National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KLBF 122313 AAA
AFDLBF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NORTH PLATTE NE
613 PM CDT SUN MAY 12 2013

.SYNOPSIS...
ISSUED AT 328 PM CDT SUN MAY 12 2013

UPPER LEVEL LOW PRESSURE...HAS MOVED EAST FROM WESTERN
ONTARIO INTO EASTERN ONTARIO OVER THE PAST 24 HOURS. A TROUGH
ASSOCIATED WITH THIS FEATURE...STRETCHED SOUTH INTO THE CAROLINAS.
FURTHER WEST...RIDING HAS AMPLIFIED ACROSS THE WESTERN THIRD OF THE
CONUS AND EXTENDED INTO THE CANADIAN PRAIRIE PROVINCES. AS OF THE 12Z
ANALYSIS...THE HIGH WAS CENTERED OVER NEVADA. A DECENT UPPER LEVEL
LOW WAS PRESENT OVER THE GULF OF ALASKA...WHICH HAS HELPED TO
ENHANCE THE WEST COAST RIDGING AS WELL.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM CDT SUN MAY 12 2013

MAIN CONCERNS WITH THE FORECAST FOR THIS PERIOD DEAL WITH
TEMPERATURES/WINDS/RELATIVE HUMIDITY FOR MONDAY.

A WARM FRONT MOVES THROUGH TONIGHT AND MONDAY MORNING TO BRING MUCH
WARMER AIR TO THE REGION AS THE UPPER LEVEL RIDGE BUILDS IN OVER THE
ROCKIES TONIGHT AND INTO THE PLAINS ON MONDAY. DURING THE DAY A
SURFACE TROUGH/DRY LINE SETS UP OVER NEBRASKA...ALMOST BISECTING THE
FORECAST AREA WEST TO EAST. EXPECTING DEEP MIXING IN THE
AFTERNOON...UP TO 650-700MB. MODELS ARE GIVING SURFACE DEWPOINTS
FROM THE MID 40S TO THE MID 50S ACROSS THE FORECAST AREA IN THE
AFTERNOON...BUT WITH THE MIXING EXPECTED...USED MIXED LAYER
DEWPOINTS FOR THE FORECAST MONDAY AFTERNOON...THIS GIVES VALUES IN
THE 30S AND 40S...WHICH SEEMS MUCH MORE REASONABLE FOR THE SCENARIO
IN PLACE. COULD BE SOME AFTERNOON CUMULUS DEVELOP...BUT WITH THE
AMOUNT OF DRY AIR WITH THIS AIRMASS...THINKING SKIES WILL STAY
MOSTLY SUNNY THROUGH THE DAY. WINDS ARE LOOKING TO STAY FAIRLY LIGHT
THROUGH THE DAY...AS SPEEDS ALOFT AREN/T VERY STRONG. AT PEAK
HEATING...WINDS AT THE TOP OF THE MIXED LAYER ARE 15-20KTS...SO NOT
ANTICIPATING MUCH...IF ANY BREEZY CONDITIONS. ALTHOUGH DO EXPECT A
WESTERLY COMPONENT FOR MOST AREAS IN THE AFTERNOON...WITH THE WINDS
BEING FAIRLY LIGHT...DON/T THINK THE DOWNSLOPE COMPONENT WILL HELP
ENHANCE WARMING MUCH. HOWEVER...THE SUN AND MIXING OF THE BOUNDARY
LAYER WILL HELP WITH WARMING POTENTIAL AS TEMPERATURES AT 850MB RISE
TO 22-26C BY LATE AFTERNOON...AND TO 9-10C AT 700MB. THIS TRANSLATES
TO UPPER 80S TO LOW 90S FOR THE ENTIRE AREA.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 PM CDT SUN MAY 12 2013

