Spring/Summer 2016 Severe Weather Thread

[Geos]

I think most of the severe weather will be south of where I am. Onshore winds, and clouds look to dominate the day. The severe weather will want to pop where the high dewpoints meet areas where the sun is/was out.

 

NAM only gets it this warm tomorrow with rain most of the day.

[Geos]

This is bad news...

 

[jaster220]

This is bad news...

 

 

Not a severe wx nut and don't ask me which way is up on a hodograph (LOL) but when I see those who know their stuff posting things like "hodo's anywhere near the WF are insane and true wx porn" it makes me take notice. Torcon of 5-ish over my way at night is a bit concerning as well. Especially since my oldie-but-goodie NOAA radio gave it up last summer. Battery power was helpful and comforting when the power goes. My kid with the smart phone is on holiday as they say in Europe so no help there. I don't get alerts like some/most of you

[Hawkeye]

I've been following the latest 4k nam, hrrr, and hrrrx runs all day.  The 4k nam and hrrrx are similar in showing most of the storms north and east of my area.  The hrrr, on the other hand, drives a huge mcs down through Iowa with very little to the north and east.

[Tom]

18z NAM cut back on qpf but still showing several clusters of storms throughout the day for N IL...

 

http://www.tropicaltidbits.com/analysis/models/nam4km/2016062118/nam4km_apcpn_ncus_13.png

 

 

These type of NW Flow set-ups love to blossom where the most heat is located and occasionally drift south.  Like you said Hawkeye, HRRR is farther south than the high rez NAM. 

[Geos]

18z NAM cut back on qpf but still showing several clusters of storms throughout the day for N IL...

 

 

 

These type of NW Flow set-ups love to blossom where the most heat is located and occasionally drift south.  Like you said Hawkeye, HRRR is farther south than the high rez NAM. 

 

I think you're in a better spot to see the severe weather. Up here, probably more of a heavy rain threat. Ground is pretty dry, so there could be some flash flooding.

[Tom]

LOT continues with strong wording with this potent system...

 

http://www.weather.gov/images/lot/WxStory/FileL.png?rand=72524

 

 

 

 

The severe weather event is currently forecast to unfold during the
mid-late afternoon through the evening Wednesday. However...as is
typical with thunderstorm forecasting this far out...the main
challenge forecasting this severe threat later in the
afternoon/evening will be with regards to how much recovery occurs
in the afternoon...along with the placement and behavior of any
residual mesoscale boundaries from the expected morning convective
activity. There are some minor differences in the placement of the
warm frontal boundary...and track of the surface low over the area
Wednesday evening. However...in spite of these slight
differences...there is a general corridor across northern Illinois
into northwestern Indiana...where hires guidance is suggesting that
strong backed surface flow will set up later in the afternoon...in
the vicinity of a surface warm frontal boundary. With strong veering
flow expected within the lowest 1 km...very impressive low-level
shear/helicity...is forecast. Because of this, there is a real
threat of strong tornados over northern Illinois Late Wednesday
afternoon/evening. The main challenge at this range is the exact
placement of this surface boundary as convection develops.

Given that recovery is expected following the morning
storms...storms are expected to redevelop...possibly over or near
north central/northwestern Illinois (near the triple point) by mid
afternoon. With deep layer shear likely to support rotating
updrafts...super cells...with all severe hazards...will likely be
the initial storm mode. With time...expect the storms to begin to
grow upscale into a southeastward moving MCS with Strong damaging
winds...and possible embedded tornados over the area into Wednesday
evening.

In additional to the real significant severe risk, there is also a
threat of flash flooding. Although the storms are expected to move
at a good clip, I have two main concerns that could point to a flash
flood risk: 1.) The possibility of some training storms with an east-
southeastward movement nearly parallel to the surface boundary, and
2.) Very efficient rainfall processes with Pwats expected to be at
or above 2". Because of this, the storms could drop rainfall amounts
of 2+ inches within an hour. This could cause flooding
issues...especially in urban areas. In spite of the fact that there
looks to be some dry time early Wednesday afternoon, I have opted to
run this watch from Wednesday morning through Wednesday evening to
capture both potential periods of heavy rain.

[Tom]

Flood watches hoisted in IA/N IL...I know this is off subject, but it looks an advisory lay-out which we would typically see from a Clipper in the winter!  LOL, always thinking about the cold season....

 

http://forecast.weather.gov/wwamap/png/US.png

[Geos]

Flood watches hoisted in IA/N IL...I know this is off subject, but it looks an advisory lay-out which we would typically see from a Clipper in the winter!  LOL, always thinking about the cold season....

 

 

 

Lol, that's what my first impression was too.

 

[hlcater]

2-4" of rain or 2-4" of snow?????

[james1976]

http://www.wpc.ncep.noaa.gov/metwatch/images/mcd0370.gif
​Pretty serious potential for training storms tonight.
 

[Geos]

Update from LOT
 

 

AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
857 PM CDT TUE JUN 21 2016  
   
UPDATE  
 
855 PM CDT  
 
CHALLENGING FORECAST NEXT 24 HOURS FROUGHT WITH UNCERTAINTY.  
SURFACE ANALYSIS THIS EVENING HAS A WARM FRONT STRETCHING NW TO SE  
ACROSS THE REGION, LOCATED ACROSS WC TO SE IL. TO THE NORTH OF THE  
BOUNDARY IN OUR CWA, VERY DRY AIR MASS IN PLACE WHILE SEASONABLY  
MOIST AIR MASS NEAR/SOUTH OF THE BOUNDARY. VERY MOIST AIR MASS  
RESIDES NEAR THE BOUNDARY WHERE MID 70 DEWPOINTS ARE POOLING.  
 
HAVE ALREADY SEEN SOME WIDELY SCATTERED STORMS DEVELOP IN THE WAA  
REGIME JUST TO THE NORTH OF THIS BOUNDARY OVER CENTRAL IA AND  
WOULD EXPECT COVERAGE AND INTENSITY OF STORMS TO INCREASE TONIGHT  
AS 40KT+ LLJ RESULTS IN STRONG THETA-E ADVECTION. GIVEN THE  
ORIENTATION OF THE WARM FRONT/INSTABILITY AXIS AND STEERING FLOW  
LARGELY FROM THE NW, WOULD EXPECT MAJORITY OF THIS CONVECTION TO  
MOVE SE INTO CENTRAL IL TONIGHT AND LARGELY MISS A GOOD MAJORITY  
OF OUR CWA. SOME OF THE LIGHTER MORE STRATIFORM PRECIP ON THE  
NORTHERN FLANK OF THIS CONVECTION WILL LIKELY SPREAD INTO MAINLY  
OUR WESTERN AND SOUTHERN CWA AFTER MIDNIGHT.  
 
MANY MODELS SUGGEST THAT THIS WAA DRIVEN ACTIVITY COULD FESTER  
WELL INTO THE AFTERNOON HOURS WEDNESDAY ONLY GRADUALLY SPREADING  
NORTH. THE LAST FEW RUNS OF THE HRRRX DEVELOP A HEALTHY COLD POOL  
THAT PUSHES THE EFFECTIVE OUTFLOW AUGMENTED FRONT FAR TO THE  
SOUTH...SOUTH OF I-70 EVEN BY MID-LATE WEDNESDAY MORNING. NOT  
CONFIDENT THAT FRONT WILL BE THIS FAR SOUTH, BUT FIGURE WITH  
CLOUDS AND PROBABLY SHOWERS AND ISOLD STORMS CONTINUING INTO THE  
AFTERNOON WITH A WIND OFF THE LAKE THAT TEMPS WILL BE COLDER  
TOMORROW THAN WE HAD GOING. HAVE KNOCKED TEMPS BACK SEVERAL  
DEGREES OVER ABOUT THE NE HALF OF OUR CWA AND EVEN THE MID-UPPER  
70S IN THE GRIDS NOW MAY END UP BEING TOO WARM (ESPECIALLY NEAR  
THE LAKE).  
 
IT IS A TIME OF YEAR THAT WARM FRONTS CAN JUMP NORTH QUICKLY, AND  
THAT IS CERTAINLY POSSIBLE, ESPECIALLY GIVEN FAIRLY STRONG  
SHORTWAVE AND ASSOCIATED SFC LOW FOR THIS TIME OF YEAR. IT IS  
LOOKING LIKE THE MORE SUBSTANTIAL SEVERE THREAT COULD END UP  
NEEDING TO BE EVENTUALLY SHIFTED SOUTH IF WAA DRIVEN CONVECTION  
OVERNIGHT INTO WED MORNING IS AS EXTENSIVE AS GUIDANCE SUGGESTS.  
 
IZZI 

 

[Tom]

Chitown still out looked in the Moderate category as well as IN/OH...TORCON was raised to a 6 for Chicago

 

 

 

 

 

Here is the Tornado Threat which suggests N IL in the prime spot...

 

 

 

 

Some very heavy rainfall in IA last night.  Close to Hawkeye and James region.

 

[Tom]

According to satellite imagery, clouds are beginning to clear in SW WI/N IA and S MN.  The atmosphere is going to destabilize if this trend continues which should ultimately produce these powerhouse storms.

 

 

Latest RPM model blossoms storms in N IL just after 6pm.....

[Geos]

So far today clouds and sprinkles. Sun will have to come out to destabilize the atmosphere. I think the most significant severe weather will be west of the lake somewhat.

[Hawkeye]

3.97" is what I ended up with.  The first two inches came in an hour, the next two several hours.  A little hail and more lightning/thunder would've been nice, but I can't complain.  It was a fun event to follow.

[Geos]

New info.

 

 

[Geos]

Winds are stating to blow inland from Lake County on northward. Might be enough to keep the most severe storms west.

[Tom]

This air mass feels so juicy after some lighter rains.  Intermittent sunshine is peaking through the clouds.  Looks like its trying to clear up in S WI right now.

[Madtown]

Full sun up to 82 here. Thinking I'll be on the far northern fringe of everything if anything.

[Geos]

Clouds have been really persistent around here today. Warm front is a good 100 miles to the southwest currently.

 

 

At 72/65 currently. 

[Madtown]

Thick clouds are back...hope we get some rain out of this. Grass is starting to fry!

[Tom]

Some showers starting to fire in E IA right now...right on schedule according to high rez models and RPM model...let's see if they start to blossom as the CAP breaks.

 

http://climate.cod.edu/data/nexrad/DVN/N0Q/DVN.N0Q.20160622.2210.gif

[Jaycee]

Maybe you guys will hear the most unnecessary and scary tornado sirens tonight!

 

https://youtu.be/LnkMSmLc6mM

 

Stay safe you guys, these hirez models crush your area.

[Tom]

Maybe you guys will hear the most unnecessary and scary tornado sirens tonight!

 

 

Stay safe you guys, these hirez models crush your area.

Sounds more like a warning for an alien invasion! Haha...Independence Day thriller hits theatres Friday!

[Madtown]

Looks like a bust up this way.

[Geos]

Getting missed largely so far.

 

Might have to keep on watering if convection doesn't start filling in.

[Geos]

Hook NNW of Princeton

 

[Geos]

Confirmed TOG

 

SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 721 PM CDT WED JUN 22 2016 ILC103-230045- /O.CON.KLOT.TO.W.0007.000000T0000Z-160623T0045Z/ LEE IL- 721 PM CDT WED JUN 22 2016 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 745 PM CDT FOR SOUTHEASTERN LEE COUNTY... AT 721 PM CDT...A CONFIRMED TORNADO WAS LOCATED 8 MILES EAST OF AMBOY...OR 10 MILES NORTH OF MENDOTA...MOVING EAST AT 25 MPH. HAZARD...DAMAGING TORNADO. SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO ROOFS...WINDOWS...AND VEHICLES WILL OCCUR. TREE DAMAGE IS LIKELY. LOCATIONS IMPACTED INCLUDE... COMPTON AND WEST BROOKLYN. PRECAUTIONARY/PREPAREDNESS ACTIONS... HEAVY RAINFALL MAY HIDE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR THE TORNADO. TAKE COVER NOW.

 

[Tom]

@ Jaster, I think you are finally poised to get some beneficial rains out of this system!  Is it raining yet out by you?

[Geos]

Huge tornado near Earlsville right now.

 

[Tom]

I'm getting pounded by torrential rains...its like a tropical monsoon out there...as I write this, a brand new Severe Thunderstorm Warning issued....

 

 

 

Severe Thunderstorm WarningSEVERE THUNDERSTORM WARNING
ILC031-043-230215-
/O.NEW.KLOT.SV.W.0031.160623T0111Z-160623T0215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
811 PM CDT WED JUN 22 2016

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
DUPAGE COUNTY IN NORTHEASTERN ILLINOIS...
CENTRAL COOK COUNTY IN NORTHEASTERN ILLINOIS...

* UNTIL 915 PM CDT

* AT 811 PM CDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
EXTENDING FROM SCHAUMBURG TO HANOVER PARK TO DUPAGE AIRPORT...
MOVING SOUTHEAST AT 30 MPH.

HAZARD...60 MPH WIND GUSTS AND PENNY SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES.

* LOCATIONS IMPACTED INCLUDE...
CHICAGO...CICERO...SCHAUMBURG...DES PLAINES...BERWYN...MOUNT PROSPECT...
WHEATON...HOFFMAN ESTATES...OAK PARK...DOWNERS GROVE...ELMHURST...
LOMBARD...CAROL STREAM...PARK RIDGE...ADDISON...ST. CHARLES...GLEN
ELLYN...WEST CHICAGO...WESTMONT AND MAYWOOD.

PEOPLE ATTENDING BLOCK TO BLOCK PARTY SHOULD SEEK SAFE SHELTER
IMMEDIATELY!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH A TORNADO IS NOT
IMMEDIATELY LIKELY...IF ONE IS SPOTTED...ACT QUICKLY AND MOVE TO A
PLACE OF SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR
SMALL INTERIOR ROOM.

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

[Geos]

Glad someone's getting some good rain. The amount of rain that has fallen here isn't going to do much.

 

Was watching the live stream of the tornado, until the feed cut out.

https://www.periscope.tv/Jeff_Piotrowski/1gqxvMdWLYOJB

 

Best in IE.

[Geos]

Another good feed

[Geos]

More action in the southern suburbs. Might be something trying to spin up near Dolton.

 

[Geos]

Both Pontiac and Seneca were hit with tornadoes this evening.

[Tom]

Pontiac, IL was hit hard last night with a cone shaped Tornado...I received 1.61" of rain in a 30-40 min period.  It was raining buckets, literally...

 

 

 

 

[jaster220]

@ Jaster, I think you are finally poised to get some beneficial rains out of this system!  Is it raining yet out by you?

 

Thanks Tom. It started closer to 10pm (EDT) and was NOT SEVERE in any way shape or form. Not even so much as a loud clap of thunder, just a few distant rumbles were heard. Didn't see/hear anything close to +RN either. Near as I can estimate .4-.5" fell in Marshall. Not a drought buster, but beats another whiff any day - lolz   GRR's map is ridiculously overdone, at least around here showing 1-2". Yeah, right GRR 

[Tom]

A couple more pics from the (7) confirmed Tornado's yesterday...the Pontiac one was the strongest at an EF-2 up to 125mph winds.

 

 

 

A year ago to the date yesterday, Coal City, IL was demolished with a huge Tornado outbreak.  This year, thankfully, they were spared.

[OKwx2k4]

Many thoughts and prayers went up for you guys up there yesterday. Thank goodness things weren't worse.