NewsSevere weather likely Sunday-Tuesday
Posted At: February 28, 2008 @ 1:07 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
The Storm Prediction Center has issued a risk for severe weather in their 4-8 Day Outlook for days 5 and 6, corresponding to Sunday/Monday, March 3/4. As mentioned, a strong trough is forecast to eject from the Rocky Mountain Region this weekend, and move across the central U.S. early next week. The 00z GFS run is more in line with the ECMWF with a slower progression of the trough. Despite a strong LLJ in the warm sector, it appears that a southward surging cold front will be a huge limiting factor for tornadoes on Sunday, unless the surface low is stronger than forecast. Monday looks to be a tornado outbreak over MS, AL, and GA, with 50+ knot LLJ and a very strong low-level cyclone. Instability will definitely not be a problem with this system, as the Gulf of Mexico is relatively untainted.
Tornadoes reported in Florida, heavy snow to the north
Posted At: February 26, 2008 @ 11:34 PM
Posted By: Reed Timmer
Related Categories: General
Two tornadoes were reported today in Florida, as several HP supercells moved through the area ahead of a strong cold front. Both tornadoes touched down in north-central Florida between 19 and 20 UTC, producing minor tree and structural damage. Meanwhile, the storm system responsible for the Florida tornadoes is producing very heavy snowfall and strong winds over New England, with significant northerly-flow lake effect across the Great Lakes Region.
Here is a radar loop from Northwest Indiana during 03-05 UTC showing a textbook single-band lake effect event off southern Lake Michigan. These single bands are formed from mesoscale convergence over the lake as faster, more veered flow meets the relatively backed flow from the land. The faster flow over the relatively "frictionless" lake surface curves slightly more to the right due to increased Coriolis Force relative to the land. The orientation of the resulting lake effect snow band depends on the wind direction in the low- to mid-levels of the atmosphere.
Winter Storm today/tonight from Iowa through the Great Lakes Region, severe weather possible south!
Posted At: February 25, 2008 @ 10:15 AM
Posted By: Reed Timmer
Related Categories: General
As a shortwave trough ejects from the Rocky Mountains and across the Great Plains today, a surface low will slowly deepen over the Southeast Plains, bringing winter storm conditions from Iowa eastward across the Great Lakes Region, and severe weather for the Arklatex overnight. The RUC forecast 500 mb and surface patterns for 00z this evening are displayed below:
6-8 inch snowfall accumulations are likely across the winter storm warning area across central/eastern IA into southern WI/northern IL, with slightly higher amounts possible from Lower Michigan eastward to New England as the system moves northeastward and the deformation zone becomes better developed. A battery of winter storm watches, warnings, and advisories are in effect for the cold side of this system, as shown in the SPC watch/warning map below:
Later tonight, as moist tropical air surges northward to the Arklatex region by 03z, severe weather will be possible with the approach of an upper-level jet streak ejecting from the base of the trough. The WRF and RUC models do not show the cap eroding until after 00z, so this will definitely be an overnight event. While CAPE values are forecast to be marginal, deep-layer shear will be sufficient for supercells. The LLJ looks a little veered for tornadoes, especially across the western part of the Slight Risk Area (see below), but tornadoes could be possible if storms can move into the more favorably low-level sheared environment further east. Stay tuned for updates as this severe weather event unfolds overnight.
6-8 inch snowfall accumulations are likely across the winter storm warning area across central/eastern IA into southern WI/northern IL, with slightly higher amounts possible from Lower Michigan eastward to New England as the system moves northeastward and the deformation zone becomes better developed. A battery of winter storm watches, warnings, and advisories are in effect for the cold side of this system, as shown in the SPC watch/warning map below:
Later tonight, as moist tropical air surges northward to the Arklatex region by 03z, severe weather will be possible with the approach of an upper-level jet streak ejecting from the base of the trough. The WRF and RUC models do not show the cap eroding until after 00z, so this will definitely be an overnight event. While CAPE values are forecast to be marginal, deep-layer shear will be sufficient for supercells. The LLJ looks a little veered for tornadoes, especially across the western part of the Slight Risk Area (see below), but tornadoes could be possible if storms can move into the more favorably low-level sheared environment further east. Stay tuned for updates as this severe weather event unfolds overnight.
