144 
FXUS63 KGLD 160400
AFDGLD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
1000 PM MDT FRI MAR 15 2013

.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY) 
ISSUED AT 225 PM MDT FRI MAR 15 2013

A SURFACE TROUGH OF LOW PRESSURE WILL CONTINUE TO MOVE EAST THROUGH 
THE AREA THIS AFTERNOON.  BEHIND THE TROUGH WINDS MAY GUST UP TO 30 
MPH WITH RELATIVE HUMIDITIES RANGING FROM 10 TO 15 PERCENT.  AM 
EXPECTING THE WINDS TO DIMINISH AS TEMPERATURES COOL THIS EVENING.  

DURING THE EVENING A BACKDOOR COLD FRONT WILL MOVE INTO THE 
AREA...EXITING THE AREA DURING THE OVERNIGHT HOURS.  BEHIND THE 
FRONT WINDS WILL REMAIN LIGHT DUE TO THE INVERSION PREVENTING THE 
GUSTY 850MB WINDS BEHIND THE FRONT FROM REACHING THE GROUND.  IN 
ADDITION THE ENVIRONMENT WILL BEGIN TO SATURATE DOWN TOWARD THE 
SURFACE BEHIND THE FRONT CAUSING CLOUD COVER TO INCREASE.

SATURDAY A COUPLE 500MB SHORT WAVE TROUGHS WILL MOVE ACROSS THE AREA 
FROM THE WEST...WITH THE STRONGEST ONE MOVING THROUGH DURING THE 
AFTERNOON.  CROSS SECTIONS INDICATE THE BEST LIFT WILL BE TIED TO 
THE SHORT WAVE TROUGH AND THE RIGHT ENTRANCE OF A 500MB JET OVER 
NEBRASKA...WITH THE BEST INSTABILITY BEING CO-LOCATED WITH THE BEST 
LIFT.  AT THE SURFACE A SURFACE LOW WILL DEVELOP OVER SOUTHEAST 
COLORADO CAUSING THE COLD FRONT FROM THE PREVIOUS NIGHT TO MOVE BACK 
NORTH AS A WARM FRONT.  THERE IS STILL COME UNCERTAINTY AS TO 
EXACTLY HOW FAR NORTH THE FRONT WILL MOVE BEFORE STALLING DURING THE 
AFTERNOON...BUT THE CONSENSUS IS NEAR THE KS/NE BORDER.  AS A RESULT 
OF THE STALLED FRONT AND INCREASED LIFT DURING DURING THE 
AFTERNOON...HAVE INCREASED PRECIP. CHANCES FOR THE NORTH HALF OF THE 
AREA.  WITH THE MEAN STORM MOTION BEING PARALLEL TO THE 
FRONT...LOCATIONS ALONG THE FRONT MAY SEE A PROLONGED PERIOD OF 
RAINFALL DURING THE AFTERNOON.  THERE WILL BE SOME WEAK ISENTROPIC 
LIFT OVER THE WEST HALF OF THE AREA DURING THE LATE MORNING AND 
AFTERNOON ACCOMPANYING THE SHORT WAVE TROUGH...SO KEPT PRECIP. 
CHANCES IN THE FORECAST FOR THOSE LOCATIONS.  

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 220 PM MDT FRI MAR 15 2013

SATURDAY NIGHT...500 MB SHORT WAVE TROUGH WILL MOVE ACROSS THE AREA. 
GEOSTROPHIC FORCING PER LAYER Q VECTOR CONVERGENCE IS NOT GREAT...
BUT ADEQUATE ENOUGH FOR UPWARD VERTICAL MOTION. FRONTOGENETIC 
FORCING IS ALSO LACKING IN THE LOW LEVELS...THOUGH IS A LITTLE 
BETTER ABOVE 700 MB. THE CURRENT SET OF POPS SEEM A LITTLE 
HIGH...BUT WILL ONLY TWEAK THEM DOWN A LITTLE FOR THE SAKE OF 
CONSISTENCY. 

