619  
FXUS63 KLBF 170905  
AFDLBF  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTH PLATTE NE  
405 AM CDT MON JUN 17 2024  
   
KEY MESSAGES
 
 
- LINGERING THUNDERSTORMS EARLY THIS MORNING WILL CONTINUE TO  
POSE A RISK OF LOCALLY HEAVY RAINFALL ACROSS NORTHERN  
NEBRASKA, BEFORE EXITING THE AREA BY EARLY THIS AFTERNOON.  
 
- REDEVELOPMENT OF ISOLATED TO WIDELY SCATTERED THUNDERSTORMS  
THIS AFTERNOON AND EVENING WILL LEAD TO AN INCREASING THREAT  
FOR SEVERE WEATHER, WITH VERY LARGE HAIL, DAMAGING WINDS, AND  
A TORNADO OR TWO POSSIBLE.  
 
- ADDITIONAL ROUNDS OF THUNDERSTORMS WILL PERSIST NEARLY EACH  
DAY INTO THE END OF THE WEEK, WITH AT LEAST SOME CONTINUING  
THREAT FOR STRONG TO SEVERE THUNDERSTORMS BY LATE WEEK.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 404 AM CDT MON JUN 17 2024  
 
CURRENTLY, AN ONGOING MCS CONTINUES TO MOVE EASTWARD ACROSS THE  
SANDHILLS, WITH AN EAST TO WEST ORIENTED BAND OF ROBUST CONVECTION  
CENTERED NORTH OF HWY 20 IN KEYA PAHA AND BOYD COUNTIES. THIS LINE  
HAS PRIMARILY BROUGHT LOCALLY HEAVY RAINFALL, THOUGH MULTIPLE GUSTS  
OF AROUND 40 TO 45 MILES PER HOUR HAVE BEEN OBSERVED AS WELL. THIS  
LINE AND ITS ASSOCIATED OUTFLOW WILL CONTINUE TO PUSH EAST EARLY  
THIS MORNING, GRADUALLY EXITING THE AREA THROUGH LATE MORNING.  
 