Winter Storm hammering parts of the Northeast, including NYC!
Posted At: February 22, 2008 @ 10:42 AM
Posted By: Reed Timmer
Related Categories: Snow
5-9 inches of snow has already fallen across parts of eastern PA, northern NJ, and across the NYC Metro Area, with the highest totals reported from the Staten Island area. However, the precipitation has already begun changing over to sleet and freezing rain as an area of warm air just above the surface advects northward. The regional radar image from 16z show below as well as surface obs show the freezing line still off-shore the NYC Metro area, suggesting that ice accumulations will be a problem as the snow changes over to freezing rain.
A mesoscale discussion has been issued by the Storm Prediction Center for the likelihood of hourly ice accumulation rates approaching 0.10" per hour from eastern PA across the NYC Metro Area this afternoon. With up to 9 inches of snow already on the ground, the travel situation in this area could be ugly for the evening rush hour.
A mesoscale discussion has been issued by the Storm Prediction Center for the likelihood of hourly ice accumulation rates approaching 0.10" per hour from eastern PA across the NYC Metro Area this afternoon. With up to 9 inches of snow already on the ground, the travel situation in this area could be ugly for the evening rush hour.
Tornadoes in Louisiana today
Posted At: February 21, 2008 @ 5:54 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
An incredible long-track supercell has tracked across Southwest into Central Louisiana this afternoon and evening, with two tornadoes already reported near Lake Charles. This cell has occasionally exhibited strong rotation, and may have had a tornado on the ground as it crossed Interstate 49 south of Alexandria. Check out this storm in the radar loop below:
A mesoscale discussion has been issued for southeast Texas and southern Louisiana for the extension of Tornado Watch 70, mentioning the likelihood for tornadic supercells this evening and overnight. Stay tuned as this potentially dangerous situation unfolds.
A warm front has been lifting slowly northward across Louisiana, and is now passing through Shreveport in the northwest part of the state. CAPE values along and south of the warm front are in the 1500-2000 J/kg range, with 0-1 km helicities of 150-200 m2/s2 and will only increase as the low-level jet intensifies tonight, thus, strong tornadoes are possible with any discrete supercells. The RUC analysis below shows the CAPE and 0-1 km helicity values as of 2300 UTC.
Across the Ozark Mountain region and Ohio River Valley, ice storm warnings are in effect as warm, moist air is lifted up and over a shallow Arctic airmass at the surface. Downed trees and power outages will be common across this area. Additionally, winter storm warnings and watches are in effect across the Mid-Atlantic and southern New England.
A mesoscale discussion has been issued for southeast Texas and southern Louisiana for the extension of Tornado Watch 70, mentioning the likelihood for tornadic supercells this evening and overnight. Stay tuned as this potentially dangerous situation unfolds.
AMAZING lunar eclipse photos by Dick McGowan!
Posted At: February 21, 2008 @ 1:38 AM
Posted By: Reed Timmer
Related Categories: General
Check out these amazing pictures of last night's (Feb 20, 2008) lunar eclipse taken by Dick McGowan near the Kansas City area. See Dick's blog at www.stackedplates.blogspot.com for more still pictures of this incredible event!
Incredible video of the Prattville, AL EF3 tornado!
Posted At: February 19, 2008 @ 10:42 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
Check out this video taken by a local resident of Prattville, AL as he was nearly within the circulation of the 1/4 mile wide EF3 tornado that devastated parts of this community just north of Montgomery, AL. It appears that this video was just now uploaded to Youtube since it only has 11 views at the time of this post!
