2016 Short/Medium Term Severe Thread

[Jim Martin]

It would not shock me if this storm goes on to be a long track supercell...

[Jim Martin]

Terre Haute, Indiana could be next...

[Indystorm]

The Terre Haute storm could intensify and produce.  I am more concerned now with the actual tor on the ground in the Danville area.

[Indystorm]

Thank goodness lapse rates aren't any stronger than they currently are.

[Jackstraw]

12 minutes ago, Indystorm said:

Thank goodness lapse rates aren't any stronger than they currently are.

I agree, any kind of decent lapse rates and these things could explode but what's lacking in lapse rates is being made up by low level inflow.  It's really evident on radar.  3 decent couplets on the Danville line getting ready to move just south of LAF.  What a freaky late summer string of events.

[HillsdaleMIWeather]

Latest SPC outlook calling for initiation in Michigan in a few hours, says a Tornado or two possible.

[Indystorm]

Strongest cluster of storms at 9;50 p.m. between Lafayette and Crawfordsville.  Don't think we have had any confirmed touchdowns here in IN like they have had in IL.

[Chambana]

Major damage in Champaign County, South of Homer. My brother and his wife were on their way home and got a picture of the tornado on ground, they live in Sidney. 

 

Survey crews will be on scene tomorrow to assess damage and determine strength. CMI picked up 2.4" of rain in 4 hours. 

[Chambana]

It's been an incredibly wet pattern as of late, really dating back to the beginning of summer, not just our sub, but even out west in the plains, upper MW, Deep South with the unnamed low.

 

STL getting dumped on right now, RadarScope showing torrential rainfall. 

[Chambana]

Looks like 3-5" totals popping in STL

[Chambana]

Got some nice images from the Homer tornado. The first picture is of the tornado, my brothers wife snapped it looking out there back door looking SE.

Second photo is an RV completely crushed and thrown like a rag doll. I'm thinking EF-3 possibly. 

 

[Chinook]

severe thunderstorm watch likely for Ohio, Kentucky

 

Quote

   CONCERNING...SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY 


   PROBABILITY OF WATCH ISSUANCE...80 PERCENT

   SUMMARY...THE RISK FOR SVR TSTMS CAPABLE OF PRODUCING ISOLATED TO
   WIDELY SCATTERED DMGG WIND GUSTS IS INCREASING WITHIN AN EXTENSIVE
   CORRIDOR FROM PORTIONS OF KY NEWD TO PORTIONS OF SWRN NY. 

 

[snowlover2]

New watch up.

 

Quote

URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 473
   NWS STORM PREDICTION CENTER NORMAN OK
   225 PM EDT SAT SEP 10 2016

   THE NWS STORM PREDICTION CENTER HAS ISSUED A

   * SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
     SOUTHEAST INDIANA
     CENTRAL KENTUCKY
     SOUTHWEST AND CENTRAL OHIO

   * EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 225 PM UNTIL
     900 PM EDT.

   * PRIMARY THREATS INCLUDE...
     SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

   SUMMARY...A LINE OF STORMS ALONG A COLD FRONT SHOULD SWEEP EASTWARD
   THIS AFTERNOON. STRONG TO ISOLATED SEVERE WIND GUSTS ARE
   EXPECTED...PRODUCING SCATTERED DAMAGING WINDS.

   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 85
   STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF
   COLUMBUS OHIO TO 25 MILES SOUTH SOUTHWEST OF BOWLING GREEN
   KENTUCKY.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
   ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
   DO PRODUCE TORNADOES.

 

[Hoosier]

6 hours ago, Chambana said:

Got some nice images from the Homer tornado. The first picture is of the tornado, my brothers wife snapped it looking out there back door looking SE.

Second photo is an RV completely crushed and thrown like a rag doll. I'm thinking EF-3 possibly. 

 

The picture posted on the previous page was pretty impressive.  I would certainly guess this was an EF2 tornado at minimum.

[Chicago Storm]

Summer 2016, season of the surprise tornado events.

[Hoosier]

So far, one EF2 and one EF0 confirmed by ILX.  They are still surveying.

[janetjanet998]

19 hours ago, Hoosier said:

So far, one EF2 and one EF0 confirmed by ILX.  They are still surveying.

