gila, Maricopa, Pima, Pinal, Santa Cruz | 7 hr |
| Aug 14, 4:06 PM MST | Mesoscale Discussion | SPC | Apache, Cochise, Gila, Graham, Maricopa, Navajo and 3 more | 84 min |
Nearby
Mesoscale Discussions in Arizona, 2003Every mesoscale discussion in 2003
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.