Initial tornado damage surveys from yesterday in FL/AL/GA
Posted At: February 18, 2008 @ 4:59 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
Unofficially, 44 tornadoes were reported with yesterday's tornado outbreak across AL, GA, and the FL Panhandle, and the initial damage surveys are just now becoming available. A majority of the tornadoes were produced by two supercells: one that moved from the Gulf of Mexico across the western FL Panhandle, and through southeast AL into central GA, and a second that ravaged communities west and north of Montgomery, AL. These supercell tracks are clearly evident in the SPC storm reports map below:
The radar loop below (1900-2100 UTC) shows these two supercells at their peak intensity, and are highlighted midway through. The first supercell, that damaged the small community of Molino, FL, developed well ahead of the main convective band, and had a strong mesocyclone for over 7 hours! This cell had unimpeded access to the uncapped warm sector and 500+ 0-1 km helicities, and thus it is not surprising this storm produced several damaging tornadoes. The strongest tornado of the day was actually produced by the cell that moved from southwest AL through just north of Montgomery, AL before dissipating in east-central AL.
According to initial damage surveys from the Birmingham NWS, the latter mentioned supercell produced EF3 damage in the community of Prattville, AL, just to the northwest of Montgomery. As stated below, this tornado was up to 450 yards wide with estimated wind speeds of over 150 mph. 200 homes and 40 businesses were destroyed by this wedge (likely), but incredibly, there were no fatalities reported. In fact, there were zero fatalities from this entire tornado outbreak!
The damage assessment for the Prattville tornado is displayed below:
The radar loop below (1900-2100 UTC) shows these two supercells at their peak intensity, and are highlighted midway through. The first supercell, that damaged the small community of Molino, FL, developed well ahead of the main convective band, and had a strong mesocyclone for over 7 hours! This cell had unimpeded access to the uncapped warm sector and 500+ 0-1 km helicities, and thus it is not surprising this storm produced several damaging tornadoes. The strongest tornado of the day was actually produced by the cell that moved from southwest AL through just north of Montgomery, AL before dissipating in east-central AL.
According to initial damage surveys from the Birmingham NWS, the latter mentioned supercell produced EF3 damage in the community of Prattville, AL, just to the northwest of Montgomery. As stated below, this tornado was up to 450 yards wide with estimated wind speeds of over 150 mph. 200 homes and 40 businesses were destroyed by this wedge (likely), but incredibly, there were no fatalities reported. In fact, there were zero fatalities from this entire tornado outbreak!
The damage assessment for the Prattville tornado is displayed below:
According to initial assessments from the Mobile NWS, the Molino tornado was given an EF1 rating, with scattered EF1 damage assigned throughout the path of the supercell. However, it is unknown whether this was from a single long-track tornado or several intermittent touchdowns. Hopefully this information will become available soon. Stay tuned for updates as the damage assessments are completed...
Strong tornadoes possible today along the Central Gulf Coast!
Posted At: February 17, 2008 @ 8:09 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
As the system responsible for yesterday's embarrassing chase moves east across the Southern U.S. today, several bands of convection will move through the Central Gulf Coast along and ahead of the cold front. With a 40-50 knot LLJ ahead of the cold front, low-level shear will be favorable for tornadoes with any discrete supercells that forum. The LLJ may be a bit veered for strong tornadoes today, but a small change in surface wind and/or storm motion could easily change that. The RUC forecast CAPE and 850 mb pattern for 22z (4:00 pm CST) are displayed below:
While we may be in a bit of a lull in the convective activity across the Central Gulf Coast as of 8:00 am CST, a tornado watch is still in effect until 1:00 pm for much of southern AL and extreme southeastern MS. However, further convective development is anticipated by late morning/early afternoon across this region.
