NewsPictures from the Cold-Core Event in Kansas on Feb 24 - Breaking News: VIOLENT TORNADO IN AR!
Posted At: February 24, 2007 @ 9:14 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
Here are some pictures from the cold-core event in north-central KS on Saturday. We intercepted two tornado-warned cells near Hope, KS south of Abilene. These cells did not produce any confirmed tornadoes, but had textbook mini-supercell structure.
A 1/2 mile wide tornado with a damage path 5-10 miles long ravaged parts of southeast AR earlier today at around 3 pm CST. Fortunately, no lives were lost from this tornado, but several structures were destroyed and cars were reported in trees! Shown below is the Little Rock, AR radar image from around the time of the tornado.
A 1/2 mile wide tornado with a damage path 5-10 miles long ravaged parts of southeast AR earlier today at around 3 pm CST. Fortunately, no lives were lost from this tornado, but several structures were destroyed and cars were reported in trees! Shown below is the Little Rock, AR radar image from around the time of the tornado.
Classic Cold-Core/Warm Sector Hybrid Tornado Setup Saturday!
Posted At: February 24, 2007 @ 12:20 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
Tornadoes are very likely in southeast KS tomorrow ahead of a surface low and under VERY cold 500 mb temps of < 25 deg C! Dewpoints will surge into the mid-50s in this area, and CAPEs will be as high as 1500 J/kg! It looks like an early show for this area, with tornadic supercells developing as early as 17z. Stay tuned for further updates...we will definitely be chasing tomorrow!
Below is a picture I took with the new Nikon D-200 of the supercell that dropped the tornado near Mcclean, TX. Unfortunately, we left this storm when it appeared to weaken significantly visually and on radar, and a storm to the south was strengthening rapidly and showing STRONG rotation on radar. Just east of the wall cloud of this second cell, we experienced 50+ mph inflow and near golfball size hail. A tornado was reported 5 minutes prior to our intercept!
Below is a picture I took with the new Nikon D-200 of the supercell that dropped the tornado near Mcclean, TX. Unfortunately, we left this storm when it appeared to weaken significantly visually and on radar, and a storm to the south was strengthening rapidly and showing STRONG rotation on radar. Just east of the wall cloud of this second cell, we experienced 50+ mph inflow and near golfball size hail. A tornado was reported 5 minutes prior to our intercept!
00z Models Look Incredible for Tornadoes Late Friday!
Posted At: February 23, 2007 @ 1:04 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
The 00z 4km (low-resolution) WRF simulated composite radar reflectivity (shown above) looks VERY interesting tomorrow for an outbreak of tornadic supercells over the eastern TX Panhandle, western OK, and southwest KS. Watch how convective intiation is forecast in the northeast TX Panhandle by 23z, with an explosion of supercells along a line from southern KS to northern KS overnight!
The operational WRF forecast CAPE and 0-1 km helicity for 00z Friday night are displayed below. Note the 2000+ J/kg CAPES and 150-200 helicity values in the same region as the simulated supercells in the left panel above. This all indicates the potential for STRONG tornadoes over this region late Friday and overnight.
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Friday Severe Wx Forecast Update
Posted At: February 22, 2007 @ 1:07 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
The 12z experimental high-resolution WRF does not forecast extensive convection until after 03z Friday night. The 3-hr accumulated precip. forecast for 00-03z and 03-06z are shown below, respectively.
The 00-03z precip forecast above hints at convective initiation around Altus sometime just after 00z, with light, elevated precip over central OK. After 03z, however, all hell breaks loose in central OK.
Still though, the presence of a very weak cap means that any SLIGHT increase in moisture or surface temperature than forecast by the above model would lead to much earlier convective initiation. And the huge low-level wind shear leads to a potentially volatile situation. We'll have to monitor the moisture return very closely...but we're planning on chasing this event regardless. Meanwhile, the SPC issued a moderate risk in their Thursday morning Day 2 Convective Outlook, mentioning the possibility of late afternoon initation in the extreme eastern TX Panhandle.
The 00-03z precip forecast above hints at convective initiation around Altus sometime just after 00z, with light, elevated precip over central OK. After 03z, however, all hell breaks loose in central OK.
Still though, the presence of a very weak cap means that any SLIGHT increase in moisture or surface temperature than forecast by the above model would lead to much earlier convective initiation. And the huge low-level wind shear leads to a potentially volatile situation. We'll have to monitor the moisture return very closely...but we're planning on chasing this event regardless. Meanwhile, the SPC issued a moderate risk in their Thursday morning Day 2 Convective Outlook, mentioning the possibility of late afternoon initation in the extreme eastern TX Panhandle.
SPC mentions large tornadoes for Friday...We guarantee violent needles.
