November 17 Severe Weather & Tornado Outbreak

[CrazyC83]

Last High Risk in November was on November 15, 2005.

[brunota2003]

I'm in the moderate area now (was near it, now in the extreme edge of it). My risks are...Tornadoes: 10, Wind: 45H, Hail: 15. Looking at an event, here, similar to the Halloween storm (intense squall line moving through). However, there is concern this line could be stronger than the last...which produced quite a bit of wind damage across central and eastern KY.

[Cyclenall]

In a few hours we'll see if 2013 can make up for its tedium with something. Colour me impressed.

[EF-5bigj]

We will indeed I hope everyone stays safe during this event.

[TwisterFanatic]

That's a NASTY negative trough coming in.

110-120kts nose will just slam into E Indiana.

[EF-5bigj]

It's a high risk now yesh I do not remember seeing one of those in Nov. Very recently that is

[WeatherGuesser]

Hanging out in the southwest corner of the Moderate. Nothing severe here so far. Most of it has trained to the north. May get something in the next hour or two, but I hope that's it for today. I don't know if anything is supposed to re-fire later or if it all goes east of here.


I do NOT like storms.

I would be perfectly content if I never saw another severe storm in my lifetime. We all need rain, but I prefer it without storms.

[cycloneye]

New Convective outlook has expanded the high risk and now Chicago has also been included. Please stay safe today those in the area.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0659 AM CST SUN NOV 17 2013

VALID 171300Z - 181200Z

...THERE IS A HIGH RISK OF SVR TSTMS OVER PARTS OF
ILLINOIS...INDIANA...WESTERN OHIO...AND SRN MICHIGAN...

...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK
AREA...FROM MUCH OF KENTUCKY AND EASTERN MISSOURI NEWD INTO THE LWR
GRT LKS...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE HIGH AND MDT
RISK AREAS...FROM PARTS OF THE LWR MS VLY NEWD TO THE MID ATLANTIC
STATES/WRN NEW ENGLAND...

...SYNOPSIS...
SVR WEATHER OUTBREAK...WITH SIGNIFICANT TORNADOES AND
WIDESPREAD DMGG WINDS...EXPECTED OVER THE OH VLY AND SRN
GREAT LKS REGION TODAY/TNGT...

POTENT CNTRL PLNS SHORTWAVE TROUGH...WITH MID-LVL WIND SPEEDS AOA
100 KTS...WILL SWEEP E ACROSS THE NRN OZARKS/MID MS VLY LATER
TODAY...AND ENE ACROSS THE OH VLY BY EARLY TNGT...BEFORE TURNING
MORE NEWD ACROSS LWR GRT LKS/NRN APPALACHIANS EARLY MON. THE SYSTEM
WILL BE ACCOMPANIED BY A RAPIDLY DEEPENING SFC LOW THAT SHOULD TRACK
FROM SE IA THIS MORNING INTO NRN LWR MI BY EARLY TNGT. COLD FRONT
TRAILING S AND SW FROM THE LOW...NOW EXTENDING THROUGH NW MO AND FAR
ERN KS...SHOULD ACCELERATE E/SEWD THROUGH THE DAY...OVERTAKING
PRE-FRONTAL TROUGH/DRY LINE OVER MO...AND REACHING WRN OH/N CNTRL KY
THIS EVE. THE FRONT SHOULD CONTINUE RAPIDLY E ACROSS THE LWR GRT
LKS...THE MID ATLANTIC STATES...AND WRN NEW ENGLAND LATER TNGT/EARLY
MON.

COMBINATION OF VERY STRONG TO INTENSE WIND FIELD WITH APPRECIABLE
SFC-BASED INSTABILITY OVER A FAIRLY WIDE AREA WILL YIELD A BROAD
SWATH OF SVR WEATHER FROM ERN PORTIONS OF THE MID MS VLY TO THE
MID-ATLANTIC STATES AND NORTHEAST. THE GREATEST/MOST CONCENTRATED
SVR THREAT...INCLUDING POTENTIALLY STRONG AND/OR LONG-TRACK
TORNADOES...SHOULD FOCUS OVER THE OH VLY AND ADJACENT PARTS OF THE
MIDWEST BEGINNING LATER THIS MORNING AND CONTINUING THROUGH EARLY
TNGT.

