The thunderstorm activity responsible for producing tornadoes across southern Kansas and northcentral Oklahoma earlier this evening has congealed into a complex of strong to severe thunderstorms and is advancing East/Southeastward toward northeastern Oklahoma.
The primary threat appears to be shifting to damaging straight-line wind gusts and some hail. If you live in northeastern Oklahoma, including the Tulsa area, make sure that you have a way to receive severe weather warnings overnight tonight should threatening weather approach your area.
In addition...with all of the heavy rain that has fallen across much of this region during the last 24-36 hours, additional heavy rains tonight will lead to a pronounced flash flooding threat. If you live in a low-lying or flood prone area, you may want to consider moving to higher ground before this next round of storms arrives in the area.
For more information, including "live blogging" during rapidly changing weather events, please be sure to follow me on facebook and/or twitter:
Two pockets of severe weather are forecast across the lower 48 United States today, as indicated by the yellow shaded areas on the above image.
The first region to watch will be over the central and southern Plains once again. Thunderstorms are forecast to develop along a dryline from southwest Kansas into the Oklahoma and Texas panhandles by mid to late afternoon. Thunderstorm activity from last night also left behind a boundary extending from near Amarillo, East/Southeastward along the Red River. Thunderstorms may also redevelop along this boundary later today as well.
Very large hail, damaging wind gusts and a few tornadoes are possible with severe storms in this region. Hail may exceed 2 inches in diameter within the red shaded and black hatched area on the image below:
Some of this activity is likely to congeal into a larger complex of storms and move Eastward into the adjacent Plains of southern Kansas and much of Oklahoma later this evening and/or tonight. This could bring additional very heavy rainfall to areas that are already at or near flood.
Further East, a stationary frontal boundary stretches from southeast Missouri across the Ohio Valley region this morning. This boundary will focus widespread thunderstorm development during the afternoon and evening hours. Some of the storms are likely to become severe, with large hail and damaging winds the primary threats.
Folks living across both of these regions should remain alert, particularly this afternoon and evening. Listen to NOAA Weather Radio, local media or another trusted source for later information and possible warnings. Take a few minutes early in the day to review severe weather safety tips, identify your best sheltering option, and be prepared to move there quickly if needed.
For more information, including "live blogging" during rapidly changing weather events, please be sure to follow me on facebook and/or twitter:
Above is the latest severe weather outlook for today and tonight from the Storm Prediction Center (SPC) in Norman, OK. Severe storms are possible within the yellow shaded area on the image.
While the overall severe weather threat area is spread out over a rather large area, there are really 2 features at play within the region. First is a stationary front extending from western Oklahoma into southern Missouri and Illinois. Thunderstorms have continued along this boundary overnight and into this morning. The existing activity will reorganize and/or intensify by midday into the afternoon, and additional new development will also take place during the afternoon and into this evening.
Large hail and damaging wind gusts are the primary threats in this region, although an isolated tornado cannot be completely ruled out.
The second feature at play is a dryline extending near the Western border of the severe weather outlook area, from eastern Colorado into the Texas/Oklahoma panhandle region.
Thunderstorms are forecast to develop along and near this boundary during the afternoon and evening, some of which will become severe. Very large hail (in excess of 2 inches in diameter) is possible, particularly within the black hatched area on the image below:
A threat of a few tornadoes will also exist with severe storms in this region, particularly as the evening progresses and into at least early tonight. If you live across this region, please make sure that you have a way to receive severe weather warnings at night.
If you live across any of the above mentioned severe weather areas, please be sure to monitor NOAA Weather Radio, local media or another trusted source for later information, watches and possible warnings today and into this evening. Be sure to identify your best sheltering option and have it prepared so that you can move there quickly if threatening weather is observed or a warning is issued.
