677  
FXUS63 KLBF 212332  
AFDLBF  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTH PLATTE NE  
532 PM CST FRI FEB 21 2020  
   
SYNOPSIS
 
 
ISSUED AT 328 PM CST FRI FEB 21 2020  
 
H5 ANALYSIS THIS MORNING HAS A TROUGH OF LOW PRESSURE  
EXTENDING FROM NEWFOUNDLAND CANADA SOUTHWEST INTO NORTHERN ALABAMA.  
FURTHER WEST, A LOW AMPLITUDE RIDGE EXTENDED FROM NORTHERN NEW  
MEXICO NORTHWEST INTO SOUTHERN IDAHO. FURTHER WEST OF THIS FEATURE,  
A CLOSED LOW WAS LOCATED ROUGHLY 500 MILES WEST OF LOS ANGELES  
CALIFORNIA. THIS FEATURE SHOWS UP NICELY ON WV IMAGERY THIS  
AFTERNOON. A LARGE PLUME OF PACIFIC MOISTURE WAS SOUTH OF THIS  
FEATURE, AND EXTENDED NORTHEAST INTO THE SWRN CONUS. AT THE SURFACE,  
HIGH PRESSURE WAS ANCHORED OVER THE ARKLATEX INTO THE TENNESSEE  
VALLEY. NORTH OF THIS FEATURE, A SURFACE TROUGH OF LOW PRESSURE  
EXTENDED FROM EASTERN NORTH DAKOTA INTO CENTRAL NEBRASKA. ACROSS  
WESTERN AND NORTH CENTRAL NEBRASKA, VISIBLE SATELLITE IMAGERY HAS A  
BROAD AREA OF SNOW COVER EXTENDING FROM GARDEN COUNTY INTO THE  
SANDHILLS, EAST NORTHEAST INTO HOLT COUNTY. SKIES WERE CLEAR THIS  
AFTERNOON AND TEMPERATURES AS OF 2 PM CST RANGED FROM 41 IN O'NEILL  
TO 59 AT VALENTINE.  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH SATURDAY NIGHT)  
ISSUED AT 328 PM CST FRI FEB 21 2020  
 
THE MAIN FORECAST CHALLENGES IN  
THE NEAR TERM ARE TEMPERATURES AND WIND. ANOTHER TRICKY ELEMENT IN  
THE FORECAST OVER THE NEXT 24 HOURS IS SOME FIRE WEATHER CONCERNS IN  
THE FAR SOUTHWESTERN FORECAST AREA SATURDAY AFTERNOON. FOR TONIGHT,  
SKIES WILL REMAIN MOSTLY CLEAR WITH THE EXCEPTION OF SOME HIGH  
CLOUDS ACROSS NORTHERN NEBRASKA. THIS IS IN ADVANCE OF A VERY WEAK  
SHORTWAVE WHICH ENTERS THE WESTERN DAKOTAS EARLY SATURDAY MORNING.  
LOWS WILL RANGE FROM THE UPPER TEENS TO LOWER 20S. THE BEFORE  
MENTIONED TROUGH WILL FORCE A SURFACE TROUGH THROUGH THE FORECAST  
AREA ON SATURDAY. THIS WILL BE LITTLE MORE THAN A SMALL WIND SHIFT  
FROM THE WEST TO NORTH AS IT PASSES. AS FOR HIGHS SATURDAY: THERE  
WAS SOME DECENT SPREAD IN THE NUMERICAL GUIDANCE WITH THIS MORNING'S  
MODEL RUNS. THE MAV SOLN IS WARMEST WITH THE MET BEING THE COOLEST.  
THE INHERITED FORECAST WAS WEIGHTED MORE TOWARD THE COOLER MET  
GUIDANCE FOR HIGHS SATURDAY. DECIDED TO INCREASE HIGHS FOR SATURDAY  
UTILIZING A BLEND OF PERSISTENCE AND MAV GUIDANCE. BASED ON BUFKIT  
SOUNDINGS, THE NAM, SEEMS TO NOT MIX AS HIGH SATURDAY AFTERNOON,  
THUS THE COOLER TEMPS. BELIEVE THE GFS IS A BETTER SOLUTION HERE  
GIVEN THE EXPECTED FULL SUN AND DRY SOUNDING FORECAST WHICH  
FACILITATES BETTER MIXING SATURDAY AFTERNOON. ONE LAST POSSIBLE  
IMPACT TO TEMPERATURES IS SNOW COVER ACROSS THE SANDHILLS. FOR NOW,  
WILL FORECAST HIGHS ON THE NOTION THAT THIS SNOWCOVER WILL BE GONE  
SATURDAY. THIS NOTION SEEMS VERY PLAUSIBLE GIVEN THE FULL SUN TODAY,  
VERY DRY LOW LEVELS AS EVIDENCED BY THE 0.05 PWAT IN THE 12Z KLBF  
RAOB THIS MORNING, AND THE VERY DRY NATURE OF THE SNOW. UPPER LEVEL  
LOW PRESSURE WILL TRACK INTO THE FOUR CORNERS SATURDAY NIGHT.  
DOWNSTREAM OF THIS FEATURE, MID TO HIGH CLOUDINESS WILL SPREAD  
NORTHEAST INTO THE FORECAST AREA OVERNIGHT SATURDAY NIGHT. WITH THE  
APPROACHING SYSTEM AND DEEPENING LOW PRESSURE OVER FAR NORTHEASTERN  
NEW MEXICO, WINDS WILL INCREASE OVERNIGHT. THE INCREASING WINDS,  
COUPLED WITH INCREASED CLOUDINESS, SHOULD LEAD TO MILD LOWS FOR  
SATURDAY NIGHT. THE GUIDANCE HAD LOWS IN THE TEENS AND LOWER 20S.  
DECIDED TO TREND THESE HIGHER INTO THE 20S.  
   
