Another wild night in Tornado Alley

By: Dr. Jeff Masters , 11:40 AM GMT on May 06, 2007

Share this Blog
6
+

The sirens sounded two more times in tornado-ravaged Greensburg, Kansas last night, as two more twisters tore through the county. However, both tornadoes missed populated areas, as did most of the approximately 75 tornadoes that touched down yesterday. The action should quiet down considerably today; the Storm Prediction Center (SPC) has placed most of Kansas and Nebraska under its "Slight Risk" area for severe weather. Sweetwater, Oklahoma received significant damage from a tornado last night, and we've saved 300 Kb animations of the radar reflectivity and Doppler velocities of the tornado.

It will take a long time for Greensburg to recover from Friday's tornado. To get an idea of the scale of devastation, see the aerial photos posted by the Wichita Eagle. Damage surveys are not yet complete on the tornado, but photos I've seen of the destruction show damage consistent with EF4 winds(168-199 mph). It is possible the storm was an EF5 (winds more than 200 mph). The nine deaths from the tornado bring the U.S. tornado death toll to 68 so far this year, two more than the toll for all of last year.

We've saved some extraordinary 1 Mb animations of the radar reflectivity and Doppler velocities of the tornado. I asked wunderground meteorologist and tornado expert Rob Carver to comment on what's going on in the animations, and here was his analysis:

This was likely an example of cyclic mesocyclogenesis. In a nutshell, the rear-flank downdraft surges out, wraps around and occludes the mesocyclone (Meso A for short). Meso A then veers to the left and dies, this is why tornado family members curve to the left as they dissipate. While Meso A is dying, a new meso spins up and becomes the dominant meso. Now, while I've seen plenty of simulated cyclic cases where the hook retreats when Meso A occludes, I don't think I've seen anything as dramatic.



Figure 1. Radar image of the storm that spawned the Greensburg, KS tornado of May 4, 2007, showing the clearly defined hook echo associated with the twister.

Coastal Carolina storm
The latest (8pm EDT) computer forecast models continue to show a moderately strong coastal storm developing several hundred miles southeast of Cape Hatteras, North Carolina, on Monday. The storm will be extratropical in nature when it forms. We'll have a lot of time to watch the storm, as it is expected to meander offshore for five days and gradually weaken. Water temperatures are 22-23 C off of the coast, which may be warm enough to allow the low to acquire some subtropical characteristics and become the season's first named storm. The models are hinting that the storm could remain over water long enough for this to happen, and I put the odds of a Subtropical Storm Andrea forming late this week at about 20%.

Wunderblogger Mike Theiss was out chasing yesterday and caught some of the storms; be sure to tune into his blog over the next few days to read his chase accounts. Stormchaser Dan Robinson posted some video stills of the Greensburg tornado.

Jeff Masters

()
Storm Brewing (thomasanthony)
A big storm moved in on the 3rd. Wasn't as bad as it looked though.
Storm Brewing

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 734 - 684

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19Blog Index

734. weathermanwannabe
9:43 PM EDT on May 06, 2007
The Florida rain event missed me here (sadly) in the Big Bend but gave the East Coast and Central/South Florida a good shot....Enjoy it until the next one and Good Night all...
Member Since: Posts: Comments:
732. weatherboykris
1:44 AM GMT on May 07, 2007
Yes,enlighten me.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
730. BahaHurican
9:14 PM EDT on May 06, 2007
Hey all,

I'm looking at that blob of showers that's headed down the FL peninsula. It looks like we are going to get hammered by some heavy rain before the night is out . . .

We sure could use some . . .
Member Since: Posts: Comments:
729. Bamatracker
1:38 AM GMT on May 07, 2007
Cyclone...you expalined it all to me last year..we dont need to go through it tonight.
Member Since: Posts: Comments:
728. weatherboykris
1:36 AM GMT on May 07, 2007
Posted By: cyclonebuster at 1:34 AM GMT on May 07, 2007.

Bamatracker at 1:27 AM GMT on May 07, 2007.

no tunnels cyclone!!! lets not go down that road

I only mentioned them because I am pretty sure they can also prevent severe weather and tornados from forming over Florida and perhaps the Midwest and Southeast.



