903  
FXUS63 KLBF 231126  
AFDLBF  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTH PLATTE NE  
626 AM CDT SAT OCT 23 2021  
   
UPDATE
 
 
ISSUED AT 434 AM CDT SAT OCT 23 2021  
 
PATCHY FOG DEVELOPING ACROSS NCNTL NEBRASKA WARRANTS A FORECAST  
UPDATE USING THE SREF WHICH ALSO SUGGESTS FOG WILL DEVELOP ACROSS  
PARTS OF WRN NEBRASKA EARLY THIS MORNING.  
 

 
   
SHORT TERM
 
(TODAY THROUGH SUNDAY)  
ISSUED AT 401 AM CDT SAT OCT 23 2021  
 
AN UPPER LEVEL DISTURBANCE AFFECTING NRN CALIFORNIA AND NEVADA THIS  
MORNING IS PROGGED TO MOVE THROUGH WRN AND NCNTL NEBRASKA TONIGHT  
AND SUNDAY. WPC CUT BACK ON QPF AMOUNTS BY ABOUT 50% AND LESS THAN  
1/4 INCH OF RAINFALL IS NOW EXPECTED AS THE SYSTEM MOVES THROUGH.  
HIGHEST AMOUNTS ARE EXPECTED ACROSS THE ERN EDGE OF NCNTL NEBRASKA.  
THIS IS LIKELY THE RESULT OF THE TRAJECTORY OF RETURN MOISTURE AND  
THE EVOLUTION OF THE FORCING WHICH FAVORS THE MISSOURI BASIN AND  
AREAS EAST ACROSS THE MIDWEST FOR THE BEST RAINFALL. FOR THESE  
REASONS, POPS ARE LIMITED TO 20 TO 50 PERCENT WITH THE HIGHER POPS  
ACROSS NCNTL NEBRASKA. THE ECM, RAP AND GFS KEEP WRN NEBRASKA DRY OR  
WITH JUST TRACE RAINFALL AMOUNTS WHILE THE NAM AND SREF ARE MUCH  
WETTER.  
 
THE TEMPERATURE FORECAST TODAY LEANS ON THE WARMER GFS GUIDANCE PLUS  
BIAS CORRECTION. THERE SHOULD STILL BE ENOUGH BREAKS IN THE CLOUD  
COVER TO SUPPORT A FORECAST NEAR THE 50TH PERCENTILE OF THE NBM.  
TONIGHT'S LOWS USE THE SHORT TERM MODEL BLEND PLUS BIAS CORRECTION  
AND ARE ON THE WARM SIDE OF THE FORECAST ENVELOPE. THIS IS BASED ON  
THE EXPECTED INCREASE IN CLOUD COVER WHICH WILL BLOCK ANY SORT OF  
RADIATIONAL COOLING. THE TEMPERATURE FORECAST SUNDAY IS SLIGHTLY  
COOLER THAN THE 50TH PERCENTILE OF THE NBM. ANY RAIN WHICH DEVELOPS  
WILL AFFECT TEMPERATURES NEGATIVELY.AN UPPER LEVEL DISTURBANCE  
AFFECTING NRN CALIFORNIA AND NEVADA THIS MORNING IS PROGGED TO  
MOVE THROUGH WRN AND NCNTL NEBRASKA TONIGHT AND SUNDAY. WPC CUT  
BACK ON QPF AMOUNTS BY ABOUT 50% AND LESS THAN 1/4 INCH OF  
RAINFALL IS NOW EXPECTED AS THE SYSTEM MOVES THROUGH. HIGHEST  
AMOUNTS ARE EXPECTED ACROSS THE ERN EDGE OF NCNTL NEBRASKA. THIS  
IS LIKELY THE RESULT OF THE TRAJECTORY OF RETURN MOISTURE AND THE  
EVOLUTION OF THE FORCING WHICH FAVORS THE MISSOURI BASIN AND AREAS  
EAST ACROSS THE MIDWEST FOR THE BEST RAINFALL. FOR THESE REASONS,  
POPS ARE LIMITED TO 20 TO 50 PERCENT WITH THE HIGHER POPS ACROSS  
NCNTL NEBRASKA. THE ECM, RAP AND GFS KEEP WRN NEBRASKA DRY OR WITH  
JUST TRACE RAINFALL AMOUNTS WHILE THE NAM AND SREF ARE MUCH  
WETTER.  
 
