MODERATE RISK of Severe Monday ... MO, TX, AR, LA

[Stormsfury]

SPC has issued a moderate risk for severe Wx from Southern MO, all of AR, NE TX, and NW LA for Monday ... and the risk continues Tuesday (as a slight for the Southeast on Tuesday in which GSP has released a disturbing discussion regarding this) ...



...SRN AND CNTRL PLAINS/LOWER MS VALLEY...
SCATTERED CONVECTION WILL LIKELY BE ONGOING ACROSS MUCH OF THE SRN
PLAINS IN RESPONSE TO STRONG FORCING ASSOCIATED WITH AN APPROACHING
UPPER-LEVEL TROUGH. A COLD FRONT WILL ORGANIZE AND MOVE SWIFTLY EWD
ACROSS W TX BY AFTERNOON. CONVECTION SHOULD FOCUS ALONG A PREFRONTAL
TROUGH LOCATED ACROSS CNTRL TX EXTENDING NWD INTO CNTRL OK DURING
THE DAY. AS THE CONVECTIVE LINE MOVES EWD...IT WILL ENCOUNTER
INCREASING SFC MOISTURE WITH SFC DEWPOINTS IN THE MID 60S F ACROSS
NE TX AND SERN OK. ALTHOUGH SFC HEATING WILL BE LIMITED BY
WIDESPREAD CLOUD COVER...MLCAPE VALUES SHOULD REACH 500 TO 1000 J/KG
ACROSS THE ARKLATEX REGION. THE LINE SHOULD ORGANIZE AS IT MOVES EWD
INTO INCREASING INSTABILITY DURING THE EVENING HOURS. THE AMOUNT OF
INSTABILITY THAT MATERIALIZES WILL DETERMINE THE AMOUNT OF SEVERE
WEATHER COVERAGE. STRONG DEEP LAYER SHEAR WITH 0-6 KM SHEAR AROUND
50 KT WILL ENHANCE A WIND DAMAGE POTENTIAL ESPECIALLY WITH BOWING
SEGMENTS WITHIN THE LINE. IN ADDITION...STRONG 0-1 KM SHEAR AND LOW
LCL HEIGHTS WILL FAVOR AN ISOLATED TORNADO THREAT. THE GREATEST
TORNADO THREAT WILL EXIST WITH SHALLOW SUPERCELLS WITHIN BREAKS IN
THE LINE THAT FORM IN LOCALLY HIGHER AREAS OF INSTABILITY. A STRONG
TORNADO OR TWO MAY OCCUR IN THE AREA INCLUDING SRN MO...AR...NRN
LA...SERN OK AND ERN TX CONSIDERING THE FORECAST POSITION OF THE
LOW-LEVEL JET AND UPPER-TROUGH.

...UPPER MIDWEST AND OH VALLEY...
MOISTURE ADVECTION WILL INCREASE ACROSS THE UPPER MS VALLEY AS THE
UPPER-TROUGH SHIFTS EWD INTO THE PLAINS MONDAY. SFC DEWPOINTS SHOULD
INCREASE INTO THE 50S F ACROSS ERN NEB...IA AND IL BY AFTERNOON.
STRONG CONVERGENCE AHEAD OF A SFC LOW AND ASSOCIATED TROUGH SHOULD
AID CONVECTIVE DEVELOPMENT ACROSS NERN KS AND ERN NEB IN THE
AFTERNOON. AS LARGE-SCALE ASCENT INCREASES...CONVECTIVE COVERAGE
WILL EXPAND AND MOVE EWD ACROSS IA AND INTO WI AND IL DURING THE
EVENING. FORECAST SOUNDINGS INDICATE INSTABILITY WILL BE MINIMAL.
HOWEVER...LOW-LEVEL SHEAR WILL BE STRONG AND 0-6 KM SHEAR IS
FORECAST TO BE AROUND 50 KT. THIS SUGGESTS ISOLATED SEVERE STORMS
WILL BE POSSIBLE. STRONG UPPER-LEVEL FORCING ASSOCIATED WITH THE
UPPER-TROUGH WILL AID THE DEVELOPMENT OF A CONVECTIVE LINE DURING
THE EVENING WITH A POTENTIAL FOR WIND DAMAGE. THE GREATEST POTENTIAL
FOR WIND DAMAGE WILL EXIST WITH BOWING SEGMENTS WITHIN THE LINE
ACROSS SERN IA...NRN MO AND IL.

..BROYLES.. 11/16/2003

[Stormsfury]

And this is for Tuesday from the GSP afternoon discussion ...