MID TERM...MONDAY NIGHT THROUGH WEDNESDAY...MAIN FORECAST CHALLENGE
CONTINUES TO DEAL WITH TEMPERATURES TUESDAY...FRONTAL TIMING TUESDAY
AFTERNOON/EARLY TUES EVE...THEN PRECIPITATION CHANCES TUESDAY NIGHT.
DRY AIR...MOSTLY CLEAR SKIES AND LIGHT WINDS ARE EXPECTED MONDAY
NIGHT...WHICH WILL RESULT IN OVERNIGHT LOWS MAINLY IN THE LOWER 50S.
SOME UPPER 50S TO AROUND 60 ARE POSSIBLE IN THE NORTHEASTERN ZONES
THANKS TO INCREASED WINDS AND A HIGHER DEGREE OF BL MOISTURE.
SHIFTING TO TUESDAY...FRONTAL TIMING AND TEMPERATURES CONTINUE TO BE
THE MAIN FORECAST ISSUES. LIKE YESTERDAY...THE NAM IS SLIGHTLY
FASTER WITH THE FROPA TUESDAY AFTERNOON. THIS IS IN CONTRAST TO THE
GFS/ECMWF SOLNS WHICH ARE ABOUT 3 HRS SLOWER. THIS MAY SEEM
MINOR...HOWEVER WITH THE FROPA EXPECTED IN THE LATE AFTERNOON/EARLY
EVENING HRS...ANY DEVIATION IN TIMING...COULD HAVE MAJOR IMPACTS ON
HIGH TEMPERATURES TUESDAY. FOR THIS FCST PACKAGE...LEFT HIGHS ALONE
IN THE SOUTH AND TRENDED THEM DOWN SLIGHTLY ACROSS THE NORTH...WHERE
AT LEAST THE ECMWF AND THE GFS PUSH THE FRONT THROUGH MY NRN TIER OF
COUNTIES BY 21Z TUESDAY. FURTHER SOUTH...AHEAD OF THE FRONT...ALL
THE INGREDIENTS ARE THERE FOR TEMPS IN THE LOWER TO MID
90S...INCLUDING DEEP MIXING TO AROUND 600MB...WESTERLY
WINDS...FAIRLY DRY AIR AND COMPRESSIONAL WARMING AHEAD OF THE FRONT.
FOR KLBF...WILL CONTINUE WITH 96 FOR THE FCST HIGH...WHICH WOULD BE
A NEW RECORD. THE BEFORE MENTIONED FRONT WILL PASS THROUGH THE FCST
AREA BY TUESDAY EVENING. AS IT DOES...THERE IS A SMALL THREAT FOR
THUNDERSTORMS LATE TUESDAY AFTERNOON AND EARLY TUESDAY EVENING. WITH
HIGHS IN THE 90S EXPECTED...LITTLE OR NO CAPPING INVERSION WILL
EXIST. COVERAGE SHOULD BE HIGHLY ISOLATED AND ELEVATED WITH SURFACE
DEW POINTS IN THE HIGH 30S TO MID 40S...SO SOME GUSTY WINDS MAY BE A
THREAT. THE FRONT WILL PUSH SOUTH INTO THE SRN PLAINS OVERNIGHT
TUESDAY NIGHT INTO WEDNESDAY...RESULTING IN A TEMPORARY COOL DOWN
WEDNESDAY WITH HIGHS IN THE UPPER 70S TO NEAR 80.