THE PHASE OF PRECIPITATION IS PROBLEMATIC FROM 06Z-12Z. MODEL 
SOUNDINGS SHOW A MIXED BAG OF DRIZZLE...LIGHT SNOW...AND LIGHT RAIN. 
CANNOT RULE OUT A FEW HOURS OF FREEZING DRIZZLE ESPECIALLY IN THE
EASTERN HALF OF THE FORECAST AREA...BUT CONFIDENCE IS NOT HIGH
ENOUGH TO MENTION YET. FOR THE SAKE OF SIMPLICITY...WILL JUST FORECAST
PRECIPITATION TYPE AS A MIXTURE OF LIGHT SNOW/LIGHT RAIN. THERE IS
A POTENTIAL TO GET AN INCH OF SNOW WITH THE SYSTEM BY SUNDAY
MORNING. 

SUNDAY...THE FIRST SHORTWAVE WILL MOVE EAST OF THE FORECAST 
AREA...BUT ANOTHER WAVE WILL MOVE ACROSS EASTERN COLORADO BY THE 
AFTERNOON. LOW LEVEL MOISTURE WILL BE LIMITED...BUT GFS DEPICTS AN 
AN AREA OF MIXED LAYER CAPES AROUND 400 J/KG BY THE AFTERNOON. 
THOUGH THE NAM IS NOT AS AGGRESSIVE WITH THE INSTABILITY...WILL 
INTRODUCE A SLIGHT CHANCE OF THUNDERSTORMS OVER THE COLORADO 
COUNTIES. ABUNDANT CLOUD COVER WILL KEEP TEMPERATURES IN THE UPPER 
40S AND 50S. 

MONDAY...A COLD FRONT WILL SWEEP ACROSS THE AREA EARLY IN THE 
MORNING. WINDS BEHIND THE FRONT WILL BE STRONG...LIKELY 20 TO 30
KNOTS WITH GUSTS TO 40 KNOTS. EXPECT TEMPERATURES TO DROP 5-10
DEGREES FROM SUNDAY.

TUESDAY THROUGH WEDNESDAY...MID LEVEL RIDGE WILL KEEP PROVIDE 
SLIGHTLY WARMER TEMPERATURES AND DRY WEATHER TO THE REGION. 

WEDNESDAY NIGHT THROUGH FRIDAY...LONG RANGE MODELS DEVELOP A DEEP
TROUGH OVER THE WESTERN UNITED STATES. A SERIES OF SHORT WAVES
WILL BRING ENOUGH UPWARD VERTICAL MOTION ACROSS THE HIGH PLAINS TO
MENTION PRECIPITATION THROUGH THE PERIOD. LOW LEVEL MOISTURE WILL
BE SOMEWHAT LIMITED...BUT THERE IS ENOUGH MODEL CONSISTENCY TO
MENTION A CHANCE OF LIGHT RAIN OR SNOW.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MDT FRI MAR 15 2013

VFR CONDITIONS EXPECTED AT KGLD AND KMCK. LATEST 00Z MODELS A BIT
MORE OPTIMISTIC IN KEEPING CIGS VFR AS A WEATHER DISTURBANCE MOVES
THROUGH DURING THE 15Z-06Z TIMEFRAME. HAVE RAISED CIGS TO VFR AS A
RESULT. STILL COULD SEE SOME LIGHT RAIN OR RAIN SHOWERS IN THE
19Z-01Z TIMEFRAME BUT CONFIDENCE NOT AS HIGH SO HAVE A TEMPO
GROUP. WINDS START THE PERIOD FROM THE NORTHEAST AROUND 10KTS THEN
VEER TO THE EAST BY 15Z THEN SOUTHEAST LATE IN THE PERIOD WITH
SPEEDS HOVERING IN THE 11-13KT RANGE WITH AN OCCASIONAL GUST.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...JTL
LONG TERM...MENTZER
AVIATION...99