LONG TERM
 
(SUNDAY THROUGH FRIDAY)  
ISSUED AT 328 PM CST FRI FEB 21 2020  
 
THE EXTENDED FORECAST IS HIGHLIGHTED BY TWO  
WEATHER SYSTEMS, FOLLOWED BY SEASONAL TEMPERATURES LATE NEXT WEEK.  
FOR SUNDAY AND SUNDAY NIGHT: THE UPPER LEVEL LOW OVER THE FOUR  
CORNERS SUNDAY MORNING WILL TRACK EAST ALONG THE NEW MEXICO/COLORADO  
BORDER, EMERGING IN THE VICINITY OF THE OKLAHOMA PANHANDLE BY 00Z  
MONDAY. THE MODELS ARE IN DECENT AGREEMENT WITH THE TRACK OF THE H5  
LOW WITH THIS SYSTEM AS THE PREFERRED TRACK IS ACROSS SOUTHWEST  
KANSAS/NORTHWEST OKLAHOMA SUNDAY EVENING INTO EAST CENTRAL KANSAS  
AND NW MISSOURI BY 12Z MONDAY. THE 12Z NAM SOLN HAS NOW COME INTO  
AGREEMENT WITH THE GFS, ECMWF AND CANADIAN SOLUTIONS WITH A MORE  
SOUTHERN TRACK TO THIS SYSTEM. YESTERDAY, THE 12Z NAM TRACKED THE  
LOW ACROSS NORTHERN KANSAS. THIS WOULD HAVE FAVORED DECENT POPS IN  
THE SOUTHERN HALF OF THE FORECAST AREA. WITH THE MORE SOUTHERN TREND  
OF THE MODELS, POPS WERE LOWERED ACROSS THE BOARD. UTILIZING THE  
NBM, POPS WERE LOWERED 20 TO 30 PERCENT ACROSS THE BOARD FROM THE  
PVS FORECAST. EVEN THAT MAY NOT BE ENOUGH AS IT IS LOOKING PRETTY  
DRY FOR ALL OF THE FORECAST AREA WITH THE EXCEPTION OF CHASE, HAYES  
AND FRONTIER COUNTIES. IN THESE AREAS QPF'S WILL BE LOW AND THE 30  
TO 40 POPS IN THESE AREAS ARE VERY "OPTIMISTIC" AT THIS JUNCTURE. A  
SECOND WEATHER SYSTEM WILL TAKE AIM AT THE FORECAST AREA MONDAY INTO  
TUESDAY EVENING. THIS WILL BE IN THE FORM OF A NORTHWESTERLY  
SHORTWAVE TROUGH, WHICH DEPENDING ON MODEL CHOICE, ACTUALLY CLOSES  
OFF OVER THE CENTRAL PLAINS MONDAY NIGHT INTO TUESDAY. PRECIPITATION  
IN ASSOCIATION WITH THIS FEATURE WILL START OFF AS RAIN ON MONDAY,  
FOLLOWED BY A QUICK CHANGEOVER TO SNOW AS COLDER AIR IS DRAWN INTO  
THE SYSTEM FROM THE NORTH. UNLIKE THE FIRST SYSTEM SUNDAY, THIS  
SYSTEM WILL HAVE PLENTY OF ARCTIC AIR TO WORK WITH, SO SNOW WILL BE  
THE PREDOMINANT PTYPE WITH THIS SYSTEM. ATTM, SNOWFALL WITH THIS  
SYSTEM APPEARS MOST PROBABLE ACROSS THE PINE RIDGE INTO NORTH  
CENTRAL NEBRASKA. WILL CONTINUE TO MESSAGE THE SNOW/COLD THREAT IN  
THE HWO. BEYOND TUESDAY NIGHT, DRY CONDITIONS ARE FORECAST.  
WEDNESDAY WILL BE COOL WITH A GRADUAL WARMUP INTO THE END OF THE  
WEEK. BY FRIDAY, HIGHS WILL REACH BACK INTO 40S.  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)  
ISSUED AT 530 PM CST FRI FEB 21 2020  
 
