Area Forecast Discussion
Issued by NWS North Platte, NE

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

830
FXUS63 KLBF 082023
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
223 PM CST MON FEB 8 2016

.SYNOPSIS...
ISSUED AT 221 PM CST MON FEB 8 2016

ANOMALOUS UPPER RIDGE REMAINS ANCHORED IN THE WEST WHILE LARGE UPPER
LOW SITUATED OVER THE GREAT LAKES REGION SINKS SLOWLY SOUTHWARD.
100M+ HEIGHT RISES OCCURRING ACROSS THE NRN HIGH PLAINS AT H5 IN
BETWEEN THESE TWO FEATURES AND THESE HEIGHT RISES ARE PROGGED TO
CONTINUE MOVING SEWD AS WELL. IR SAT PICS INDICATING MID LEVEL
CLOUDINESS IN THE TRANSITION ZONE AS WELL AS WEAK ISENTROPIC LIFT
AND ASSOCIATED MID LEVEL FRONTOGENESIS DEVELOPS IN CONCERT. FURTHER
WEST...STRONG ONSHORE FLOW OVER WRN BC AND WEAK UPPER LOW
UNDERCUTTING WRN STATES RIDGE AS A PV ANOMALY MOVES THROUGH NRN
MEXICO INTO WRN TX.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 221 PM CST MON FEB 8 2016

WINDS WILL EVENTUALLY DROP OFF WITH SUNSET AND SFC PRESSURE GRADIENT
IS WEAKENING ALREADY IN THE PANHANDLE. WEAK MID LEVEL FRONTOGENESIS
AND ASSOCIATED ISENTROPIC LIFT DEVELOPING MID LEVEL CLOUDINESS
ACROSS THE NRN PLAINS AND INTO THE NWRN PORTION OF THE FORECAST
AREA.

THE PREVIOUSLY MENTIONED MID LEVEL LIFT COMES AHEAD OF NEXT PV
ANOMALY ROUNDING THE WRN STATES UPPER RIDGE. THIS FEATURE AND THE
TEMPORARY FLATTENING OF THE WRN RIDGE WILL INCREASE THE ISENTROPIC
LIFT ACROSS THE NRN PLAINS LATE TONIGHT AND TMRW AND WILL BE ABLE TO
WORK WITH AVAILABLE MOISTURE STREAMING OVER THE RIDGE TO DEVELOP
LIGHT PRECIPITATION TMRW ACROSS THE N. SOME NEG EPV LOCATED IN THE
ZONE OF ISENTROPIC LIFT AND MODELS HINTING AT SHOWER-TYPE PRECIP IN
THE FORM OF SNOW ONCE SATURATION TAKES PLACES FROM TOP DOWN. WHILE
TEMPS DO EXCEED THE FREEZING MARK BY AFTERNOON AT THE SFC...SOUNDING
PROFILES IN THE NRN FCST AREA SUGGESTS GOOD ISOTHERMAL LAYER IN THE
ACCRETION ZONE AND WET BULB STILL BELOW ZERO C.

TEMPS WILL BE SIGHTLY WARMER TMRW BUT TEMPERED BY THE INCREASED
CLOUD COVER ASSOCIATED WITH THE WARM AIR ADVECTION AND ISENTROPIC
LIFT MENTIONED. WINDS HOWEVER WILL BE LIGHTER MAKING IT FEEL WARMER
OVERALL.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 221 PM CST MON FEB 8 2016

LOOKING AT A NORTHEAST-SOUTHWEST CROSS-SECTION ACROSS NEBRASKA
TUESDAY NIGHT...A LAYER OF WEAK FRONTOGENETIC FORCING CAN BE SEEN IN
THE 275-295K LAYER WHICH IS VERY STABLE. THE TEMPERATURE AT THE TOP
OF THAT LAYER IS EXPECTED TO BE -10C TO -14C WHICH COULD PRODUCE A
MIX OF CRYSTAL TYPES FALLING THROUGH AN ISOTHERMAL SATURATED LAYER
IN NORTHEAST NEBRASKA. THOUGH THE FORCING IS WEAK...IT COULD STILL
RESULT IN SOME LIGHT SNOW WITH LITTLE OR NO ACCUMULATION.

ON SUNDAY...A FRONT IS EXPECTED TO PRODUCE SOME SYSTEM-RELATIVE LIFT
INTO A MARGINALLY UNSTABLE LAYER OVER CENTRAL AND NORTHEAST
NEBRASKA. HOWEVER SOURCE LAYER IS RELATIVELY DRY WITH TEMPERATURES
ABOVE 0C. PRECIPITATION FALLING THROUGH THE LAYER COULD BE EXPECTED
TO COOL THE LAYER TO BELOW 0C...BUT THE LOWEST LAYER WOULD STILL BE
ABOVE FREEZING AND RAIN IS THE LIKELY FORM OF PRECIPITATION THAT
DOES FALL...AT LEAST IN THE AFTERNOON. THERE IS A SLIGHT POSSIBILITY
OF SNOW IN THE MORNING. WITH THE LOW RELATIVE HUMIDITY EXPECTED...WE
WILL KEEP THE PROBABILITY LOW AT LESS THAN 25 PERCENT.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1155 AM CST MON FEB 8 2016

WINDY CONDITIONS CONTINUE THROUGH AT LEAST MID AFTERNOON BUT WILL
BEGIN TO DECREASE AS PRESSURE GRADIENT BEGINS TO WEAKEN. MID LEVEL
FORCING FOR ASCENT IN THE FORM OF FRONTOGENESIS IS DEVELOPING MID
LEVEL CLOUDS ACROSS WRN SD AND INTO THE PANHANDLE OF NEB AND THIS
WILL PROGRESS EWD THIS AFTERNOON. AS HEIGHTS CONTINUE TO RISE AS
UPPER LONG WAVE TROUGH SLIDES SEWD ACROSS THE MIDWEST AND GREAT
LAKES AREA AND ANOMALOUS UPPER RIDGE BUILDS EWD...WEAK WARM AIR
ADVECTION AND ASSOCIATED ISENTROPIC LIFT WILL INCREASE OVERNIGHT
AND TWD THE END OF THE TAF PERIOD. AS A RESULT LIGHT SNOW MAY
DEVELOP MAINLY ACROSS THE N AND HAVE INCLUDED IN THE VTN TAF AS A
TEMPO GROUP AFTER 091200. HAVE LEFT OUT OF KLBF TAF FOR NOW.


&&

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

$$

SYNOPSIS...STOPPKOTTE
SHORT TERM...STOPPKOTTE
LONG TERM...SPRINGER
AVIATION...STOPPKOTTE



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.