ATTENTION THEN TURNS TO A ROUND OF POTENTIALLY SIGNIFICANT SEVERE  
WEATHER ACROSS MUCH OF WESTERN AND NORTH CENTRAL NEBRASKA TONIGHT.  
FOR THE NEAR TERM, WILL HAVE TO WATCH THE PROGRESSION OF THE OUTFLOW  
FROM THIS MORNING'S STORMS, CURRENTLY STRETCHING FROM CENTRAL INTO  
PORTIONS OF SOUTHWEST NEBRASKA. IT IS UNCERTAIN HOW THIS OUTFLOW  
WILL IMPACT THE PROGRESSION OF A FRONTAL BOUNDARY, CURRENTLY  
BISECTING FROM JUST SOUTH OF IML TO SOUTH OF OFK, AS IT SLOWLY LIFTS  
NORTHWARD THIS AFTERNOON. GIVEN THE STRONG WARM ADVECTION ACROSS THE  
BROAD WARM SECTOR IN SOUTH CENTRAL NEBRASKA, NOT ANTICIPATING THE  
OUTFLOW BOUNDARY TO DAMPEN THE FRONT SOUTHWARD MUCH THIS MORNING.  
ALOFT, SOUTHWESTERLY FLOW PREVAILS, WITH AN UPPER LOW ANTICIPATED TO  
SLIDE EASTWARD INTO THE INTERMOUNTAIN WEST INTO THIS EVENING. BROAD  
POSITIVE VORTICITY ADVECTION AND SUBTLE HEIGHT FALLS ARE EXPECTED TO  
OVERSPREAD THE AREA THROUGH THE DAY TODAY, WITH NOTHING IN THE WAY  
OF A MORE OBVIOUS SHORTWAVE TROUGH UPSTREAM. AT THE SURFACE, BROAD  
LEE CYCLOGENESIS WILL PERSIST INTO THIS AFTERNOON ACROSS EASTERN  
COLORADO, WITH THE SURFACE LOW EXPECTED TO GRADUALLY EJECT  
NORTHEASTWARD TOWARDS SOUTHWEST NEBRASKA BY TONIGHT. IN RESPONSE TO  
THE INCREASING SURFACE CYCLOGENESIS, INCREASING PRESSURE FALLS AND  
STRENGTHENING WARM ADVECTION SHOULD PROMOTE THE AFOREMENTIONED  
SURFACE FRONT TO LIFT NORTHWARD TOWARDS THE SANDHILLS INTO THIS  
AFTERNOON. ALONG AND SOUTH OF THIS BOUNDARY, DEWPOINTS IN THE UPPER  
60S TO LOW 70S ARE ANTICIPATED, ALONG WITH SURFACE TEMPERATURES  
WARMING INTO THE 90S. LAPSE RATES ALOFT WILL REMAIN VERY STEEP, AND  
IN COMBINATION WITH THE WARM/MOIST BOUNDARY LAYER WILL SEND MLCAPE  
TO ABOVE 3000J/KG FOR AREAS SOUTH OF THE FRONTAL BOUNDARY. MOISTURE  
POOLING NEAR THE BOUNDARY MAY PROMOTE LOCALLY HIGHER INSTABILITY AS  
WELL. AS TEMPERATURES WARM THIS AFTERNOON, RESIDUAL CIN SHOULD ERODE  
ACROSS THE WARM SECTOR, WITH FORECAST SOUNDINGS SUGGESTING A LARGELY  
UNCAPPED ENVIRONMENT BY LATE AFTERNOON. THAT SAID, A LACK OF  
UPPER LEVEL SUPPORT SHOULD LIMIT ROBUST CONVECTIVE INITIATION TO  
LOCALLY ENHANCED CONVERGENCE NEAR THE AFOREMENTIONED SURFACE  
BOUNDARY AND POTENTIALLY JUST AHEAD OF THE NORTHEASTWARD LIFTING  
SURFACE LOW IN NORTHEAST COLORADO. THIS SHOULD LEAD TO ISOLATED  
TO WIDELY SCATTERED CONVECTIVE DEVELOPMENT THIS AFTERNOON  
ACROSS THE AREA, IN CLOSER PROXIMITY TO SURFACE BOUNDARIES.  
INITIAL UPDRAFTS MAY STRUGGLE OWING TO DRY LFC-LCL RELATIVE  
HUMIDITY, AND MULTIPLE CI ATTEMPTS MAY BE NEEDED FOR AN UPDRAFT  
TO EVENTUALLY BECOME DOMINANT. THIS WILL BE AIDED WHERE TCU CAN  
CLUSTER AND BETTER SHIELD THEMSELVES FROM DRY AIR ENTRAINMENT,  
LIKELY AGAIN NEAR THE SURFACE FRONT. MESOSCALE DETAILS WILL  
DRIVE THE ZONE OF GREATEST THREAT TODAY, AND BOUNDARY  
PROGRESSION WILL NEED TO BE MONITORED CLOSELY. GUIDANCE  
CURRENTLY PAINTS THIS FRONT REACHING SOMEWHERE NEAR THE HWY 2 TO  
HWY 20 CORRIDOR BY LATE THIS EVENING, THOUGH WILL AT LEAST  
MENTION THERE HAS BEEN A GRADUAL SOUTHWARD TREND NOTED IN HIGH-  
RES SOLUTIONS OVER THE LAST 12-24HRS.  
 
