April 2-8, 2023 | Severe Storms

[StormfanaticInd]

Strongly worded moderate risk for the south in the latest update 

ARKLATEX INTO SOUTHERN MO/IL TONIGHT  

  

BY EARLY EVENING, FORECAST SOUNDINGS FROM MOST 12Z GUIDANCE SHOWS  

THAT A BROAD AREA OF HIGH CONDITIONAL RISK OF TORNADIC SUPERCELLS  

WILL DEVELOP FROM EASTERN OK INTO MUCH OF AR AND SOUTHERN MO. THIS  

AREA WILL STILL BE SOMEWHAT CAPPED AND THE MECHANISMS FOR CONVECTIVE  

INITIATION ARE UNCERTAIN. HOWEVER, A CONSENSUS OF GUIDANCE SHOWS  

MULTIPLE CLUSTERS OF SUPERCELLS FORMING ACROSS THIS AREA AND  

PERSISTING THROUGH THE EVENING. WIND FIELDS WILL STRENGTHEN  

THROUGHOUT THE NIGHT AND CAPPING WILL WEAKEN, LEADING TO A SERIOUS  

CONCERN FOR NOCTURNAL TORNADOES OVER THE SOUTHERN MDT RISK AREA IN  

MO/AR. AGAIN, MODEL GUIDANCE PROVIDES CONFIDENCE IN THE RISK OF  

WIDELY SCATTERED SUPERCELLS THROUGHOUT THE NIGHT ACROSS THE AREA,  

ALTHOUGH DETAILS OF LOCATION AND TIMING ARE UNCERTAIN. STRONG OR  

EVEN VIOLENT TORNADOES ARE POSSIBLE IN THIS SCENARIO.  

  

Edited April 4, 2023 by StormfanaticInd

[Neoncyclone]

Definitely going to be dealing with some dry air today, OUN sounding from 12Z, very shallow moist layer with lots of dry air through the mid-levels this type of environment is going to be advecting into the warm sector later, and could definitely keep the severe threat limited in some areas.

Further south in the DFW the EML is in full force, this is what will keep storms in Arkansas from forming most of the day as this environment advects ENE and why we've been talking about the southern mode being a night-time event. dry mid-levels with a very shallow moist layer also being shown in DFW.

 

Pretty complex forecast today but the high-ceiling potential is still there, going to be interesting to watch the evolution of today.

 

Edited April 4, 2023 by Neoncyclone

[Hoosier]

What happened this morning in Moline with the 90 mph gust is reminiscent of what happened there on 3/12/2006.  In that case, they had a 107 mph gust with temps in the 40s.  Today it was 90 mph with temps in the low 50s.  In both cases you would've thought there would be enough low level stability to prevent such extreme gusts, but it goes to show that severe winds can sometimes punch through a stable layer.

[Ingyball]

Looks like the dryline isn't pushing east as fast like the NAM expected. HRRR seems to be trending that way as well. Speed of the front will be important now to see how far west that dryline retreats after sunset. 

[snowlover2]

Updated day2 looks unchanged.

[nwohioweather]

4 minutes ago, snowlover2 said:

Updated day2 looks unchanged.

I think the 30% Wind Parameters expanded, especially towards the north.

[Snow____]

49 minutes ago, Hoosier said:

What happened this morning in Moline with the 90 mph gust is reminiscent of what happened there on 3/12/2006.  In that case, they had a 107 mph gust with temps in the 40s.  Today it was 90 mph with temps in the low 50s.  In both cases you would've thought there would be enough low level stability to prevent such extreme gusts, but it goes to show that severe winds can sometimes punch through a stable layer.

It’s a rarity but I’ve had some impressive thunderstorms with temps in the upper 30’s before… it’s always odd getting a thunderstorm when it’s cold but it can happen and it’s pretty cool. 

[Snow____]

Starting to get interested about tomorrow. I’m just hoping to get some good storms tomorrow. Sucks I have some festivities to attend to tomorrow night so I won’t be as invested but maybe some good storms can come through before then.

