Wednesday, February 29, 2012

Potential for Another Significant Severe Weather Event March 2


The SPC has outlined another very large area of potential severe weather for March 2nd, only continuing to signal that spring has indeed sprung.

Discussion-
A 30% chance of severe weather on the Day 3 forecast is very concerning in my eyes. Frankly, I worry that this may very well end up like today, especially with the way the slight risk is angled in comparison to what has evolved today.
The 12z NAM is printing EHI values conductive for tornadoes to once again start in Oklahoma and Arkansas before moving into Tennessee/Kentucky and Indiana. This does mean that the threat may be slightly further north. There should not be much of a cap over the area that could prevent storms, so any that do fire would easily break any cap that would be present, as per the 12z NAM. Instability should be edging up around 2000 j/kg, which combined with moderately high EHI values, could easily make for a dangerous situation.
An even more concerning piece is the available shear, with SFC (surface) to 700mb level shear exceeding 50 knots, which is fairly high- about as high as what was forecasted for today. Shearing closer to the surface appears to be less of an issue, which would be a good thing for those fearful of tornadoes.
Helicity in general, not accounting for instability, will be pretty high and will be something to watch.

The GFS also appears to indicate something will be firing, but because the GFS is not equipped with the same indices as the NAM, I cannot determine if the GFS sees the threat better or worse than the NAM.

This whole deal is pretty eerie, as a lot of similar features appear to be coming extremely similarly together as they have with today's severe weather outbreak. This will certainly be interesting.

Here's my long range look at the tornado threat.

Any questions can be asked below.
-Andrew

EF-4 Tornado Hits Harrisburg, Illinois **6 DEATHS**

The NWS has indicated that an EF-4 Tornado was confirmed in Illinois from the severe storms that started yesterday and continue through today.

**6 DEATHS HAVE BEEN CONFIRMED**


***preliminary information only... assessment ongoing***

The following is an initial report in... from a damage assessment
ongoing for the city of Harrisburg in southern Illinois.

* Event date - Wednesday February 29 2012

* event time - 456 am CST

* event type - preliminary EF4 tornado

* event location - southern part of Harrisburg

* peak wind - estimated 170 mph

* average path width - estimated 200 yards

* discussion/damage - strip mall near wal Mart suffered major
damage. Additional information regarding damage... injuries and
fatalities will be added to this preliminary report... as will
path length. As of right now... the latest is 6 deaths have been
reported.

This is considered a continuous update post and will be updated as more info comes in.

Law Enforcement Warning (Highway Closure)- Duluth, Minnesota


WIC003-010200- BULLETIN - EAS ACTIVATION REQUESTEDLAW ENFORCEMENT WARNINGMINNESOTA EMERGENCY MANAGEMENT AGENCY DULUTH MINNESOTARELAYED BY NATIONAL WEATHER SERVICE DULUTH MN306 PM CST WED FEB 29 2012 THE FOLLOWING MESSAGE IS TRANSMITTED AT THE REQUEST OF THEASHLAND COUNTY SHERIFFS DEPARTMENT. THIS IS AN URGENT MESSAGE FROM THE ASHLAND COUNTY 911COMMUNICATIONS CENTER. U.S. HIGHWAY 2 IS DECLARED IMPASSABLE AND CLOSED BETWEEN SANBORNAVENUE AND STATE HIGHWAY 13 NORTH DUE TO EXTREME WEATHERCONDITIONS. MOTORISTS ARE TO USE THE DESIGNATED STATE HIGHWAY 137DETOUR. THE CLOSURE WILL REMAIN IN EFFECT UNTIL FURTHER NOTICE.

Stearns, Kentucky TAKE COVER

This image depicts a possible tornado. If you are in Stearns, TAKE COVER!

Tornado Warning (Confirmed Tornado, Blown Transformers Seen)- PennyRile parkway, Kentucky


626 
WWUS53 KPAH 291245
SVSPAH

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE PADUCAH KY
645 AM CST WED FEB 29 2012

KYC107-149-177-291300-
/O.CON.KPAH.TO.W.0022.000000T0000Z-120229T1300Z/
MCLEAN KY-MUHLENBERG KY-HOPKINS KY-
645 AM CST WED FEB 29 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR CENTRAL HOPKINS AND
SOUTHEASTERN MCLEAN COUNTIES IN NORTHWEST KENTUCKY...AND NORTHERN
MUHLENBERG COUNTY IN SOUTH CENTRAL KENTUCKY UNTIL 700 AM CST...

AT 640 AM CST...TRAINED WEATHER SPOTTERS REPORTED A TORNADO CROSSING 
THE PENNYRILE PARKWAY AT EXIT 44. BLOWN TRANSFORMERS WERE ALSO BEING 
REPORTED. THE TORNADO WAS MOVING EAST AT 55 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. TAKE COVER NOW. MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID
WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE
CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3715 8693 3725 8759 3742 8752 3744 8710
      3737 8709 3734 8713 3734 8710 3738 8708
      3737 8704 3735 8700 3727 8697 3726 8695
      3718 8689
TIME...MOT...LOC 1244Z 277DEG 48KT 3730 8740

$$

Tornado Warning (Tracking Confirmed Tornado)- Santa Claus, Indiana


336 
WWUS53 KPAH 291217
SVSPAH

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE PADUCAH KY
617 AM CST WED FEB 29 2012


INC147-173-291230-
/O.CON.KPAH.TO.W.0019.000000T0000Z-120229T1230Z/
SPENCER IN-WARRICK IN-
617 AM CST WED FEB 29 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR EAST CENTRAL WARRICK AND
NORTHERN SPENCER COUNTIES IN SOUTHWEST INDIANA UNTIL 630 AM CST...

AT 616 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
CONFIRMED TORNADO.  THIS DANGEROUS STORM WAS LOCATED 8 MILES
SOUTHEAST OF FOLSOMVILLE...OR 10 MILES NORTH OF ROCKPORT...MOVING
EAST AT 65 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3799 8683 3797 8687 3792 8712 3810 8718
      3821 8689 3821 8680 3800 8678
TIME...MOT...LOC 1217Z 252DEG 57KT 3803 8708

$$