.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 337 AM CDT THU SEP 10 2015 

LINGERING THUNDERSTORMS CONTINUED TO CLEAR OUT OF THE SOUTHERN PORTION OF THE CWA EARLY THIS MORNING. OTHERWISE...AN UPPER LEVEL SHORTWAVE TROUGH AND SURFACE COLD FRONT ARE EXPECTED TO IMPACT THE AREA BY EARLY THIS AFTERNOON AND INTO THE EVENING HOURS. THE NAM CONTINUES TO RAMP UP INSTABILITY...ANTICIPATING UP TO 4500 J/KG IN SOUTHEAST NEBRASKA...IN ADDITION TO 7+ C/KM MID LEVEL LAPSE RATES BY THURSDAY AFTERNOON AS WELL AS NEARLY 45 KTS OF BULK SHEAR. THE GFS REMAINS MORE MODEST/REASONABLE WITH APPROX 1500 J/KG AND 35-40 KTS OF SHEAR WHILE ALSO HINTING AT STEEPER LAPSE RATES. 

THE SOUTHERN HALF OF THE CWA REMAINS IN A MARGINAL RISK FOR SEVERE WEATHER... HOWEVER THE SOUTHERN TIER OF NEBRASKA COUNTIES HAS BEEN BUMPED UP TO A SLIGHT RISK. WHILE THE MOST FAVORABLE CONVECTIVE PARAMETERS WILL MOST LIKELY SET UP TO OUR SOUTH ACROSS CENTRAL KANSAS...A FEW DISCRETE SUPERCELLS COULD BE POSSIBLE IN SOUTHEAST NEBRASKA WHEN STORMS FIRST BEGIN TO INITIATE. LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN THREATS...WITH A BRIEF TORNADO OR TWO NOT ENTIRELY OUT OF THE QUESTION.

LOOKING TO THE FORECAST FOR THE DAYTIME HOURS TODAY AND THROUGH TONIGHT...
THE MAIN STORY LIES WITH ANOTHER ROUND OF THUNDERSTORM CHANCES... AND THE POTENTIAL FOR SEVERE WEATHER. MODELS ARE IN PRETTY GOOD AGREEMENT SHOWING YET ANOTHER SHORTWAVE DISTURBANCE ROTATING AROUND THE BASE OF THAT MAIN UPPER LEVEL LOW TO THE NORTH... AND SLIDING THROUGH THE NRN/CENTRAL PLAINS LATER TODAY/TONIGHT. THAT SFC BOUNDARY CURRENTLY JUST TO OUR NORTH WILL GET A BETTER PUSH SOUTH AS A COLD FRONT... WITH TIMING BETWEEN MODELS NOT HAVING A LOT OF VARIATION... SHOWING THE FRONT ALREADY NEAR THE NEB/KS STATE LINE AROUND MIDDAY... AND CLOSER TO I-70 IN NRN KS BY LATE AFTERNOON. THIS FRONT LOOKS TO PROVIDE THE FOCUS FOR ANOTHER ROUND OF THUNDERSTORMS... AND HAVE THE HIGHER POPS AFTER 20Z THIS AFTERNOON. THE HIGHEST POPS CONTINUE TO BE ACROSS THE SRN THIRD OR SO OF THE CWA...CLOSER TO THE MAIN SFC/LOWER LEVEL FRONTAL BOUNDARY. THINKING IS THAT OUR BEST CHANCES WILL RUN ROUGHLY THROUGH MID EVENING...WITH ACTIVITY SLIDING FURTHER SOUTH...AND DIMINISHING POPS WITH TIME REFLECT THAT. CONSIDERED DRYING THINGS OUT IN THE FINAL FEW HOURS OF THIS FORECAST PERIOD...BUT A FEW MODELS LINGER AT LEAST SOME ISOLATED ACTIVITY AROUND...SO KEPT SOME 20 POPS IN. MODELS SHOW THE POTENTIAL FOR AT LEAST MODEST AMOUNTS OF INSTABILITY DEVELOPING THROUGH THE AFTERNOON IN THE VICINITY OF THE SFC FRONT...AND DEEPER LAYER SHEAR IS SUFFICIENT FOR THE CONCERN FOR SEVERE WEATHER TO ARISE AGAIN TODAY. HAIL/WIND GUSTS WILL REMAIN THE PRIMARY CONCERN...BUT WITH THAT FRONT LINGERING ACROSS PORTIONS OF THE CWA LATER THIS AFTERNOON...AN ISOLATED TORNADO CANNOT BE RULED OUT.

.SHORT TERM...(TODAY THROUGH FRIDAY)
 ISSUED AT 339 AM CDT WED SEP 9 2015

 A BROAD UPPER LEVEL TROUGH WILL CONTINUE TO GRADUALLY SHIFT EAST OF THE REGION THROUGH THE PERIOD AS A LARGE RIDGE BUILDS IN OVER THE WEST COAST. A WEAK COLD FRONT WILL MAKE ITS WAY THROUGH THE REGION TODAY... BRINGING SHOWERS AND THUNDERSTORMS TO THE AREA THIS AFTERNOON AND INTO TONIGHT. WHILE BULK SHEAR VECTORS SHOULD RANGE FROM 35 TO 45 KTS ACROSS THE CWA THIS AFTERNOON...OVERALL INSTABILITY MAY BE LACKING. THE GFS DEPICTS LESS THAN 1000 J/KG OF CAPE DRAPED ACROSS THE REGION...WITH A STRONGER AXIS OF POTENTIAL ENERGY WELL OFF TO OUR WEST IN CENTRAL NEBRASKA. THE NAM IS MORE ROBUST WITH ANYWHERE FROM 1500 TO 3000 J/KG IN OUR AREA LATE THIS AFTERNOON AND EVENING...HOWEVER BELIEVE THIS MAY BE OVERDONE ONCE AGAIN. FOR NOW NORTHEAST NEBRASKA REMAINS IN A MARGINAL RISK FOR SEVERE STORMS WITH A SMALL CHANCE FOR LARGE HAIL AND GUSTY WINDS BEING THE MAIN THREATS. 


 SEVERE POTENTIAL THEN SHIFTS TO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA THURSDAY AFTERNOON AND EVENING AS THE FRONT SLOWLY MAKES ITS WAY SOUTH. THE NAM REALLY RAMPS UP INSTABILITY...ANTICIPATING UP TO 4500 J/KG IN SOUTHEAST NEBRASKA...IN ADDITION TO 8 C/KM MID LEVEL LAPSE RATES BY NOON THURSDAY. THE GFS REMAINS MORE MODEST/REASONABLE WITH 1500 TO 2000 J/KG WHILE ALSO HINTING AT STEEPER LAPSE RATES. THEREFORE EXPECT A FEW STRONG TO SEVERE STORMS COULD BE POSSIBLE LATE THURSDAY INTO FRIDAY...BEFORE PRECIP CHANCES DWINDLE BY FRIDAY MORNING.

Day 1 Severe Weather Outlook

Day 2 Severe Weather Outlook