FXUS63 KOAX 192001
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
301 PM CDT SAT MAR 19 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY.
MAIN CONCERN IN THE SHORT TERM WILL BE MOISTURE AVAILABILITY AND
LOCATION OF BOUNDARIES.
WIDESPREAD AREA OF CONVECTION WAS LOCATED ACROSS PARTS OF KANSAS
INTO WESTERN MISSOURI AT 18Z ASSOCIATED WITH SPEED MAX OVER
SOUTHEAST NEBRASKA IN ADVANCE OF WESTERN TROUGH. THIS FEATURE IS
EXPECTED TO PROPOGATE EAST THIS AFTERNOON WITH ANOTHER MAX MOVING
INTO THE NORTHERN PLAINS TONIGHT INTO SUNDAY. UPPER DIVERGENCE
ASSOCIATED WITH THE SECOND MAX SHOULD HELP DEVELOP CONVECTION NORTH
ACROSS THE AREA TONIGHT AS SURFACE TROUGH APPROACHES FROM THE WEST.
LOW LEVELS PRETTY DRY RIGHT NOW WITH DEW POINTS IN THE 20S ACROSS
EASTERN NEBRASKA AND SOUTHWEST IOWA BUT SHOULD INCREASE AS SURFACE
TROUGH MOVES SLOWLY EAST INTO WESTERN NEBRASKA BY SUNDAY MORNING.
FORECAST TRENDS GENERALLY THE SAME WITH POPS INCREASING TONIGHT
AND DECREASING ON SUNDAY AS SURFACE FRONT AND UPPER WAVE TRACK
EAST. 12Z MODELS SIMILAR IN STALLING THE FRONT NEAR THE SOUTHEAST
BORDER OF NEBRASKA SUNDAY NIGHT INTO MONDAY THEN LIFT SLOWLY NORTH
MONDAY NIGHT BEFORE NEXT FRONT COMES THROUGH ON TUESDAY FOR A
CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS OVER THE AREA AS
MAIN UPPER WAVE LIFTS TOWARD THE NORTHERN PLAINS. SPRINGLIKE
TEMPERATURES REMAIN IN THE FORECAST SO NO WORRY OF SNOW WITH THIS
SYSTEM...BUT TEMPERATURES WILL BE HIGHLY DEPENDENT ON LOCATION OF
THE SURFACE BOUNDARIES.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.
PERIOD BEGINS WITH STRONG UPPER LOW MOVING ACROSS THE NORTHERN
PLAINS AND SURFACE COLD FRONT PUSHING INTO THE FORECAST AREA. MOST
OF THE PRECIPITATION SHOULD BE ENDING LATE TUESDAY NIGHT AS THE
UPPER LOW CONTINUES TO QUICKLY MOVE EAST SOUTHEAST. THIS WILL ALLOW
COLDER AIR TO SPREAD OVER THE AREA WITH 850MB TEMPERATURES FALLING
INTO THE NEGATIVE SINGLE DIGITS IN OUR NORTHERN COUNTIES THRU
FRIDAY. A QUICK MOVING SHORTWAVE IS FORECAST TO MOVE ACROSS THE
CENTRAL PLAINS ON THURSDAY WHICH COULD BRING ANOTHER CHANCE OF
PRECIPITATION TO THE AREA. TEMPERATURES ARE FORECAST TO BE COLD
ENOUGH FOR SNOW IN THE NORTH WITH MAINLY RAIN IN OUR SOUTH. IF THIS
SYSTEM CONTINUES TO BE QUICK MOVING...WE SHOULD END UP WITH ONLY
LIGHT PRECIPITATION AMOUNTS. A STRONGER TROF MOVES INTO THE CENTRAL
PLAINS LATE IN THE PERIOD BUT MODEL AGREEMENT IS LOW. WL ADD A SMALL
POP IN FOR NEXT WEEKEND.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
MOISTURE WILL CONTINUE TO STREAM NORTHWARD ACROSS EASTERN NEBRASKA
THROUGH TONIGHT. THIS WILL IMPACT TAF SITES BY BOTH LOWERING
CEILINGS AND VISIBILITIES...ESPECIALLY AFTER DARK...MOST LIKELY INTO
IFR CATEGORY IF NOT LIFR. THUNDERSTORMS WILL MOVE ACROSS EASTERN KS
THROUGH THIS EVENING...POSSIBLY SPREADING INTO SERN NEBRASKA BUT
LIKELY STAYING SOUTH OF TAF SITES. THUNDERSTORMS COULD SPREAD
FARTHER NORTH LATER TONIGHT AS LOW LEVEL WINDS BECOME MORE
SOUTH/SOUTHWEST AND STRENGTHENS A BIT. ALTHOUGH TIMING AND COVERAGE
OF THUNDERSTORMS WERE NOT CERTAIN ENOUGH TO INCLUDE THUNDERSTORM
MENTION IN TAF FORECAST...DID MENTION CB WITH PROB30 GROUPS. THE
STRONG LOW LEVEL WINDS COULD ALSO PRODUCE LOW LEVEL WIND SHEAR AT
TAF SITES AS SURFACE WINDS DECOUPLE A BIT AND MENTION WAS MADE IN
FORECASTS. LOW CLOUDS/VISIBILITIES SHOULD LIFT ON SUNDAY...BUT
PROBABLY NOT UNTIL CLOSE TO OR AFTER 20/18Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
FOBERT/KERN/CHERMOK