Severe Storm Outlook Narrative (AC)
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6
000
ACUS03 KWNS 230647
SWODY3
SPC AC 230646

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0146 AM CDT SAT JUL 23 2016

VALID 251200Z - 261200Z

...THERE IS A MRGL RISK OF SVR TSTMS IN THE NORTHEAST...

...THERE IS A MRGL RISK OF SVR TSTMS SWRN ND TO NERN CO...

...SUMMARY...
ISOLATED SEVERE STORMS ARE EXPECTED ACROSS THE NORTHEAST AND THE
NORTHERN GREAT PLAINS TO CENTRAL HIGH PLAINS...MAINLY MONDAY
AFTERNOON AND EVENING.

...SYNOPSIS...
A SHORTWAVE TROUGH WILL EJECT FROM NORTHEAST ONTARIO ACROSS
QUEBEC...WITH CONSENSUS OF GUIDANCE SUGGESTING ASSOCIATED MID-LEVEL
HEIGHTS SOMEWHAT DAMPENING IN AMPLITUDE DURING THE PERIOD. THIS
SHOULD RESULT IN FRONTOLYSIS OF THE ATTENDANT TRAILING COLD FRONT
EXPECTED TO BE OVER THE LOWER GREAT LAKES TO MIDWEST AT 12Z/MON.

...NORTHEAST...
SCATTERED CONVECTION MAY BE ONGOING AT 12Z/MONDAY ALONG/AHEAD OF THE
COLD FRONT WITHIN A PERSISTENT WARM CONVEYOR FROM THE MIDWEST INTO
NY. THIS SHOULD HINDER DIURNAL DESTABILIZATION IN SOME AREAS...WITH
MORE ROBUST DIABATIC HEATING LIKELY OCCURRING TO THE SOUTH OF
MORNING ACTIVITY OVER THE OH VALLEY. AMID WEAK MID-LEVEL HEIGHT
FALLS...GUIDANCE IS CONSISTENT IN DEPICTING SCATTERED PRE-FRONTAL
CONVECTION DEVELOPING THROUGH THE AFTERNOON. MODERATE DEEP SHEAR
SHOULD LARGELY REMAIN CONFINED TO LESS-UNSTABLE AREAS TO THE
NORTH...WITH WEAKER SHEAR BUT GREATER BUOYANCY SOUTH.

THIS SETUP SHOULD SUPPORT A BROAD AREA OF STRONG TO MARGINALLY
SEVERE STORMS PRODUCING POCKETS OF WIND DAMAGE MONDAY AFTERNOON INTO
EARLY EVENING. CONTINUED DIFFERENCES IN GUIDANCE WITH BOTH THE
STRENGTH/PLACEMENT OF ENHANCED 700-500 MB WESTERLIES...ALONG WITH
THE FRONTOLYTIC NATURE OF THE COLD FRONT AND UNCERTAINTY OVER THE
NORTHERN/EASTERN EXTENT OF GREATER THAN WEAK BUOYANCY RENDER LOW
CONFIDENCE IN HIGHLIGHTING A SLIGHT RISK THIS OUTLOOK.

...SOUTHWEST ND TO NORTHEAST CO...
A BELT OF CONFLUENT MID/UPPER-LEVEL WESTERLIES SHOULD BE PRESENT
NORTH OF AN UPPER HIGH CENTERED OVER THE SOUTHERN HIGH PLAINS.
LOW-LEVEL FLOW SHOULD BE PREDOMINANTLY SOUTHEAST...YIELDING UPSLOPE
INTO THE BLACK HILLS AND PARTS OF THE FRONT RANGE AMID AN
INCREASINGLY MOIST BOUNDARY LAYER OVER THE ADJACENT PLAINS. ISOLATED
LATE-DAY STORMS SHOULD FORM NEAR THE HIGHER TERRAIN WITHIN STEEP
TROPOSPHERIC LAPSE RATES. SUFFICIENT DEEP SHEAR WILL EXIST FOR A
COUPLE SUPERCELLS...BUT CONFIDENCE IN GREATER THAN ISOLATED STORMS
IS BELOW-AVERAGE FOR THIS TIME FRAME. THUS...WILL DEFER TO LATER
OUTLOOKS ON POSSIBLE SLIGHT RISK DELINEATION.

..GRAMS.. 07/23/2016

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.