FXUS63 KSGF 121135
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
635 AM CDT MON MAY 12 2008

...UPDATE TO AVIATION...

.DISCUSSION...

CURRENTLY...STRONG UPPER LEVEL STORM SYSTEM IS PUSHING EAST THROUGH
THE EAST COAST STATES...WITH UPPER LEVEL RIDGING BUILDING INTO THE
CENTRAL PLAINS. RIDGE OF SURFACE HIGH PRESSURE IS CENTERED OVER
THE AREA...WITH CALM WINDS TEMPERATURES HAVE DROPPED INTO THE
40S AND UPPER 30S EARLY THIS MORNING.

AFTER A COOL START TO THE DAY TEMPERATURES SHOULD REBOUND
QUICKLY...AS AN UPPER LEVEL RIDGE AND WARM AIR ADVECTION MOVES
INTO THE AREA. 850MB TEMPERATURES WILL WARM INTO THE LOWER
TEENS...WHICH ACCORDING TO CONDITIONAL CLIMATOLOGY RESULTS IN
HIGHS IN THE MIDDLE TO UPPER 70S.

A TROUGH DEEPENS ACROSS THE NORTHERN PLAINS ON TUESDAY...WITH A
LOW LEVEL JET INCREASING OUT OF THE SOUTH ACROSS THE REGION.
THIS LOW LEVEL JET SHOULD HELP PULL GULF MOISTURE BACK INTO THE
REGION ON TUESDAY. THE COLD FRONT THAT PASSED THROUGH THE REGION
ON SATURDAY HAS NOW MOVED INTO THE GULF WITH DEWPOINTS IN THE
40S ALONG THE NORTHERN GULF. DO HAVE A LITTLE CONCERN THAT THE
MODELS MAY BE SLIGHTLY OVER DOING THE MOISTURE RETURN AHEAD OF
THIS NEXT SYSTEM. HOWEVER...SHOULD STILL SEE DEWPOINTS RETURN TO
THE 60S ACROSS THE WESTERN CWA. THE MOISTURE WILL MOST LIKELY HAVE
TO TRAVEL THROUGH TEXAS TO REACH THE AREA. THIS WOULD LEAVE THE
GREATEST MOISTURE RETURN ACROSS THE WESTERN CWA.

INITIALLY THE AREA SHOULD BE WELL CAPPED TUESDAY MORNING AND DURING
THE EARLY AFTERNOON HOURS...AS 700MB TEMPERATURES ARE IN THE 7 TO 9C
RANGE ACROSS THE AREA. DURING THE AFTERNOON THE UPPER LEVEL TROUGH
WILL APPROACH THE REGION...WHICH WILL COOL TEMPERATURES ALOFT
WEAKENING THE CAP. THE TROUGH AND A SURFACE COLD FRONT WILL PUSH
INTO EASTERN KANSAS DURING THE LATE AFTERNOON HOURS ON TUESDAY.
TEMPERATURES SHOULD WARM WELL INTO THE 70S...AND DEWPOINTS SHOULD
INCREASE INTO THE 60S AHEAD OF THE FRONT. THIS WILL RESULT IN
MODERATE INSTABILITY DEVELOPING WITH CAPE VALUES IN THE 1000 TO
1500 J/KG RANGE. WITH THE CAP WEAKENING...WITH LIKELY SEE
CONVECTION FIRE IN EASTERN KANSAS AND WESTERN MISSOURI DURING THE
LATE AFTERNOON AND EVENING HOURS OUT AHEAD OF THE FRONT. STEEP
LAPSE RATES WILL BE IN PLACE MAKING LARGE HAIL POSSIBLE WITHIN THESE
STORMS. SHEAR WILL ALSO BE SIGNIFICANT WITH 0-6KM BULK SHEAR IN
THE 50 TO 60KT RANGE. IF STORMS ARE ABLE TO BECOME SURFACE BASED
ALL MODELS OF SEVERE WEATHER WILL BE POSSIBLE TUESDAY AFTERNOON
AND EVENING...GENERALLY WEST OF HIGHWAY 65. THERE WILL BE STRONG
WARM AIR ADVECTION ACROSS THE AREA TUESDAY MORNING...WITH THE CAP
IN PLACE SHOULD NOT SEE MUCH CONVECTION...BUT THERE COULD BE
ENOUGH CLOUD COVER DEVELOP TO KEEP AFTERNOON HIGHS SLIGHTLY COOLER. THIS
WOULD LIMIT THE SURFACE BASE CONVECTION IF ENOUGH CLOUDS CAN
DEVELOP WITHIN THIS WARM AIR ADVECTION.

THE COLD FRONT WILL PUSH THROUGH THE AREA TUESDAY EVENING THROUGH
THE OVERNIGHT HOURS. STORMS SHOULD DEVELOP ALONG THE FRONT AS IT
PUSHES THROUGH THE AREA. COULD SEE SMALL TO MARGINALLY SEVERE HAIL
AND DAMAGING WINDS WITH THIS ACTIVITY AS IT PUSHES THROUGH THE
AREA TUESDAY NIGHT.

THE FRONT SHOULD STALL ACROSS CENTRAL ARKANSAS ON TUESDAY... AND
MAY MEANDER TO THE NORTH AND SOUTH DURING THE WEDNESDAY
NIGHT THROUGH FRIDAY TIME PERIODS. AN UPPER LEVEL LOW WILL BE IN
PLACE ACROSS TEXAS WHICH WILL SEND ENERGY TO THE NORTHEAST ALONG THE
STALLED FRONT. MODELS SHOW MOST OF THIS ACTIVITY STAYING TO THE
SOUTH OF THE AREA...WITH JUST THE SOUTHERN CWA BEING AFFECTED.
THEREFORE...HAVE KEPT SLIGHT TO CHANCE POPS GOING ALONG THE
SOUTHERN CWA WEDNESDAY NIGHT THROUGH FRIDAY. THE WARM SECTOR SHOULD
REMAIN SOUTH OF THE AREA DURING THIS TIME...SO SEVERE WEATHER CHANCES
SHOULD REMAIN WELL TO THE SOUTH OF THE AREA. THURSDAY INTO FRIDAY
THE LOW SHOULD OPEN UP AND PUSH THROUGH THE AREA...LEAVING A DRY
WEEKEND ACROSS THE AREA.

WISE


&&

.AVIATION...

FOR THE 12Z TAFS...HIGH PRESSURE WILL SHIFT EAST OF THE AREA TODAY
WITH SURFACE WINDS RETURNING TO THE SOUTHEAST. COULD SEE SOME
GUSTS UP TO 25 KTS THIS AFTERNOON. PRESSURE GRADIENT WILL INCREASE
TONIGHT WITH LOW DEVELOPING OUT OVER THE PLAINS. SOME CIRRUS WILL
BUILD INTO THE AREA TONIGHT BUT CONDITIONS SHOULD REMAIN VFR.

LINDENBERG

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$