2 more an EF0 and EF1

 

but both weak EF0's were discovered from corn crop damage , if it were May those would not of been found or counted

 

on a side note, back in the early 1990's when looking at IL tornado history,  I always wondered why Sangamon county IL had such a high number and what happened back in AUG of 197X(forgot the year) in that area with many tornado reports in one day

 

update: Aug 6th 1977 was the date 17 tornadoes

 

turns out i found out years later DR Fujita did a study on a severe weather event and documented many small weak tornadoes(while documenting stronger ones) which i assume he found from crop damage

[cyclone77]

Relatively interesting local setup tomorrow afternoon/evening.  Southern WI down into eastern IA/far northwest IL has a shot at some severe.  Looks like a pretty impressive band of cape will build out ahead of the approaching cold front.  Some models show over 5000j/kg over southern IA, and that tapers down towards 3000j/kg up towards Wiscaaaansin.  Excellent moisture/surface convergence combined with the instability should mean we should have no problem blowing up convection later in the afternoon.  Low-level shear looks pretty good, but craps out above 850.  Storms may have a tendency to unzip southwestward along the front building towards the best instability further southwest.  For that reason I think the best shot at the strongest convection could end up on the Iowa side, somewhere in the vicinity of Cedar Rapids.  There's enough low-level shear to present a decent shot for a few tornadoes with the dominant cells.  May have to head up towards Vinton and see if one of these puppies can puke out a quick tor before sunset, which is now pretty early- around 7pm.

 

12z 4km NAM forecast sounding for just east of Cedar Rapids at 00z tomorrow.

[hawkeye_wx]

For Monday afternoon/evening, DVN is thinking north and east of the Quad Cities.

[hlcater]

Haven't even looked into it, but based on the SPC outlook, CP looks too far NW. Will have to later.

[cyclone77]

7 hours ago, hawkeye_wx said:

For Monday afternoon/evening, DVN is thinking north and east of the Quad Cities.

North yes.  Northeast naso much.  Convection looks likely to unzip as far west as the I-35 corridor eventually.

 

4 hours ago, NWLinnCountyIA said:

Haven't even looked into it, but based on the SPC outlook, CP looks too far NW. Will have to later.

They've been cutting the nuts off the western extent of the setup too much up to this point.  Looks like you guys are sitting pretty close to where the best action will be from this setup.  The 20 corridor between Dubuque and Waterloo may end up being the best location for meaningful severe, as the 00z guidance slowed the progression of the front even more compared to previous runs.  

 

EDIT:  New day 1 looks considerably better compared to the previous outlooks.

[andyhb]

As far as tornado potential for tomorrow, I'm noticing that the overall ESRH values are quite impressive, but the 0-1 km SRH is fairly anemic because of the weak flow at 850 mb and below, especially around 21z. That might lead to a "wall cloud outbreak" vs. supercells becoming tornadic should said storm mode dominate.

[Hoosier]

10 hours ago, andyhb said:

As far as tornado potential for tomorrow, I'm noticing that the overall ESRH values are quite impressive, but the 0-1 km SRH is fairly anemic because of the weak flow at 850 mb and below, especially around 21z. That might lead to a "wall cloud outbreak" vs. supercells becoming tornadic should said storm mode dominate.

The low level flow is fairly weak but there's a lot of turning in the lowest km.  I see this as a setup that could really go either way, from little/nothing tornadic to a localized outbreak.

[cyclone77]

Weak surface low over central Iowa is keeping surface winds over eastern Iowa fairly backed.  Seeing some 15-20kt wind gusts as well.  Wish the flow immediately above that was better, but hopefully the 25-30kts at 850 is enough.  The shear between 850 and 300 is pretty impressive.  Should get those storms spinning pretty nicely in the mid-layer.  If the storms can dig in and deviate even further to the right that could really help things out in the low-levels.  I see SPC recently added hatched hail probs for eastern Iowa.  

 

Probably gonna head out toward the Cedar Rapids/Dubquque area in a little while.  

