Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS03 KWNS 290724
SWODY3
SPC AC 290723

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0223 AM CDT WED JUL 29 2015

VALID 311200Z - 011200Z

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS THE CENTRAL PLAINS/UPPER
MIDWEST...

...SUMMARY...
A FEW STRONG STORMS WILL BE POSSIBLE ACROSS PARTS OF THE CENTRAL
PLAINS AND UPPER MIDWEST FRIDAY AFTERNOON AND EVENING.

...SYNOPSIS...
AN AMPLIFIED LARGE-SCALE PATTERN WILL EXIST OVER THE CONUS/ADJACENT
CANADA ON FRIDAY. BETWEEN AN UPPER RIDGE CENTERED OVER THE GREAT
BASIN/SOUTHERN ROCKIES...AND A LARGE-SCALE TROUGH OVER HUDSON
BAY/NORTHERN ONTARIO...A BELT OF RELATIVELY STRONG MID/HIGH-LEVEL
WEST-NORTHWESTERLY WINDS WILL EXTEND OVER THE UPPER MIDWEST/GREAT
LAKES AND NORTHEAST STATES.

...CENTRAL PLAINS/MIDDLE MO VALLEY/UPPER MIDWEST...
SOME GUIDANCE VARIABILITY EXISTS REGARDING THE TIMING/SPATIAL
DETAILS OF A WEAK SOUTHEASTWARD-MOVING FRONT ACROSS THE REGION.
PRE-FRONTAL MOISTENING WILL TEND TO BE LIMITED BY RESIDUAL
ANTICYCLONIC LOW-LEVEL TRAJECTORIES OVER THE LOWER MO
VALLEY/SOUTH-CENTRAL PLAINS...BUT A SPATIALLY NARROW CORRIDOR OF
MODEST MOISTENING WILL NONETHELESS OCCUR ACROSS PARTS OF THE REGION
AHEAD OF THE SOUTHEAST-ADVANCING FRONT. WHILE LARGER-SCALE FORCING
FOR ASCENT WILL BE WEAK...AMPLE HEATING/MIXING IN THE PRESENCE OF
WEAK NEAR-BOUNDARY CONVERGENCE SHOULD RESULT IN ISOLATED/WIDELY
SCATTERED THUNDERSTORM DEVELOPMENT FRIDAY AFTERNOON/EVENING. WHILE
CONFIDENCE IN SPATIAL/COVERAGE DETAILS ARE NOT PARTICULARLY
HIGH...LOW SEVERE PROBABILITIES APPEAR WARRANTED FOR AT LEAST A
CONDITIONAL-TYPE SEVERE RISK ACROSS THE REGION FRIDAY AFTERNOON INTO
EVENING. IF/WHERE DEEP CONVECTION DEVELOPS...SEVERE HAIL/WIND WOULD
BE THE MAIN POSSIBILITIES.

...SOUTHEAST STATES...
A FEW STRONGER STORMS CAPABLE OF DOWNBURSTS MAY BE POSSIBLE FRIDAY
AFTERNOON ACROSS THE COASTAL SOUTHEAST STATES/NORTH FL WITHIN A VERY
MOIST AIR MASS. HOWEVER...UNCERTAINTIES RELATED TO PRIOR DAY
CONVECTION/SUBSEQUENT CLOUD COVER...IN AN ENVIRONMENT OTHERWISE
CHARACTERIZED BY WEAK VERTICAL SHEAR/POOR MID-LEVEL LAPSE
RATES...PRECLUDE SEVERE PROBABILITIES AT THIS TIME.

..GUYER.. 07/29/2015



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