####018004300####
FXUS63 KILX 091115
AFDILX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
515 AM CST MON FEB 9 2009

.DISCUSSION...
ISSUED 307 AM CST MON FEB 9 2009

VERY LITTLE IN THE WAY OF CHANGE IN THE FORECAST THIS MORNING. 
RATHER AGGRESSIVE WAVE KICKING OUT OF THE SRN PLAINS THIS 
MORNING...PUSHING CLOUDS INTO CENTRAL ILLINOIS WELL AHEAD OF THE 
NEXT ROUND OF PRECIPITATION. S/SERLY WINDS AT THE SFC PROVIDING 
PLENTY OF LLVL MOISTURE...AND VISIBILITIES ARE STRUGGLING THIS 
MORNING...KEPT FROM REALLY GETTING OUT OF CONTROL BY THE WEAK WAA AT 
THE SFC THAT IS ACCOMPANYING THE WARMER AIR. PLENTY OF MOISTURE IN 
THE BOUNDARY LAYER FOR THE RAIN TO DEVELOP LATER...WHICH IS THE 
FIRST ISSUE FOR THE FORECAST...FOLLOWED BY THE NEXT SYSTEM TOMORROW 
NIGHT AND INTO WEDNESDAY. MODELS ARE DOING RATHER WELL...AND HAVE 
KEPT TO A MORE NAM/ECMWF SOLUTION. PROBLEM FOR THE MODEL RUNS IS 
STILL TIMING...FLIPPING BETWEEN EARLIER AND LATER STILL. THIS 
PARTICULAR RUN IS MUCH QUICKER WITH THE LATER SYSTEM... AND HAVE 
ADJUSTED THE FORECAST AS SUCH SINCE IT WAS NOT FAR OFF FROM THE 12Z 
RUNS.

SHORT TERM...TODAY AND TOMORROW...
ONSET OF THE PRECIP TODAY IS THE FIRST MAJOR ISSUE WITH THE 
FORECAST. THE GFS IS A BIT MORE DIFFUSE WITH THE MORNING PRECIP AND 
BRINGS IT INTO WESTERN ILLINOIS BEFORE 18Z. THE NAM/WRF DELAYS IT BY 
ABOUT 6 HOURS...AND WOULD NORMALLY BE MORE INCLINED TO FOLLOW THE 
LATER AND MORE CONSERVATIVE NAM/WRF...EXCEPT THAT THE ECMWF HAS 
PRECIP WELL IN BEFORE THAT...MORE ASSOCIATED WITH THE GENERAL TREND 
OF THE FA THAT IS CURRENTLY GOING ON. THOUGH THE WIND HAS AN 
EASTERLY COMPONENT TO IT... IT SEEMS TO BE FEEDING WARMER AND 
MOISTER AIR INTO THE REGION INSTEAD OF INHIBITING. NOT TO MENTION 
THAT PLENTY OF LOW LEVEL CLOUDS ARE ALREADY IN PLACE. SEEMS TO ERR 
ON THE SIDE OF A SOONER START TO THE PRECIP MIGHT BE WARRANTED... IF 
ONLY IN THE FAR WEST. AS A RESULT... LEFT THE LIGHT POPS IN THERE 
BEFORE NOON. BETTER CHANCES THIS AFTERNOON AND TONIGHT...WITH 
THUNDER IN THE FORECAST WITH THE MUCH WARMER TEMPS AND BETTER 
INSTABILITY. MODELS HAVE SPED UP THIS SYSTEM AS WELL...PUSHING THE 
MAJORITY OF THE SHOWERS THROUGH BY MIDNIGHT. GRIDS REFLECT AS MUCH 
WITH ONLY SOME LINGERING SHOWERS IN THE SE AFTER 06Z.  
 
TOMORROW A BRIEF RESPITE FOR THE MORNING...THEN ANOTHER SYSTEM MOVES 
THROUGH CENTRAL ILLINOIS...WITH THE SFC LOW VERY MUCH IN THEN 
NEIGHBORHOOD...TRACKING THROUGH THE CWA. WHEREAS SOME WAA ACTIVITY 
WILL START IN THE EVENING HOURS IN THE SW...THE BEST CHANCES SHOULD 
BE AFTER MIDNIGHT FOR THE REST OF THE FA...AND INTO WED MORNING.

