Sydney Claridge Posted October 10, 2021 Share Posted October 10, 2021 Might as well start a thread for this event. We have a moderate risk, with a 15% hatched tornado probability across central Oklahoma. Quote SPC AC 100559 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun Oct 10 2021 Valid 101200Z - 111200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM SOUTHWEST THROUGH CENTRAL AND EASTERN OKLAHOMA... ...SUMMARY... A potentially significant severe weather event is forecast across a portion of Oklahoma into north Texas late this afternoon into the overnight. Severe storms capable of large to very large hail, a few strong tornadoes and damaging wind are expected. ...Southern Plains area... A vigorous shortwave trough situated near the Four Corners region will advance east through the southern Plains this afternoon and evening before reaching the lower to mid-MS Valley late tonight. In advance of this feature, a cold front now over the central Plains will move slowly south. By late afternoon this front will extend from a weak surface low in the southeast TX Panhandle or northwest TX, northeast through north central OK, southeast KS and northwest MO. This boundary will move slowly south into the evening. A dryline will extend southward from the surface low through west TX, but will eventually be overtaken by a Pacific cold front accompanying the progressive shortwave trough. Richer low-level moisture return is already underway with mid 60s F dewpoints approaching central TX. As temperatures warm through the 80s F along with modest mid-level lapse rates, up to 1500-2000 J/kg MLCAPE is likely by late afternoon. Initial storms should initiate over southwest OK or northwest TX along intersection of the dryline and the southwest-northeast oriented cold front. Given strength of effective bulk shear with 50+ kt associated with the approaching mid-upper jet, this activity should quickly become supercellular. Hodograph size should undergo a substantial increase as the low-level jet strengthens during the early evening with 0-1 km storm-relative helicity likely exceeding 250 m2/s2 by 00Z. Given the favorable kinematic and thermodynamic parameter space, potential exists for a couple of long track supercells to evolve and track east northeast through OK along and just south of the front. These storms will be capable of producing very large hail and strong tornadoes. Additional storms will likely develop farther northeast along this front as well farther south into TX as the Pacific front intercepts greater low-level moisture. These storms will also likely become supercells capable of all hazards. Eventually, storms may evolve into lines and clusters during the evening and into the overnight, but with a continued severe threat toward the lower and middle MS Valley regions. ...Upper Mississippi Valley and Great Lakes regions... A northern-stream shortwave trough will advance slowly northeast through northern MN during the day. Storms may increase over northeast MN just northeast of the vorticity maximum during the afternoon where wind profiles and modest instability will be sufficient for supercells. Primary threat with this activity will be hail and possibly a couple of brief tornadoes. Farther southeast across WI within the dry slot region, the extent of thunderstorm initiation during the day remains uncertain, but a conditionally favorable environment for supercells will exist. If confidence increases that robust updrafts can develop in this environment, then a categorical risk upgrade may be needed in later day 1 updates. ..Dial/Marsh.. 10/10/2021 2 1 Link to comment Share on other sites More sharing options...
cheese007 Posted October 10, 2021 Share Posted October 10, 2021 Can't say I expected a moderate risk tbh Link to comment Share on other sites More sharing options...
yoda Posted October 10, 2021 Share Posted October 10, 2021 Large ENH for Day 3 as well from S NE into NW Oklahoma Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 I'm in the Moderate Risk today . . . 1 Link to comment Share on other sites More sharing options...
It's Always Sunny Posted October 10, 2021 Share Posted October 10, 2021 Here is a good visualization of how today will materialize per the HRRR model. 2m dew points overlaid with 10m winds and reflectivity. You can see the surface cold front overrunning the dry line triggering tstms west of I-35. Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 Enhanced risk now includes DFW 1 Link to comment Share on other sites More sharing options...
It's Always Sunny Posted October 10, 2021 Share Posted October 10, 2021 8 minutes ago, Iceresistance said: Enhanced risk now includes DFW Yeah just saw that. Doesn't increase our tornado chances here though but wind chances now 30% which is reasonable. 1 Link to comment Share on other sites More sharing options...
cincy.wx Posted October 10, 2021 Share Posted October 10, 2021 surprisingly quiet in here for something that, at its surface, looks like a noteworthy day/evening ahead. thoughts on the setup? Link to comment Share on other sites More sharing options...
LoboLeader1 Posted October 10, 2021 Share Posted October 10, 2021 Link to comment Share on other sites More sharing options...
Powerball Posted October 10, 2021 Share Posted October 10, 2021 17 minutes ago, WXMan42711 said: surprisingly quiet in here for something that, at its surface, looks like a noteworthy day/evening ahead. thoughts on the setup? Given how lackluster this season has been, my expectations have been shot. 1 Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 It's really Windy outside, & my gut is telling me that today is going to be really bad News 9 said that they would not be surprised if there is a PDS TORNADO WATCH from the NWS Link to comment Share on other sites More sharing options...
Powerball Posted October 10, 2021 Share Posted October 10, 2021 For what little it's worth though, I think today's event is the first time this entire season that every short-term CAM has agreed on a single outcome, and they all look good for DFW. 2 Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 Moderate Risk bigger & farther North, also includes Tulsa, Bartlesville, & Stillwater Link to comment Share on other sites More sharing options...
OhioWX Posted October 10, 2021 Share Posted October 10, 2021 Latest mesoscale model runs have been very concerning and have trended towards more discrete activity in Oklahoma, notably threatening the Norman/Moore/OKC area and even up into Tulsa later on tonight. Latest SPC outlook expands the moderate risk to the north, putting the mentioned cities deeper within the 15% hatched tornado contour. In addition, DFW has now been included in the 10% tornado contour. Link to comment Share on other sites More sharing options...