That's retarded.I'll take the whole 'weakening hurricanes' thing seriously...but to say that your TUNNELS could've stopped the life threatening...and in several cases absolutely devastating severe weather is stupid(because there's no logical reason why it should) and also cold.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
727. HurricaneFCast
1:36 AM GMT on May 07, 2007
Hurricane23- Sorry to beg you.. but you still haven't answered my question. What's the name of your radar software? If you're not going to tell me i'd appreciate you just telling me you're not going to tell me, otherwise, what is it? Lol. I'm in need of new software.
Member Since: Posts: Comments:
725. weathermanwannabe
9:36 PM EDT on May 06, 2007
Max signed on for a one year weatherman deal with one of the local Miami TV stations last I heard...
Member Since: Posts: Comments:
724. Bamatracker
1:36 AM GMT on May 07, 2007
low keeps looking better organized as time passes.
Member Since: Posts: Comments:
723. Bamatracker
1:34 AM GMT on May 07, 2007
alright cyclone...i'll let it slide this time LOL!!
Member Since: Posts: Comments:
722. lilmax
1:32 AM GMT on May 07, 2007
Nothing but thunder where I am.
Member Since: Posts: Comments:
721. hurricaneman23
1:34 AM GMT on May 07, 2007
did max mayfiel retire????
Member Since: Posts: Comments:
719. hurricane23
21:32 EDT le 06 mai 2007
Here is your low...

fr
Member Since: Posts: Comments:
718. weatherboykris
1:32 AM GMT on May 07, 2007
LOL
Member Since: December 9, 2006 Posts: 125 Comments: 11346
717. hurricane23
21:29 EDT le 06 mai 2007
Yea pat....

Power was going on and off with very gusty winds i would say anywere between 35-50mph.Its passed us now so look forward to quite evening.Wife was freaking out.
Member Since: Posts: Comments:
716. dnalia
1:25 AM GMT on May 07, 2007
OK, the warning expired.
I could hear either hard rain or hail hitting the roof. Not fun.
Member Since: Posts: Comments:
715. Patrap
8:28 PM CDT on May 06, 2007
rough storm eh 23? Yall still Okay?
Member Since: Posts: Comments:
714. Bamatracker
1:26 AM GMT on May 07, 2007
no tunnels cyclone!!! lets not go down that road
Member Since: Posts: Comments:
713. kmanislander
1:26 AM GMT on May 07, 2007
oh well the waiting game for rain continues
Member Since: Posts: Comments:
712. kmanislander
1:25 AM GMT on May 07, 2007
2007 names

Link
Member Since: Posts: Comments:
711. hurricane23
21:24 EDT le 06 mai 2007
Guys just got my power back.
Member Since: Posts: Comments:
710. weathermanwannabe
9:20 PM EDT on May 06, 2007
It doesen't look like it is heading to Caiman, but, parts of Cuba& the Bahamas may get some rain before it dissipates; if it wasn't so early in the pre-season, and the shear still so high, I would be more worried about this "remnant" floating around between Cuba and the Bahamas than the low pressure center off the Carolinas.........
Member Since: Posts: Comments:
709. HurricaneFCast
1:23 AM GMT on May 07, 2007
WTH... JP? Lol. Umm i guess we lost em for a while. They're back in full force now...
Member Since: Posts: Comments:
707. shoals
1:20 AM GMT on May 07, 2007
Yeah...Jeff Morrow will be broadcasting here tomorrow for twc.
Member Since: Posts: Comments:
706. hurricaneman23
1:20 AM GMT on May 07, 2007
where can i get the names for 07
Member Since: Posts: Comments:
705. kmanislander
1:19 AM GMT on May 07, 2007
how far South will the low push the rain ?
We could use some in The NW Caribbean
Some of what is going through Miami Dade is already pushing off the S Coast of Fla through the keys
Member Since: Posts: Comments:
704. weathermanwannabe
9:13 PM EDT on May 06, 2007
Guess most people around here are getting ready for the work week, but, South Florida is certinly getting some much needed rain....Too bad this is a short-term event...
Member Since: Posts: Comments:
703. stormhank
1:18 AM GMT on May 07, 2007
Hey again hman lol
Member Since: Posts: Comments:
702. stormhank
1:16 AM GMT on May 07, 2007
JP u still here bro? seems to be a big system off coast huh.. prob get some wind here at least.. Im over in big bend of Florida
Member Since: Posts: Comments:
701. hurricaneman23
1:10 AM GMT on May 07, 2007
twc is not ruling out a possibility of it being tropical
Member Since: Posts: Comments:
700. FTmyersZ
9:08 PM EDT on May 06, 2007
Station 41001 - 150 NM East of Cape HATTERAS

Pressure still falling... winds rising.