LONG TERM...WEDNESDAY THROUGH FRIDAY...
RAIN AND THUNDER THROUGH WEDNESDAY AGAIN...COMING TO AN END WED 
NIGHT. FORECAST FOR SFC TEMPS TO DROP BELOW FREEZING LATE WED 
NIGHT/THURSDAY MORNING. WITH MODELS ACCELERATING THE EXIT OF PRECIP 
FROM THIS SYSTEM... AM A LITTLE HESITANT TO PUT IN TOO MUCH OF THE 
ACCUMULATING SNOW THAT HPC HAS BEEN HINTING FOR. NOT JUST YET. WANT 
TO GET A BETTER GRIP ON THE EXIT OF THE STORM BEFORE THE 
ACCUMULATIONS MAKE THE FORECAST. THURSDAY SLOWS BACK DOWN A BIT 
BEFORE YET ANOTHER LOW MOVES OUT OF THE SW AGAIN FRIDAY EVENING.

HJS
&&

.AVIATION...
ISSUED 515 AM CST MON FEB 9 2009

WARM FNT FM CNTL MO INTO SRN IL WL MOVE NWD AND BE N OF THE CNTL IL 
TERMINALS BY 18Z. INITIAL MVFR CIGS AND/OR VSBYS WL IMPROVE AS THE 
WARM FNT PASSES AND VFR CONDS WL THEN PREVAIL...ALTHOUGH A DENSE 
MID/HI LVL CIG WILL CONT. STG SLY SFC WNDS WL BE COMMON WITHIN THE 
WARM SECTOR WITH SUSTAINED SPEEDS 20-25 KT AND GUSTS TO 35 KT. A 
SHARP UPR SHORTWAVE NOW OVR THE SRN PLAINS WL MOVE RAPIDLY NEWD TDY 
WITH SHWRS/TSTMS INCRSG AS IT APCHS. EXPECT ABT A 4HR PD OF PCPN FOR 
ANY GIVEN TERMINAL...BEGINNING AT SPI AROUND 22Z AND ADVANCING TO 
CMI BY 00Z TUE. ALTHOUGH THUNDER WL NOT BE AS WIDESPREAD AS THE 
RAIN...THE EXPECTED COVERAGE JUSTIFIES A TEMPO GROUP FOR TS. AFTER 
THE PCPN ENDS...THERE SHOULD BE ANOTHER COUPLE HRS OF MVFR CIGS 
BEFORE THE LOW CLDS CLR OUT AFT 06Z TUE...ALTHOUGH SLY SFC WNDS 
AROUND 15 KT WILL CONT THRU THE END OF THE TAF PD.

04
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$



####018007230####
FXUS64 KMEG 091117
AFDMEG

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
517 AM CST MON FEB 9 2009

...SEVERE THUNDERSTORMS AND HIGH WINDS EXPECTED LATE TUESDAY
AFTERNOON THROUGH MIDDAY WEDNESDAY ACROSS THE MIDSOUTH...

.DISCUSSION...

A WINDY/STORMY WEATHER PATTERN CAN BE EXPECTED TODAY THROUGH
WEDNESDAY. BIGGEST CHALLENGES ARE SEVERE THUNDERSTORMS AND WIND 
POTENTIAL DURING THIS TIME FRAME.

LATEST MODELS WERE IN GOOD GENERAL AGREEMENT FOR THE NEXT SEVERAL
DAYS WITH ONLY MINOR DIFFERENCES IN DETAIL. THE 00Z GFS MODEL
SEEMED TO BE PERFORMING BETTER THAN MOST OTHER MODELS...THOUGH
ALSO LIKED THE 00Z ECMWF MODEL AS WELL.

AT 5 AM CST ACROSS THE FORECAST AREA...DRY AND PARTLY TO MOSTLY
CLOUDY CONDITIONS WERE OCCURRING WITH HIGH THIN CIRRUS MOVING
OVERHEAD. TEMPERATURES WERE WELL ABOVE NORMAL...RANGING FROM 47 AT
LEXINGTON TN TO 56 AT MEMPHIS TN. A LOW PRESSURE DISTURBANCE OVER
WESTERN OKLAHOMA AND NORTH TEXAS WAS QUICKLY MOVING NORTHEAST AND
APPROACHING THE AREA.

TODAY WILL BE WINDY AND WARM DAY. INCREASED WIND SPEEDS IN WIND
ADVISORY...PARTICULARLY OVER NE AR AND MO BOOTHEEL WHERE GUSTS MAY
APPROACH 50 MPH THIS AFTERNOON AS PRESSURE GRADIENT TIGHTENS AHEAD
OF THE LOW PRESSURE DISTURBANCE. WOULD NOT BE SURPRISED IF
ADVISORY NEEDED TO BE EXPANDED A BIT FARTHER EAST. SEE NO REASON
HIGHS WILL NOT REACH THE LOWER TO MID 70S ACROSS THE AREA WITH
EXCELLENT MIXING AND ABUNDANT MORNING SUN.