THE TEMPERATURE FORECAST TODAY LEANS ON THE WARMER GFS GUIDANCE PLUS  
BIAS CORRECTION. THERE SHOULD STILL BE ENOUGH BREAKS IN THE CLOUD  
COVER TO SUPPORT A FORECAST NEAR THE 50TH PERCENTILE OF THE NBM.  
TONIGHT'S LOWS USE THE SHORT TERM MODEL BLEND PLUS BIAS CORRECTION  
AND ARE ON THE WARM SIDE OF THE FORECAST ENVELOPE. THIS IS BASED ON  
THE EXPECTED INCREASE IN CLOUD COVER WHICH WILL BLOCK ANY SORT OF  
RADIATIONAL COOLING. THE TEMPERATURE FORECAST SUNDAY IS SLIGHTLY  
COOLER THAN THE 50TH PERCENTILE OF THE NBM. ANY RAIN WHICH DEVELOPS  
WILL AFFECT TEMPERATURES NEGATIVELY.  
   
LONG TERM
 
(SUNDAY NIGHT THROUGH FRIDAY)  
ISSUED AT 401 AM CDT SAT OCT 23 2021  
 
A PORTION OF THE ENERGY OPERATING WITHIN AN UPPER LEVEL LOW ACROSS  
THE GULF OF ALASKA WILL SWING SOUTH AND THROUGH THE WRN U.S.  
ARRIVING IN NEBRASKA TUESDAY NIGHT. THE MODELS ARE IN EXCELLENT  
AGREEMENT SHIFTING WINDS FROM SOUTH TO NORTH TUESDAY NIGHT OR  
EARLY WEDNESDAY MORNING. THE PASSAGE OF THIS FRONT IS THE BASIS  
FOR CHANCE TO LOW END LIKELY POPS TUESDAY NIGHT. GIVEN THE CALIBER  
OF THE MOISTURE RETURN- DEW POINTS IN THE 50S AND A SUBTROPICAL  
TAP STREAMING NORTH THROUGH OLD MEXICO AND TEXAS, CONFIDENCE IN  
1/4 INCH OR GREATER RAINFALL AMOUNTS ACROSS WRN AND NCNTL NEBRASKA  
IS MODERATE.  
 
A PERIOD OF STRONG WARM AIR ADVECTION JUXTAPOSED WITH RETURN MOISTURE  
ACROSS CNTL NEBRASKA TUESDAY NIGHT IS THE BASIS FOR THE RAINFALL  
FORECAST WHICH INCLUDES THUNDERSTORMS. 500MB HEIGHTS FALLS FROM A  
FAIRLY SHARP UPPER LEVEL TROF SHOULD STEEPEN LAPSE RATES  
SUFFICIENTLY FOR THUNDERSTORM DEVELOPMENT. SEVERE WEATHER PROCEDURES  
USING THE ECM AND GFS SUGGEST SCNTL OR EVEN SWRN NEBRASKA COULD BE  
AREAS OF INTEREST FOR STRONG OR SEVERE THUNDERSTORMS. FOR THIS  
REASON, SPC HAS OUTLOOKED PARTS OF SRN NEBRASKA FOR SEVERE WEATHER  
NEXT TUESDAY.  
 
THE MODELS SHOW THIS STORM SYSTEM DEEPENING ACROSS THE MIDSOUTH  
WEDNESDAY AND THURSDAY. CONFIDENCE IS HIGH FOR STRONG WINDS ACROSS  
WRN AND NCNTL NEBRASKA WEDNESDAY AND THURSDAY. H850-700MB WINDS ARE  
30-50KTS BOTH DAYS BACKED BY 500M AGL WINDS OF 20 TO 30+KTS. IF THE  
MODELS ARE CORRECT, SUSTAINED 20 TO 30 MPH WINDS SHOULD DEVELOP  
ACROSS THE REGION BOTH DAYS.  
 

 
   
AVIATION
 
(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)  
ISSUED AT 620 AM CDT SAT OCT 23 2021  
 
PATCHY FOG WILL CONTINUE TO LEAD TO LOCALLY IFR/LIFR CONDITIONS  
ACROSS THE SANDHILLS AND NORTH CENTRAL NEBRASKA FOR A FEW MORE  
HOURS THIS MORNING BEFORE DIMINISHING. LOW STRATUS EXPANDS THIS  
EVENING AND WILL LEAD TO MVFR/LOCALLY IFR CIGS FOR TERMINALS  
GENERALLY EAST OF A SNY TO GRN LINE. SOME PRECIPITATION WILL  
DEVELOP OVERNIGHT THOUGH CONFIDENCE REMAINS LOW FOR INCLUSION AT  
LBF/VTN AT THIS TIME. WINDS REMAIN BREEZY FROM THE SOUTH THIS  
AFTERNOON, WITH GUSTS AROUND 15 TO 20KTS ANTICIPATED.  
 

 
   
LBF WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
UPDATE...CDC  
SHORT TERM...CDC  
LONG TERM...CDC  
AVIATION...BROWN  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab NE Page Main Text Page