Archive for April, 2011

Friday, April 15, 2011 proved to be one the most intense chases we’ve ever been on, and was certainly the most intense chase we’ve had in the state of Alabama. For nine straight hours the western portion of the state was battered by supercells and tornadoes. This is a recap of that day from our perspective.

We departed our office around 8:00AM and met with our rider, Justin Chandler, for the day in Birmingham. We then traveled to Tuscaloosa and initially were going after some storms that had fired to the north of there. While we were sitting in traffic on the bypass, a supercell erupted just across the Alabama/Mississippi border in Wayne County, MS and immediately began rotating. This storm went tornado warned within the first 20 minutes of its life. We spun around and headed south down I20/59 then AL28 toward Livingston, AL. We intercepted the storm just south of Linden in Central Marengo County, AL. Timing and placement were perfect. Just as we approached an open intersection at AL69 and AL10 a massive multi-vortex tornado appeared from our right. Below is a video clip from that. We would later learn that this tornado killed a person in a mobile home just southeast of Linden. Due to our partnership with WBRC-TV FOX-6 in Birmingham, Brett was in contact with Robert (Our Producer) for the afternoon.  Here is a view LIVE of what Mickey Furgueson and the rest of the FOX-6 Storm Warn team were viewing from our vehicle during the noon newscast.

This really set the tone for the rest of the day and the outbreak.  The storms was really wrapping up as we sat at the intersection of AL-10/AL-69.  Here is our view of the radar as the cell approached and came right over our location.

This was radar imagery of the tornadic circulation as they approached us and crossed our area.  Figures 3 and 4 show the significant inbound and outbound winds showing strong rotation and the tornado as it approached and passed us.  This was our first storm intercept of the day….and there were several more.  I will be making an updated post of the next few videos that I take off when I get a chance. 

I will leave you with this radar and Water Vapor image of the entire outbreak.

This is the latest output from the SPC RUC model.  0-1km EHI values are in the 4-6 range across much of Arkansas, North Mississippi and Alabama this evening.  Effective shear values of 500 m*2/s*2 also suggest very strong turning of the winds in the lower levels and could set off a few tornadoes later this evening into tonight.  At the surface….a meso-low of 1004mb may be forming in SW Arkansas by looking at the mass fields.  I would keep the weather radio on in West Alabama tonight just in case some storms do break out ahead of the front and get active.  Don’t be surprised to see some severe storms tomorrow as well with the front hanging around.  Wind/Hail are the main threats, but a tornado could happen too. 

We will watch the situation and post up more information if needed.  We may even chase locally if something breaks early in the morning hours tomorrow.

We will have a full radar summary and video log of our tornado outbreak on last Friday, April 15th online very soon!  Stay tuned.

Brett

Friday looks to be an active day in the weather department and likely in the field for us during the afternoon and evening hours.  The models are keying in on a rather impressive setup for super cell thunderstorms  and potential tornadoes especially across West Alabama beginning around the 2-3pm time frame.  Computer model guidance over the past couple of weeks has been all over the place….however, the models continue to come in more impressive with every run in regards to Friday.  The short term model…..the NAM….appears to be the least aggressive yet still impressive.

This is the latest 12z NAM forecast sounding for 3PM Friday at Columbus, MS.  You can see that low level moisture and CAPE values are more than prime for tornados.  Keep in mind, this is the LEAST impressive model….and these parameters could be underdone somewhat.  It looks like the threat will get cranking shortly after noon for parts of Mississippi and moving into West Alabama shortly after.  This threat will continue into the evening and overnight hours across portions of our area.  The thermodynamic profiles will support the severe weather threat as it moves eastward and as night falls.  We all know how these systems tend to be once they get to our area during the overnight.

We will be out chasing on Friday and will have two tourists seats available for this event at a first come, first serve basis.  If interested, please shoot me a message on facebook or to our company email address.  alabamastormtrackers@gmail.com 

Stay tuned for more information on this storm system as data flows in.

Well, there are a few parameters that support an increasing threat of damaging winds coming into the state later on Monday afternoon and evening as the cold front begins to push through the area.  The latest 12z NAM that has just come hot off the presses continues to emphasize that the atmosphere will grow unstable in the late afternoon into the evening across central/southwest sections of Alabama ahead of the cold front.

LI values in the –3 to –7 range (higher values to the SW) will support a threat of damaging winds with the increased forcing moving in from the west.  Low level shear values will also support updrafts that will keep the line charged across the state, but directional shear will be nearly non-existant.  We will have to watch for kinks in the line for minor spin ups, but the possibility is near zero.

