Large Outbreak Of Tornadoes Forecasted Today

Heads up everyone. The storm system is finally pulling out and it is going to give us one last show. Today is the last day but could be the worst of them all.

STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWNS.

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 WNW LUK 20 ENE OWB 10 SW DYR 10 WSW PBF 25 WSW HOT FSM 45 NW SGF 50 S P35 20 ESE RFD 25 S AZO 35 E FWA 20 WNW LUK.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 SW BUF IPT 20 ESE NEL ...CONT... 25 ESE ILM 30 SW GSO 25 WSW TYS 15 ENE JAN 50 NNW BPT 35 NNW NIR 30 W HDO 40 N JCT 50 NW MWL 25 E PNC 20 W TOP 15 ENE DSM 20 SSW VOK 45 NNW MBL 25 NE OSC.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 NNW FCA 35 ENE BTM 15 ESE WRL 20 SE GRI 25 SW FOD 25 WNW LSE 15 NNE MQT ...CONT... 25 NE ROC 15 SE ISP ...CONT... 35 ENE CRE 30 ESE CLT SPA 60 NNW AHN 45 ESE MEI 20 ENE BPT 15 E CRP ...CONT... 25 NW DRT 45 NNE ABI 40 NE CSM 30 NNE DHT 10 E ALS 50 WNW MLF 35 SSE U31 30 S SVE 35 WSW MHS 25 SSW SLE 50 ENE BLI.

...A POTENTIALLY SIGNIFICANT SEVERE WEATHER DAY POSSIBLE SATURDAY FROM ERN PARTS OF THE SRN PLAINS EWD INTO THE MID MS VALLEY AND PARTS OF THE OH VALLEY AND SERN U.S....

STRONG SHORTWAVE TROUGH AND ASSOCIATED 100+ KT UPPER JET NOW OVER THE SWRN U.S. WILL CONTINUE EWD THROUGH THE SRN PLAINS SATURDAY AND INTO THE MID MS-OH VALLEYS SATURDAY EVENING AND NIGHT. IN RESPONSE TO INCREASING DIVERGENCE ACCOMPANYING THE UPPER JET...SURFACE LOW IS FORECAST TO DEEPEN OVER THE MID MS VALLEY BY TOMORROW EVENING AND LIFT NEWD TOWARD THE GREAT LAKES TOMORROW NIGHT. IN THE PROCESS A COLD FRONT WILL SURGE SEWD THROUGH THE SRN PLAINS AND MERGE WITH THE DRYLINE...THEN CONTINUE EWD THROUGH THE MID MS VALLEY AND SERN U.S. SATURDAY EVENING AND OVERNIGHT.

CLUSTERS OF STORMS WILL LIKELY BE IN PROGRESS FROM PARTS OF THE OH VALLEY EWD INTO THE MID ATLANTIC REGION ACCOMPANIED BY THREAT FOR HAIL AND DAMAGING WIND. THIS ACTIVITY SHOULD LIFT NEWD DURING THE DAY ALLOWING THE WARM SECTOR TO BEGIN TO DESTABILIZE FROM THE SW. RICH LOW LEVEL MOISTURE ALREADY EXISTS IN A LARGE REGION FROM THE SRN PLAINS EWD THROUGH THE SERN U.S. AND OH VALLEY. WITH STEEP LAPSE RATES ALREADY IN PLACE ABOVE THIS MOISTURE...THE ATMOSPHERE SHOULD BECOME VERY UNSTABLE ALONG/E OF THE FRONT FROM ERN PARTS OF THE CNTRL/SRN PLAINS THROUGH THE MS VALLEY. INSTABILITY WILL BE SOMEWHAT LESS TOWARD THE OH VALLEY WHERE LESS HEATING WILL PROBABLY OCCUR.

