Severe Thunderstorm Warning 141, NWS Springfield, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
235 PM CDT SUN JUN 25 2000

THE CHANCE OF RAIN AND RESULTING FLOOD THREAT WILL BE THE PRIMARY
FORECAST CONCERNS THIS FORECAST PERIOD.

LATEST SFC ANALYSIS SHOWS WEAK STATIONARY FRONT BISECTING THE
CWA...LIKELY THE REMAINS OF OVERNIGHT CONVECTION. SOME CONVERGENCE
ALONG THIS BOUNDARY...AND HEALTHY TCU FIELD SUGGESTS ISOLD
CONVECTION WILL CONTINUE DEVELOP INVOF THIS BOUNDARY DURING THE
AFTERNOON. MAIN THREAT WILL BE HEAVY RAIN...AS WEAK LAPSE RATES AND
SHEAR PROFILES SUPPORT ONLY BRIEF PULSE STORMS.

VERY DIFFICULT FORECAST AT HAND WITH MANY FACTORS EXPECTED TO PLAY A
ROLE IN TIMING...AMOUNT...AND DURATION OF HEAVY RAINFALL OVER THE
NEXT 24-36 HOURS. MODELS DIFFER SUBSTANTIALLY ON STRENGTH...
TIMING...AND LOCATION OF UPR LVL S/W EXPECTED TO ENHANCE CONVECTION
ALONG COLD FRONT CURRENTLY DROPPING OUT OF THE CENTRAL PLAINS. ANY
OUTFLOW BOUNDARIES LEFT OVER FROM ONGOING CONVECTION...AS WELL AS
ANTICIPATED CONVECTION IN KS...WILL ONLY ADD TO THE COMPLEXITY OF
THE SITUATION.

DUE TO THE NUMEROUS MESOSCALE INFLUENCES ON THE SYNOPTIC SCALE HEAVY
RAIN EVENT PROGGED TO OCCUR OVERNIGHT AND MONDAY...HAVE OPTED TO USE THE
MESO-ETA WITH A BLEND OF THE QPF FROM THE NGM. INTERESTINGLY
ENOUGH...NGM WAS THE ONLY MODEL THAT HAS HANDLED THE INTENSITY OF
ONGOING CONVECTION ACROSS OK AND NE...AND MAY NOT BE INCORRECT IN
BRINGING PRECIP BULLSEYE FURTHER EAST ACROSS CENTRAL MO TOMORROW.

WILL SEE T-STORM COMPLEX RAPIDLY DEVELOP ACROSS NE/KS...AND SLOWY
PROPAGATE SE. LOW LEVEL JET WILL CONTINUE INFLUX OF DEEP MOISTURE
FROM GULF INTO THIS COMPLEX OVERNIGHT. WOULD EXPECT MCS TO EVOLVE
FROM SQ LN INTO HEAVY RAIN PRODUCER TOWARD MORNING...AS INSTABILITY
WEAKENS...AFFECTING NRN ZONES BEFORE 12Z. WHILE MORNING ARRIVAL OF
SYSTEM IS TYPICALLY UNFAVORABLE FOR SUSTAINING AN MCS...STRONG
SYNOPTIC ASCENT AHEAD OF COLD FRONT AND UPR S/W WILL COMBINE WITH
STRONG 850MB BAROCLINIC GRADIENT AND VERY HIGH SFC-700MB THETA-E
VALUES TO MAINTAN CONVECTION.

MODEL FCST SOUNDINGS ACROSS WRN CWA INDICATE PW VALUES IN EXCESS
OVER 2"...AND GIVEN LOW FLASH FLOOD GUIDANCE...WILL ISSUE A FLASH
FLOOD WATCH ACROSS WRN HALF OF CWA FOR LATE TONIGHT AND MONDAY.

AS HINTED BY MODEL TRENDS...FRONT WILL CONTINUE TO SLOW AS IT MOVES
ACROSS THE CWA. STRENGTH OF SFC RIDGE BUILDING ACROSS THE CENTRAL
PLAINS...AS WELL AS INFLUENCE OF MESOSCALE BOUNDARIES...WILL
DETERMINE IF FRONT CLEARS CWA BEFORE RUNNING OUT OF STEAM. IF FRONT
SLOWS ENOUGH...THEN ANY INSOLATION ACROSS SE COUNTIES WOULD ONLY
ENHANCE CHANCE FOR REDEVELOPMENT AND HEAVY RAINFALL THERE AS WELL.

IN THE XTNDD...WILL SEE BELOW NORMAL TEMPERATURES AND A CONTINUED
CHANCE OF PRECIPITATION AS NW FLOW BECOMES ESTABLISHED OVER THE
CENTRAL US. POOR RESOLUTION OF EXTENDED MODELS NOT ABLE TO PICK OUT
EMBEDDED SHORT WAVES IN MEAN FLOW...AND THEREFORE WILL NOT GET PICKY
WITH WORDING. APPEARS THAT SEVERAL CHANCES FOR MCS DEVELOPMENT WILL
OCCUR ALONG STALLED OUT BOUNDARY BETWEEN TUESDAY AND THURSDAY.

THANKS FOR THE COORDINATION ICT...EAX...AND STL.

PRELIMINARY CCF NUMBERS...
SGF TE 070/078 062/078 061 145+64
JLN TE 072/078 062/079 061 145+64
UNO TE 070/085 064/079 062 143774
VIH TE 068/076 060/077 060 146+54

.SGF...FLASH FLOOD WATCH FOR LATE TONIGHT AND MONDAY ALONG AND WEST
OF A LINE FROM BRANSON...TO MARSHFIELD...TO LEBANON...TO VIENNA.

BOOKBINDER

KSZ073-097-101-MOZ055>058-066>071-077>083-088>098-101>106-260900-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPRINGFIELD MO
459 PM CDT SUN JUN 25 2000

...FLASH FLOOD WATCH LATE TONIGHT AND MONDAY FOR SOUTHEAST KANSAS
AND PORTIONS OF SOUTHWEST AND SOUTH CENTRAL MISSOURI...

A SLOW MOVING COLD FRONT WILL COMBINE WITH A VERY MOIST AND UNSTABLE
ATMOSPHERE TO PRODUCE ANOTHER THREAT OF HEAVY RAIN OVER PORTIONS OF
THE OZARKS. THE HEAVY RAIN SHOULD BEGIN DURING THE EARLY MORNING
HOURS ON MONDAY AND CONTINUE INTO MONDAY AFTERNOON.

THE WATCH AREA IS ALONG AND WEST OF A VIENNA TO KIMBERLING CITY LINE.
RAINFALL AMOUNTS OF ONE TO THREE INCHES WILL BE POSSIBLE IN THE
WATCH AREA...WITH ISOLATED AMOUNTS IN EXCESS OF THREE INCHES. THIS
ADDITIONAL RAINFALL ON ALREADY MOIST SOIL CONDITIONS COULD RESULT IN
FLASH FLOODING.

A FLASH FLOOD WATCH MEANS RAPIDLY RISING WATER OR
FLOODING IS POSSIBLE WITHIN THE WATCH AREA. IF YOU ARE IN THE WATCH
AREA...CHECK PREPAREDNESS REQUIREMENTS...KEEP INFORMED...AND BE READY
FOR QUICK ACTION IF FLASH FLOODING IS OBSERVED OR A WARNING IS
ISSUED.

EMERGENCY MANAGEMENT AND SPOTTER ACTIVATION IS NOT ANTICIPATED
THROUGH MONDAY.

.OUTLOOK FOR THE PERIOD MONDAY THROUGH WEDNESDAY...

THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE
PERIOD.

SHUMWAY