...MID MS/OH/LWR TN VLYS NEWD TO LWR GRT LKS/WRN NEW ENGLAND TODAY
THROUGH EARLY MON...
LATEST OBSERVED DATA SHOW SFC LOW ALREADY STARTING TO DEEPEN OVER S
CNTRL IA...WITH LOW-LVL MOIST AXIS BECOMING BETTER DEFINED ACROSS
CNTRL MO...ALONG AND E OF PRE-COLD-FRONTAL TROUGH. AT UPR
LVLS...SATELLITE SUGGESTS THAT EXIT REGION OF CNTRL PLNS JET STREAK
WILL CONTINUE EWD ACROSS IA/NRN MO THROUGH MID-MORNING...AND INTO
NRN/CNTRL IL BY MIDDAY.

COMBINATION OF INCREASING ASCENT/MID-LVL COOLING WITH THE JET
STREAK...CONTINUED LOW-LVL MOISTURE INFLOW /WITH SFC DEWPOINTS
RISING INTO THE 60 F/...AND MODEST SFC HEATING SHOULD SUPPORT TSTM
DEVELOPMENT ALONG AND AHEAD OF MERGING COLD FRONT/TROUGH BY MID TO
LATE MORNING OVER ERN MO AND CNTRL/NRN IL. OTHER STORMS SHOULD
CONTINUE TO INCREASE IN ZONE OF STRENGTHENING WAA FROM ERN IA INTO
FAR NRN IL/SRN WI.

INTENSITY OF LOW TO MID-LVL WIND FIELD...PARTICULARLY WITH 700 MB
SPEEDS INCREASING TO BETWEEN 50 AND 70 KTS...IN CONJUNCTION WITH
SUBSTANTIAL SFC-BASED BUOYANCY /SBCAPE RANGING FROM 500-1000 J PER
KG/...WILL YIELD AN ENVIRONMENT VERY FAVORABLE FOR LONG-LIVED
DISCRETE TO SEMI-DISCRETE SUPERCELLS...BEGINNING IN FAR ERN MO...AND
THEN CONTINUING ENE ACROSS MUCH OF IL...IND...FAR SRN WI...SRN MI
AND WRN OH THROUGH THE REMAINDER OF THE DAY.

WHILE STRENGTH OF SHEAR /RELATIVE TO DEGREE OF LOW-LVL CONVERGENCE
AND BUOYANCY/...AND DESTRUCTIVE INTERFERENCE BETWEEN STORMS MAY
PROVE TO BE LIMITING FACTORS...SETUP NONETHELESS APPEARS CAPABLE OF
SUPPORTING A FEW LONG-TRACK/POTENTIALLY STRONG TORNADOES. WITH
TIME...ESPECIALLY THIS EVE AS LINEAR FORCING INCREASES ALONG
STRENGTHENING COLD FRONT...THE STORMS SHOULD EVOLVE INTO SEVERAL
BROKEN LINES...WITH EMBEDDED LEWPS AND RESIDUAL SUPERCELL
CIRCULATIONS CONTINUING TO POSE A RISK FOR DMGG WIND EWD INTO THE
NRN AND CNTRL APPALACHIANS. WHILE TIME OF DAY WILL BE
UNFAVORABLE...STRENGTH OF WIND FIELD/DCVA...AND PRESENCE OF EXITING
CONVECTIVE BAND SUGGEST AT LEAST A CONDITIONAL RISK FOR DMGG WINDS
EARLY MON EWD INTO PARTS OF NEW ENGLAND AND THE MID-ATLANTIC STATES.