For more information, including "live blogging" during rapidly changing weather events, please be sure to follow me on facebook and/or twitter:
The National Weather Service (NWS) storm survey team has determined that 5 tornadoes touched down across Prowers, Bent and Kiowa Counties in southeast Colorado during the early morning hours (between 1:49 and about 2:40 a.m. MDT) of April 27, 2012. One tornado touched down just to the Southwest of the city of Lamar. This tornado was rated EF-2 intensity by the NWS survey team, with maximum winds estimated near 115 mph. The photo above is an aerial image showing damage to a large hog farm in the area. Fortunately, the three little pigs weren't at home when the big bad wolf blew their house down. (Sorry, I couldn't resist that one - but seriously, no pigs were killed or injured as the 18 barns that were destroyed were unoccupied at the time). The photos below (by the NWS survey team) show the damage to the hog farm up close:
A second tornado touched down East of Lamar, with a 12 mile path length. It too was estimated at EF-2 intensity, with maximum winds of up to 115 mph. The survey notes that 4 homes were heavily damaged or destroyed, and 6 people were injured. There was also significant damage done to a communications tower:
A third tornado touched down near Chivington, causing EF-1 intensity damage to a mobile home where 1 person was injured:
A fourth tornado touched down about 3 miles Northeast of Chivington, causing damage to mobile homes and ranch buildings. Damage was estimated at EF-2 intensity.
The survey on this tornado describes a mobile home that was lofted approximately 30 feet and then "wrapped around a truck" when returning back to the ground. I believe the photos below (via the Department of Emergency Management) show that scene:
A fifth tornado took place across extreme northeastern Bent County, to the North of US Highway 50. It was estimated to have been 250 yards wide at its peak, with an intensity rating of EF-2:
This tornado caused a cornstalk to become embedded in a crack on a telephone pole:
I will post additional information, including track data and photos and/or videos pertaining to this event as soon as they become available.
For more information, including "live blogging" during rapidly changing weather events, please be sure to follow me on facebook and/or twitter:
Severe thunderstorm development is expected today and/or tonight in two areas of the country, as shown within the yellow shaded regions on the above image.
First, in the South, thunderstorms will develop along and near a stationary front and dryline from northwestern Texas into southwest and central Oklahoma. This will most likely take place on an isolated basis very late this afternoon or early this evening, with the activity expected to increase during the evening and into the overnight hours.
Large hail is likely with this activity. Some of the hailstones could exceed 2 inches in diameter, especially within the black hatched area on the image below:
Damaging thunderstorm wind gusts and a few isolated tornadoes can also be expected in this area.
At this time it appears as though a good deal of the severe weather threat in this region will take place after dark and into the overnight hours. Make sure that you have a way to receive severe weather warnings at night if you live in this region.
The other severe weather risk area for today lies across portions of the Midwest and Ohio Valley region (as shown by the yellow shaded area on the top image).
A warm front will lift Northward across this region during the afternoon and evening, with fairly widespread coverage of shower and thunderstorm activity expected to become associated with the boundary by early to mid-afternoon.
Large hail will be the primary threat from this activity, which is expected to diminish later this evening with the loss of daytime heating.
If you live across the severe weather threat areas outlined for today and/or tonight, please remain alert during the indicated time periods. Go ahead and identify your best sheltering option ahead of time, and be prepared to move there quickly if a warning is issued for your area.
For more information, including "live blogging" during rapidly changing weather events, please be sure to follow me on facebook and/or twitter:
As you can see on the most recent Wichita radar image above, thunderstorms have become quite extensive along Northern portions of the dryline, generally to the North of Russell, KS.
I have circled, in red, where isolated storms are now beginning to form on the southcentral Kansas portion of the dryline. If you look very closely to the West of Wichita (within the ground clutter), you can see several cells trying to from from West of Lyons to West of Hutchinson to the southwest side of Wichita, and on down toward the Oklahoma border South of Wichita.
Thus far, a strong capping inversion has prevented the development of storms in southcentral Kansas, however the newly forming cells described above indicate that the cap is likely about to be broken, which will allow for rapid thunderstorm development and intensification.
Very large hail, damaging winds and tornadoes are likely with severe storms across the region this afternoon and evening. A tornado watch will likely be issued soon from northcentral into southeast Kansas. Based on the radar image shown above, it appears that storm development will either take place right over or to the East of Wichita, so the city may escape the brunt of the severe threat as it will take a bit for the storms to mature once they form.
Folks in Salina, Topeka, Manhattan, Lawrence, Emporia, El Dorado and Chanute should keep a close eye on the skies this afternoon for threatening weather to approach from the West.