RAIN CHANCES WILL INCREASE THIS AFTERNOON WEST OF INTERSTATE 55 
AS THE LOW PRESSURE SYSTEM APPROACHES. A NARROW BAND OF SHOWERS
AND PERHAPS THUNDERSTORMS MAY OCCUR ALONG IT. THERE IS THE
POSSIBILITY A COLD POOL MAY DEVELOP WITH THE BAND OF
SHOWERS/STORMS AND PRODUCE SOME ADDITIONAL GUSTY WINDS...BUT THESE
SHOULD REMAIN SEVERE LIMITS...LESS THAN 58 MPH. PREFERRED THE 
00Z GFS MODEL/MAVMOS FOR RAIN CHANCES THIS AFTERNOON.

TONIGHT...RAIN CHANCES WILL INCREASE ACROSS MUCH OF THE AREA AS
THE DISTURBANCE LEAVES A LOW LEVEL MOISTURE CONVERGENCE BOUNDARY
BEHIND...ACROSS THE AREA. KEPT HIGH RAIN CHANCES OVER MUCH OF THE
AREA...ABOVE 50 PERCENT...FOR SHOWERS AND PERHAPS A RUMBLE OR TWO
OF THUNDER. NO SEVERE WEATHER IS EXPECTED WITH WEAK INSTABILITY
AND WEAKENING WINDS. RAINFALL OF 0.10 UP TO 0.50 INCH IS POSSIBLE.
MOIST CONDITIONS WILL PREVAIL ALONG WITH MILD TEMPERATURES IN THE
MID TO UPPER 50S FOR LOWS.

TUESDAY MORNING THROUGH EARLY AFTERNOON...THE MOISTURE CONVERGENCE
BOUNDARY WILL REMAIN OVER THE AREA...PROBABLY NEAR OR JUST SOUTH
OF INTERSTATE 40...SO SCATTERED SHOWERS CAN BE EXPECTED ALONG IT.
MOSTLY CLOUDY SKIES WILL PREVAIL WITH TEMPERATURES WARMING INTO
LOWER 70S.

LATE TUESDAY AFTERNOON AND TUESDAY NIGHT...SEVERE POTENTIAL WILL
INCREASE WEST OF A PARIS TN TO OXFORD MS LINE...PARTICULARLY WEST
OF THE MS RIVER. NOW MORE CONCERNED ABOUT TORNADO POTENTIAL AS
LATEST MODELS IN GOOD AGREEMENT ON STORMS DEVELOPING ON THE
LEFTOVER MOISTURE BOUNDARY WHICH DEVELOPS INTO A WARM FRONT. THIS
WARM FRONT LIFTS NORTH DURING THE EVENING HOURS...ALLOWING MUCH
OF THE AREA TO GET INTO THE WARM SECTOR.

THERE MAY BE AN ENHANCED RISK AREA ACROSS NORTHEAST AR AND MO
BOOTHEEL BETWEEN 3 PM TUESDAY AND 6 AM WEDNESDAY WHERE SUPERCELLS
MAY DEVELOP NEAR THE NORTHWARD ADVANCING WARM FRONT AND AHEAD OF
THE DEVELOPING SQUALL LINE/COLD FRONT. IN THIS AREA...INSTABILITY
WILL BE BEST...LIFTED INDICES -2 TO -4...SBCAPES 300-800
J/KG...PRESSURE/HEIGHT FALLS WILL BE GREATEST...AND BEST DYNAMICS 
WITH HIGHEST SHEAR AND HELICITY WILL BE. A FEW TORNADOES...DAMAGING
WINDS...AND HAIL WOULD BE THE MAIN HAZARDS. CANNOT RULE OUT HEAVY
RAINFALL OF 1 TO 2 INCHES AS WELL. WILL MONITOR TO SEE IF THIS
ENHANCED RISK OCCURS OVER NE AR AND MO BOOTHEEL.

ACROSS THE REST OF THE MIDSOUTH TUESDAY NIGHT...WINDY AND WARM
CONDITIONS WILL PREVAIL WITH MOST SHOWERS AND STORMS MAINLY
STAYING NE OF MEMPHIS NEAR THE WARM FRONT AS MID LEVEL CAPPING
SHOULD LIMIT THE NUMBER OF STORMS. WINDS WILL INCREASE THROUGH THE
NIGHT AND EXCEED WIND ADVISORY CRITERIA.