VFR AND CLEAR SKIES SHOULD PREVAIL THE NEXT 24 HRS ACROSS WESTERN  
AND NORTH CENTRAL NEBRASKA. WINDS WILL BE LIGHT TONIGHT, THEN  
INCREASE TO AROUND 10 KT FROM THE NORTHWEST DURING THE DAY  
SATURDAY.  
 

 
   
FIRE WEATHER
 
 
ISSUED AT 328 PM CST FRI FEB 21 2020  
 
FIRE WEATHER FORECAST CONCERNS WILL BECOME ELEVATED  
ON SATURDAY ACROSS FAR SOUTHWESTERN NEBRASKA OVER ZONE 210. DRY  
CONDITIONS CONTINUE IN THIS ZONE WHICH MISSED OUT ON THE SNOWFALL  
EARLIER IN THE WEEK. HIGHS WILL REACH THE LOWER 60S IN THIS AREA  
SATURDAY AFTERNOON WITH MINIMUM RH REACHING AROUND 20 PERCENT.  
LOOKING AT NUMERICAL GUIDANCE, FORECAST WIND SPEEDS FOR IMPERIAL ARE  
WELL BELOW CRITICAL CRITERIA FOR A RED FLAG WARNING. HOWEVER, GFS  
BUFKIT SOUNDINGS FOR IMPERIAL INDICATE A SMALL WINDOW WHERE WIND  
GUSTS COULD REACH AROUND 20 MPH SATURDAY AFTERNOON UNDER FULL  
MIXING. CONDITIONS WILL BE CLOSE TO RED FLAG CRITERIA TOMORROW  
AFTERNOON BUT NOT QUITE THERE JUST YET. AFTER CONVERSING WITH LOCAL  
FIRE OFFICIALS IN ZONE 210, THEY INDICATED FUELS WERE READY TO BURN.  
DECIDED TO CONTACT FIRE PARTNERS IN FAR SW NEBRASKA AND GIVE THEM A  
HEADS UP ON THE ELEVATED FIRE WEATHER CONDITIONS SATURDAY AFTERNOON.  
 

 
   
LBF WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SYNOPSIS...BUTTLER  
SHORT TERM...BUTTLER  
LONG TERM...BUTTLER  
AVIATION...TAYLOR  
FIRE WEATHER...BUTTLER  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab NE Page Main Text Page