July 11-14 Severe Weather Event

[A-L-E-K]

With a bullseye of 24", I'd say so.  What is it with that model and qpf bombs?

 

overdone?

[Geos]

Cyclone will need a boat if the 12z 4km NAM is even half way right!

[ClicheVortex2014]

overdone?

There's nothing on the run that would even suggest >2" of rain in that area, nonetheless 24.

[Hoosier]

Huge area of 80+ degree dewpoints on the 84 hour NAM.  Normally it happens in smaller pockets so I tend to think it's overdone on the coverage area, but damn.

 

 

[A-L-E-K]

12z GFS with a major wet signal 

[ClicheVortex2014]

Huge area of 80+ degree dewpoints on the 84 hour NAM.  Normally it happens in smaller pockets so I tend to think it's overdone on the coverage area, but damn.

 

 

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9300 CAPE...

 

 

 

12z GFS with a major wet signal 

Excellent pattern all throughout the run.

[Hoosier]

9300 CAPE...

 

 

 

Excellent pattern all throughout the run.

 

 

lol was just going to post a sounding.  That's what happens when you have dews near 85 and steep lapse rates aloft.

[Hoosier]

As far as what day has higher severe potential in the region, I'd lean more toward Monday than Sunday and I could easily see an ENH or moderate risk once things become more clear.  Monday should have a stronger surface low/wind fields in the area. 

[IWXwx]

Bets on which NAM run spits out the magical 10,000.

[ClicheVortex2014]

Dr. Forbes is mentioning the possibility of a derecho on Sunday and Monday.

 

SUNDAY
Isolated to scattered severe thunderstorms along and north of a 
warm/stationary front in east ND, north, central and southeast MN,
WI, western upper and lower MI, IN, west and central KY, IL, east
IA. TORCON - 2 to 3. These storms may occur in clusters (MCSs), continuing overnight. If individual storms are able to fire in
east IA by evening, then TORCON could be higher, but it appears 
that storms may wait there until an evening/overnight MCS. This
pattern could support a derecho (bow echo giving long-lived severe
thunderstorm wind event)

 

 

MONDAY
Severe thunderstorms - probably in one or more clusters (MCSs and possibly derechos/widespread thunderstorm windstorms) - running southeast along and just east of a warm/stationary front in WI, MI, north and east-central IL, north, central, and southeast IN, OH, west PA, WV, western VA, northeast TN, east half KY. TORCON - 2 to 3. There is a chance of a higher value if storms were able to build farther west into central and south IL, but that area may remain capped (warm layer aloft) and storm-free. Storms may continue into the night.

 

 

 

 

Bets on which NAM run spits out the magical 10,000.

 

I'll play it safe and say 06z or 18z.

[Thundersnow12]

Will be interesting to watch Monday as the NAM has the threat further south as it pushes the frontal boundary well into central IL but the 12z GFS would favor further north up here. 

[A-L-E-K]

you know south is the way to go

[Powerball]

Huge area of 80+ degree dewpoints on the 84 hour NAM.  Normally it happens in smaller pockets so I tend to think it's overdone on the coverage area, but damn.

 

 

Untitled.png

 

lol at -17 LIs...

[ClicheVortex2014]

Updated IND

 

UPPER RIDGE CENTERED OVER THE CENTRAL GULF COAST THIS AFTERNOON WILL
RETROGRADE INTO THE HIGH PLAINS BY MONDAY AND LEAVE THE REGION ON
THE PERIPHERY OF THE RIDGE. SEVERAL PIECES OF ENERGY ALOFT WILL
EJECT OUT OF THE DEEP TROUGH ALONG THE PACIFIC COAST...RIDING UP AND
OVER THE RIDGE BEFORE DIVING INTO THE OHIO VALLEY AND GREAT LAKES.
SOUTHWARD PROGRESSION OF A STRONG UPPER LOW NEAR JAMES BAY EARLY
NEXT WEEK WILL FURTHER SERVE TO LOWER THE HEIGHTS ALOFT OVER THE
REGION...ULTIMATELY PLACING CENTRAL INDIANA IN A FAVORED LOCATION
FOR BEING IMPACTED BY SEVERAL ROUNDS OF CONVECTION. WITH THE FRONT
BACK FURTHER NORTH AS WELL...COULD BE QUITE AN ACTIVE PERIOD LATE
WEEKEND INTO EARLY NEXT WEEK AND BEYOND.

