Flash Flood Warning 28, NWS Lincoln, IL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
650 AM CDT FRI MAY 31 2013

.DISCUSSION...
ISSUED 325 AM CDT FRI MAY 31 2013

SHORT TERM...TODAY THROUGH SUNDAY

07Z SURFACE MAP SHOWED LITTLE CHANGE FROM 24 HRS AGO WITH A LOW
PRESSURE COMPLEX STRETCHED ALONG THE PLAINS...WITH THE DOMINANT
LOW OVER NORTH CENTRAL SD. ALOFT A VIGOROUS CLOSED LOW AT 500 MB
WAS SPINNING OVER THE DAKOTAS AND SENDING SHORTWAVES EAST INTO THE
MIDWEST. THIS SPARKED SEVERE STORMS LAST NIGHT AND CONTINUES TO
PRODUCE LOCALLY HEAVY RAIN OVER THE EASTERN CWA EARLY THIS
MORNING. ANOTHER SHORTWAVE SLIDING INTO THE KS/NEB BORDER REGION
IS ALREADY IGNITING ANOTHER ROUND OF THUNDERSTORMS IN NE KS. WITH
SUPPORT FROM A 40-50 KT SW LLJ THIS COMPLEX IS EXPECTED TO GROW
UPSCALE THROUGH THIS MORNING AND REACH INTO WESTERN IL AROUND
14-15Z. FOR CONVECTIVE TRENDS TODAY HAVE CLOSELY FOLLOWED THE 4KM
NSSL WRF WHICH HAS PERFORMED WELL THE PAST COUPLE DAYS...AND ALSO
LOOKS SIMILAR TO THE 4KM LSX ARW-WRF. THESE MODELS WOULD SUGGEST
THIS COMPLEX AFFECTING THE NORTHWEST HALF OF THE CWA THROUGH
EARLY AFTERNOON...THEN DEVELOPMENT ALONG THE LEADING EDGE OF THE
OUTFLOW AFFECTING THE CENTRAL AND SOUTHERN CWA INTO THIS EVENING.
LOOKING AT SEVERE WX PARAMETERS...45-55 KT 0-6KM BULK SHEAR AND
SURFACE BASED CAPES IN EXCESS OF 2K J/KG WOULD SUPPORT
ORGANIZATION FOR A SQUALL LINE OR QLCS TYPE EVENT. ANY LOCAL
BACKING OF THE SFC FLOW WOULD SUPPORT AN ISOLATED TORNADO THREAT.
OF COURSE THE EVOLUTION OF THE EXPECTED MCS TO OUR WEST WILL BE
KEY TO DEVELOPMENT LATER TODAY...AS A CONVECTIVELY OVERTURNED
AIRMASS AND/OR CAPE REDUCING DENSE OVERCAST MAKE THE SEVERE
TRENDS MORE COMPLICATED. HEAVY RAIN RATES ARE POSSIBLE ONCE
AGAIN...AND WITH 1.5-1.8 INCH PRECIPITABLE WATER THE THE POTENTIAL
FOR TRAINING CELLS HAVE EXPANDED THE FLASH FLOOD WATCH TO COVER
THE ENTIRE CWA RUNNING THROUGH 00Z/SUN.

THE COLD FRONT IS FORECAST TO PUSH ACROSS THE CWA ON SATURDAY AND
PRODUCE ANOTHER ROUND OF LOCALLY HEAVY RAIN AND POSSIBLE SEVERE
STORMS. BASED ON TIMING THE CENTRAL AND EASTERN CWA PRIMARILY EAST
OF I-55 LOOK MOST SUSCEPTIBLE FOR MORE INTENSE ACTIVITY.

THE POST-FRONTAL AIRMASS WILL BRING MUCH COOLER AIR INTO THE
MIDWEST ON SUNDAY. HAVE ADDED A SLIGHT CHANCE OF SHOWERS AS LLVL
MOISTURE LINGERS AND ANOTHER SHORTWAVE ROTATES AROUND THE GREAT
LAKES TROF IN CYCLONIC FLOW.

LONG TERM...MONDAY THROUGH THURSDAY

CANADIAN HIGH PRESSURE SHIFTING ACROSS THE GREAT LAKES IS EXPECTED
TO PRODUCE QUIET AND SEASONABLY COOL WEATHER INTO TUESDAY. HOWEVER BY
MID-WEEK ANOTHER CLOSED MID LEVEL LOW IS FORECAST TO MOVE INTO THE
NORTHERN PLAINS. THIS WILL SPIN UP ANOTHER PLAINS SFC LOW...AND
WARM ADVECTION PRECIP WILL SPREAD EAST ACROSS THE REGION. THIS
LOOKS TO BE ANOTHER SLOW MOVING SYSTEM WITH POPS LINGERING
THURSDAY AND LIKELY BEYOND. SYSTEM SHOULD NOT BE AS INTENSE AS
THE LAST FEW WE HAVE DEALT WITH AS A SUB-TROPICAL RIDGE OVER
NORTHERN MEXICO LIMITS DEEP MOISTURE FEED.