[Iceresistance]

3 minutes ago, Snow____ said:

It’s a rarity but I’ve had some impressive thunderstorms with temps in the upper 30’s before… it’s always odd getting a thunderstorm when it’s cold but it can happen and it’s pretty cool. 

Yeah, there was Walnut sized hail in Oklahoma a few years ago when it was 33

[Iceresistance]

48 minutes ago, Ingyball said:

Looks like the dryline isn't pushing east as fast like the NAM expected. HRRR seems to be trending that way as well. Speed of the front will be important now to see how far west that dryline retreats after sunset. 

I really don't like it when there is a slower dryline, that OUN sounding featured high parameters, but the EML makes is somewhat conditional.

[StormfanaticInd]

Severe storms now forming in Missouri 👀

[StormfanaticInd]

 

[StormfanaticInd]

 

[Ingyball]

The dry line finally made it through here. It's still struggling to push east of the Kansas Turnpike (I-35) where dew points are in the 50s. Have to wonder if unexpected cloud cover has limited mixing some. Should still clear the Turnpike but chances are increasing that areas along and east of the Turnpike will see that line of storms as it forms. 

[Iceresistance]

9 minutes ago, Ingyball said:

The dry line finally made it through here. It's still struggling to push east of the Kansas Turnpike (I-35) where dew points are in the 50s. Have to wonder if unexpected cloud cover has limited mixing some. Should still clear the Turnpike but chances are increasing that areas along and east of the Turnpike will see that line of storms as it forms. 

Yeah, there are storms north of DFW right now...

EDIT: It looks like the dryline actually retreated west along and south of I-40.

Edited April 4, 2023 by Iceresistance

[StormfanaticInd]

New tornado watch now up

 

Edited April 4, 2023 by StormfanaticInd

[ElectricStorm]

80/60 tor probs 

[Neoncyclone]

1 minute ago, StormfanaticInd said:

New tornado watch now up

Quote

SEL5

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Tornado Watch Number 115
   NWS Storm Prediction Center Norman OK
   250 PM CDT Tue Apr 4 2023

   The NWS Storm Prediction Center has issued a

   * Tornado Watch for portions of 
     Central and Southeast Iowa
     Northwest Illinois
     Northern Missouri

   * Effective this Tuesday afternoon and evening from 250 PM until
     1000 PM CDT.

   * Primary threats include...
     Several tornadoes and a couple intense tornadoes likely
     Widespread large hail and isolated very large hail events to 3.5
       inches in diameter likely
     Scattered damaging wind gusts to 70 mph likely

   SUMMARY...Intense thunderstorms will increase in coverage this
   afternoon across the watch area, with supercells expected.  Very
   large hail and tornadoes may occur in the strongest cells.

   The tornado watch area is approximately along and 110 statute miles
   north and south of a line from 50 miles west northwest of Lamoni IA
   to 45 miles south southeast of Moline IL. For a complete depiction
   of the watch see the associated watch outline update (WOUS64 KWNS
   WOU5).

   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 114...

   AVIATION...Tornadoes and a few severe thunderstorms with hail
   surface and aloft to 3.5 inches. Extreme turbulence and surface wind
   gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
   storm motion vector 25035.

   ...Hart

 

[Neoncyclone]

Just incase you were convinced that this event isn't stupidly complex

Quote

Mesoscale Discussion 0458
   NWS Storm Prediction Center Norman OK
   0306 PM CDT Tue Apr 04 2023

   Areas affected...portions of North Texas...eastern
   Oklahoma...western Arkansas into southwestern Missouri and
   southeastern Kansas

   Concerning...Severe potential...Watch possible 

   Valid 042006Z - 042200Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorms may pose a risk initially for hail across
   portions of North TX/OK into portions of western AR. Additional
   development along the dryline is possible in eastern KS and western
   MO. Uncertainty on the exact timing and location of storm
   development is very high. Trends are being monitored for a possible
   weather watch.