Given the relatively large uncapped and sufficiently unstable warm sector ahead of this cold front, as well as the immense low-level shear, the Storm Prediction Center has issued a 10% area for tornadoes, with a hatched area for possible strong tornadoes as well. Stay tuned for more updates as this severe weather event unfolds!
While we may be in a bit of a lull in the convective activity across the Central Gulf Coast as of 8:00 am CST, a tornado watch is still in effect until 1:00 pm for much of southern AL and extreme southeastern MS. However, further convective development is anticipated by late morning/early afternoon across this region.
Given the relatively large uncapped and sufficiently unstable warm sector ahead of this cold front, as well as the immense low-level shear, the Storm Prediction Center has issued a 10% area for tornadoes, with a hatched area for possible strong tornadoes as well. Stay tuned for more updates as this severe weather event unfolds!
Tornado Outbreak possible in South Texas!
Posted At: February 16, 2008 @ 12:46 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
As a strong vorticity maximum ejects from the Mexican Plateau on Saturday and encounters the deep tropical moisture in place over South Texas, supercells will be likely with the potential for strong tornadoes. 0-1 km helicity values of 300+ m2/s2 will be in place east of the cold front/dryline in an unstable and uncapped warm sector, so if storms can remain discrete, a tornado outbreak will be likely. We're departing in about an hour for a target in South Texas. Stay tuned for updates as this potentially dangerous situation unfolds.
Ice Storm moving into Central OK!
Posted At: February 15, 2008 @ 8:35 PM
Posted By: Reed Timmer
Related Categories: Snow
A small but heavy area of freezing precipitation has moved from Southwest into Central Oklahoma this evening, with over 1/4 inch ice accumulations possible where the heaviest thunderstorms reside. Temperatures are in the upper 20s to lower 30s across the region, with warm advection and relatively warm temperatures moving northward just above the surface. The result is a textbook freezing rain event including the OKC Metro area. A radar loop from around 8:30 pm CST is shown below:
Winter storm warnings have been issued over West Texas and western Oklahoma for this initial wave of precipitation tonight, and for heavy snowfall in association with the upper storm system tomorrow. Moderate ice accumulations are expected over southwest into central OK this evening, with 4+ inches of snow likely by tomorrow night across the TX Panhandle and Northwest OK.
Winter storm warnings have been issued over West Texas and western Oklahoma for this initial wave of precipitation tonight, and for heavy snowfall in association with the upper storm system tomorrow. Moderate ice accumulations are expected over southwest into central OK this evening, with 4+ inches of snow likely by tomorrow night across the TX Panhandle and Northwest OK.
Texas tornado outbreak possible on Saturday!
Posted At: February 15, 2008 @ 12:40 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
As a potent shortwave trough moves through the Southern Rocky Mountain Region on Saturday, deep tropical moisture will surge northward into central Texas with 50-60 knot low level jet. A mid-level dry slot will rotate around the base of the trough at around peak heating, allowing for the warm sector to destabilize to unseasonable levels. Given the very large unstable and uncapped warm sector across Central and South Texas on Saturday, and incredible low-level shear, the potential exists for a significant tornado outbreak this weekend. Check out the WRF forecasts for CAPE and 850 mb for Saturday evening below:
Based on this evening's model runs, which are consistent with previous runs, the Storm Prediction Center has decided to go with a moderator risk for Central and South Texas in their Day 2 outlook for Saturday. We will definitely be chasing this event, as I'm sure many others will be as well, so stay tuned for updates!