WEDNESDAY NIGHT THROUGH SUNDAY...DECENT LOW LEVEL MOISTURE RETURN
DEVELOPS ON THURSDAY AND PERSISTS THROUGH SUNDAY. THE PATTERN
ALOFT...WILL TRANSITION FROM ZONAL TO SWRLY TOWARD NEXT
WEEKEND...WHICH WILL ALLOW SEVERAL EMBEDDED DISTURBANCES TO TRACK
THROUGH THE CENTRAL AND NORTHERN PLAINS...INCREASING THE CHANCE FOR
PRECIPITATION FRIDAY THROUGH SUNDAY. BASED ON WHERE THE BEST
MOISTURE RETURN IS...WILL FAVOR THE HIGHEST POPS IN THE EAST WITH
ONLY SLIGHT CHANCES IN THE WEST. TEMPERATURES WILL WARM INTO THE
LOWER TO MID 80S FOR THURSDAY...FRIDAY AND SATURDAY. TEMPS WILL COOL
BACK INTO THE 70S FOR SUNDAY AS A DECENT COLD FRONT PASSES THROUGH
THE FCST AREA SAT NIGHT OR EARLY SUNDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 610 PM CDT SUN MAY 12 2013

VFR IS EXPECTED ALL AREAS TONIGHT AND MONDAY. LOW PRESSURE ACROSS
NRN CANADA WILL TRACK EAST TOWARD HUDSON BAY. SCATTERED TO BROKEN HIGH
CLOUDINESS WILL CONTINUE TO FILTER ACROSS THE FCST AREA DURING
THIS TIME.

&&

.FIRE WEATHER...
ISSUED AT 328 PM CDT SUN MAY 12 2013

TEMPERATURES WILL RISE INTO THE UPPER 80S TO MID 90S BOTH MONDAY AND
TUESDAY ACROSS THE DISTRICTS. THESE WARM TEMPERATURES...COMBINED
WITH LOW DEWPOINTS WILL DROP RELATIVE HUMIDITY DOWN AROUND 15 TO 20
PERCENT BOTH DAYS...TO BRING ABOUT ENHANCED CONCERN FOR FIRE DANGER.

MONDAY WILL BE LESS OF A CONCERN HOWEVER...AS WINDS ARE EXPECTED TO
STAY BELOW 25 MPH.

FOR TUESDAY...A COLD FRONT WILL MOVE SOUTH ACROSS THE DISTRICTS.
AHEAD OF...AND EVEN A BIT BEHIND THE FRONT...IT STILL IS LOOKING
GOOD FOR TEMPERATURES IN THE 90S TUESDAY AFTERNOON. NOT AS CONFIDENT
IN DEWPOINTS THOUGH AS MODELS HAVE NOT BEEN PERFORMING WELL WITH
MANY BEING TOO HIGH. HOWEVER...WITH THE VERY WARM
TEMPERATURES...EVEN DEWPOINTS IN THE 30S AND 40S WILL DROP RELATIVE
HUMIDITY TO AROUND 15 PERCENT. WINDS ARE MORE OF A QUESTION AS
MODELS ARE SHOWING LIGHT WINDS AHEAD OF AND ALONG THE FRONT. BELIEVE
THERE MAY BE A CHANCE FOR SOME ENHANCED MIXING JUST AHEAD OF THE
FRONT AS IT MOVES THROUGH...WHICH COULD BRING SOME STRONGER WINDS
FOR A SHORT TIME. THEN BEHIND THE FRONT...WINDS WILL SHIFT TO THE
NORTH/NORTHWEST AND INCREASE. IN ADDITION...LATER IN THE
AFTERNOON...IT DOES APPEAR THE CAP WILL BREAK...GIVING A CHANCE FOR
SOME THUNDERSTORMS. THESE STORMS COULD PRODUCE SOME STRONG WINDS.

THERE IS SOME TIMING DIFFERENCES IN THE SPEED OF THE COLD FRONT
COMING THROUGH ON TUESDAY AFTERNOON...WHICH WILL IMPACT WHAT AREAS
WILL SEE THE HIGHEST CONCERN FOR RED FLAG CONDITIONS. DUE TO THIS
UNCERTAINTY...ALONG WITH UNCERTAINTY IN THE WINDS...WILL FORGO ANY
FIRE WEATHER HEADLINES AT THIS POINT.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CLB
SHORT TERM...BROOKS
LONG TERM...CLB
AVIATION...CDC
FIRE WEATHER...BROOKS