   DISCUSSION...As of 2000 UTC, afternoon observations showed a broad
   plume of cirrus, associated with a deep western US trough,
   overspreading a warming and moistening air mass across much of the
   ArkLaTex and southern Plains. Within the broad cirrus, several CI
   attempts have been noted along and east of a confluence band ahead
   of the dryline in North TX. Surface temperatures near 80 and
   dewpoints in the upper 60s to low 70s F are supporting moderate
   instability with MLCAPE of 2000 J/kg. With the main trough lagging
   to the west, forcing for ascent is rather nebulous over much of the
   region through the afternoon. This is evident in SPC mesoanalysis
   which shows considerable inhibition still in place below a robust
   EML. Despite the inhibition, strong flow aloft is supporting long
   elongated hodographs with effective shear of 50-60 kt favorable for
   supercells with the potential for large hail. Weaker low-level shear
   may limit the initial tornado threat if supercells are able to
   mature. However as forcing increases toward the evening, a greater
   threat for tornadoes may evolve.

   Recent visible and radar trends show several weak, likely elevated 
   updrafts over the Red river are persisting despite the inhibition.
   As updrafts cluster and shift north, a more sustained/sustained
   storm may evolve from these initial attempts. Diurnal heating/weak
   ascent may also support additional, isolated development around the
   dryline from east/northeastern OK into eastern KS. Poor handling of
   the situation by Hi-res guidance and nebulous forcing lends low
   confidence in additional convective development and the overall
   evolution. None the less, the strongly sheared and destabilizing air
   mass appears conditionally favorable for large to very large hail
   and possibly tornadoes late this afternoon into the evening. A
   greater threat will likely evolve overnight as the main trough
   ejects eastward. Trends will be monitored or a possible weather
   watch this afternoon but uncertainty is high.

   ..Lyons/Hart.. 04/04/2023

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...LZK...SGF...SHV...EAX...TSA...TOP...ICT...FWD...
   OUN...

   LAT...LON   32889550 32639719 32699788 33149825 33799804 34069798
               34409764 34819718 35429671 36009641 36699624 38009569
               38139522 38209434 38059368 37199279 36109280 34689342
               34099372 33479434 33179477 32889550 

 

Edited April 4, 2023 by Neoncyclone

[Central Illinois]

I bet that Supercell in MO already has significant hail with it 

[Iceresistance]

Just now, Central Illinois said:

I bet that Supercell in MO already has significant hail with it 

Tennis Balls right now

[Central Illinois]

2 minutes ago, Iceresistance said:

Tennis Balls right now

 

[Crowbar]

We're supposed to attend the 6th grade orientation for the incoming middle school students tomorrow at 6:00 at that school - wondering if that will get postponed.  

[Leenita]

16 minutes ago, Crowbar said:

We're supposed to attend the 6th grade orientation for the incoming middle school students tomorrow at 6:00 at that school - wondering if that will get postponed.  

In Olentangy as well and was wondering if they ever called school due to possible storms?

 

[snowlover2]

ILN latest thoughts. They do mention an enhanced tornado risk.

Quote

Quote

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Enhanced southwesterly low-level flow and strong moisture
advection will be the rule on Wednesday as deep surface low
pressure lifts from the Upper Midwest into southern Ontario.
CAMs show several potential rounds of convection developing
through the day while instability increases with time. It is
likely that any early showers/storms would be elevated...
however, by mid- to late-afternoon there will be several factors
in play that will bring a chance for strong to severe storms.

Surface-based instability in the 1000-2000J/kg range will
develop... though timing and location of the best instability
could depend on coverage of morning showers. Effective SRH
values may reach 200-300. Long, curved hodographs, particularly
in the early-mid afternoon, bring an enhanced tornado threat.
Despite these factors, the spatial extend of the best forcing
remains uncertain across the CAMs. Will certainly need to
continue to track conditions through aggressive mesoanalysis as
the system approaches tonight into Wednesday.

The front will slow Wednesday evening/night, but will
eventually push southeast of the region by late Wednesday night.
This will allow drying conditions from northwest to southeast
heading toward the end of the period.