Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

March 2 Severe Potential and Observations


Indystorm

Recommended Posts

  • Replies 494
  • Created
  • Last Reply

..OZARKS...LOWER MS/TN VALLEY AND AL TO OH VALLEY STATES

SCATTERED ELEVATED TSTMS IN CLUSTERS MAY BE CARRY OVER FROM LATE

DAY-1 PERIOD OVER PORTIONS OZARKS...LOWER OH VALLEY AND MID-SOUTH

REGIONS...WITH FAVORABLE CAPE ALOFT AND DEEP-LAYER SHEAR FOR HAIL.

SOME OF THIS ACTIVITY MAY PERSIST LONG ENOUGH TO BECOME SFC-BASED BY

MIDDAY AND EARLY AFTERNOON IN INCREASINGLY FAVORABLE ENVIRONMENT FOR

SVR. OTHER SCATTERED-NUMEROUS TSTMS SHOULD DEVELOP ALONG/AHEAD OF

COLD FRONT. TSTMS SHOULD BE FAST-MOVING...COVERING LONG SWATHS WITH

THEIR SVR THREATS OVER ANY GIVEN PERIOD OF TIME.

AIR MASS AHEAD OF SFC COLD FRONT AND IN WAKE OF MORNING CONVECTION

SHOULD DESTABILIZE FAVORABLY AMIDST STG LOW-LEVEL WAA/MOISTURE

TRANSPORT. INTENSE DEEP-LAYER SHEAR AND LOW-LEVEL HODOGRAPHS WILL

SPREAD OVER MUCH OF WARM SECTOR...ALONG WITH SFC DEW POINTS

INCREASING FROM MID 50S OVER OH TO MID 60S OVER PORTIONS MS/AL. IN

TANDEM WITH DIURNAL SFC HEATING...THIS SHOULD SUPPORT MLCAPE 250-500

J/KG OVER PORTIONS OH/INDIANA...TO 1500-2000 J/KG RANGE OVER

PORTIONS TN/KY...THEN DECREASING SOMEWHAT FARTHER S DUE TO

INFLUENCES OF STABLE LAYERS ALOFT. DESPITE UNCERTAINTIES REGARDING

EXTENT/COVERAGE OF VARIOUS CONVECTIVE MODES THIS FAR OUT...EXPECT

WEAK CINH...BROADLY FAVORABLE CAPE/SHEAR PARAMETER SPACE...AND

RELATIVELY DENSE COVERAGE OF CONVECTION LIKELY TO IMPINGE ON THAT

SETTING. AS SUCH...NUMEROUS SVR WIND EVENTS ARE POSSIBLE ALONG WITH

POTENTIAL FOR STG TORNADOES FROM EITHER SUPERCELLS OR QLCS-VORTEX

MECHANISMS. AT LEAST A FEW WIND EVENTS AOA 65 KT AND

LONG-TRACK/SIGNIFICANT TORNADOES ARE POSSIBLE. THEREFORE...

SIGNIFICANT-SVR AREA IS BEING INTRODUCED...DRIVING CATEGORICAL MDT

RISK WHERE OVERLAID WITH RELATIVELY DENSE 45% TOTAL-SVR PROBABILITY.

day2prob.gif

Link to comment
Share on other sites

Oh boy...

Also reading the text and comparing parameters between models, it appears they're favoring the GFS to a certain extent, especially regarding thermodynamic profiles.

There was about a 75-100 mile northward expansion of the probs on this outlook compared to the old day 3. I would not be surprised to see another bump northward if it appears that the NAM is on the right track.

Link to comment
Share on other sites

There was about a 75-100 mile northward expansion of the probs on this outlook compared to the old day 3. I would not be surprised to see another bump northward if it appears that the NAM is on the right track.

Gonna be a rough ride back to Seymour...

EDIT: I really need someone to do a time frame for me? When will these storms enter the western portion of Indiana???

Link to comment
Share on other sites

There was about a 75-100 mile northward expansion of the probs on this outlook compared to the old day 3. I would not be surprised to see another bump northward if it appears that the NAM is on the right track.

Yeah, I'm surprised they didn't move the slight risk into MI. The warm front looks like it will make it north of the border, and it looks like Detroit will be in the triple point. Yeah, it will probably be pretty marginal at best, but I could see a slight risk of an isolated tornado happening in MI, and damaging winds.

Link to comment
Share on other sites

All I have to say is wow at not only the setup but guys this is March 1st! Usually march outbreaks don't go much farther east and north than Southern Illinois up here so that fact the models are showing these kinds of numbers is staggering.

A few things to look at though is...

-With a system like this with storms firing along the front is how long they'll stay non-linear. If this is to be a big tornado outbreak and not just a damaging wind event these things will have to be on their own longer

-Morning convection plus CAPE only at about 500 j/kg tops in OH and IN worry me as well about how big this could be

If the ample moisture transport and super strong jet stream get going enough and we stay away from an event where things go linear immediately and the atmosphere is ripe enough, this could be an all-time event easy. The dynamics are there, the atmosphere has some questions still

Link to comment
Share on other sites

All I have to say is wow at not only the setup but guys this is March 1st! Usually march outbreaks don't go much farther east and north than Southern Illinois up here so that fact the models are showing these kinds of numbers is staggering.

A few things to look at though is...