Major Nor'Easter pounding New England and the Canadian Maritimes
Posted At: February 13, 2008 @ 9:55 AM
Posted By: Reed Timmer
Related Categories: Snow
A coastal low pressure system will deepen today just off the coast of New England, producing substantial amounts of rain, ice, and snow across the Northeast U.S. and the Canadian Maritimes. Northern New England will see the brunt of the snowfall, especially across the higher elevations, with over a foot of accumulation possible. Many areas in the valleys and lower elevations in central/northern New England will receive significant ice accumulations, with over 1/2 inch of accumulation possible. As the low pressure area deepens this afternoon/evening and moves towards Cape Cod, winds will increase across the region, leading to power outages in the hardest hit areas from ice. A regional radar loop from this morning is shown below:
The RUC forecast for 2300 UTC this evening shows the low pressure center just west of Cape Cod, with an MSLP of 996 mb. While this doesn't seem like a very deep system based on surface pressure, it is a fairly strong system when viewed relative to the surrounding anticyclones. Stay tuned for updates on the snowfall and ice totals from this textbook coastal storm.
The RUC forecast for 2300 UTC this evening shows the low pressure center just west of Cape Cod, with an MSLP of 996 mb. While this doesn't seem like a very deep system based on surface pressure, it is a fairly strong system when viewed relative to the surrounding anticyclones. Stay tuned for updates on the snowfall and ice totals from this textbook coastal storm.
Tornadoes likely south, winter storm to the north!
Posted At: February 12, 2008 @ 2:39 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
A potent shortwave trough is currently moving through the Great Lakes Region, with a strong trailing cold front extending southwestward toward the Central Gulf Coast. Deep tropical moisture has been advected as far north as central AL, with dewpoints in the low 60s along the Gulf Coast. While storms have been exhibiting mainly linear structure so far, there have been areas of rotation indicated within embedded supercells in the line, and also with storms out ahead of the front. Three tornado watches are in effect for Southern Louisiana and Alabama, and also the Florida Peninsula. Winter storm warnings are also in effect for much of New England, where over a foot of snow could fall especially over the higher elevations.
A strong low-level jet has developed to the east of the low-level cyclone, with the strongest 850 mb winds north of the deep moisture across Tennessee and Kentucky. Further south, where the deeper moisture resides, the low-level jet is generally below 40 knots, but still sufficient for brief tornadoes. The 18z RUC Analyses for mslp and 850 mb are shown below.
Please check out the forum (linked above) for further discussion of this event.
A strong low-level jet has developed to the east of the low-level cyclone, with the strongest 850 mb winds north of the deep moisture across Tennessee and Kentucky. Further south, where the deeper moisture resides, the low-level jet is generally below 40 knots, but still sufficient for brief tornadoes. The 18z RUC Analyses for mslp and 850 mb are shown below.
Please check out the forum (linked above) for further discussion of this event.
Check out the new TornadoVideos.net web design!
Posted At: February 11, 2008 @ 9:43 PM
Posted By: Reed Timmer
Related Categories: General
Jason has put a lot of work into the new TornadoVideos.net web design, and we'd like to get your feedback on the updates! Changes include a wider, more "Web 2.0" look, new banner and color scheme, and also a new background!
The forum will also be changing significantly, so please be patient and we'll re-initiate the registrations. In addition to a new design, the forum will also be organized differently, and will also have a chat feature!
Stay tuned for more updates!!
The daily blog posts will start up again tomorrow as well...We've been insanely busy with the recent updates.
Thanks for your continued participation in this growing weather community!
The forum will also be changing significantly, so please be patient and we'll re-initiate the registrations. In addition to a new design, the forum will also be organized differently, and will also have a chat feature!
Stay tuned for more updates!!
The daily blog posts will start up again tomorrow as well...We've been insanely busy with the recent updates.
Thanks for your continued participation in this growing weather community!
Amazing video of the Memphis, TN tornado!
Posted At: February 10, 2008 @ 1:32 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
Check out this INCREDIBLE video of the Memphis tornado on February 5, just as the EF2 twister was touching down in Southaven, MS at around 5:30 pm CST. Note the textbook suction vortex at the beginning of the video!
Tornado video from Izard County, AR
Posted At: February 8, 2008 @ 9:53 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
After a quick response team survey the damage today from Atkins to Clinton to Mountain View to Highland, AR, it has been concluded that this damage path was likely from a single tornado. The rating has also been upgraded to EF4. Here is video of the Izard County, AR tornado from around 6:20 pm CST the evening of February 5, followed by the public information statement with the tornado rating upgrade.