STORMS ARE EXPECTED TO REDEVELOP ALONG THE DRYLINE FROM PARTS OF ERN KS SWD THROUGH ERN OK AND FARTHER SWD THROUGH N CNTRL AND E CNTRL TX BY MID AFTERNOON AS UPPER DIVERGENCE/LARGE SCALE ASCENT INCREASES AHEAD OF UPPER TROUGH. OTHER STORMS WILL LIKELY DEVELOP IN VICINITY OF TRIPLE POINT AND ALONG WARM FRONT E OF THE SURFACE LOW ACROSS NERN KS NR MO AREA. SHEAR PROFILES WILL FAVOR SUPERCELLS WITH INITIAL STORMS THAT DEVELOP WITH LARGE HAIL LIKELY AND ISOLATED TORNADOES POSSIBLE. TORNADO THREAT MAY BE SOMEWHAT HIGHER OVER PARTS OF THE MID MS VALLEY INCLUDING NRN MO WHERE THE LOW LEVEL JET WILL INTERSECT BACKING FLOW NEAR THE SURFACE E OF DEEPENING LOW. LINEAR CONVERGENCE WILL INCREASE WITH TIME AS THE FRONT OVERTAKES THE DRYLINE. THUS ACTIVITY MAY EVENTUALLY EVOLVE INTO LINES CONTAINING EMBEDDED SUPERCELLS CAPABLE OF PRODUCING WIDESPREAD DAMAGING WIND AS WELL AS ISOLATED TORNADOES AS IT SPREADS EWD TOWARD THE OH VALLEY AND SERN U.S. OVERNIGHT.

Sorry for the caps but that is how they make these products

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
440 AM CDT SAT MAY 10 2003

SIGNIFICANT OUTBREAK OF SEVERE WEATHER EXPECTED FOR PORTIONS OF THE CWA THIS AFTERNOON AND EVENING. DETAILS TO FOLLOW...BUT PER COORDINATION WITH SPC (THANKS!) THEY WILL BE UPGRADING TO HIGH RISK IN FAR SOUTHEAST. DANGEROUS SITUATION WITH POTENTIAL FOR SEVERAL TORNADOES OF WHICH A COUPLE COULD BE MODERATE TO STRONG IN INTENSITY WITH LONG TRACKS. WILL BE DOING AN 18Z UPPER AIR RELEASE. EXPECT SEVERE WEATHER WATCHES TO BE ISSUED BY MID AFTERNOON.

EARLIER CONVECTION WHICH PRODUCED SOME GUSTY WINDS AND A FEW HAIL REPORTS OF UP TO NICKEL SIZE HAS WEAKENED AND MOVED WELL OFF TO THE EAST INTO PORTIONS OF THE OHIO VALLEY. NEXT SURGE OF CONVECTION FAST APPROACHING FROM THE SOUTHWEST. SOME WEAKENING IS EXPECTED BUT POTENTIAL STILL EXISTS FOR ISOLATED SEVERE HAIL MAINLY IN THE FAR SOUTH. MAIN SHOW STILL ON TAP FOR LATER THIS AFTERNOON AND EVENING
AS 100-120 KT H3 JET INDUCES STRONG UPPER LEVEL DIVERGENCE
TOWARD 00Z.

LATEST SURFACE ANALYSIS PLACES LOW IN SOUTHWEST KS. EARLIER CONVECTION HAS CONTAMINATED WIND FIELDS SOME...BUT THERMAL/MOISTURE FIELDS INDICATE FRONTAL ZONE EXTENDS EAST/NORTHEAST FROM LOW THROUGH CENTRAL KS INTO WEST CENTRAL IL ROUGHLY FROM JUST SOUTH OF SALINA TO NEAR QUINCY. CONVECTION RE-ENERGIZING FROM PORTIONS OF KS/NE INTO NORTH
CENTRAL MO ON NOSE OF 40-50 KT LLJ AND IN REGION OF STRONG MOISTURE CONVERGENCE. SOME SURFACE BASED CONVECTION ALONG FRONTAL ZONE WHICH WILL BECOME ELEVATED AS IT RACES EAST/NORTHEAST. LLVL NORTH WINDS BRINGING INFLUX OF SOMEWHAT DRIER AIR WITH DEWPTS IN THE U40S/50S...THUS SOME WEAKENING OF CONVECTION IS ANTICIPATED.