-With a system like this with storms firing along the front is how long they'll stay non-linear. If this is to be a big tornado outbreak and not just a damaging wind event these things will have to be on their own longer

-Morning convection plus CAPE only at about 500 j/kg tops in OH and IN worry me as well about how big this could be

If the ample moisture transport and super strong jet stream get going enough and we stay away from an event where things go linear immediately and the atmosphere is ripe enough, this could be an all-time event easy. The dynamics are there, the atmosphere has some questions still

 

Southern IN/OH have as much as 2000+ J/kg SBCAPE per the NAM.

Link to comment
Share on other sites

Will be a big day for alot of OH VL. Mid MS. VL. We are targeting SE IL atm maybe a move to W/C TN if things destabilize enough. Worked tuesday night and did not get to spot chase but the power flashes several miles to south SE was impressive. I was talking to my mom calmly while she was in a closet with pillows and blankest when storm passed a few miles north of her. She is fine. Harrisburg is a wreck. Helped out a couple of people there yesterday morning, alot of shock.. Intense convergence in town. Its been a long time since we have seen that much convergence of a tornado in So.Il. Good and safe hunting to those that will be out.

Link to comment
Share on other sites

06 NAM has shifted Friday am 1500 convection/STP westward and se MO is now in play. That intense corridor moves ne during the day and by 00 UTC covers much of western OH/eastern IN. Gonna have to watch refinement as we get closer to the event wrt warm frontal progression and moisture advenction. And as Hoosier mentioned in his excellent analysis mesoscale day of processes will always come into consideration.That Dayton sounding gives me shivers.

Link to comment
Share on other sites

12z NAM has backed way off on the Significant Tornado Parameter for tomorrow afternoon/evening... except down near Cincinnati...

the 33 hr image is pretty amped up still just South some. However the RGEM came in stronger compared to the NAM.

Link to comment
Share on other sites

The GFS really lights up over Ohio tomorrow afternoon. At first I thought it was associated with the warm front, but looking at the 700mb RH fields and 850 temps it looks more like cold frontal activity. Doesn't look linear either, although the GFS low resolution makes that hard to determine.

Link to comment
Share on other sites

Will be a big day for alot of OH VL. Mid MS. VL. We are targeting SE IL atm maybe a move to W/C TN if things destabilize enough. Worked tuesday night and did not get to spot chase but the power flashes several miles to south SE was impressive. I was talking to my mom calmly while she was in a closet with pillows and blankest when storm passed a few miles north of her. She is fine. Harrisburg is a wreck. Helped out a couple of people there yesterday morning, alot of shock.. Intense convergence in town. Its been a long time since we have seen that much convergence of a tornado in So.Il. Good and safe hunting to those that will be out.

I can't ever remember a time where there has been such a media presence in southern Illinois.. not to wish ill will on anyone else, but I really really hope that this is a bust in SE IL tomorrow,

Link to comment
Share on other sites

NAM and GFS suggest the best threat will stay south of I-70 at least here in Indiana. If we can materialize some better instability up here, LAF isn't out of the game yet.

Gotta watch it closely. I look at the NAM/GFS 850 mb temps of 9C and the progged surface temps in the mid/upper 50's and seriously question that. Only way I could see it happening is if we are severely socked in with clouds.

Link to comment
Share on other sites

Gotta watch it closely. I look at the NAM/GFS 850 mb temps of 9C and the progged surface temps in the mid/upper 50's and seriously question that. Only way I could see it happening is if we are severely socked in with clouds.

Yes, I think temps are being very underdone especially with the strength of the LLJ roaring NEward across the area.

Link to comment
Share on other sites

Will be a big day for alot of OH VL. Mid MS. VL. We are targeting SE IL atm maybe a move to W/C TN if things destabilize enough. Worked tuesday night and did not get to spot chase but the power flashes several miles to south SE was impressive. I was talking to my mom calmly while she was in a closet with pillows and blankest when storm passed a few miles north of her. She is fine. Harrisburg is a wreck. Helped out a couple of people there yesterday morning, alot of shock.. Intense convergence in town. Its been a long time since we have seen that much convergence of a tornado in So.Il. Good and safe hunting to those that will be out.

Kevin - I have real questions on where storms initiate. Looking at the locally run St Louis WRF it is more bullish on morning convection - and further east, as well - well into KY/TN - then west. It forms a broken line of supercells across IL/MO/AR during the afternoon.

St Louis local run wrf - http://www.crh.noaa.gov/lsx/wrf/wrfdisplay.php

I see a lot of hesitatioon on the initi region. Seems like the soundings show more than sufficient CAPE over west KY and southeast IL - cap - even some loaded gun type soundings. But the trends on the models for 3 straight days has been further and further east with the low and the system - NAM has trended east for run after run it seems. Even if just a county or two at a time - over time it has added up.

Will be curious to see the SPC WRF shortly. Init will be key for my local counties.

Further east I am more worried - as is everyone. SPC probabilities look right.

I noticed the SREF moved the greatest tornado threat a bit further west in its morning run.

Just not sure on the race between the cold front/dry air/ and init.

Thoughts?

Link to comment
Share on other sites

http://www.accuweather.com/en/weather-news/friday-tornado-setup-similar-t/62259?fb_comment_id=fbc_10150599773478492_21212465_10150599920023492#f2d9b3d4f8ab6ec

And they're at it again...

Envoke images of 1974, then go on to describe conditions that occur in basically every tornado event (or cold frontal passage for that matter). We already struggle with public perception and reaction to warnings statements. Hyperbolic statements such as this don't help the cause.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...