&&

.AVIATION...
ISSUED 644 AM CDT FRI MAY 31 2013
A SLIGHT SHIFT IN THE FORECAST THIS MORNING AS THE HIGH RES MODELS
SHOWING THE PROGRESSION OF A COMPLEX IN NRN MO PUSHING INTO
CENTRAL IL THIS MORNING AND MOVING THE TIME TABLE UP A BIT.
PUTTING TEMPO GROUPS IN FOR THE TIME FRAME SURROUNDING 16Z TO
20Z...LINGERING RAIN A LITTLE LONGER THROUGH CENTRAL IL...THEN
DRIVING PRECIP SOUTH. TROUBLE STILL REMAINS WITH THE POTENTIAL FOR
THE ATMOSPHERE TO RECOVER AND REFIRE LATER IN THE EVENING WITH
ANOTHER ROUND. SINCE 4KM MODELS STARTING TO LOOK WORKED
OVER...HAVE OPTED FOR A SIMPLE VCTS MENTION THROUGH THE AFTERNOON.
FOR NOW...CIGS MOSTLY IN THE VFR EXCEPT WITH THE TS. BRISK
SOUTHERLY WINDS YET AGAIN WITH STOUT GUSTS TO 28-30KT.

HJS
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR ILZ027>031-
036>038-040>057-061>063-066>068-071>073.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
625 AM CDT FRI MAY 31 2013

ILZ027>031-036-037-040-041-047>050-011100-
CASS-FULTON-KNOX-MARSHALL-MASON-MENARD-MORGAN-PEORIA-SCHUYLER-
SCOTT-STARK-TAZEWELL-WOODFORD-
625 AM CDT FRI MAY 31 2013

...FLASH FLOOD WATCH IN EFFECT THROUGH SATURDAY EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS.

.DAY ONE...TODAY AND TONIGHT

ANOTHER DAY OF THUNDERSTORMS FOR CENTRAL ILLINOIS. THIS
AFTERNOON...THUNDERSTORMS WILL MOVE THROUGH CENTRAL ILLINOIS
LATER THIS AND MAY BECOME SEVERE...PRODUCING DAMAGING
WINDS...LARGE HAIL...AND ISOLATED TORNADOES. ANOTHER INCH OR TWO
OF RAIN TODAY AND TONIGHT WILL CONTRIBUTE TO THE ONGOING THREAT OF
FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

PERIODS OF THUNDERSTORMS ARE EXPECTED SATURDAY AS WELL. MAJORITY
OF THE SEVERE WEATHER SHOULD BE TO THE SOUTHEAST...THOUGH HEAVY
RAINS WILL CONTINUE TO THREATEN WITH FLASH FLOODING.

FLOODING WILL CONTINUE ALONG THE SPOON RIVER THROUGH MONDAY OR
TUESDAY. RIVER LEVELS WILL CONTINUE TO RISE ALONG THE ILLINOIS
RIVER AS WELL...WITH ALL POINTS FROM HENRY DOWNSTREAM GOING ABOVE
FLOOD STAGE FROM FRIDAY INTO NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED FROM MIDDAY THROUGH THE
AFTERNOON.

ILZ038-042>046-051>057-061>063-066>068-071>073-011130-
CHAMPAIGN-CHRISTIAN-CLARK-CLAY-COLES-CRAWFORD-CUMBERLAND-DE WITT-
DOUGLAS-EDGAR-EFFINGHAM-JASPER-LAWRENCE-LOGAN-MACON-MCLEAN-
MOULTRIE-PIATT-RICHLAND-SANGAMON-SHELBY-VERMILION-
625 AM CDT FRI MAY 31 2013

...FLASH FLOOD WATCH IN EFFECT THROUGH SATURDAY EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS...EAST CENTRAL ILLINOIS AND SOUTHEAST ILLINOIS.

.DAY ONE...TODAY AND TONIGHT

ANOTHER DAY OF THUNDERSTORMS FOR CENTRAL ILLINOIS. THIS
AFTERNOON...THUNDERSTORMS WILL MOVE THROUGH CENTRAL ILLINOIS
AND MAY BECOME SEVERE...PRODUCING DAMAGING WINDS...LARGE
HAIL...AND ISOLATED TORNADOES. ANOTHER INCH OR TWO OF RAIN TODAY
AND TONIGHT WILL CONTRIBUTE TO THE ONGOING THREAT OF FLASH
FLOODING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

PERIODS OF THUNDERSTORMS ARE SATURDAY AS WELL. SOME OF THE STORMS
COULD BECOME SEVERE ON SATURDAY...WITH DAMAGING WINDS AND LARGE
HAIL THE MAIN THREATS. EARLY INDICATIONS SUGGEST TOTAL RAINFALL
AMOUNTS OF ANOTHER INCH OR SO WILL BE POSSIBLE SATURDAY...WITH
ISOLATED HIGHER AMOUNTS WITHIN STRONGER STORMS. THE THREAT OF
SEVERE STORMS SHOULD DIMINISH WEST OF THE ILLINOIS RIVER ON
SATURDAY.

FLOODING WILL CONTINUE ALONG THE SPOON RIVER THROUGH MONDAY OR
TUESDAY. RIVER LEVELS WILL CONTINUE TO RISE ALONG THE ILLINOIS
RIVER AS WELL...WITH ALL POINTS FROM HENRY DOWNSTREAM GOING ABOVE
FLOOD STAGE FROM FRIDAY INTO NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED FROM MIDDAY...INTO THIS
EVENING.

HJS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
811 AM CDT FRI MAY 31 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

&&

OUSLEY

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
824 AM CDT FRI MAY 31 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0745 AM     HEAVY RAIN       9 S MARSHALL            39.27N 87.69W
05/31/2013  M1.31 INCH       CLARK              IL   MESONET

            SWOP REPORT FOR WEST UNION 1W.

&&

OUSLEY