[hlcater]

80% tor watch likely

 

EDIT: Added text

Quote

  CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 

   VALID 191902Z - 192000Z

   PROBABILITY OF WATCH ISSUANCE...80 PERCENT

   SUMMARY...THUNDERSTORMS WILL LIKELY INITIATE DURING THE 19-22Z
   PERIOD ACROSS SRN WI INTO CNTRL AND ERN IA.  SUPERCELLS WILL BE
   CAPABLE OF LARGE TO VERY LARGE HAIL AND A RISK FOR A SUPERCELL
   TORNADO.  A TORNADO WATCH IS LIKELY FOR PORTIONS OF SRN INTO ERN IA
   AND ADJACENT PORTIONS OF IA/IL.

   DISCUSSION...18Z SUBJECTIVE SURFACE MESOANALYSIS PLACES A 1012-MB
   LOW 30 MI NW DSM WITH A FRONT EXTENDING NEWD FROM THE LOW INTO SRN
   WI AND NEAR THE DOOR PENINSULA.  STORMS WILL LIKELY INITIATE NEAR
   THE BOUNDARY AND THE LATEST RADAR/LIGHTNING DATA AT 1855Z SUGGESTS
   INITIATION IS UNDERWAY IN SRN AND SERN WI.  THE STRONGER UPDRAFTS
   MAY ACQUIRE ROTATION AND AN ISOLD HAIL/WIND RISK COULD DEVELOP WITH
   THIS EARLY AFTERNOON ACTIVITY OVER SERN WI.  

   FARTHER W OVER CNTRL AND E-CNTRL IA...CONVECTIVE INHIBITION IS
   GRADUALLY ERODING AS TEMPS WARM THROUGH THE 80S AND DEWPOINTS RISE
   INTO THE LOWER 70S.  ONCE THE CAP IS BREACHED --MOST LIKELY DURING
   THE 20-22Z PERIOD PER LATEST STORM-SCALE GUIDANCE-- STRONG BUOYANCY
   /1500-2500 J PER KG MLCAPE/ WILL RESULT IN FAIRLY RAPID STORM
   DEVELOPMENT.  THE LONG AND ENLARGING HODOGRAPH WITH TIME WILL
   STRONGLY FAVOR A SUPERCELL MODE...DESPITE SOME EVENTUAL CLUSTERING
   OF STORMS.  LARGE TO VERY LARGE HAIL WILL BE POSSIBLE WITH THE
   STRONGER STORMS AND THE RISK FOR A SUPERCELL TORNADO MAY DEVELOP
   DURING THE LATE AFTERNOON/EARLY EVENING TIMEFRAME.

   ..SMITH/THOMPSON.. 09/19/2016

 

[janetjanet998]

REA FORECAST DISCUSSION   NATIONAL WEATHER SERVICE QUAD CITIES IA IL   222 PM CDT MON SEP 19 2016    

 

  SYNOPSIS     ISSUED AT 208 PM CDT MON SEP 19 2016    

 

A PERFECTLY DIURNALLY TIMED EVENT IS GETTING READY TO IMPACT THE   CWA WITH THE THREAT OF SUPERCELL THUNDERSTORMS. THIS EVENT, THOUGH   NOT OBVIOUSLY HIGH END, HAS SOME SIMILARITY TO THE IOWA CITY   TORNADO EVENT, WHICH OCCURRED APRIL 13, 2006. A SURFACE LOW OVER   CENTRAL IOWA WILL SLIDE EAST ALONG THE APPROACHING COLD FRONT LATE   THIS AFTERNOON, LOCALLY ENHANCING THE LOW LEVEL SHEAR TO ALLOW FOR  TORNADOES WITH SUPERCELLS ROUGHLY ALONG INTERSTATE 80 TO HIGHWAY   30 IN IOWA THIS AFTERNOON THROUGH EARLY EVENING. LARGE HAIL AND   MARGINALLY SEVERE WINDS ARE ALSO POSSIBLE IN ANY STORM TODAY,   GIVEN DEEP LAYER SHEAR OF 40 TO 50 KTS AND CAPE OF 2000+.   ERVIN  

[Chicago Storm]

Main show will be the hailers in SW. WI.

[janetjanet998]

TOR watch for eastern IA but the first cell that developed just went poof

[Indystorm]

LCL's are fairly high in eastern IA.  We'll have to see how that impacts this event this evening. I wonder about the Bears game in Chicago this evening with that line barrelling se from WI, yet dews are fairly low in ne IL.

[hawkeye_wx]

DVN just stated that their area is capped.