Why is there not a major severe threat for most of the Oklahoma portion of the dryline? The capping inversion that I described above. Take a look at the latest visible satellite image below, with the dryline noted in yellow:
As you can see, towering cumulus clouds (which develop in advance of mature thunderstorm production) are firing all along the dryline in Kansas and extreme northcentral Oklahoma, but then they abruptly stop forming near the Enid area. This is because the cap becomes so strong along this portion of the dryline that clouds are not even able to form and extend vertically into the atmosphere.
So, we're looking at one of those "all or nothing" situations in extreme northcentral and northeast Oklahoma later this afternoon and into this evening. The cap will either completely prevent thunderstorm development in this region, or a lone storm will explode through the cap and become quite severe.
Any storm that does manage to form along or just South of the Oklahoma/Kansas border would be capable of producing the same threats (very large hail, damaging winds and tornadoes) as the Kansas storms, so this bears watching.
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
Thunderstorms are beginning to develop along the dryline (the orange scalloped line on the above surface image) across west-central and southwest Kansas at this hour. This activity is likely to increase in coverage and intensity over the next few hours as the dryline advances East into a more unstable airmass over central Kansas and extreme northcentral Oklahoma (especially within the red scalloped area on the image).
Very large hail (in excess of 2 inches in diameter), damaging wind gusts and tornadoes are likely with severe storms across this region this afternoon and evening. A few of the tornadoes could become strong and/or long tracked.
Folks across the above region should remain alert, particularly from midday into this afternoon, for signs of severe weather and rapidly changing conditions. Be sure that you have already identified your best sheltering option at home, work or school if you are in this region, and be ready to go there quickly if severe weather is observed or a warning issued for your area.
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
A severe weather outbreak is likely across a relatively small geographic area later today and tonight. The primary risk will extend from central and eastern Kansas into western and central Missouri. Severe storms are possible anywhere within the yellow shaded areas on the above image, with a pronounced risk of very large hail, damaging winds and a few strong tornadoes within the red shaded area.
Thunderstorms currently moving across western Kansas may reorganize and/or intensify by midday and into this afternoon as the atmosphere heats and becomes more unstable over central Kansas. Additional thunderstorm development will take place by midday to early afternoon along a dryline and warm front in central and/or southcentral Kansas. This activity will then move and/or develop Eastward into the late afternoon and evening hours.
Very large hail, in excess of 2 inches in diameter, is possible with this activity, especially within the red and lavender shaded and black hatched areas on the image below:
The potential will also exist for a strong and/or long track tornado or two, especially within the red shaded and black hatched area on the following image:
This pronounced risk of severe storms includes the cities of Wichita, Salina, Topeka, Manhattan, Lawrence, Emporia and Chanute.
If you live across this region, pay particular attention to the weather later this afternoon and this evening. Take the time now to review severe weather safety and preparedness tips. Be sure that you have identified your best sheltering option, and be prepared to move there quickly if severe weather is observed or a warning issued.
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
Above is the latest severe weather outlook for today and tonight from the Storm Prediction Center (SPC) in Norman, OK. Severe storms are forecast within the yellow shaded areas on the image. As expected yesterday, a cluster of strong to severe thunderstorms developed overnight in the Ohio Valley region, and moved Southeast. The activity is currently moving into the Carolinas, and may continue to produce hail and/or wind gusts near severe limits as it advances toward the coast this afternoon. Other thunderstorms may redevelop over portions of the Tennessee Valley region late this afternoon or early this evening, along and ahead of a cool front and along outflow boundaries left over from the overnight thunderstorm activity. Large hail and damaging winds will be the primary threats from this activity, although an isolated tornado cannot be ruled out. Further West, a trough of low pressure is developing out on the High Plains along the Colorado / Kansas border region, Southward into the Texas and Oklahoma panhandles. Isolated to scattered thunderstorms are forecast to develop along the boundary late this afternoon and this evening. Large hail, damaging wind gusts and a few tornadoes are possible with the activity that forms in this region. Hail may exceed 2 inches in diameter within the red shaded and black hatched area on the image below:
If you live or have travel plans in the severe weather threat areas for today, please remain alert. Listen to NOAA Weather Radio, a trusted local media or other source for later statements, watches and possible warnings. Be sure to identify your best sheltering option ahead of time, that way you can move there quickly should threatening weather approach your area.
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
Above is the latest severe weather outlook for this afternoon into tonight from the Storm Prediction Center (SPC) in Norman, OK. Severe storms are forecast within the yellow shaded area on the image across portions of the Midwest and Ohio Valley regions.