MOST OF SATURDAY WILL BE QUIET AND MORE TYPICAL OF A SUMMER DAY AS
THE FRONT BEGINS TO LIFT BACK NORTH INTO THE FORECAST AREA. COULD
SEE CLOUD DEBRIS FROM UPSTREAM CONVECTION DURING THE COURSE OF THE
DAY BUT A DRIER AND MORE STABLE AIRMASS SHOULD KEEP MOST AREAS DRY.
WILL MAINTAIN A LOW POP OVER WESTERN COUNTIES DURING THE AFTERNOON
IN CLOSER PROXIMITY TO THE FRONT.

THE FRONT WILL LIFT NORTH THROUGH THE REGION SATURDAY NIGHT USHERING
IN A MUCH MORE HUMID AIRMASS AS IT PASSES. MODEL SUITE STILL
PROVIDING HINTS AT RENEWED CONVECTIVE DEVELOPMENT ALONG THE BOUNDARY
OVER THE UPPER MIDWEST SATURDAY EVENING...LIKELY MIGRATING INTO THE
REGION LATE SATURDAY NIGHT AND EARLY SUNDAY. WITH BULK OF THE
INSTABILITY ELEVATED ALONG THE FRONT...NOT REALLY IMPRESSED WITH
SEVERE POTENTIAL WITH THESE STORMS. COULD SEE SOME GUSTY WINDS BUT
ULTIMATELY AND UNFORTUNATELY...PRIMARY IMPACT FROM ANY OVERNIGHT
CONVECTION WILL BE ADDITIONAL HEAVY RAINFALL. THESE STORMS MAY
LINGER OVER PARTS OF THE FORECAST AREA THROUGH THE FIRST HALF OF
SUNDAY BEFORE BECOMING MORE SCATTERED.

SEVERE THREAT LIKELY TO RAMP UP FOR THE REST OF THE SHORT TERM AS
THE FRONT SETTLES OVER THE GREAT LAKES AND SEVERAL WAVES ALOFT
TRAVERSE THROUGH THE REGION. MODELS DIFFER TO SOME DEGREE ON TIMING
OF THE INDIVIDUAL WAVES AND AS HAS BEEN DISCUSSED...MESOSCALE
FEATURES SUCH AS OUTFLOW BOUNDARIES WILL BE FACTORS IN ADDITIONAL
DEVELOPMENT. COULD SEE ANOTHER STORM COMPLEX MIGRATE INTO THE REGION
FROM THE NORTHWEST SUNDAY NIGHT WITH ANOTHER ROUND OF HEAVY RAINFALL
AND STRONG STORMS.

THE WAVE ALOFT SET TO ARRIVE INTO THE GREAT LAKES MONDAY/MONDAY
NIGHT IS THE STRONGEST OF THE SHORT TERM AND AT FIRST GLANCE...
PRESENTS OMINOUS SIGNALS THAT WOULD SUPPORT SEVERE WEATHER. BULK OF
THE MODEL GUIDANCE IS INDICATING STRONG INSTABILITY OVER CENTRAL
INDIANA ON MONDAY TO THE TUNE OF 3000-5000 J/KG AND THIS SEEMS
REASONABLE CONSIDERING DEWPOINT AIR APPROACHING 75 DEGREES. WITH A
NOTED LOW LEVEL JET AND POTENTIAL FOR GREATER IMPACTS FROM A
STRONGER JET ALOFT ACCOMPANYING THE WAVE...ALL THE FACTORS ARE
PRESENT FOR ROBUST CONVECTIVE DEVELOPMENT LIKELY IN THE FORM OF A
SQUALL LINE OR MCS. DAMAGING WINDS AND VERY HEAVY RAINFALL WOULD
BE THE MAIN THREATS AND WILL HIGHLIGHT IN THE HWO. VERY LIKELY
THAT ADDITIONAL FLASH FLOOD HEADLINES WILL EVENTUALLY BE NEEDED
SHOULD ALL THIS COME TO FRUITION.

 

 

[Hoosier]

lol at -17 LIs...

 

 

Reminiscent of 7/13/1995 in IL, although there was too much capping to get anything going.

[TimChgo9]

Looks like the heaviest activity  just may wind up south of here.  Probably going to be I-80 and south for the heaviest rain on Sunday.  

 

From LOT. 

 

ON SATURDAY...SURFACE WARM FRONT WILL ADVANCE NORTHEAST ACROSS THE
MISSISSIPPI RIVER AND PROGGED TO REACH THE LOCAL FORECAST AREA BY
LATE AFTERNOON OR EARLY EVENING. FESTERING NOCTURNAL PRECIPITATION
IS EXPECTED TO OVERSPREAD THE FORECAST AREA THROUGH THE LATE MORNING
AND AFTERNOON HOWEVER WILL BE OUTRUNNING THE INSTABILITY...THUS
EXPECT PRECIP TO BE IN DECAYING STAGE WITH THE THREAT FOR THUNDER
MINIMAL. WARM AND MOIST ADVECTION THROUGH THE DAY WILL PUSH H85
TEMPS TO AROUND 17C WITH PWATS IN THE 1.8-2.0 INCH RANGE. THERE
REMAINS A CONCERN FOR AN OVERNIGHT MCS AS LOW LEVEL JET DEVELOPS
ACROSS THE MID MISSOURI VALLEY WITH CONVECTION SPREADING EAST INTO
THE FORECAST AREA LATE EVENING OR AROUND MIDNIGHT SATURDAY NIGHT AND
RIDING THE INSTABILITY GRADIENT ESE ACROSS THE REGION. WITH THE
STRONGEST INSTABILITY TO OUR SW AND CONTINUED MOISTURE/THETA-E
CONVERGENCE ASSOCIATED WITH THE VEERING LLJ OVERNIGHT...CORFIDI
VECTORS LESS THAN 5KT RAISE THE CONCERN FOR BACKBUILDING/TRAINING
CONVECTION WHICH COULD RESULT IN FLASH FLOODING. THE 12Z NAM SHIFTED
THE AXIS OF HEAVIEST PRECIP JUST SOUTH OF THE AREA WHICH MAY BE A
TREND WE SEE IN THE CONVECTIVE ALLOWING MODELS AS THEY COME INTO
RANGE OF THIS EVENT DEPENDING ON HOW THEY HANDLE THE LINGERING
CONVECTION DURING THE DAY SATURDAY. IF PRECIP DURING THE DAY
SATURDAY REINFORCES THE FRONT FARTHER SOUTH OR IMPEDES ITS NORTHWARD
ADVANCE...IT IS CONCEIVABLE THE HEAVIEST PRECIP COULD STAY OFF TO
OUR SOUTH LIKE THE NAM ADVERTISES. GIVEN THE PLACEMENT
CONCERNS...DONT HAVE ENOUGH CONFIDENCE TO ISSUE A FLASH FLOOD WATCH
AT THIS TIME...THOUGH ONE MAY BE NEEDED. SEVERE THREAT SATURDAY
NIGHT APPEARS LOW...WITH THE MAIN THREAT OUTSIDE OF FLASH FLOODING
BEING STRONG WINDS.

 

[ClicheVortex2014]

ILX doesn't say anything about severe potential. 

 

.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 245 PM CDT FRI JUL 10 2015

TIMING OF THUNDERSTORM ACTIVITY...AT LEAST INTO EARLY NEXT WEEK...IS
THE MAIN FORECAST CHALLENGE AS WE WILL BE POSITIONED ALONG THE
SOUTHERN PERIPHERY OF THE STRONGER FLOW ALOFT AS UPPER LEVEL RIDGING
BUILDS OVER THE SOUTHERN PLAINS. THIS IS GENERALLY A VERY FAVORABLE
LOCATION FOR NOCTURNAL THUNDERSTORMS TO OCCUR...DEPENDING ON
BOUNDARY LOCATION AND ORIENTATION OF THE LOW LEVEL JET.

THE CONVECTION THAT IS EXPECTED TO DEVELOP TO OUR WEST AND NORTHWEST
LATE TONIGHT WILL SPREAD EAST AND SOUTHEAST DURING SATURDAY MORNING
WITH OUR NORTH THE MORE FAVORED LOCATION FOR SCATTERED SHOWERS AND
THUNDERSTORMS. MODELS INDICATING THE LOW LEVEL JET WILL STILL BE
IN POSITION TO CONTINUE TO FEED HIGH THETA-E AIR NORTHEAST INTO THE
BACKSIDE OF THE MCS WHICH MAY CONTINUE THE STORM ACTIVITY OVER PARTS
OF WEST CENTRAL ILLINOIS INTO THE AFTERNOON HOURS. ANOTHER ROUND
OF CONVECTION IS THEN EXPECTED TO DEVELOP LATE SATURDAY NIGHT INTO
SUNDAY AND AGAIN...DEPENDING ON WHAT THE CONVECTION THAT OCCURS
SATURDAY DOES TO THE BOUNDARY LOCATION...WILL ULTIMATELY DECIDE
WHERE THE NEW CONVECTION FORMS OVERNIGHT SATURDAY INTO SUNDAY. THE
MORE FAVORED LOCATIONS WILL BE ACROSS THE NORTH AND EAST AS UPPER
LEVEL HEIGHTS AND WARMING TEMPERATURES ALOFT SHIFT THE GREATER RAIN
THREAT TO OUR NORTH BY LATER SUNDAY.

AFTER THAT...CONFIDENCE REALLY DROPS OFF WITH RESPECT TO COVERAGE
AND PLACEMENT OF THE GREATER THUNDERSTORM CHANCES LATE SUNDAY NIGHT
INTO MONDAY. MOST MODELS SHOWING EXTREME INSTABILITY LOCATED OVER
OUR AREA WITH MID LEVEL LAPSE RATES OF 8+ DGREES/KM...BUT 700 MB
TEMPS WARM TO BETWEEN +12 TO +14 DEGREES C WHICH MAY TEND TO
SUPPRESS THE STRONGER AND MORE PERSISTENT UPDRAFTS. THE LATEST ECMWF
DOES SHIFT A MORE SUBSTANTIAL SHORTWAVE SOUTHEAST INTO THE LOWER
GREAT LAKES BY TUESDAY WHICH SHOULD BRING A COOL FRONT SOUTHEAST
ACROSS THE AREA...WHICH MAY BRING A BREAK FROM THE DAILY CHANCES
FOR THUNDERSTORMS MIDWEEK. HOWEVER...WE HAVE SEEN THE MEDIUM RANGE
MODELS TEND TO OVERAMPLIFY THESE SOUTHEASTWARD MOVING TROFS INTO
THE LAKES RESULTING IN A MUCH TOO AGGRESSIVE PUSH TO THE COLD
FRONT INTO THE OHIO VALLEY WITH THE ULTIMATE FRONTAL LOCATION
MUCH FURTHER NORTH. WILL NEED TO SEE A BIT MORE CONSISTENCY WITH
THE UPPER PATTERN FORECAST FOR THE MIDDLE OF NEXT WEEK BEFORE MAKING
ANY SIGNIFICANT CHANGES TO THE EXTENDED FORECAST. UNTIL THEN...
LITTLE CHANGE FROM WHAT WE HAD IN THE FORECAST EARLIER...VERY WARM
AND HUMID WITH DAILY CHANCES FOR SHOWERS AND STORMS.

 

 

IWX says a little bit.

 

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 407 PM EDT FRI JUL 10 2015
WWD RETROGRESSION OF UPR RIDGE ACRS THE SRN US WILL
STEER ACTIVE NW FLW ALOFT INTO THE WRN LAKES THIS PD. FIRST RIDGE
RIDER OF NOTE OVERTOPS THE SRN PLAINS RIDGE SAT NIGHT DAMPENS
CONSIDERABLY EWD AND IN LIGHT OF 12Z CONSENSUS OF FAIRLY WK RTN
FLW/THETA-E RIDGING ALG W/SUBDUED MOS POPS FELT IT PRUDENT TO
BACKOFF PRIOR HIGH CHC POPS.

MORE VIGOROUS WARM SECTOR XPCD TO DVLP ON SUN IN RESPONSE TO BROAD
BUT DEEPENING LOW PRESSURE EXTENDING THROUGH THE NRN PLAINS. SFC
BASED DESTABILIZATION WITHIN BLDG LL THETA-E RIDGE LOOKS SUBSTANTIAL
ESP WEST HALF HWVR LL FLW WEAKNESS AND POSITION OF UPSTREAM RIDGE
SUGGESTS FLIPPING HIGHER POPS TO SUN NIGHT.

THEREAFTER VARIED AND UNCERTAIN MODEL SIGNALS BEYOND THAT EXCLUDE
ANYTHING BEYOND A CHC MENTION. WHILE PATTN ALOFT FVRS EPISODIC CONVN
AT TIMES...VAST DIFFS IN IMPLIED MODEL TIMING...UNCERTAIN UPSTREAM
CONV EVOLUTION/DOWNSTREAM MCV INFLUENCES AND SFC BNDRY POSITIONING
DICTATE A MORE CONSERVATIVE APCH THEN OFFERED BY ALLBLEND GUIDANCE.
HWVR EXTENT OF THETA-E RIDGING SEEN IN MOST SOLUTIONS SUN THROUGH
MON PREDICATE SOME SVR RISK LIKELY TO MANIFEST ALG W/A RENEWED FLOOD
THREAT GIVEN ANTECEDENT HYDRO CONDS.

 

ILN is the last in the region of interest to update their AFD. I suspect they'll at least say something... something like IND's.

[ClicheVortex2014]

WPC's new QPF has a bullseye on Indiana and west Ohio. I'm nervous about being in the bullseye this far out when outflow boundaries are so important.

 

 

[Quincy]

I'm not sure how you can't mention the threat with extreme instability progged to coincide with at least modest to moderate shear. Forecast wind fields support more of a damaging wind threat than anything, but we could be talking about significant severe, if the setup evolves close to current indications.

[ClicheVortex2014]

I was wondering why I was hearing about so many events in downtown Cincinnati on the radio... I totally forgot... this is MLB's All Star Weekend, and it's being held in Cincinnati this year.   Hope we get some really good storms to show off to the nation. I believe the Home Run Derby is on at 8PM Monday. Perfect timing.

 

ILN's afternoon AFD isn't as juicy as IND's, but better than ILX/LOT/IWX's

 

.LONG TERM /SUNDAY THROUGH FRIDAY/...
UNSETTLED WEATHER CONDITIONS ARE EXPECTED THROUGH THE EXTENDED
FORECAST PERIOD. BY SUNDAY MORNING...HIGH PRESSURE ALOFT WILL BE
SHIFTING WESTWARD INTO THE SOUTHERN PLAINS...WITH NORTHWEST FLOW
SETTING UP OVER THE REGION. WARM AND UNSTABLE CONDITIONS ARE
EXPECTED IN THE OHIO VALLEY (ESPECIALLY THE LOWER OHIO VALLEY)...AND
AS SHORTWAVES MOVE THROUGH THE QUICK FLOW ALOFT...CONVECTION WILL
BE OCCASIONALLY POSSIBLE.

MODEL AGREEMENT BEGINS THE EXTENDED PERIOD FAIRLY STRONG...BUT THE
STABILITY OF THE EXACT SOLUTIONS DETERIORATES WITH TIME...ESPECIALLY
FROM MONDAY NIGHT ONWARD. IT APPEARS THAT CONVECTION WILL BE LIKELY
ON SUNDAY (ESPECIALLY IN THE FIRST HALF OF THE DAY)...AND AGAIN ON
MONDAY AFTERNOON. ON BOTH DAYS...IT APPEARS THAT CONDITIONS WILL BE
FAVORABLE FOR SOME STORMS TO BE STRONG TO SEVERE...WITH SOME
ORGANIZED CONVECTIVE SYSTEMS WITHIN THE REALM OF POSSIBILITY.
CONVECTION WILL LIKELY CONTINUE TO BE OCCASIONALLY POSSIBLE THROUGH
REST OF THE WEEK...BUT IT WOULD BE VIRTUALLY IMPOSSIBLE TO TIME OUT
THE SHORTWAVES AND LOW-LEVEL FRONTAL POSITIONING AT THIS POINT IN
THE FORECAST CYCLE.

 

[Thundersnow12]

Who on earth knows where the frontal boundary will be after a few rounds of convection and possibly convection/cloud debris the day of but wow...the 18z GFS is putting out numbers I don't think I've seen here before (yeah the NAM has humungo off the charts CAPE if you click a sounding, cool) for this coming Monday, at least the LI. I can't remember a forecasted -16 LI before. After Sunday, the frontal boundary is progged in model land to slowly sink back south Monday afternoon across WI with a very explosive environment to its south. This run has SBCAPE over 6,000 j/kg, dew points in the mid-upper 70's and add to all that a 50kt mid-level jet max coming through. Not here to talk up a tornado threat, or even derecho...but just an environment conducive for big time atomic bomb thunderstorms. 

 

 

 

 

 

[Stebo]

You know the atmosphere is explosive when you have the surface theta-e into the white category on COD's page.

[andyhb]

Any kind of outflow boundary left to enhance low level shear is probably going to cause issues with such extreme destabilization.

[Thundersnow12]

You know the atmosphere is explosive when you have the surface theta-e into the white category on COD's page.

 

Yep, I love when we get the white maxed color

[brohnhdon]

4 consistent runs now of the GFS showing this pattern continuing through next weekend. Possibly a one-two punch in some areas if not 3+ MCS hits in some areas. It's certainly been a while since I've seen a week straight of model indicated CAPE >5000 J/kg. Then again, it is July. Really looking forward to this pattern given how this spring has gone.

[ClicheVortex2014]

Does anyone know a good way to track the EML plume on the models WITHOUT clicking on 500,000 soundings? I was thinking about looking at the 850mb Theta-e or humidity since the inversions tend to be there. Not sure if that's generally reliable though.

[kystormspotter]

Does anyone know a good way to track the EML plume on the models WITHOUT clicking on 500,000 soundings? I was thinking about looking at the 850mb Theta-e or humidity since the inversions tend to be there. Not sure if that's generally reliable though.

850mb temps? 

[brohnhdon]

Does anyone know a good way to track the EML plume on the models WITHOUT clicking on 500,000 soundings? I was thinking about looking at the 850mb Theta-e or humidity since the inversions tend to be there. Not sure if that's generally reliable though.

One parameter I suppose you could take a look at would be 700mb temperatures. What would be more helpful though is a mid-level lapse rate map. Given that CoD is often under the gun when it comes to MCS events, it would be in their best interest to add lapse rate products to their model site. I'll email them and see if I can't get that to happen before the severe ramps up in a few days.

[ClicheVortex2014]

850mb temps? 

Ah, that could work... nice and simple.

 

One parameter I suppose you could take a look at would be 700mb temperatures. What would be more helpful though is a mid-level lapse rate map. Given that CoD is often under the gun when it comes to MCS events, it would be in their best interest to add lapse rate products to their model site. I'll email them and see if I can't get that to happen before the severe ramps up in a few days.

Yeah that really would be nice.

[kystormspotter]

I was wondering why I was hearing about so many events in downtown Cincinnati on the radio... I totally forgot... this is MLB's All Star Weekend, and it's being held in Cincinnati this year.   Hope we get some really good storms to show off to the nation. I believe the Home Run Derby is on at 8PM Monday. Perfect timing.

 

ILN's afternoon AFD isn't as juicy as IND's, but better than ILX/LOT/IWX's

 

If the models hold or slightly speed up, the MLB will have a nice test on monday. Hopefully the MLB and meteorologist advising them make the right calls. Cincy is going to be packed monday night.