Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 290636
SWOMCD
SPC MCD 290636 COR
ILZ000-MOZ000-290900-

MESOSCALE DISCUSSION 1568
NWS STORM PREDICTION CENTER NORMAN OK
0136 AM CDT WED JUL 29 2015

AREAS AFFECTED...PORTIONS NERN MO...WRN IL.

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 290636Z - 290900Z

CORRECTED FOR TYPO IN HEADER

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...LINE OF TSTMS WITH INTERMITTENT/SMALL BOWING SEGMENTS WILL
OFFER LOCALIZED POTENTIAL FOR DAMAGING WINDS APCHG SVR LIMITS.
GIVEN LOW COVERAGE AND MRGL ORGANIZATION/MAGNITUDE OF RISK...WW IS
NOT ANTICIPATED ATTM.

DISCUSSION...LEADING EDGE AND STRONGEST SEGMENT OF STG TSTM BAND
EXTENDED AT 06Z FROM WRN SCHUYLER COUNTY MO SWWD TO NEAR CDJ.  FROM
THAT AREA WWD...CONVECTION WAS INCREASINGLY FAR BEHIND OUTFLOW
BOUNDARY THAT WAS PROCEEDING SEWD ACROSS NWRN MO AND SHOULD REMAIN
DECIDEDLY SUB-SVR.  NERN MO SEGMENT SHOULD CONTINUE TO HAVE CLOSEST
ACCESS TO FAVORABLE LOW-LEVEL MOISTURE/INSTABILITY...WITH MOISTURE
INCREASING EWD ACROSS MS RIVER.  MODIFIED FCST SOUNDINGS FOR
PROJECTED PATH ESEWD INTO WRN IL HAVE 1.6-2.1-INCH PW AND 16-19 G/KG
MEAN MIXING RATIOS...AND 00Z 850-MB CHART SHOWED 16.5-17.5 DEG C DEW
POINTS UPSTREAM.  THIS SUPPORTS MUCAPE ABOVE 3000 J/KG...AND MLCAPE
REMAINING IN 2000-2500 J/KG RANGE FOR A FEW MORE HOURS.  EFFECTIVE
INFLOW PARCELS APPEAR TO REMAIN SFC-BASED...ALBEIT INCLUDING
SHALLOW/COOL NEAR-SFC LAYER AND SBCINH INCREASING WITH TIME.

SFC DEW POINT AT IRK PLUMMETED 11 DEG F TO 65 IN AN HOUR FROM
04Z-05Z BEHIND WEAK OUTFLOW BOUNDARY FROM CONVECTION FARTHER
NE...AND ROSE ONLY A DEGREE BY 06Z.  HOWEVER...THAT OBSERVATION IS
SUSPECT GIVEN HIGHER/LITTLE-CHANGED POST-OUTFLOW DEW POINTS TO ITS
NE...AND LACK OF APPARENT HEATBURST/WARMING PROCESSES THAT ALSO
WOULD PERFORM DRYING.  THIS OB MAY RENDER LOW BIAS TO MOISTURE/CAPE
FIELDS IN OBJECTIVE ANALYSES....BUT OVERALL BUOYANCY AND CINH SHOULD
DECREASE GRADUALLY WITH TIME AMIDST NOCTURNAL/DIABATIC COOLING.
NEGATIVE FACTORS FOR UPSCALE ORGANIZATION/INTENSIFICATION BESIDES
CINH INCLUDE
1. WARMER AIR ALOFT AND DECREASING EFFECTIVE-SHEAR MAGNITUDES WITH
EWD EXTENT IN PROXIMITY TO UPPER RIDGE...AND
2. RELATIVELY WEAK/VEERED NATURE OF 850-MB FLOW -- I.E. ONLY 15-25
KT BASED ON REGIONAL VWP AND WLY...WHICH IS ALONG STORM-MOTION
VECTOR AND WHICH YIELDS LESS THAN 10 KT STORM-RELATIVE INFLOW.

LOCAL BOWING SEGMENTS MAY OFFER WEAKLY REAR-INFLOW-ASSISTED/
WATER-LOADED GUSTS APCHG SVR LEVELS...BUT OVERALL THREAT CURRENTLY
APPEARS TOO LIMITED FOR ANOTHER WW.  WW 459 EXPIRED AT 5Z ACROSS SRN
IA AND NRN MO...AND WAS NOT EXTENDED DUE TO MRGL/ISOLATED NATURE OF
SVR RISK.

..EDWARDS/BROYLES.. 07/29/2015

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

ATTN...WFO...ILX...LSX...DVN...EAX...

LAT...LON   39699346 39919300 40209280 40379277 40299152 40189044
            39429031 38909115 39519307 39699346



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