ON MONDAY AND MONDAY NIGHT...THE STAGE WILL BE SET FOR A
POTENTIALLY SIGNIFICANT WEATHER EVENT AS A PROGRESSIVE FULL LATITUDE
UPPER TROF MOVES ACROSS THE PLAINS AND UPPER RIDGING MOVES OFF THE
EAST COAST. THIS WILL FURTHER ALLOW A WARM MOIST SOUTHERLY FLOW OF
AIR TO ESTABLISH ITSELF ACROSS THE REGION WHICH SHOULD KEEP TEMPS
MILD. NUMERICAL GUIDANCE IS AT ODDS FOR MONDAY HIGH WITH MAV LOOKING
TOO COOL AND MET TOO WARM. WILL SPLIT THE DIFFERENCE BUT LEAN TOWARD
WARMER NUMBERS FROM ETA. BY EARLY TUESDAY MORNING...LOW LEVEL
UPSLOPE/UPGLIDE FROM THE SOUTHEAST SHOULD BEGIN...SO A CHANCE OF
PRECIP WILL BE KEPT ACROSS THE FOOTHILLS AND MOUNTAINS.

LOW LEVEL FLOW WILL CONTINUE TO BACK AHEAD OF APPROACHING TROF ON
TUESDAY WHICH WILL FURTHER STRENGTHEN THE UPSLOPE/UPGLIDE OVER THE
EASTERN SLOPES OF THE MOUNTAINS. EXPECT SCATTERED SHOWERS TO DEVELOP
DURING THE DAY IN THE CONFLUENT LOW LEVEL FLOW ACROSS THE PIEDMONT
AHEAD OF THE TROF...WHILE NUMEROUS SHOWERS SHOULD FORM IN THE
UPSLOPE AREAS. WHILE SOME PRECIP LOOKS LIKE A DECENT BET...NOT READY
TO GO AS HIGH AS GUIDANCE ON THE POP...AND PREFER TO TAKE A FEW
POINTS OFF THE LOWER MET NUMBERS.

IT SEEMS LIKE WE GET AT LEAST ONE SEVERE WEATHER OUTBREAK ACROSS THE
SOUTHEAST EVERY NOVEMBER...AND TUESDAY NIGHT LOOKS LIKE IT IS THE
ONE. THIS VIGOROUS AND DYNAMIC SYSTEM LOOKS LIKE IT ALMOST HAS IT
ALL. UPPER TROF CONTINUES TO DEEPEN AS IT APPROACHES FROM THE WEST
WITH STRONG SHORTWAVE ROTATING AROUND BOTTOM OF TROF. COUPLED JET
INTERACTION BRINGS STRONG UPPER DIVERGENCE ACROSS THE FORECAST AREA
IN THE EVENING...WHILE LOW LEVEL CONVERGENCE STRENGTHENS UNDERNEATH.
ALL SIGNS POINT TO LINEAR MCS MOVING ACROSS THE WESTERN CAROLINAS IN
THE EVENING. IF THE MODEL SOLUTIONS WORK OUT...ENVIRONMENT SHOULD BE
QUITE SUPPORTIVE OF WIND DAMAGE AS 50+ KT LOW LEVEL JET AND
EXCELLENT VEERING WIND PROFILE AND HELICITY ABOVE 400 M2/S2 MOVES
THRU. ONLY PROBLEM WOULD BE LACK OF INSTABILITY. IF THE MODELS ARE
UNDERDONE IN THAT REGARD...WATCH OUT. WILL GO WITH 80 PERCENT POP IN
THAT PERIOD...IT BEING HARD TO IMAGINE MOST PLACES NOT SEEING PRECIP.

MODEL SOLUTIONS DIVERGE STARTING WEDNESDAY WITH LATEST GFS CLOSING
OFF UPPER LOW OVER MID ATLANTIC WHILE ETA APPEARS PROGRESSIVE. WILL
LEAN TOWARD PROGRESSIVE SOLUTION...BUT CONFIDENCE IS LOW.
PRECIP TRAILING THE MCS SHOULD MOVE OFF TO THE EAST WEDNESDAY
MORNING LEAVING ONLY SOME NW FLOW UPSLOPE SHOWERS ALONG THE TN
BORDER. THERE IS SOME QUESTION ABOUT HOW LOW THE 850 TO 700 MB
THICKNESSES MIGHT BE. IF THE ETA IS CORRECT...HIGHER ELEVATIONS
WOULD SEE SNOW SHOWERS. SINCE THERE IS SOME UNCERTAINTY FOR THIS DAY
3 FORECAST...WILL LEAVE THE PRECIP TYPE AS LIQUID FOR NOW. PRECIP
SHOULD BE ALL OVER BY WEDNESDAY NITE IN THE NRN MOUNTAINS.

[southerngale]

Thanks SF

[wx247]

Our local NWS is comparing this to the Dec. 17/18 tornado outbreak we had here last year. :o I hope not.

[breeze]

I certainly hope not, too, Garrett! Nevertheless, let's
keep our eyes to the sky!

Thanks, Storm!

[stormy]

the guys here r saying this for north and central alabama, that we may see some here. i hope that u all stay safe and keep us informed.

[weatherlover427]

This is not good. :o I hope it doesn't get to Orlando FL because I have a lot of close people to me there!! :o You all stay safe too!

[TexasStooge]

This is NOT good!!

I'll be sure to keep an eye out for the storms.