Damage assessments from Feb 5, 2008 tornado outbreak
Posted At: February 8, 2008 @ 10:11 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
Here is a summary of the damage surveys produced by the affected National Weather Service offices from the February 5, 2008 tornado outbreak. The NWS offices included are Huntsville, AL; Nashville, TN; Memphis, TN; Paducah, KY; and Little Rock, AR. The information here will be updated as the final damage assessments are posted. Shown below is a graphical summary of the entire outbreak front the Storm Prediction Center:
- read complete story.....
Damage pictures from the Zion, AR tornado
Posted At: February 6, 2008 @ 11:21 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
Here are damage photos from the violent wedge tornado that devastated Zion, AR, courtesy of local resident Heidi Farrar. The damage path of this tornado reached a width of nearly a mile at times, with early rating estimates of EF3 to EF4 at the hardest hit areas. According to Heidi, the tornado must have lifted slightly at times, since only tree tops are damaged in certain areas.
Sadly, the death toll has now reached 54 from this event, making it the deadlest tornado outbreak in the United States in the last 20 years. There are many incredible survivor stories, including a Union College student in Jackson, TN who was trapped under a massive concrete slab after being sucked out of the dorm by the violent tornado.
Sadly, the death toll has now reached 54 from this event, making it the deadlest tornado outbreak in the United States in the last 20 years. There are many incredible survivor stories, including a Union College student in Jackson, TN who was trapped under a massive concrete slab after being sucked out of the dorm by the violent tornado.
Devastating tornado outbreak ravages Arkansas, Tennessee, and Kentucky
Posted At: February 6, 2008 @ 4:59 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
As anticipated, a devastating tornado outbreak ravaged parts of the Ozark Mountain Region and the southern Mississippi River Valley yesterday, with 67 tornadoes reported across 7 states as of early this morning (Wednesday). The most damaging tornadoes occurred across northern Arkansas, with a near continuous damage path from Atkins to northeast of Ash Flat; Southeast Memphis, TN, where the Hickory Ridge Mall and Airport sustained severe damage; Jackson, TN, which has been hit multiple times by tornadoes over the last 5 years; and also western KY and northern AL. Sadly, 27 people have lost their lives from this tornado outbreak, with more than 100 injured. Here are some links regarding this event:
http://www.msnbc.msn.com/id/23006771/
http://www.cnn.com/2008/US/weather/02/06/tornadoes/index.html
Pictures of the tornadoes (thanks Derek!):
http://arkansasmatters.com/content/photos/weatherevents
The unofficial SPC Storm Reports map for this historic outbreak is displayed below:
We chased yesterday in Arkansas, and intercepted the tornadic supercell that moved out of northern LA and across southeast AR just south of Dumas. We observed a massive rotating wall cloud and near tornadogenesis, but were forced to give up the pursuit as the storm crossed the MS River. Based on radar, this storm must have produced a tornado just on the other side of the river.
ViolentPlains.com intercepted the destructive Atkins, AR stovepipe about 1.5 miles south of I-40 just before 5:00 pm CST. This same storm, and possibly even the same tornado, continued to the northeast and caused extreme devastation in many communities of north/northeast AR, including Clinton, Mountain View, Ash Flat, and Zion. As Heidi mentioned in the previous post, a large, damaging tornado from this supercell thankfully missed her home by 2.5 miles!