EXPECT SOME BREAKS IN THE CLOUDS BEFORE NEXT ROUND OF CONVECTION DEVELOPS THIS AFTERNOON...ROUGHLY IN THE 20Z-21Z TIMEFRAME. UPPER LOW OVER ROCKIES TO EJECT AS NEG TILT WAVE...WHILE SURFACE LOW PROGGED TO MOVE NORTHEAST WITH MODELS IN DECENT AGREEMENT ON PLACEMENT NEAR KIRKSVILLE MO BY 00Z...DEEPENING AND SHIFTING EAST/NORTHEAST TOWARD THE QUAD CITIES DURING THE EVENING TO NEAR LAKE MI 12Z SUN.
MODELS STILL SHOW PRESSURE DROP OF NEARLY 10 MBS IN THIS TIMESPAN...WHICH WILL TRANSLATE INTO MORE VIGOROUS CONVECTION. ATMOSPHERE TO BECOME VERY UNSTABLE IN THE SOUTH/EAST THIS AFTERNOON WITH TEMPS EXPECTED TO BE
PUSHING L80S AND DEWPTS NEAR 70...LI/S OF -4 TO -8...AND CAPES APPROACHING 3000 J/KG. SHEAR IS QUITE IMPRESSIVE THUS HAVE NO REAL CONCERNS OF SEVERE THREAT DIMINISHING SHOULD DEBRIS FROM MORNING CONVECTION HANG ON LONGER THAN EXPECTED. RUNNING BEHIND...BUT FIRST GLANCE AT NICHOLS BLEP TECHNIQUE SUGGESTS LITTLE CHANGE FROM DAY SHIFT COMPUTATIONS.
USING INFLOW OF ROUGHLY 82/70...STRAIGHT LINE POTENTIAL WILL BE 60 KTS WITH ROTATIONAL UPDRAFT VELOCITY OF ABOUT 140 KTS OR SO SUGGESTING TORNADIC STRENGTH OF LOW END F3. IF SURFACE WINDS CAN CLIMB ANOTHER 5-7 KTS AND TEMPS ANOTHER FEW DEGS THEN F4 POTENTIAL. ANTICIPATE SUPERCELLS DEVELOPING IN NORTHEAST MO AROUND 20-21Z. ACTIVITY WILL THEN SHIFT EAST WITH PRESSURE FALLS AND ADVECTION. THIS IS A DANGEROUS SITUATION WITH POTENTIAL FOR ONE OR TWO LONG TRACKED TORNADOES. GREATEST RISK WITH AND JUST EAST OF SURFACE LOW...WHICH WOULD BE ROUGHLY KEOSAUQUA...TO BURLINGTON...TO GALESBURG AND POINTS SOUTH. CAUTION THOUGH AS ANY SLIGHT
DEVIATION IN TRACK OF LOW WILL CHANGE GREATEST RISK AREA. WILL BE UPDATING HWO WITH LATEST INFORMATION AND ATTEMPTING TO NAIL DOWN GREATEST THREAT AREA AND TIMING...ETC. ASIDE FROM POTENTIAL FOR TORNADOES...LARGE HAIL AND DAMAGING WINDS...FLOODING ALSO SOMEWHAT OF A CONCERN.
FFG VALUES STILL 1.5 TO 2.5 INCHES OVER MOST OF THE AREA FOR 3 HRS. WOULDN/T BE SUPRISED TO SEE A FEW 3 INCH AMOUNTS IN SOUTHERN PORTIONS OF CWA...WITH FLOODING LIKELY WITH SUPERCELLS. HOWEVER...DON/T BELIEVE HEAVY RAINS OF THIS MAGNITUDE WILL BE WIDESPREAD ENOUGH TO WARRANT
A FLOOD WATCH. WILL CONTINUE TO HIGHLIGHT HEAVY RAIN IN ZONES AND IN HWO.

SURFACE LOW CONTINUES TO DEEPEN WHILE LIFTING THROUGH THE GREAT LAKES ON SUN. STRONG PRESSURE GRADIENT TO RESULT IN WINDY CONDITIONS WITH STILL SOME POTENTIAL FOR WIND ADVISORY. LOTS OF CLOUDS AND SOME DRIZZLE IN WRAP AROUND WITH CHANCE OF RAIN NORTHERN 1/3RD OR SO. CLOUDS WILL KEEP HOLD TEMPS MAINLY IN THE 50S...SO OVERALL UNFORTUNATELY NOT
THE BEST OF DAYS FOR MOM.

NO CHANGES TO EXTENDED...DUE TO TIME CONSTRAINTS.

DVN...
IA...NONE.
IL...NONE.
MO...NONE.

Potentially Dangerous Situation Developing for Saturday Afternoon and Evening

Super cellular Thunderstorms Producing

Large Hail Up To The Size Of Baseballs
Strong Straightline Winds Gusting over 80 MPH
Strong Tornadoes Nearing F3 to F4 Status

WeatherMatics.com will have the most up to date information on the web through the day tomorrow. This is a PARTICULARLY DANGEROUS SITUATION developing for the ENTIRE area for tomorrow afternoon and tomorrow night. STAY TUNED!

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