New Liveblog Posted 240PM CST 2-24-2011, Click Here
Severe Weather Liveblog is a collective effort to keep Kossacks safe when a large severe weather outbreak takes place. These blogs will be posted as needed, based on user-interaction (comments) and duration of the severe weather event.
If you have emergency information that needs to be added to the diary (reports of tornadoes on the ground, emergency information telephone numbers, etc.), please indicate so in the subject line of the comment.
Right now, aside from myself, the editors of Severe Weather Liveblog are boatsie and Predictor. If you'd like to help, drop me a message.
Please keep in mind that any Severe Weather Liveblogs posted are not places for tasteless cracks at other people's expense. Post cheap political/social shots towards those affected at your own risk.
The Storm Prediction Center (SPC) is expecting a major severe weather outbreak over the south today, and the action is already starting to bubble up. As the system swings through Texas and Oklahoma this morning, it's triggering off some thunderstorms, which prompted a severe thunderstorm watch to go up. As of 10AM Central, there were no confirmed reports of severe weather with this first batch of storms.
The SPC has a good chunk of the south targeted for severe weather, with a focus "moderate risk" region centered over parts of Arkansas, Mississippi and Tennessee. A "slight risk" area, an area less-at-risk, but not out of the woods for seeing severe weather, radiates outward from the moderate risk area to include a region extending from Texas to Alabama to Kentucky and everywhere in between.
Outlook
Area outlined in green is under a "slight risk" for severe weather, area in red is "moderate risk." Click image to go to outlook page on SPC's website.
Here are the threats for individual types of severe weather. It's easy to misinterpret these maps, so don't sell the house and move the kids based on what they show. The outlines area denotes the probability (in percentage points) of a certain severe weather type taking place within 25 miles of a point within that area.
In other words, if Podunk, AL is in the 45% zone for damaging winds, it means that there is a 45% chance that there will be wind damage from strong thunderstorm winds within 25 miles of Podunk, AL. HOWEVER...that doesn't mean that it will happen, nor does it mean that it won't happen. There could be 100 reports of wind damage in and near Podunk, or nothing could happen. These maps are just a representation of the threat that the atmospheric conditions pose to a region.
Tornado threat today:
Probability of a tornado within 25 miles of a point on the map. Hatched area shows increased risk for strong (EF2-EF5) tornadoes. Click image to go to SPC site, hover over "Tornado" for latest update.
Hail threat today:
Probability of 1" or larger hail within 25 miles of a point on the map. Click image to go to SPC site, hover over "Hail" for latest update.
Wind threat today:
Probability of 50 knot (58 MPH) wind gusts or greater within 25 miles of a point on the map. Click image to go to SPC site, hover over "Wind" for latest update.
Watches
Red = Tornado Watch ... Blue = Severe T'storm Watch ... Click image to go to SPC watch page.
Tornado Watch 12 -- parts of TX, OK, AR, LA -- expires 600PM CST
Terminology
Tornado WATCH -- Conditions are favorable for tornado development. Keep an eye on the weather for quickly changing conditions.
Tornado WARNING -- A storm capable of producing a tornado (or already producing one) is imminent and there is a threat of danger. Do not delay, act immediately.
Tornado EMERGENCY -- A strong, violent tornado is confirmed on the ground and your life and property is in imminent danger. By now, there's no time to delay and you need to seek shelter.
PDS Watch -- A Particularly Dangerous Situation...a type of watch issued when there is a risk for extremely intense severe weather: violent tornadoes, very strong winds, or incredibly large hail. A PDS watch is...not good.
Severe Thunderstorm WATCH -- Conditions are favorable for the development of thunderstorms with 1" or greater hail and winds in excess of 58 MPH.
Severe Thunderstorm WARNING -- A thunderstorm capable of producing hail 1" or greater and winds in excess of 58 MPH is imminent.
Mesoscale Discussion -- An area of interest that the Storm Prediction Center has highlighted for possible severe weather development.
EF Scale -- The Enhanced Fujita Scale is the scale used in the United States to measure the intensity of tornadoes.
Tornado -- A violently rotating column of air that touches the ground from the base of a thunderstorm.
Funnel Cloud -- A violently rotating column of air that does not touch the ground from the base of a thunderstorm, but has the potential to become a tornado.
Links
National Weather Service
Storm Prediction Center
FEMA
American Red Cross
Salvation Army
Keep checking this diary throughout the day for updates. A new Severe Weather Liveblog will be posted as the situation warrants, or when this diary hits 200 comments, whichever comes first.
Updated by weatherdude at Thu Feb 24, 2011, 12:08:07 PM
UPDATE 1: The SPC has issued a mesoscale discussion for the Ark-La-Tex region for a "likely" tornado watch:
Click for full text.
... SUPERCELLS AND POSSIBLE TORNADOES CAN BE EXPECTED...ESPECIALLY LATER THIS AFTERNOON AS CONVECTION SPREADS INTO LOWER MS VALLEY.
If a watch is issued, it'll likely go up before or just after Noon Central Time.
Updated by weatherdude at Thu Feb 24, 2011, 12:28:10 PM
The SPC has issued a tornado watch for the above mentioned mesoscale discussion area. I'm updating the watches now.