A video compilation of the Southeast AR supercell and the Atkins, AR stovepipe (courtesy of ViolentPlains.com can be found below:
Stay tuned for updates as more information becomes available.
http://www.msnbc.msn.com/id/23006771/
http://www.cnn.com/2008/US/weather/02/06/tornadoes/index.html
Pictures of the tornadoes (thanks Derek!):
http://arkansasmatters.com/content/photos/weatherevents
The unofficial SPC Storm Reports map for this historic outbreak is displayed below:
We chased yesterday in Arkansas, and intercepted the tornadic supercell that moved out of northern LA and across southeast AR just south of Dumas. We observed a massive rotating wall cloud and near tornadogenesis, but were forced to give up the pursuit as the storm crossed the MS River. Based on radar, this storm must have produced a tornado just on the other side of the river.
ViolentPlains.com intercepted the destructive Atkins, AR stovepipe about 1.5 miles south of I-40 just before 5:00 pm CST. This same storm, and possibly even the same tornado, continued to the northeast and caused extreme devastation in many communities of north/northeast AR, including Clinton, Mountain View, Ash Flat, and Zion. As Heidi mentioned in the previous post, a large, damaging tornado from this supercell thankfully missed her home by 2.5 miles!
A video compilation of the Southeast AR supercell and the Atkins, AR stovepipe (courtesy of ViolentPlains.com can be found below:
Stay tuned for updates as more information becomes available.
High Risk issued this morning -- Tornado outbreak looming!
Posted At: February 5, 2008 @ 12:10 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
A classic MS River Valley tornado outbreak is about to begin from southern Arkansas northeast to western Kentucky. Unseasonable moisture values, incredible wind shear, and a large uncapped warm sector will set the stage for potentially record-breaking tornado outbreak beginning in the next few hours. We are currently sitting just east of Little Rock, monitoring the pre-frontal convection to our southwest. The temperature is around 70 with dewpoints well in the 60s! A vast difference compared to the mid-30s we left in Norman, OK this morning. Hopefully we'll avoid the decoy storms! Stay tuned for updates!
Tornado Outbreak likely today!
Posted At: February 5, 2008 @ 4:59 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
Since we're about ready to head out the door for our target area, I don't have much time to go into detail, but very little has changed since yesterday morning. A potentially significant tornado outbreak still seems likely given the massive uncapped warm sector and widespread 250+ m2/s2 0-1 km helicities from extreme Northeast Texas to as far north as southern Indiana. The Storm Prediction Center has issued a moderate risk in their initial Day 1 Outlook, with the possibility of being upgraded to a High Risk. We'll have the tracker up and running for as long as we have data connection, and stay tuned for updates as this dangerous weather situation unfolds.
Major tornado outbreak likely tonight through tomorrow!
Posted At: February 4, 2008 @ 9:54 AM
Posted By: Reed Timmer
Related Categories: Tornadoes
A severe weather outbreak is likely tonight through tomorrow from the eastern Southern Plains east to the Mississippi River Valley (Southern IL southward). The models have been trending slower and slower with this system with each consecutive run, with the WRF now forecasting the dryline to cross the I-35 corridor late tomorrow (Tuesday) morning. Therefore, the severe weather threat for today will hold off until after dark when the upper-level support arrives. Beginning early tomorrow afternoon, or even late tonight, the threat for tornadoes will increase dramatically over Northeast TX, East OK, and AR as supercells become surface-based. Given 0-1 km helicity values of 200+ m2/s2 over the entire warm sector, these tornadoes could be strong and long-track (especially with the fast storm motions). Selected WRF forecast panels for 00z tomorrow are displayed below.
As is commonly the case with this type of event, the core of the LLJ and the best low-level shear will be slightly east of the dryline and the best instability, as can be seen in the CAPE and 850 mb forecasts above. However, this area still has little or no capping inversion despite lesser CAPE, and is still supportive of strong tornadoes. A likely scenario for tomorrow's severe weather event is the development of two bands of supercells: one over Arkansas and northern Louisiana along a pre-frontal confluence line early in the afternoon, and a second along the dryline further west across eastern Oklahoma and extreme Northeast Texas. The eastern supercells will likely have the highest potential of producing long-track strong tornadoes given the very high 0-1 km helicity values, but tornadoes cannot be ruled out along the dryline as well. The dryline storms will also move rapidly eastward into the higher low-level shear as the day progresses, anyway, so either target seems logical from a storm chasing perspective.