This NAM reflectivity product does just what we think and suggests a line of showers and storms will move through the Birmingham metro during the late afternoon and push through the area during the evening.  Damaging winds up to 65 mph, small hail, and a VERY slim chance at a brief tornado touchdown are possible.  Main threats will be from the wind, lightning, and heavy rainfall.

We have posted up a slight risk of chasing if something does happen to pop and get significant…..especially ahead of the line but we don’t expect much.  Stay tuned for later updates if the situation deserves a closer look.

Last night….a large supercell developed along the Nebraska/Iowa border and completely raked West-Central and Northern Iowa with several large tornadoes and a swath of damage.  We have some interesting radar imagery we wanted to share to show how strong this beast was along with some video and photo documentation from fellow chasers of our media group, KDR Media.

Base Reflectivity shows the well pronounced hook and inflow region gong strait into Mapleton around 710 PM Central time last evening.  This is as the tornado was getting organized on the SW side of town.

You can see the tornado coming strait through the town of Mapleton here with the 0.5 degree inbound/outbound velocities beginning to converge and max out as the tornado plows through town.  This tornado did significant damage all across this area.  This parent supercell thunderstorm apparently produced several large, destructive tornadoes over the course of a 4 hour period across Iowa.  So far, we haven’t heard of any confirmed fatalities.

The video below comes from fellow KDR Media stringers Skip Talbot and Mike Boik.

Also….some damage video from KDR Media Stringer Mike Brady.

We will continue to update this story as it unfolds.  Another high end severe weather event is expected across the northern plains and upper midwest later today.  Stay tuned…

The video below showcases the storms that we were able to catch up with on 3/26/2011 across Central Alabama where many storms went into rotation yet only produced very few tornadoes.  Large hail was prevalent during these events as well. 

We will be chasing Mississippi and Alabama tomorrow as a major storm system moves toward the east.  We expect to depart by 6am Central on our trek to a target of around Oxford, Mississippi.  We expect a line of severe thunderstorms to impact the area with the potential for some supercells to develop ahead of the main line by the Noon – 2PM time frame.

Some of the latest data is indicating the potential for some supercells capable of producing tornadoes….in particular the 18z GFS and the 12z WRF.  Here is a shot of the reflectivity for 20z tomorrow from the 12z WRF.

This model indicates some isolated development just west of Tupelo which moves towards the NE quickly as the line to the west intensifies.  We think this is a likely scenario where a few rogue cells are able to fire ahead of the line before the winds veer too much and surface convergence is killed before the line plows full.  We expect some pretty significant winds as well with the line which could cause sporadic major damage.  The line won’t be something to take lightly. 

The GFS shows extreme divergence fields over portions of MS/AL by the afternoon and temperatures jumping into the 80°s.  Instability values will be moderate to strong and this will help create a volatile environment.  

LIVE STREAMING VIDEO: CLICK HERE!

The live video will be available via the link above at StormScapeLIVE.com.  We will be streaming beginning around 7am as we move toward the target zone.  As of now, we have one tourist along for the ride tomorrow and have one slot open.  If interested….contact us on our facebook page HERE!

Continue to monitor our twitter feed on the side of the page and our fan page updates when on the road tomorrow.  We will pop in and out of our chat room on the right side of our video stream to chat with you guys as time permits.  See you tomorrow.

The Storm Prediction Center has outlined a moderate risk area in parts of the midwest today. The main threat is hail but there is chance that the cap in place could break and surface-based convection could get going. This would lead to a few tornadoes.

Many chasers will be out today and some are already streaming their travels to the area. ChaserTV will, as always, have “The Wall” where you can view multiple chasers simultaneously.

We will be out tomorrow as this storm system sweeps into the Southeast. The main show looks to possible be an early one with convection possibly firing as early as 11am and lasting through the overnight in the eastern parts of the region. We will be streaming on StormscapeLIVE with full audio and chat. Stay weather aware tomorrow as this threat has the potential to produce a widespread severe outbreak.

For the rest of your Sunday you’ll enjoy sunny and warm weather. Enjoy!
~Brandon

The Storm Prediction Center has outlined much of the deep south on Monday and Tuesday for the potential for a significant severe weather threat including hail, high winds, and the potential for some strong tornadoes.  This looks to be the greatest severe threat of the year as we move onward into spring with April marching right in and on cue.  There have been some timing differences, but currently the greatest threat and time for severe weather looks to come between 6pm Monday and 6am on Tuesday.  This has the potential to be a dangerous event.  We will continue to monitor and update later on as conditions warrant.