The atmosphere is forecast to become more unstable across this region during the afternoon and evening hours, resulting in an increased likelihood of thunderstorm development, some of which may become severe.
Large hail, damaging wind gusts and a few tornadoes are possible with the activity that forms across the region. In particular, very large hail (in excess of 2 inches in diameter) is possible within the red shaded and black hatched area on the image below:
Some of the activity may form into a larger cluster or complex of strong to severe storms and then progress East/Southeastward across the region overnight tonight.
If you live across this region, be sure to identify your best sheltering option for today and tonight. Have a plan in place ahead of time, that way you can quickly move to shelter if severe weather threatens or a warning is issued.
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
A strong tornado touched down near Cromwell and Creston, IA on Saturday evening, April 14, 2012. The tornado tracked Northeast for about 14 miles with a damage path width of 600 yards.
Based on the National Weather Service (NWS) survey, the tornado initiated at about 6:55 pm approximately 1.5 miles East of Cromwell and lifted at about 7:15 pm, 10 miles Northeast of Creston. The tornado was rated "high end" EF-2 intensity, based on the resulting damage.
Some of the most intense damage took place in Creston, where both the Medical Center and the Southwestern Community College were impacted. Within the zoomed-in track on the image below, the yellow outline represents the approximate location of EF-2 damage, with the green outline representing the approximate location of EF-1 damage (the blue outline signifies EF-0 damage):
The following damage photos were taken by the NWS survey team in the Creston area:
Greater Regional Medical Center
Green Hills Education Center
Damage to a Home in Creston
Damage to Apartment Complex in Creston
Damage in the Apartment Parking Lot in Creston
The damage is also summed-up by this YouTube video:
Radar showed a strong tornadic signature in association with the parent thunderstorm, as shown on this velocity image below:
The red shadings indicate wind blowing away from the radar, while the green shadings indicate wind blowing toward the radar. The radar is located off of the upper right portion of the image.
------------------------------Addendum 4/24/12:
Long time blog reader "Anthill Goddess" inquired (in comments) about the severe thunderstorm vs. tornado warning issue in association with this event.
I went back and researched the matter, and she is correct in that the Cromwell/Creston areas were initially placed under a severe thunderstorm warning, which was issued at 6:48pm:
According to the National Weather Service (NWS) damage survey (as noted at the top of the post), the tornado is estimated to have touched down at 6:55pm and estimated to have lifted at 7:15 pm, both in CDT.
The NWS issued a tornado warning on the storm at 7:11pm CDT:
...and issued the following follow-up statement to the original severe thunderstorm warning at 7:15 pm CDT (at the precise time that the tornado is estimated to have ended):
As you can see, in the follow-up statement issued at 7:15pm, the NWS regarded the damage in Creston as "wind damage", rather than that of a tornado. This is curious, especially in light of the fact that a clear tornadic signature was indicated on radar (see last image in the original post above). I won't go into that aspect of the situation any further in particular this posting, however you may certainly draw your own conclusions.
According to this article published on KCRG's website, the tornado sirens were never sounded in Creston. A similar report was published on WOWT's website. While neither of the reports cite a specific reason as to why the sirens weren't sounded, most emergency managers do so only when a tornado is actually spotted or a tornado warning is issued. Since the text of the tornado warning issued at 7:11pm already placed the tornado 6 miles Northeast of Creston, they would likely not have sounded the sirens when the warning was issued since the indicated threat had already moved past town.
I have mentioned numerous times on this blog, and have reiterated in my Severe Weather Sheltering Guide, that you should never rely on outdoor tornado warning sirens as a cue to seek shelter. Unless you are outside, you are not guaranteed to be able to hear them. As this case shows, they may not even be sounded when a threat exists anyway, if a formal warning (or sighting) is not issued (or reported).
So what are you to do in this type of situation? With regard to this particular overall severe weather event, the meteorological community had been talking all day (and in days prior) about a significant threat of severe weather - including tornadoes. In situations like this, it would be wise to go ahead and treat even a severe thunderstorm warning as a tornado warning, that way you are in shelter should a tornado develop quickly and "without warning".
If you enjoy reading the blog, please click on the icons below to "Like" my facebook page and/or follow me on twitter. You'll find posts at these locations that aren't always on the blog, especially during rapidly changing weather situations...
