FXUS63 KEAX 271740
AFDEAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1139 AM CST FRI NOV 27 2009
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
MAIN CHANGE TO FORECAST IS TO SCALE BACK PRECIPITATION CHANCES
SUNDAY AND SUNDAY NIGHT TO JUST THE SLIGHT CHANCE CATEGORY.
CURRENTLY...SURFACE RIDGE AXIS HAS PASSED TO THE EAST OF THE
FORECAST AREA...ALLOWING A LIGHT SOUTHWEST TO SOUTH FLOW TO RETURN.
WILL SEE THIS FLOW INCREASE SOME TODAY...ALTHOUGH FORECAST SOUNDINGS
SHOW SHALLOW MIXING ONLY TO ABOUT 925 MB...WITH MUCH WARMER AIR
ABOVE THIS LAYER. IF WE SHOULD BE ABLE TO MIX DEEPER...THEN WE COULD
SEE SIGNIFICANTLY WARMER TEMPERATURES...BUT GIVEN THE LATE NOVEMBER
TIMEFRAME...WILL GO WITH THE FORECAST SOUNDING IDEA OF SHALLOW
MIXING. ALSO...WITH STARTING OFF IN THE UPPER 20S TO LOW 30S...A 30
DEGREE DIURNAL SEEMS REASONABLE. SO FOR TEMPERATURES WILL GO WITH
THE HIGH END OF THE GUIDANCE NUMBERS.
TONIGHT SHOULD BE RELATIVELY MILD WITH A SOUTHWEST FLOW CONTINUING
AHEAD OF AN APPROACHING COLD FRONT. ALTHOUGH WINDS MAY GO
LIGHT...NOT EXPECTING CALM CONDITIONS TO DEVELOP...EVEN IN THE MORE
SHELTERED SITES...SO NOT LOOKING FOR MUCH OF A RADIATIONAL EFFECT
DESPITE SKIES REMAINING MOSTLY CLEAR.
FOR THE DAY ON SATURDAY...TEMPERATURES BECOME A BIT MORE TRICKY...AS
SURFACE FRONT WILL START TO PUSH INTO THE FORECAST AREA BY AFTERNOON
AND MORE CIRRUS FROM A SOUTHERN STREAM SHORT WAVE MOVING INTO
OKLAHOMA...MAY ALSO IMPACT THE AREA. FORECAST SOUNDINGS SHOW MIXING
MAY BE SLIGHTLY DEEPER...AND GIVEN WE WILL START OFF A LITTLE
WARMER...WILL TREND TOWARD THE HIGH END OF THE GUIDANCE NUMBERS.
REGARDING PRECIPITATION CHANCES...WILL HAVE TO WATCH AS THE WEAK
SOUTHERN STREAM OKLAHOMA WAVE MOVES ACROSS SOUTHERN MISSOURI AND
ARKANSAS SATURDAY NIGHT...WITH THE SURFACE FRONT EXPECTED TO BE
ACROSS THE OZARKS BY 12Z SUNDAY. SOUNDINGS SHOWING MOISTURE FROM
THIS SYSTEM ABOVE 500 MB...BUT LITTLE INSTABILITY IN THIS LAYER AS
LIFT FROM THE SOUTHERN STREAM SYSTEM REMAINS FOCUSED ACROSS THE
OZARKS AND ARKANSAS. LOW LEVEL MOISTURE WILL BE QUITE LIMITED AT
THIS TIME AS LOW LEVEL RIDGING STRENGTHENS WITH A NORTHERLY FLOW
THROUGH AT LEAST 800 MB BY 12Z. SO WILL KEEP CONDITIONS DRY.
ON SUNDAY...POSITIVELY TILTED NORTHERN STREAM WAVE WILL BE MOVING
THROUGH THE UPPER MIDWEST...WITH SURFACE FRONT PUSHED WELL SOUTH OF
THE FORECAST AREA. BETTER MOISTURE WILL REMAIN CHANNELED IN THE
SOUTHERN STREAM FLOW ACROSS OKLAHOMA...ARKANSAS AND INTO THE
MISSOURI OZARKS...WITH FORECAST AREA ON THE NORTHERN FRINGES OF THE
MOISTURE BETWEEN 850 AND 900 MB. THUS THINK ONLY SLIGHT CHANCES FOR
THE SOUTHERN HALF OF THE FORECAST AREA AT BEST FOR POPS. THE
NORTHERN STREAM SYSTEM WILL BE BRINGING PLENTY OF MOISTURE ABOVE 600
MB...SO CIRRUS WILL DEFINITELY LIMIT SUNSHINE...THUS WITH NORTHERLY
LOW LEVEL FLOW AND CLOUDY SKIES...SHOULD SEE TEMPERATURES AT OR
SLIGHTLY BELOW NORMAL FOR DAYTIME HIGHS WITH LESS THAN A 10 DEGREE
DIURNAL.
FOR SUNDAY NIGHT...MID LEVEL WAVE SHOULD BE MOVING PAST BY THE
EVENING HOURS...AND AGAIN MOISTURE REMAINS LIMITED. WILL REMOVE POPS
FROM ALL BUT SOUTHERN THIRD OF FORECAST AREA...AND KEEP THOSE IN THE
SLIGHT CHANCE CATEGORY.
PC
&&
.AVIATION...
FOR THE 18Z TAFS...SOUTH-SOUTHWEST WINDS AT 5 TO 10 KNOTS WILL
PREVAIL WITH GENERALLY CLEAR SKIES THROUGH THE PERIOD.
EB
&&
.CLIMATE...
THE CURRENT FORECAST LOW TEMPERATURE AT KANSAS CITY THROUGH SUNDAY
MAKES IT UNLIKELY THAT A HARD FREEZE (TEMPERATURES AT OR BELOW 28
DEGREES) WILL OCCUR THROUGH AT LEAST NOVEMBER 29TH. THAT DATE STANDS
AS THE LATEST OCCURRENCE OF 28 DEGREES. HERE ARE THE TOP 5 LATEST
OCCURRENCES OF 28 DEGREE LOW TEMPERATURES IN KANSAS CITY:
RANK DATE YEAR
----- ------ ------
? ?????? 2009
1 NOV 29 1905
2 NOV 27 1944
3 NOV 26 1902
4 NOV 26 1958
5 NOV 25 1928
FOR ADDITIONAL INFORMATION...PLEASE VISIT OUR WEBSITE AT
WWW.WEATHER.GOV/KC.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
