Severe Thunderstorm Warning 5, NWS Springfield, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
320 AM CST SUN FEB 13 2000

FORECAST CONCERN:  SVR WEATHER THREAT TODAY

LATEST SFC ANALYSIS PLACES BROAD SFC LOW S OF ICT...NOTABLY FURTHER
NORTH THAN ALL OF THE 00Z MODEL RUNS...EXCEPT THE NGM. SFC WARM
FRONT SNAKES SE TO JUST SOUTH OF THE MO BORDER...AND HAS RESULTED IN
SOME DENSE ADVECTION FOG ACROSS THE SERN PORTION OF THE CWA. BEST
LOW LEVEL MOISTURE FIELDS STILL CONFINED SOUTH OF A STNRY FRONT
LOCATED ALONG THE GULF COAST...BUT EXPECT A NEWD SURGE TODAY AS SRLY
FLOW INCREASES AHEAD OF SFC LOW.

THE TRACK OF THE SFC LOW AND PLACEMENT OF THE WARM FRONT WILL PLAY A
KEY FACTOR IN THE SVR POTENTIAL THIS AFTN. CURRENT RADAR MOSAIC
SHOWS DECENT RETURNS ALOFT OVER ERN KS...ASSOCIATED WITH 850 MB
MOIST AXIS. AS THIS MOIST AXIS SWINGS EAST AHEAD OF PROGRESSIVE
MID/UPR LVL SHORTWAVE...SHOULD BEGIN TO SEE CONVECTION INTENSIFY
ACROSS AR AND SPREAD NE INTO SERN ZONES THIS MORNING. ALREADY A FEW
ELEVATED STORMS FIRING SE OF WEST PLAINS ABOVE DENSE FOG. MODIFICATION
OF 00Z SGF SNDG...ACCOUNTING FOR STRONG WAA ALOFT ABOVE STABLE
SFC-850MB LYR...SUGGESTS POTENTIAL FOR ELEVATED DEEP CONVECTION TO
DEVELOP. MODEL FCST SNDGS SUGGEST BEST INSTABILITY OCCURS S AND E OF
SGF. WITH DECENT 30-40 KT LLJ AXIS AND VERY LOW WET-BULB ZEROS
AROUND 7000 FT...POTENTIAL FOR LARGE HAIL EXISTS OVER SE PORTION OF
THE CWA. AGREE WITH CURRENT PLACEMENT OF SLGT RISK...AND WILL
HIGHLIGHT ZONES WITH SVR POTENTIAL AND HAIL.

WILL LOWER POPS ACROSS NRN AND WRN ZONES FOR TODAY AND DROP MENTION
OF TSRA...AS BEST CHC FOR CONVECTION WILL AGAIN BE CONFINED TO SE
ZONES WITH STORM PROPAGATION TO THE NE. MODELS HAVE BACKED OFF
SIGNIFICANTLY FROM PRVS RUNS ON POPS AND QPF...AND TEND TO AGREE
WITH LACK OF DEEP MOISTURE AND STABLE ENE FLOW N OF THE SFC LOW.

TRACK OF SFC LOW WILL ALSO WREAK HAVOC ON TEMPS TODAY. COULD EASILY
SEE A 15-20 DEGREE SPREAD FROM NW TO SE THIS AFTERNOON AS NGM/RUC TAKE
LOW DUE EAST ACROSS SGF. ANY CHANCE FOR SUN WILL BE CONFINED TO SRN
TIER...AND WILL BE FURTHER LIMITED BY CONSIDERABLE MID-HIGH LVL
AS/CS.

GUIDANCE TEMPS LOOK OK FOR TONIGHT AS CAA WRAPS IN BEHIND SFC LOW.
WILL LIKELY SEE COLD AIR SC DEVELOP ACROSS THE CWA OVERNIGHT...WITH
BKN-OVC EXPECTED THRU EARLY MONDAY AS POST-FRONTAL TROF LINGERS
ACROSS THE AREA. WILL KEEP MENTION OF FLURRIES ACROSS NE ZONES FOR
TONIGHT.

SFC RIDGE AXIS SLIDES ACROSS THE AREA MONDAY...AS PROGRESSIVE
PATTERN CONTINUES. WL SEE CLEARING ACROSS WRN ZONES WITH ALL MODELS
INDICATING STRONG SUBSIDENCE. TEMPS SHOULD REBOUND TO NEAR 50 IN KS
ZONES...BUT SHARP 850 THERMAL GRADIENT IN RESPONSE TO CAA AND
LINGERING LOW LEVEL MOISTURE SHOULD PRECLUDE WARMING AND MUCH IN THE
WAY OF CLEARING ACROSS NE SECTIONS.

IN THE EXTENDED...SRLY FLOW QUICKLY RETURNS MONDAY NIGHT AS RIDGE
AXIS MOVES EAST. SHOULD BE A VERY PLEASANT FEBRUARY DAY ON TUESDAY
WITH TEMPS INTO THE 60S AS WAA DEVELOPS AHEAD OF WEAK SFC LOW OVER
WRN OK. REMAINS MILD THROUGH THURSDAY..BUT SLIGHTLY COOLER AS A DRY
FRONTAL PASSAGE OCCURS SOMETIME LATE TUESDAY.

PRELIM CCF (FOR COORDINATION ONLY):

SGF WB 051/028 046/038 065 144100
JLN CB 049/029 050/03F9 068 143100
VIH WE 047/028 043/033 063 1463-0
UNO TE 055/030 047/035 065 149200

.SGF...NONE

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