[MCD] SWOMCD

Mon Jul 17 22:02:44 UTC 2006

ACUS11 KWNS 172201
SWOMCD
SPC MCD 172201 
MIZ000-172300-

MESOSCALE DISCUSSION 1539
NWS STORM PREDICTION CENTER NORMAN OK
0501 PM CDT MON JUL 17 2006

AREAS AFFECTED...SRN/ERN LWR MI

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 172201Z - 172300Z

NEW WW WILL PROBABLY BE ISSUED TO THE SOUTHEAST OF WW 607 SHORTLY.

STRONGEST FORCING ASSOCIATED WITH SHORT WAVE TROUGH SHIFTING ACROSS
ONTARIO AND THE UPPER GREAT LAKES REGION NOW SEEMS WELL TO THE EAST
NORTHEAST OF LOWER MICHIGAN...ACROSS PARTS OF SOUTHERN ONTARIO AND
WESTERN QUEBEC.  HOWEVER...WEAKENED INHIBITION ASSOCIATED WITH
MID-LEVEL COOLING...NEAR FRONTAL ZONE ADVANCING SOUTHWARD INTO
NORTHERN LOWER MICHIGAN...HAS BEEN SUFFICIENT TO SUPPORT DEVELOPING
LINE OF INTENSE STORMS.  FOCUS APPEARS TO BE PRE-FRONTAL THERMAL
RIDGE AXIS...WHERE STEEP LAPSE RATES EXIST...CONTRIBUTING TO MIXED
LAYER CAPE ON THE ORDER OF 3000 J/KG.  

UNCERTAINTY EXISTS CONCERNING LONGEVITY OF SMALL CLUSTER OF
STORMS...NOW NORTH OF GRAND RAPIDS...WHICH COULD APPROACH AREAS
WEST/NORTHWEST OF DETROIT BY 00Z.  ACTIVITY COULD WEAKEN AS IT
PROGRESS TO THE SOUTH/EAST OF NARROW INSTABILITY AXIS. 
REGARDLESS...AS SURFACE FRONT DEVELOPS SOUTHWARD THIS
EVENING...LOW-LEVEL FORCING/DESTABILIZATION PROBABLY WILL BE
SUFFICIENT TO SUPPORT INCREASING SEVERE THREAT ACROSS THE FLINT/
LANSING AND DETROIT AREAS BY AT LEAST 03Z.

..KERR.. 07/17/2006

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

ATTN...WFO...DTX...GRR...

42268298 42068381 42138520 42268575 42798580 43438530
43778410 44058312 

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