583  
ACUS02 KWNS 151714  
SWODY2  
SPC AC 151713  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1213 PM CDT MON JUL 15 2019  
 
VALID 161200Z - 171200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE NORTHERN HIGH PLAINS...  
   
..SUMMARY
 
 
AT LEAST ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS THE  
NORTHERN HIGH PLAINS WITH A FEW STRONG STORMS POSSIBLE EXTENDING  
INTO THE UPPER MISSISSIPPI VALLEY. STRONG STORMS MAY ALSO OCCUR WITH  
THE REMNANTS OF BARRY.  
   
..SYNOPSIS
 
 
A SHORTWAVE TROUGH WILL MOVE ACROSS THE NORTHERN ROCKIES ON TUESDAY  
AND INTO THE HIGH PLAINS BY WEDNESDAY MORNING PROVIDING INCREASING  
WINDS ALOFT AND LIFT, MAINLY LATE IN THE PERIOD. AT THE SURFACE, A  
WEAK LEE TROUGH WILL DEVELOP FROM MT INTO WY, NE AND KS WHICH WILL  
MAINTAIN SOUTHEASTERLY SURFACE WINDS AND DEWPOINTS IN THE LOWER 60S  
F AS FAR WEST AS MT AND WY. AS A RESULT, STRONG INSTABILITY WILL  
DEVELOP FROM EASTERN MT AND WY EASTWARD ACROSS THE UPPER MS VALLEY,  
WITH THE MAIN FOCUS OVER THE NORTHERN HIGH PLAINS LATE TUESDAY  
AFTERNOON INTO THE EVENING IN ASSOCIATION WITH THE UPPER TROUGH.  
 
ELSEWHERE, THE REMNANTS OF BARRY WILL BRING PRECIPITATION TO PARTS  
OF THE MS VALLEY AND LOWER OH VALLEY, WHERE A FEW STRONG STORMS  
CANNOT BE RULED OUT.  
   
..NORTHERN HIGH PLAINS
 
 
MORNING STORMS OVER SD WILL CONTINUE EASTWARD DURING THE DAY,  
ALLOWING HEATING AND DESTABILIZATION TO OCCUR FROM WESTERN SD INTO  
SOUTHERN MT AND NORTHERN/EASTERN WY. HEATING AS WELL AS THE  
INFLUENCE OF THE SHORTWAVE TROUGH WILL ALLOW FOR STORM DEVELOPMENT  
BY 21Z FROM SOUTHWEST MT ACROSS NORTHERN AND EASTERN WY WHERE MOIST  
LOW-LEVEL WINDS WILL ALSO HAVE AN UPSLOPE COMPONENT. FORECAST  
SOUNDINGS SHOW RELATIVELY LONG, STRAIGHT HODOGRAPHS FAVORABLE FOR  
SPLITTING CELLS, WITH LARGE HAIL MOST LIKELY. A FEW SIGNIFICANT HAIL  
REPORTS ARE POSSIBLE. BY EVENING, STORMS WILL INCREASE OUTFLOW  
PRODUCTION WITH MERGERS SUPPORTING A DAMAGING WIND THREAT ACROSS THE  
MT/WY/SD/ND BORDER REGION. A TORNADO OR TWO IS POSSIBLE OVER THE  
SLIGHT RISK AREA PRIOR TO STORMS MERGING, AND WHEN THE LOW-LEVEL JET  
WILL BE INCREASING TO 30+ KT OUT OF THE SOUTHEAST.  
   
..UPPER MS VALLEY
 
 
MORNING STORMS ARE LIKELY TO BE ONGOING ACROSS SD, AND MOVING INTO  
MN DURING THE DAY, WITH STRONG WIND GUSTS POSSIBLE. THESE STORMS  
SHOULD CONTINUE TO INTERACT WITH AN UNSTABLE ENVIRONMENT EASTWARD  
THROUGH WI, SUPPORTING AREAS OF STRONG TO SEVERE WIND GUSTS. SHEAR  
PROFILES WILL BE WEAK, THUS ANY POTENTIALLY ORGANIZED THREAT WILL BE  
STORM SCALE, AND DIFFICULT TO ACCURATELY PREDICT AT THIS TIME.  
   
..AR TO THE LOWER OH VALLEY
 
 
THE REMNANTS OF BARRY WILL CONTINUE TO WEAKEN IN THE FORM OF A LOW  
MOVING ACROSS MO AND INTO IL, WITH A BAND OF 20 KT SOUTHWESTERLY  
MIDLEVEL WINDS EXTENDING FROM THE LOWER MS VALLEY ACROSS TN AND KY.  
DEWPOINTS WILL REMAIN IN THE 70S F ACROSS MOST OF THE REGION,  
CONTRIBUTING TO ONLY MARGINAL INSTABILITY AS TEMPERATURES ALOFT  
REMAIN WARM. AREAS OF RAIN AND STORMS WILL BE ONGOING FROM AR INTO  
SOUTHERN IL TUESDAY MORNING, WITH SOME INCREASE IN DIURNAL ACTIVITY  
EXPECTED. SOUTHERN PORTIONS OF THE AREA, FROM PORTIONS OF AR INTO  
MS, WILL BE MORE UNSTABLE, WITH GREATER BOUNDARY LAYER HEATING  
EXPECTED. THE MOIST AIR MASS COMBINED WITH PERHAPS 100-200 M2/S2  
EFFECTIVE SRH MAY SUPPORT A FEW BRIEFLY ROTATING STORMS, CAPABLE OF  
EITHER WIND GUST ENHANCEMENT OR A BRIEF/WEAK TORNADO.  
   
..MAXIMUM RISK BY HAZARD
 
 
TORNADO: 5% - SLIGHT  
WIND: 15% - SLIGHT  
HAIL: 15% SIG - SLIGHT  
 
..JEWELL.. 07/15/2019  
 

 
 
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