WEDNESDAY MORNING...THE MAIN SQUALL LINE/FRONT WILL QUICKLY MOVE
THROUGH THE AREA FROM EASTERN AR AROUND 6 AM TO THE MS/AL AND TN
RIVER BY NOON CST. WIDESPREAD DAMAGING WINDS OF 60 MPH APPEAR
LIKELY ALONG THE FRONT/SQUALL LINE. INTERESTINGLY...THE STRONGEST
WINDS MAY ACTUALLY BE AHEAD AND JUST BEHIND THE SQUALL LINE/FRONT
WITH A STRONG PRESSURE GRADIENT IN PLACE. TORNADOES APPEAR TO BE
LESS LIKELY ALONG THE ACTUAL SQUALL LINE AS MOISTURE DEPTH WILL BE
LIMITED AS DRY SLOTTING WILL BE OCCURRING ALOFT. WINDY CONDITIONS
WILL PREVAIL...EVEN BEHIND THE SQUALL LINE/FRONT...SO WIND
ADVISORIES WILL BE NEEDED.

BY WEDNESDAY AFTERNOON...THE SEVERE WEATHER AND HIGH WIND THREAT
WILL DIMINISH AS THE LOW PRESSURE SYSTEM QUICKLY DEPARTS. WINDS
WILL SLOWLY DIMINISH AND SKIES WILL CLEAR SOME...ESPECIALLY SOUTH
WHERE A MID LEVEL DRY SLOT WILL BE. THERE IS A SMALL CHANCE THAT
A FEW SHOWERS/THUNDERSTORMS MAY DEVELOP UNDER THE UPPER LEVEL
TROUGH/LOW NORTH OF INTERSTATE 40 WHICH COULD PRODUCE SMALL HAIL.
CONFIDENCE OF THIS REDEVELOPMENT APPEARS LOW.

THURSDAY THROUGH SUNDAY...AN ACTIVE/WETTER PATTERN APPEARS TO BE
SHAPING UP WITH THE SUBTROPICAL JET AND DEEP MOISTURE NEARBY. A
BRIEF DRY AND COOLER DAY CAN BE EXPECTED THURSDAY BEFORE RAIN
CHANCES INCREASE FRIDAY. ANOTHER SYSTEM MAY ARRIVE ON SUNDAY.
NOT EXPECTING ANY SEVERE WEATHER DURING THIS TIME FRAME AT THIS
TIME. TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL.

MBS

&&

.AVIATION...

06Z TAFS 

MID/HIGH LEVEL CLOUDS OVERSPREADING TAF SITES AS LOW NEAR THE
TEXAS PANHANDLE MOVES NORTHEAST INTO THE CENTRAL PLAINS INTO
MONDAY. SOUTHEAST WINDS WILL INCREASE TO AROUND 10-12 KTS
TOWARDS SUNRISE AND VEER TO THE SOUTH LATE MONDAY MORNING AFTER 16Z
WITH SUSTAINED WINDS BETWEEN 15 TO 20 KTS AND GUSTS BETWEEN 25 TO
30 KTS CONTINUING AT LEAST THROUGH 10/00Z. RAIN SHOWERS MAY BEGIN
AT JBR AS EARLY AS 21Z WITH BEST CHANCES OF RAIN SHOWERS HOLDING
OFF UNTIL AFTER 00Z AT JBR. RAIN CHANCES AT MKL/MEM NOT EXPECTED
TO ARRIVE UNTIL AFTER 04-05Z. VFR CEILINGS EXPECTED AT ALL SITES
THROUGH AT LEAST 00Z BUT WILL GRADUALLY LOWER TO MVFR CONDITIONS
AFTER 00Z AT JBR AND 04Z AT MEM.

CJC

&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  74  58  72  60 /  40  80  70  90 
MKL  73  57  71  60 /  10  70  70  70 
JBR  71  55  71  57 /  60  70  60  90 
TUP  74  57  74  60 /  10  40  50  50 

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM CST THIS AFTERNOON 
     FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
     MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.

MO...WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM CST THIS AFTERNOON 
     FOR DUNKLIN-PEMISCOT.

MS...WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM CST THIS AFTERNOON 
     FOR COAHOMA-DESOTO-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA-
     YALOBUSHA.

TN...WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM CST THIS AFTERNOON 
     FOR DYER-LAKE-LAUDERDALE-OBION-SHELBY-TIPTON.

&&

$$