A moderate risk was issued last night by the Storm Prediction Center in their Day 2 Outlook over the southern MS River Valley and eastward, but this area will definitely be shifted significantly west in the next outlook -- probably including most of AR and maybe even Eastern OK and Northeast TX. We'll definitely be chasing this event, and will keep you updated as more model runs become available!
As is commonly the case with this type of event, the core of the LLJ and the best low-level shear will be slightly east of the dryline and the best instability, as can be seen in the CAPE and 850 mb forecasts above. However, this area still has little or no capping inversion despite lesser CAPE, and is still supportive of strong tornadoes. A likely scenario for tomorrow's severe weather event is the development of two bands of supercells: one over Arkansas and northern Louisiana along a pre-frontal confluence line early in the afternoon, and a second along the dryline further west across eastern Oklahoma and extreme Northeast Texas. The eastern supercells will likely have the highest potential of producing long-track strong tornadoes given the very high 0-1 km helicity values, but tornadoes cannot be ruled out along the dryline as well. The dryline storms will also move rapidly eastward into the higher low-level shear as the day progresses, anyway, so either target seems logical from a storm chasing perspective.
A moderate risk was issued last night by the Storm Prediction Center in their Day 2 Outlook over the southern MS River Valley and eastward, but this area will definitely be shifted significantly west in the next outlook -- probably including most of AR and maybe even Eastern OK and Northeast TX. We'll definitely be chasing this event, and will keep you updated as more model runs become available!
Severe weather outbreak likely early next week!
Posted At: February 2, 2008 @ 4:28 PM
Posted By: Reed Timmer
Related Categories: Tornadoes
A massive trough will plow across the U.S. through the middle of next week, with springtime moisture advecting northward by Monday intro the southeastern Plains ahead of a strong dryline. Given intense deep-layer and low-level wind shear ahead of this trough, supercells will be possible on Monday across eastern OK, southeastern KS, AR, and southern MO, and into the Central Gulf Coast states by Tuesday. GFS forecast loops from Sunday through Wednesday morning for 500 mb and dewpoint are shown below:
The Storm Prediction Center has issued a slight risk in their Day 2 Outlook from extreme Northeast Texas to the Bootheel of MO for severe weather east of the textbook dryline on Monday, with a risk for severe weather included for Tuesday in their extended outlook. If these model runs verify, Monday through Tuesday will likely be our first chase of the year! Hopefully we'll make up for missing the Southwest MO hoses.
Major winter storm pounding the Great Lakes/Northeast
Posted At: February 1, 2008 @ 9:26 AM
Posted By: Reed Timmer
Related Categories: Snow
A major winter storm is still pounding parts of the Great Lakes Region and the Northeast on Saturday morning, with very heavy snow across IL, IN, Lower MI, and into Southern Ontario, and intense freezing rain across Pennsylvania, and New York State. 6-12+ inches have fallen or are expected to fall in the aforementioned heavy snow areas, with over 1/2 inch of ice accumulations in the warm sector where warm air is pumping northward over cold air at the surface. The national radar loop below from Saturday morning shows the storm in its entirety:
When first glancing at the RUC-forecast MSLP map below, it appears that the storm system responsible for this massive precipitation shield is rather weak, with a minimum pressure of 1007 mb. However, this cyclone is relatively intense when compared to the 1043 mb anticyclone to the northeast across the Canadian Maritimes! - read complete story.....
When first glancing at the RUC-forecast MSLP map below, it appears that the storm system responsible for this massive precipitation shield is rather weak, with a minimum pressure of 1007 mb. However, this cyclone is relatively intense when compared to the 1043 mb anticyclone to the northeast across the Canadian Maritimes! - read complete story.....
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