Chinook Posted October 10, 2021 Share Posted October 10, 2021 The 15z HRRR has some big updraft helicity tracks right through Norman and other areas! Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 5 minutes ago, Chinook said: The 15z HRRR has some big updraft helicity tracks right through Norman and other areas! Also through Shawnee & even ends up at Tulsa Link to comment Share on other sites More sharing options...
SmokeEater Posted October 10, 2021 Share Posted October 10, 2021 . Sent from my SM-G973U using Tapatalk Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 This link would be EXTREMELY useful for tracking Supercells in Central Oklahoma, trust me . . . https://www.news9.com/nextgen-live-radar Link to comment Share on other sites More sharing options...
SmokeEater Posted October 10, 2021 Share Posted October 10, 2021 Meso out for W/C OK. Sent from my SM-G973U using Tapatalk 1 Link to comment Share on other sites More sharing options...
SmokeEater Posted October 10, 2021 Share Posted October 10, 2021 Tornado watch just issued, 90/70 tornado probs. Sent from my SM-G973U using Tapatalk 1 1 Link to comment Share on other sites More sharing options...
cheese007 Posted October 10, 2021 Share Posted October 10, 2021 2 minutes ago, SmokeEater said: Tornado watch just issued, 90/70 tornado probs. Sent from my SM-G973U using Tapatalk SEL7 URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 517 NWS Storm Prediction Center Norman OK 320 PM CDT Sun Oct 10 2021 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Much of Central and Southwest Oklahoma Western North Texas * Effective this Sunday afternoon and evening from 320 PM until 1000 PM CDT. * Primary threats include... Several tornadoes and a couple intense tornadoes likely Widespread damaging winds and isolated significant gusts to 85 mph likely Scattered large hail and isolated very large hail events to 2.5 inches in diameter likely SUMMARY...Severe thunderstorms are expected to rapidly develop this afternoon over southwest Oklahoma and race northeastward across the watch area. Supercells capable of strong tornadoes and significant wind damage are possible - especially along the I-44 corridor. The tornado watch area is approximately along and 70 statute miles north and south of a line from 50 miles west southwest of Altus OK to 40 miles northeast of Chandler OK. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 516... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 75 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 25040. ...Hart Link to comment Share on other sites More sharing options...
Iceresistance Posted October 10, 2021 Share Posted October 10, 2021 This is probably just shy of a PDS Tornado Watch. O_O Link to comment Share on other sites More sharing options...
OhioWX Posted October 10, 2021 Share Posted October 10, 2021 Special 20z OUN sounding. Once that cap erodes... Link to comment Share on other sites More sharing options...
jpeters3 Posted October 10, 2021 Share Posted October 10, 2021 15 minutes ago, OhioWX said: Special 20z OUN sounding. Once that cap erodes... A lot to erode in that sounding. Particularly, -170 J/kg of MLCIN is pretty prohibitive. This is quite a bit higher that CAM progs at the same time. I suspect we might have trouble getting CI anywhere away from the front/triple point. 2 Link to comment Share on other sites More sharing options...
Santa Clause Posted October 10, 2021 Share Posted October 10, 2021 That’s a lot if cap….. Link to comment Share on other sites More sharing options...
Powerball Posted October 10, 2021 Share Posted October 10, 2021 23 minutes ago, OhioWX said: Special 20z OUN sounding. Once that cap erodes... FWD's sounding isn't much better... Link to comment Share on other sites More sharing options...
SmokeEater Posted October 10, 2021 Share Posted October 10, 2021 Meso discussion out saying initiation is imminent with tornado threat increasing from SW to C OK. Sent from my SM-G973U using Tapatalk Link to comment Share on other sites More sharing options...
Powerball Posted October 10, 2021 Share Posted October 10, 2021 It seems the problem is that dewpoints are now starting to mix out. They've fallen into the mid 60s here. Link to comment Share on other sites More sharing options...
jpeters3 Posted October 10, 2021 Share Posted October 10, 2021 2 minutes ago, Powerball said: It seems the problem is that dewpoints are now starting to mix out. They've fallen into the mid 60s here. I doubt this will have much of an effect on things. The really shallow high Td layer near the surface would "mix out" anyway as air parcels ascend through the boundary layer into updrafts. What really matters is the average PBL moisture. Link to comment Share on other sites More sharing options...
cheese007 Posted October 10, 2021 Share Posted October 10, 2021 Mesoscale Discussion 1822 NWS Storm Prediction Center Norman OK 0425 PM CDT Sun Oct 10 2021 Areas affected...Southwest Oklahoma into western North Texas Concerning...Tornado Watch 517... Valid 102125Z - 102300Z The severe weather threat for Tornado Watch 517 continues. SUMMARY...Initiation of discrete storms is becoming more likely in the vicinity of Frederick, OK within the next 1-1.5 hours. The threat for tornadoes is increasing in southwest Oklahoma into parts of central Oklahoma. DISCUSSION...Towering cumulus continues to develop south of Frederick, OK. The strongest pressure falls in the last few hours have occurred in this vicinity. Confidence is increasing in storm initiation within the next 1-1.5 hours. Given the backed surface winds and over 50 kts of effective shear, initial storm mode will likely be supercellular. KFDR VWP has begun to show an increase in low-level SRH recently as well. Storms that form in this region would pose the greatest tornado risk over the next few hours. ..Wendt.. 10/10/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN... LAT...LON 33819849 33849879 33949902 34059910 34529892 34989844 35259790 35289751 35069737 34389761 33819849 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now