[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 041458
SWOMCD
SPC MCD 041455 
NMZ000-COZ000-AZZ000-UTZ000-041700-

MESOSCALE DISCUSSION 2160
NWS STORM PREDICTION CENTER NORMAN OK
0955 AM CDT SAT SEP 04 2004

AREAS AFFECTED...CNTRL AZ INTO THE FOUR CORNERS REGION

CONCERNING...CONVECTIVE TRENDS/SEVERE POTENTIAL 

VALID 041455Z - 041700Z

A FEW STRONG/ISOLATED SEVERE STORMS ARE POSSIBLE NEXT FEW HOURS...
BUT THREAT MAY REMAIN ISOLATED/BRIEF...AND NEED FOR WW IS NOT
CURRENTLY ANTICIPATED.

MOIST AIR MASS ACROSS THE SOUTHERN PLATEAU HAS BEEN SUPPORTIVE OF
VIGOROUS CONVECTIVE DEVELOPMENT IN ASSOCIATION WITH COLD UPPER
TROUGH.  WIDELY SCATTERED ACTIVITY IS ONGOING NORTHEAST OF PHOENIX
INTO THE IMMEDIATE FOUR CORNERS REGION.  VERTICAL SHEAR IN THE
VICINITY OF SOUTHWESTERLY 100 KT HIGH LEVEL JET IS PROVING FAVORABLE
FOR UPDRAFT ROTATION IN STRONGEST CELLS...EMBEDDED WITHIN
ENVIRONMENT WITH CAPE UP TO AROUND 1000 J/KG.

AIDED BY BREAKS IN CLOUD COVER...COVERAGE OF THUNDERSTORM ACTIVITY
LIKELY WILL INCREASE THROUGH MID DAY ACROSS A LARGE PORTION OF
EASTERN ARIZONA.  SOME HAIL WILL CONTINUE POSSIBLE ALONG WITH
INCREASING POTENTIAL FOR STRONG WIND GUSTS...PARTICULARLY IN WARMER/
MORE DEEPLY MIXED BOUNDARY LAYER SOUTH OF THE MOGOLLON RIM INTO
AREAS NORTH OF TUCSON.

HOWEVER...BY THE 18-20Z TIME FRAME...MODELS SUGGEST STRONGEST
MID-LEVEL FORCING FOR UPWARD VERTICAL MOTION WILL SHIFT INTO THE
CENTRAL ROCKIES...PERHAPS STILL TRAILING SOUTHWESTWARD INTO PARTS OF
NORTHEAST NEW MEXICO.  SUBSTANTIAL CLOUD COVER ACROSS THIS REGION
MAY LIMIT OVERALL DESTABILIZATION AND SEVERE THREAT DURING PEAK
HEATING HOURS...HOWEVER.  MEANWHILE...INCREASINGLY SUBSIDENT
MID-LEVEL REGIME IS EXPECTED TO SUPPRESS CONVECTIVE DEVELOPMENT
ACROSS MUCH OF ARIZONA...RESULTING IN WEAKENING/DIMINISHING
THUNDERSTORM ACTIVITY.

..KERR.. 09/04/2004

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

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

33541183 34721087 35401019 36810931 37550875 36700667
35410656 34080790 32840924 32361029 33091134 

WWWW