Posted At: February 21, 2007 @ 12:11 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
Friday looks to be an INSANE day for tornadoes in western OK, with a 40-50 knot low-level jet Friday afternoon, increasing to 70+ knots by Friday evening. The result will be massive low-level shear in a thermodynamically-favorable environment. The SPC Day 3 Convective Outlook from Tuesday evening mentions "STRONG TORNADOES POSSIBLE FRIDAY EVENING".
The models are only increasing the low-level jet and moisture with each consecutive run. Shown below is the 12z Wed WRF forecast for Friday evening. Compare this with those of the previous post.
"TORNADOVIDEOS.NET IS PREDICTING AN EF-5!"
The models are only increasing the low-level jet and moisture with each consecutive run. Shown below is the 12z Wed WRF forecast for Friday evening. Compare this with those of the previous post.
"TORNADOVIDEOS.NET IS PREDICTING AN EF-5!"
TORNADOES POSSIBLE THIS WEEKEND!
Posted At: February 20, 2007 @ 11:05 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
A powerful early spring-like storm system will move across the southern U.S. this weekend, pumping unseasonable moisture northward from the Gulf of Mexico. The stage will be set for possible tornadoes, maybe an outbreak, on Friday and/or Saturday across the Southern Plains and south-central U.S respectively. Shown above is the WRF forecast CAPE and 850 mb flow for Friday afternoon. We'll definitely be chasing this event all the way to the Atlantic Ocean...so stay tuned!
Historic Nor'Easter Hammering Northeast on Valentines Day!
Posted At: February 14, 2007 @ 11:02 AM
Posted By: Reed Timmer
Related Categories: Snow
The first major Nor'easter of the year is battering the Northeast U.S. with insane snowfall rates and blizzard conditions. The "bomb cyclone" (deepening > 1 mb/hour for 24+hours) is forecast to intensify to 970 mb by tomorrow over the Canadian Maritimes. 15-30+ inches of snow will be widespread from central-upstate NY, VT, NH, ME, and MA with 40+ mph wind gusts.
Shown below is the WRF forecast 12-hr precip and mean sea level pressure forecast for 7 pm Wednesday night. Note the 2+ inches of water-equivalent precip expected over the period!
Shown below is the WRF forecast 12-hr precip and mean sea level pressure forecast for 7 pm Wednesday night. Note the 2+ inches of water-equivalent precip expected over the period!
Blizzard continues north...tornadoes in AL today...Fatal tornado in LA last night
Posted At: February 13, 2007 @ 6:39 PM
Posted By: Reed Timmer
Related Categories: General
Several tornadic supercells fired today in west-central AL, and produced at least 2 confirmed tornadoes and up to baseball size hail just west of Birmingham. The radar image below from around 5 pm CDT shows the AL supercells at peak intensity.
Blizzard warnings! IL, IN, OH
Posted At: February 13, 2007 @ 9:27 AM
Posted By: Reed Timmer
Related Categories: Snow
HEAVY snow has been hammering parts of MO, IL, IN, and OH overnight, with blizzard conditions expected for the rest of Tuesday. Meanwhile, the snow was beginning to move into the northeast, as bomb cyclogenesis begins just off shore over the Gulf Stream!
Posted below are some images taken by TornadoVideos.net storm chaser Dayna Timmer from Purdue University, which has received over a foot of snow as of 1 pm CST, with another 6-10" additional expected!
Posted below are some images taken by TornadoVideos.net storm chaser Dayna Timmer from Purdue University, which has received over a foot of snow as of 1 pm CST, with another 6-10" additional expected!
HUGE Winter Storm North - Tornadoes South!
Posted At: February 12, 2007 @ 2:58 PM
Posted By: Reed Timmer
Related Categories: General
A powerful storm system will sweep across the central U.S. early this week beginning Monday, Feb. 12, bringing up to two feet of snow from IN to ME, and possible tornadoes along the Gulf Coast. We'll keep you updated on any breaking news from this incredible storm! TV.net storm chasers are waiting for the heavy snow in central IN!
3-5 feet of snow possible at Tug Hill Plateau, NY
Posted At: February 3, 2007 @ 11:31 PM
Posted By: Reed Timmer
Related Categories: Snow
A historic lake effect event is underway to the east of Lakes Erie and Ontario, with 5+ inch per hour snowfall rates likely in the most intense bands. At 12:30 am EST, a STRONG lake effect band was pounding areas to the east of Lake Ontario near the Tug Hill Plateau, just north of Watertown. 3-5 FEET of snow is possible in this area by Monday morning!!
BLIZZARD continues in W. Michigan!
Posted At: February 3, 2007 @ 3:48 PM
Posted By: Reed Timmer
Related Categories: Snow
Heavy lake effect snow bands and 30-40 mph winds continue to pound parts of western Michigan. The GRR radar image as of ~5:00 pm EST shows the WNW flow lake effect bands streaming all the way into the center part of the state. The pictures below were taken by my sister, Cortney Timmer, from near Grand Rapids while a heavy snow band was passing through. 15-17 inches of snow had fallen from this storm, with more to come!