SHOULD ROBUST CI OCCUR, THE ENVIRONMENT WILL BE VERY SUPPORTIVE OF  
ROTATING UPDRAFTS, WITH FORECAST SOUNDINGS INDICATING NEAR PURE  
STREAMWISE VORTICITY IN THE LOWEST FEW KILOMETERS OF THE HODOGRAPH  
BY LATE EVENING. THIS IS IN COMBINATION OF STRENGTHENING BACKED  
SOUTHEASTERLY SURFACE WINDS (PRIMARILY IN CLOSER PROXIMITY TO THE  
SURFACE FRONT) AND AN INCREASING SOUTHERLY LLJ (H85 FLOW ~40-50KTS)  
THAT SHOULD OVERSPREAD THE PLAINS NEAR/AFTER SUNSET. BROAD  
SOUTHWESTERLY FLOW IN THE MID-LEVELS WILL LENGTHEN HODOGRAPHS WITH  
HEIGHT SOMEWHAT AS WELL. THIS POINTS TOWARDS A CORRIDOR OF ALL  
SEVERE HAZARDS SHOULD ROBUST SUPERCELLULAR DEVELOPMENT OCCUR  
THIS EVENING NEAR THE SURFACE FRONT. ANY TORNADO THREAT WILL  
LIKELY BE MAXIMIZED NEAR THE FRONT SHOULD A STORM ANCHOR  
NEARBY. INSTANCES OF LARGE TO VERY LARGE HAIL WILL LIKELY  
ACCOMPANY ANY DOMINANT SUPERCELLS AS WELL, BOTH NEAR THE FRONT  
AND FURTHER SOUTH. IT APPEARS THERE WILL BE AT LEAST A SHORT  
WINDOW WHERE STORMS COULD MAXIMIZE A ROBUST SEVERE WEATHER  
THREAT, BEFORE CIN QUICKLY INCREASES AGAIN NEAR/AFTER SUNSET AND  
UPDRAFTS WILL HAVE A PROPENSITY TO BECOME QUICKLY ELEVATED. THE  
BETTER SIGNAL FOR CI WITH RESPECT TO HIGH-RES GUIDANCE IS  
ACROSS FAR NORTHEAST CO AHEAD OF THE SURFACE LOW, WITH THIS  
CONVECTION LIFTING INTO SOUTHWEST NE AND PRESENTING A THREAT FOR  
LARGE HAIL/DAMAGING WINDS. LESSER SIGNAL EXISTS FOR ROBUST CI  
ALONG THE SURFACE FRONT. WITH LARGELY SUBTLE FORCING, MESOSCALE  
DETAILS WILL DRIVE THE DIFFERENCE BETWEEN JUST SOME CUMULUS  
DEVELOPMENT AND ROBUST SUPERCELLS. THIS WILL CONTINUE TO BE  
MONITORED VERY CLOSELY, AND FUTURE FORECASTS SHOULD BE MONITORED  
CLOSELY.  
 
CONVECTION WILL LARGELY WEAKEN AFTER SUNSET AND EXIT THE AREA PRIOR  
TO MIDNIGHT. THE DEEPENING SURFACE LOW WILL KEEP WARM ADVECTION  
STRONG, AND SHOULD PROMOTE INCREASING SYNOPTIC WINDS OVERNIGHT. IN  
FACT, SOME HIGH-RES GUIDANCE PAINTS SOUTHERLY WIND GUSTS EVEN AS  
HIGH AS GREATER THAN 50MPH OVERNIGHT. THIS IS LARGELY DUE TO ENOUGH  
MECHANICAL MIXING TO TAP INTO THE STRONGER SOUTHERLIES ALOFT, AND  
CONFIDENCE IN THIS IS NOT HIGH FOR NOW. STILL, A PERIOD OF 40-45MPH  
GUSTS LOOK LIKELY TONIGHT, AND SHOULD KEEP TEMPERATURES VERY MILD IN  
THE UPPER 60S TO LOW 70S ACROSS SOUTHWEST AND CENTRAL NEBRASKA,  
WHERE THEY WILL REMAIN SOUTH OF THE FRONT. THE BOUNDARY LAYER LOOKS  
TO DECOUPLE TO THE NORTH OF THE FRONT, LEADING TO LOWS IN THE UPPER  
50S TO LOW 60S ACROSS NORTHWEST NEBRASKA.  
 

 
   
LONG TERM /TUESDAY THROUGH SUNDAY/
 
 
ISSUED AT 404 AM CDT MON JUN 17 2024  
 
A SURFACE COLD FRONT WILL QUICKLY PUSH THROUGH THE AREA TUESDAY  
MORNING, AS THE AFOREMENTIONED SURFACE LOW EJECTS INTO EASTERN  
SD. THIS FRONT LARGELY LOOKS TO CLEAR THE AREA BY TOMORROW  
AFTERNOON, KEEPING A RENEWED ROUND OF CONVECTION OFF TO THE  
EAST. STILL, AT LEAST SOME GUIDANCE SUGGESTS THE FRONTAL  
BOUNDARY IS SLOW ENOUGH TO KEEP A THREAT FOR SCATTERED  
THUNDERSTORMS ACROSS FAR EASTERN CUSTER AND WHEELER COUNTIES.  
CONFIDENCE IN THE TIMING OF THE FRONT REMAINS LOWERED, AND WILL  
BE MONITORED GOING FORWARD. A THREAT FOR LARGE HAIL AND DAMAGING  
WINDS WOULD ACCOMPANY STORMS SHOULD THE FRONT SLOW ENOUGH TO  
IMPACT MORE OF CENTRAL AND NORTH CENTRAL NEBRASKA.  
 