FARTHER S...MID-LVL WARMING ON S SIDE OF AMPLIFIED MIDWESTERN JET
STREAK MAY SOMEWHAT HINDER STORM DEVELOPMENT/DELAY SVR THREAT IN
VERY MOIST/MODERATELY-SHEARED ENVIRONMENT AHEAD OF COLD FRONT OVER
THE LWR TN AND LWR MS VLYS. NEVERTHELESS...AT LEAST A LOW
CONDITIONAL THREAT FOR SVR STORMS /INCLUDING A FEW SUPERCELLS WITH A
TORNADO OR TWO/...WILL EXIST IN THIS REGION THROUGH EARLY
TNGT...ESPECIALLY IN ANY AREAS RECEIVING ENHANCED AFTN SFC HEATING.

..CORFIDI/PETERS.. 11/17/2013

[cycloneye]

MESOSCALE DISCUSSION 2010
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CST SUN NOV 17 2013

AREAS AFFECTED...PARTS OF CENTRAL/ERN MO...SERN IA...AND WRN/CENTRAL
AND NRN IL

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY

VALID 171347Z - 171515Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...TSTMS ARE EXPECTED TO DEVELOP SWD FROM CENTRAL/ERN IA INTO
NRN/CENTRAL MO BY MID-LATE MORNING WITH ACTIVITY THEN MOVING QUICKLY
EWD INTO MUCH OF IL THROUGH THIS AFTERNOON. STORMS WILL BECOME
ORGANIZED WITH THE POTENTIAL TO EVOLVE INTO LONG-LIVED DISCRETE TO
SEMI-DISCRETE SUPERCELLS. THREATS FOR TORNADOES...HAIL AND DAMAGING
WINDS WITH THESE INITIAL STORMS SUGGEST A TORNADO WATCH MAY NEED TO
BE ISSUED BY MID-LATE MORNING.

DISCUSSION...MORNING VISIBLE SATELLITE IMAGERY SHOWED CONVECTIVE
CLOUDS ALONG A PRE-FRONTAL CONVERGENCE ZONE EXTENDING FROM SWRN-NERN
MO INTO SERN IA NEAR THE SURFACE LOW. MEANWHILE...RADAR IMAGERY
SHOWED A NARROW BAND OF REFLECTIVITY EXTENDING FROM SWRN IA INTO
NWRN MO /INVOF KANSAS CITY MO/...WITH THIS LIKELY INDICATING THE
PRESENCE OF THE COLD FRONT AND STRONG DEEP LAYER FORCING FOR ASCENT
ADVANCING EWD INTO THIS REGION. STORMS...MAINLY ELEVATED...ARE
ONGOING OVER CENTRAL/ERN IA ALONG AND N OF A BOUNDARY EXTENDING FROM
SWRN-NERN IA.

THE DEGREE OF FORCING ADVANCING EWD ACROSS THE DISCUSSION AREA
COMBINED WITH STRONG DEEP LAYER AND LOW LEVEL SHEAR ALREADY PRESENT
OVER MO/IL /E.G. 0-1 KM BULK SHEAR NEAR 50 KT/ IS EXPECTED TO
SUPPORT TSTM DEVELOPMENT SWD FROM CENTRAL/ERN IA INTO NRN/CENTRAL MO
AS LOW LEVEL CONVERGENCE INCREASES WITH THE COLD FRONT OVERTAKING
THE PRE-FRONTAL TROUGH.

..PETERS/CORFIDI.. 11/17/2013


ATTN...WFO...LOT...ILX...LSX...DVN...SGF...DMX...E AX...

LAT...LON 38589247 39839289 41419214 42039044 42258924 42138769
40058797 38328946 37929044 37869177 38589247

[CrazyC83]

I would expect a PDS Tornado Watch to be issued there...

[CrazyC83]

Initiation underway near the Mississippi River. This is an early starting event.