BLIZZARD WARNING in west MI!
Posted At: February 3, 2007 @ 12:31 PM
Posted By: Reed Timmer
Related Categories: Snow
Over a foot of lake effect snow has fallen over western Michigan over the last 24 hours, and wind gusts have exceeded 35 mph often. The pictures below are from just east of Grand Rapids, MI, where an additional foot of snow is possible by Sunday afternoon.
TORNADO EMERGENCY IN FLORIDA!
Posted At: February 2, 2007 @ 11:12 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
Deadly tornadoes struck central Florida between 2 and 4 am Friday, resulting in significant damage in Volusia, Lake, Sumter, and Seminole Counties. A State of Emergency has been declared in these areas, and sadly, 14 people have been reported dead as of 11:00 am Friday. Posted below is a radar image at around the time of the tornado. Note the classic supercell in central FL...This is the storm that produced the damaging tornado. Stay tuned for further updates.
INSANE LAKE EFFECT SNOWS!!!
Posted At: February 1, 2007 @ 1:34 PM
Posted By: Reed Timmer
Related Categories: Snow
INCREDIBLE lake effect snows (LES) continue downwind of the Great Lakes in MI, NY, and Ontario, Canada, with snowfall rates as high as 5-6" per hour in the most intense bands. Displayed below is a graphic describing the event on Thursday in southwest Michigan, followed by a brief explanation of LES.
Lake effect snow occurs as cold, moist wind flows over a large, relatively warm body of water, generating intense vertical motion, which organize into heavy lake effect snow bands under ideal conditions. As seen above, the residence time of the cold air over the lake is large with southwesterly flow, and a single convergence band often develops in southwest Michigan, as faster moving air over the lake experiences greater Coriolis Force, and has a more westerly component than the flow over land (due to decreased wind speeds from friction, and lesser Coriolis Force). Over a foot of new snow will likely fall in association with this intense lake effect band.
Areas in Ontario, Canada downwind of Lakes Superior and Huron often experience prolific lake effect storms. Displayed below are some images depicting these Canadian LES events, respectively. 2+ feet of snow are likely through this first weekend in Feb 2007 in these areas.
11:25 AM EST Thursday 1 February 2007
Snowsquall warning for
Searchmont - Montreal River Harbour - Batchawana Bay continued
Snow squalls today through Friday.
This is a warning that snowsqualls are imminent or occurring in these regions. Monitor weather conditions..Listen for updated statements.
An extended period of snow squall activity is setting up to the Lee of Lake Superior and Georgian Bay.
Cold southwest winds combined with weak ascent associated with an upper level disturbance is generating heavier flurries and snow squalls along the eastern shores of Lake Superior from Montreal River to the south of Wawa. The squall is particularly intense with snowfall rates in the 5 to 10 centimetre per hour range. This activity is expected to continue today and tonight and should tend to withdraw to fall over the lake on Friday. Since the snow squalls are expected to linger across the same area for a considerable length of time significant snowfall totals of 40 centimetres or more may be expected in the warned regions by Friday morning.
Lake effect snow occurs as cold, moist wind flows over a large, relatively warm body of water, generating intense vertical motion, which organize into heavy lake effect snow bands under ideal conditions. As seen above, the residence time of the cold air over the lake is large with southwesterly flow, and a single convergence band often develops in southwest Michigan, as faster moving air over the lake experiences greater Coriolis Force, and has a more westerly component than the flow over land (due to decreased wind speeds from friction, and lesser Coriolis Force). Over a foot of new snow will likely fall in association with this intense lake effect band.
Areas in Ontario, Canada downwind of Lakes Superior and Huron often experience prolific lake effect storms. Displayed below are some images depicting these Canadian LES events, respectively. 2+ feet of snow are likely through this first weekend in Feb 2007 in these areas.
Environment Canada's Official Weather Warnings
Warnings
Searchmont - Montreal River Harbour - Batchawana Bay11:25 AM EST Thursday 1 February 2007
Snowsquall warning for
Searchmont - Montreal River Harbour - Batchawana Bay continued
Snow squalls today through Friday.
This is a warning that snowsqualls are imminent or occurring in these regions. Monitor weather conditions..Listen for updated statements.
An extended period of snow squall activity is setting up to the Lee of Lake Superior and Georgian Bay.
Cold southwest winds combined with weak ascent associated with an upper level disturbance is generating heavier flurries and snow squalls along the eastern shores of Lake Superior from Montreal River to the south of Wawa. The squall is particularly intense with snowfall rates in the 5 to 10 centimetre per hour range. This activity is expected to continue today and tonight and should tend to withdraw to fall over the lake on Friday. Since the snow squalls are expected to linger across the same area for a considerable length of time significant snowfall totals of 40 centimetres or more may be expected in the warned regions by Friday morning.
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