THE AREA REMAINS POST-FRONTAL ON WEDNESDAY AND INCREASED COLD  
ADVECTION BEHIND THE BOUNDARY SHOULD LEAD TO A DAY OF WELL BELOW  
AVERAGE TEMPERATURES IN THE UPPER 60S TO LOW 70S. THE RETURN OF  
SOUTHERLY FLOW LATE THIS WEEK SHOULD BRING WITH IT RETURNING  
THUNDERSTORM CHANCES, AND THESE LOOK TO PERSIST INTO THE WEEKEND.  
ALOFT WEST-SOUTHWEST FLOW LATE WEEK GIVES WAY TO NORTHWESTERLY FLOW  
THIS WEEKEND, AND AT LEAST SOME THREAT FOR SEVERE WEATHER SHOULD  
RETURN INTO THIS WEEKEND.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
 
 
ISSUED AT 1250 AM CDT MON JUN 17 2024  
 
NEAR TERM TAFS WILL BE DEALING WITH TIMING OF ONGOING  
THUNDERSTORMS AS THEY MOVE EASTWARD ACROSS CENTRAL NEBRASKA  
EARLY TONIGHT. WITH UPSTREAM CONVECTION EXPECTED TO TRAIN OVER  
KVTN WILL GO WITH IFR VSBY AND PREVAILING +TSRA FOR THE NEXT 2  
HOURS, AND WILL ALSO MENTION SOME HAIL. HOWEVER THERE HAS NOT  
BEEN MUCH IN THE WAY OF ANY INDICATION FOR CONVECTIVE WINDS  
UPSTREAM FROM KVTN SO WILL NOT MENTION ANY ENHANCED WINDS THERE  
BUT WILL MONITOR CLOSELY. MUCH OF THE CONVECTION MOVING EAST OF  
HIGHWAY 61 IS EXPECTED TO SLIDE JUST NORTH OF KLBF BUT WILL USE  
A ONE HOUR TEMPO FOR THUNDER THERE TO HANDLE THE PASSAGE.  
 
WITH A FRONT DRAPED ACROSS THE REGION, EXPECT IFR CIGS WILL  
REMAIN JUST NORTH OF KLBF ONCE THE THUNDERSTORMS PUSH OFF TO THE  
EAST, BUT KVTN WILL SEE IFR CONDITIONS WITH ANY IMPROVEMENT TO  
MVFR HOLDING OFF UNTIL AFTER DAYBREAK. EXPECT VFR AT KLBF AND  
MVFR AT KVTN WILL PERSIST THORUGH THE DAY ON MONDAY UNTIL  
ANOTHER ROUND OF THUNDERSTORMS DEVELOPS TOWARD 00Z AND PERSIST  
THROUGH THE END OF THE VALID PERIOD.  
 
OUTSIDE OF CONVECTION, WINDS WILL GENERALLY BE 10KT OR LESS WITH  
LOW LEVEL WIND SHEAR PERSISTING UNTIL A BIT AFTER DAYBREAK. KLBF  
WILL SEE SOME GUSTS AT OR ABOVE 25KT DEVELOP LATER MONDAY  
MORNING AS THE LOW LEVEL WIND FIELD STARTS TO ENHANCE WITH AN  
INCREASE TO AT OR ABOVE 30KT TOWARD THE LATTER PORTION OF THE  
VALID PERIOD. KVTN WILL BE ON THE COOL SIDE OF THE FRONT,  
KEEPING GUSTS IN CHECK THROUGH LOW LEVEL WIND SHEAR WILL BE  
PREVALENT.  
 

 
   
LBF WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
SHORT TERM...BROWN  
LONG TERM...BROWN  
AVIATION...MBS  
 
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