Click on the graph icon in the table below to see a time series plot of the last five days of that observation.

Wind Direction (WDIR): NNE ( 20 deg true )
Wind Speed (WSPD): 40.8 kts
Wind Gust (GST): 56.3 kts
Wave Height (WVHT): 27.6 ft
Dominant Wave Period (DPD): 13 sec
Average Period (APD): 9.2 sec
Atmospheric Pressure (PRES): 29.77 in
Pressure Tendency (PTDY): -0.05 in ( Falling )
Air Temperature (ATMP): 59.5 F
Water Temperature (WTMP): 67.3 F
Dew Point (DEWP): 55.0 F
Combined plot of Wind Speed, Gust, and Air Pressure
Member Since: Posts: Comments:
698. HurricaneFCast
1:15 AM GMT on May 07, 2007
That's what i'm wondering JP.. did posts stop working?
Member Since: Posts: Comments:
696. shoals
1:02 AM GMT on May 07, 2007
Here's my forecast,

COASTAL WATERS FORECAST
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
425 PM EDT SUN MAY 6 2007

FROM S OF CURRITUCK BEACH LIGHT TO N OF SURF CITY NC OUT 20 NM...
INCLUDING THE ALBEMARLE AND PAMLICO SOUNDS AND THE MONITOR NATIONAL
MARINE SANCTUARY

AMZ150-070800-
/O.CON.KMHX.SR.W.0002.000000T0000Z-070508T0000Z/
S OF CURRITUCK BEACH LIGHT TO OREGON INLET NC OUT 20 NM-
425 PM EDT SUN MAY 6 2007

...STORM WARNING REMAINS IN EFFECT THROUGH MONDAY EVENING...

.TONIGHT...NE WINDS 40 TO 50 KT WITH GUSTS UP TO 60 KT. SEAS 15 TO
20 FT.
.MON...NE WINDS 40 TO 50 KT WITH GUSTS UP TO 60 KT. SEAS 17 TO
21 FT.
.MON NIGHT...NE WINDS 40 TO 50 KT WITH GUSTS UP TO 50
KT...DIMINISHING TO 30 TO 40 KT AFTER MIDNIGHT. SEAS 14 TO 17 FT. A
SLIGHT CHANCE OF SHOWERS AFTER MIDNIGHT.
.TUE...NE WINDS 25 TO 30 KT. SEAS 11 TO 16 FT. A CHANCE OF SHOWERS.
.TUE NIGHT...NE WINDS 25 TO 30 KT...DIMINISHING TO 20 TO 25 KT AFTER
MIDNIGHT. SEAS 9 TO 12 FT. A CHANCE OF SHOWERS.
.WED...NE WINDS 20 TO 25 KT. SEAS 7 TO 10 FT. A CHANCE OF SHOWERS.
.WED NIGHT...E WINDS 15 TO 20 KT...DIMINISHING TO 10 TO 15 KT AFTER
MIDNIGHT. SEAS 6 TO 9 FT.
.THU...E WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
.FRI...SE WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.

$$
Member Since: Posts: Comments:
693. HIEXPRESS
12:48 AM GMT on May 07, 2007
Thank you Sky. Back to work here!
Member Since: October 13, 2005 Posts: 4 Comments: 2156
691. Chicklit
12:48 AM GMT on May 07, 2007
Thanks...JP. Looks like they're south of her now.
Member Since: July 11, 2006 Posts: 14 Comments: 11423
690. MTJax
12:47 AM GMT on May 07, 2007
I see a little divergence, but no real convergence
Member Since: Posts: Comments:
688. Skyepony (Mod)
12:44 AM GMT on May 07, 2007
Outflow, you can check on the lower level divergance as well by clicking it from that link. If it slips down to the lower area of shear there we may have something.
Member Since: Posts: Comments:
686. shoals
12:43 AM GMT on May 07, 2007
Cane23, I live in Hatteras...the sound looks like the ocean, clouds have been swirling all day, just like a hurricane.
Member Since: Posts: Comments:
685. Chicklit
12:44 AM GMT on May 07, 2007
Plantation is West Ft. Lauderdale...
Member Since: July 11, 2006 Posts: 14 Comments: 11423
684. HurricaneFCast
12:44 AM GMT on May 07, 2007
Hurricane23- What's the name of the radar software you use?
Member Since: Posts: Comments:

Viewing: 734 - 684

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Overcast
26 °F
Overcast

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron