AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
215 PM CST FRI MAR 14 2003
THREAT FOR SIGNIFICANT SEVERE WEATHER EPISODE MONDAY AND TUESDAY
CONTINUES TO HIGHLIGHT THE MAIN FORECAST CONCERNS THIS PERIOD.
LONGER TERM: AS STRONG UPPER LEVEL RIDGE SLIDES ACROSS THE REGION
THIS WEEKEND...ALL EYES WILL BE FOCUSED ON A MAJOR STORM SYSTEM AND
ATTENDANT UPPER LEVEL JET ENERGY THAT IS PRESENTLY APPROACHING THE
WEST COAST. FOR OVER A WEEK NOW...MEDIUM RANGE AND NOW SHORT RANGE
SOLUTIONS HAVE BEEN CONSISTENT WITH RAPID DEVELOPMENT OF A VIGOROUS
UPPER LEVEL SYSTEM OVER THE GREAT BASIN AS AN UNSEASONABLY STRONG
JET STREAM SPLITS WITH THE SOUTHERN STREAM TAKING THE BRUNT OF THE
ENERGY.
AHEAD OF THIS SYSTEM...WATER VAPOR IMAGERY DEPICTS A WELL DEFINED
SHORTWAVE ALONG THE ARIZONA/MEXICAN BORDER THAT WILL APPROACH THE
AREA ON SUNDAY. ALTHOUGH THE BRUNT OF THIS SYSTEM WILL MOVE EAST
ALONG THE GULF COAST...ETA/GFS HEIGHT FIELDS INDICATE ENOUGH OF A
SHORTWAVE WEAKNESS THAT MAY BE SUFFICIENT TO BREAK THE CAP SUNDAY
AFTERNOON ACROSS WRN MO/SE KS...AND THEREFORE HAVE INTRODUCED
SCATTERED STORMS FROM THEN INTO THE EVENING HOURS.
ON MONDAY...UPPER LOW WILL CONTINUE TO DEEPEN AND BECOME NEGATIVELY
TILTED AIDED BY FAVORABLE JET POSITION AND STRONGLY DIFFLUENT UPPER
FLOW ACROSS THE CENTRAL US. RAPID LEE CYCLOGENESIS AND STRONG GULF
INFLUX OF MOISTURE WILL SET THE STAGE FOR WHAT WILL LIKELY BE AN
IMPRESSIVE SEVERE WEATHER OUTBREAK ACROSS THE NATION'S MID SECTION
LATE MONDAY AS INCREASING LOW LEVEL MOISTURE AND VERY FAVORABLE
SHEAR PROFILES ARE IGNITED BY APPROACHING FRONTAL SYSTEM/DRY LINE.
UNFORTUNATELY...LACK OF A UPSTREAM KICKER WILL LIKELY CAUSE UPPER
LEVEL STORM SYSTEM TO CLOSE AND CUT OFF ACROSS THE NORTHERN PLAINS
WHILE A SECOND UPPER LEVEL SYSTEM ROTATES UNDERNEATH. DRY SLOT
ASSOCIATED WITH FIRST MAJOR SYSTEM COULD ONLY HELP FUEL WHAT WILL
LIKELY BE A SECOND ROUND OF SEVERE WEATHER ON TUESDAY AS SECONDARY
SURFACE LOW DEVELOPMENT TAKES PLACE ACROSS THE MIDWEST. HOPEFULLY...
THIS ACTIVITY WILL REGENERATE EAST OF THE CWA...BUT CANNOT RULE THIS
OUT ENTIRELY GIVEN EXPECTED VERY SLOW PROGRESSION OF THE OVERALL
LONGWAVE PATTERN AND MODEL TREND IN THIS DIRECTION. WITH THAT
SAID....HAVE MAINTAINED LIKELY POPS MONDAY NIGHT AND EXTENDED THEM
INTO TUESDAY ACROSS CENTRAL/S CENTRAL MO. HAVE ALSO UPPER
TEMPERATURES TUESDAY THINKING THAT DRY SLOTTING WILL LEAD TO SOME
SUNSHINE COMBINED WITH PREVAILING WESTERLY FLOW OVER THE AREA.
I will posting more info. here from various outlets throughout the weekend.