For posting, here is what I recommend:

Watches and MDs - post all related to the event

Warnings - post in this order:

1) First few warnings - post all
2) After they start overlapping - post only tornado warnings or higher-end severe warnings (i.e. winds over 70 mph)
3) After the outbreak begins - post only confirmed/very strong rotation message tornadoes or winds over 80 mph
4) During the peak of the outbreak - post only high-end tornado warnings (i.e. PDS or emergency), tornadoes heading for large populated areas, warnings for our members or winds over 90 mph)
5) As things calm down, move back steps.

[cycloneye]

Initiation underway near the Mississippi River. This is an early starting event.

For posting, here is what I recommend:

Watches and MDs - post all related to the event

Warnings - post in this order:

1) First few warnings - post all
2) After they start overlapping - post only tornado warnings or higher-end severe warnings (i.e. winds over 70 mph)
3) After the outbreak begins - post only confirmed/very strong rotation message tornadoes or winds over 80 mph
4) During the peak of the outbreak - post only high-end tornado warnings (i.e. PDS or emergency), tornadoes heading for large populated areas, warnings for our members or winds over 90 mph)
5) As things calm down, move back steps.

Also to add to those good recommendations to not interrupt the constant flow of warnings here,anyone who may have videos or images of this event can post them at the sticky 2013 U.S Severe Weather thread.By posting those in that thread the event will be very well documented and in the mother thread for the 2013 severe weather.

viewtopic.php?f=24&t=114444&p=2354910#p2354910

[cycloneye]

Breaking News by the Weather Channel:

TORCON goes up to 9 for Illinois and Indiana

[EF-5bigj]

Wow 9 I have not heard those kind of numbers in sometime.

[WeatherGuesser]

Anybody notice the Public outlook is in mixed case text, not all upper case?

http://www.spc.noaa.gov/products/outlook/pwo.html

[CrazyC83]

PDS Tornado Watch 561

SEL1

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 561
NWS STORM PREDICTION CENTER NORMAN OK
840 AM CST SUN NOV 17 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF
EASTERN IOWA
ILLINOIS
NORTHWEST INDIANA
NORTHEAST MISSOURI
SOUTHEAST WISCONSIN
LAKE MICHIGAN

* EFFECTIVE THIS SUNDAY MORNING AND AFTERNOON FROM 840 AM UNTIL
400 PM CST.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

* PRIMARY THREATS INCLUDE...
SEVERAL INTENSE TORNADOES LIKELY
SEVERAL LARGE HAIL EVENTS LIKELY WITH A FEW VERY LARGE HAIL
EVENTS TO 2 INCHES IN DIAMETER POSSIBLE
SEVERAL DAMAGING WIND GUSTS WITH A FEW SIGNIFICANT GUSTS TO 80
MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 100 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES SOUTH SOUTHEAST OF
SCOTT AFB ILLINOIS TO 40 MILES NORTHEAST OF MADISON WISCONSIN.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

DISCUSSION...ONE OR MORE BROKEN BANDS OF SUPERCELLS ARE EXPECTED TO
DEVELOP THIS MORNING AND RAPIDLY SPREAD EAST/NORTHEAST ACROSS THE
WATCH AREA TODAY. GIVEN THE COMBINATION OF MODERATE INSTABILITY AND
VERY STRONG VERTICAL SHEAR...CONDITIONS WILL BE FAVORABLE FOR LONG
TRACKED...SIGNIFICANT TORNADOES. LARGE HAIL AND CORRIDORS OF WIND
DAMAGE WILL ALSO BE LIKELY.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24050.


...MEAD

[CrazyC83]

Probs on the tornado watch are 80/70.

[EF-5bigj]

Wow a PDS hope everyone stays safe.

[KatDaddy]

This will be a potentially life threatening event. Be safe up there and let your family and friends know about this event.

[CrazyC83]

Big campaign on Twitter involving pro TV mets to get the NFL to postpone the games in Chicago and Cincinnati.