FXUS63 KTOP 121230 AAA
AFDTOP

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TOPEKA KS
630 AM CST FRI MAR 12 2010

.UPDATE...

UPDATED FOR THE 12 UTC TAF ISSUANCE.

&&

.DISCUSSION...

SEE PREVIOUS DISCUSSION.

&&

.AVIATION...

AS UPPER LOW PIVOTS SOUTHEASTWARD ALONG THE MO RIVER...MVFR STRATUS
AND A RAIN/SNOW MIXTURE TO THE NORTH WILL DROP SOUTHEAST ACROSS
THE TAF SITES...ALTHOUGH PRECIP SHOULD FALL PRIMARILY AS RAIN.
THIS WILL MAINLY OCCUR IN THE 14Z-18Z TIMEFRAME...THEN DECREASING
VORTICITY ADVECTION WITH THE PASSAGE OF THE VORT LOBE WARRANTS VCSH
FOR THE REMAINDER OF THE DAY...AND DRY AFT 00Z. SHOULD ALSO SEE
WINDS THIS MORNING BECOME MORE NORTHWEST AND INCREASE WITH GUSTS
AOA 20 KTS. WILL KEEP MVFR CIGS THROUGH THE 00Z-12Z TIMEFRAME
AROUND 1500 FT WITH VFR VSBYS.

&&

.PREV DISCUSSION... /ISSUED 443 AM CST FRI MAR 12 2010/

DISCUSSION...

AN UPPER LOW OVER NORTHEAST NE EARLY THIS MORNING WILL MOVE
SOUTHWARD ACROSS THE KS AND MO BORDER TODAY...THEN SLOWLY SHIFT
SOUTHEAST ACROSS NORTHERN AR FRIDAY NIGHT. THE UPPER LOW MAY AMPLIFY
A BIT ON SATURDAY AS IT LIFTS NORTHEASTWARD INTO THE OH RIVER
VALLEY. WE MAY SEE THE WRAP AROUND MOISTURE CONTINUE TO PROVIDE FOR
A CHANCE OF SHOWERS ACROSS THE CWA FRIDAY NIGHT INTO SATURDAY BEFORE
ENDING SATURDAY NIGHT.

TODAY...AS THE UPPER LOW MOVES SOUTHWARD ACROSS THE CWA THE ASCENT
SHOULD INCREASE THROUGH THE DAY FOR AREAS OF LIGHT RAIN TO DEVELOP.
THE RAIN MAY MIX WITH SNOW ACROSS THE NORTHERN AND WESTERN COUNTIES
OF THE CWA. POINT FORECAST SOUNDINGS SHOW THE LOW-LEVELS WARMING
ENOUGH BY 18Z FOR ANY OF THE RAIN AND SNOW MIX TO CHANGE BACK TO
RAIN. HIGHS WILL CONTINUE TO BE COOL WITH TEMPERATURES ONLY REACHING
THE UPPER 30S ALONG THE NE BORDER TO THE MID 40S ACROSS THE EXTREME
SOUTHERN CWA. THE NORTHWEST WIND OF 15 TO 25 MPH WILL MAKE IT EVEN
FEEL COOLER.

TONIGHT...TEMPERATURES WILL DROP INTO THE MID TO UPPER 30S AFTER
SUNSET ALLOWING THE RAIN TO MIX WITH OR PERHAPS CHANGE OVER TO LIGHT
SNOW. THE BEST CHANCE FOR LIGHT SNOW WILL BE ACROSS NORTHEAST
COUNTIES WHERE VERTICAL THERMAL PROFILES WOULD SUPPORT LIGHT SNOW.
ANY ACCUMULATIONS ACROSS THE NORTHEAST COUNTIES WILL BE LESS THAN 1
INCH AND ROAD SURFACES SHOULD STAY ABOVE FREEZING THROUGH THE NIGHT.

HOPEFULLY...THE SHOWERS WILL BEGIN TO END FROM WEST TO EAST SATURDAY
AFTERNOON AS THE UPPER LOW ACROSS THE LOWER AND MID MS RIVER VALLEY
LIFTS NORTHEAST INTO THE OH RIVER VALLEY.

THE CLOUDS WILL PROBABLY CONTINUE THROUGH MID WEEK AS A COOL
AND MOIST NORTHWESTERLY FLOW BOTH ALOFT AND AT THE SFC CONTINUES
INTO THE MIDDLE OF NEXT WEEK. THE NEXT SOUTHERN STREAM UPPER TROUGH
SHOULD STAY WELL SOUTH OF THE CWA. THOUGH...BOTH THE EC AND GFS
CONTINUE TO SHOW A LONGER WAVE LENGTH TROUGH NEARLY STATIONARY EAST
OF THE CWA ACROSS THE MID AND LOWER MS RIVER VALLEY. THIS WILL ALLOW
MINOR UPPER LEVEL TROUGHS TO DIG SOUTHEAST ACROSS THE PLAINS AND
KEEP THE CLOUD COVER IN PLACE WITH SLIGHT CHANCES FOR RAIN THROUGH
MOST OF NEXT WEEK.

HIGHS SATURDAY AND SUNDAY WILL GRADUALLY WARM INTO THE MID TO UPPER
40S...PERHAPS LOWER 50S BY SUNDAY ACROSS THE SOUTHERN COUNTIES. IF
WE SEE SOME SUN NEXT WEEK...WE COULD WARM INTO THE MID TO UPPER 50S
BY THE MIDDLE AND END OF NEXT WEEK. HOWEVER...IF WE KEEP THE CLOUD
COVER THEN AFTERNOON HIGHS WILL ONLY REACH THE UPPER 40S TO LOWER
50S THROUGH NEXT THURSDAY. OVERNIGHT LOWS WILL BE IN THE 30S.

GARGAN

&&

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

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