May 7-14 Severe Possibilities

[Tim from Springfield (IL)]

Not sure if the upcoming week is thread-worthy but this afternoon's Day 2 update for Saturday introduced a very narrow Slight risk from about Terre Haute east to Huntington, WV.  With Marginal extending to west of Keokuk and encompassing much of Central IL, Central/Southern IN, N KY and most of WV.

 

http://www.spc.noaa.gov/products/outlook/day2otlk.html

 

Also, the current Day 4 for Monday (May 9) pulled the 15% to southwest of STL (and more focus on S MO/AR/E OK/NE TX), but IIRC previous outlooks for Monday had as close as W IL/E IA included in the 15% risk area.  Also not ruling out more severe possibilities mid-late next week:

 

http://www.spc.noaa.gov/products/exper/day4-8/

ZCZC SPCSWOD48 ALL   ACUS48 KWNS 060858   SPC AC 060858   DAY 4-8 CONVECTIVE OUTLOOK     NWS STORM PREDICTION CENTER NORMAN OK   0358 AM CDT FRI MAY 06 2016   VALID 091200Z - 141200Z   ...DISCUSSION...   THE REMNANTS OF A CLOSED LOW EMERGING FROM THE INTERMOUNTAIN WEST   LATE THIS WEEKEND MAY SLOWLY SHIFT ACROSS THE CENTRAL PLAINS AND   MIDDLE MISSOURI VALLEY ON MONDAY.  HOWEVER...UNCERTAINTY CONCERNING    SMALLER-SCALE LOWER/MID TROPOSPHERIC DEVELOPMENTS ASSOCIATED WITH   THIS FEATURE CONTINUE TO INCREASE...AND THIS FEEDS BACK INTO   UNCERTAINTY CONCERNING RELATED CONVECTIVE POTENTIAL.  HOWEVER...IT   DOES APPEAR THAT SEVERE STORM POTENTIAL MAY BECOME MOST FOCUSED   ACROSS THE OZARK PLATEAU INTO ADJACENT PORTIONS OF THE MIDDLE   MISSISSIPPI VALLEY MONDAY AFTERNOON INTO MONDAY NIGHT.  THIS IS   EXPECTED TO COINCIDE WITH AN AREA OF STRONGER FORCING FOR ASCENT   PIVOTING AROUND THE SOUTHERN/SOUTHEASTERN PERIPHERY OF THE LOW...AND   ROUGHLY ALONG A 50-70 KT CYCLONIC 500 MB JET...WHERE SHEAR PROBABLY   WILL BECOME FAVORABLE FOR ORGANIZED CONVECTION...POSSIBLY INCLUDING   SUPERCELLS.   THEREAFTER...CONTINUED MOISTENING AND POTENTIAL DESTABILIZATION IS   EXPECTED ACROSS MUCH OF THE NATION EAST OF THE MISSISSIPPI   VALLEY...WITH THE EXCEPTION OF THE NORTHEAST...AND EVENTUALLY BACK   INTO THE SOUTHERN HIGH PLAINS....THROUGH MID TO LATE WEEK.    HOWEVER...MUCH UNCERTAINTY EXISTS CONCERNING THE PATTERN   EVOLUTION...PARTICULARLY AT SHORTER WAVELENGTHS.  AND SUB-15 PERCENT   SEVERE PROBABILITIES WILL BE MAINTAINED.

..KERR.. 05/06/2016

[Tim from Springfield (IL)]

The latest WPC 7-day outlook is also hinting at some hefty rain amounts for parts of the subforum, including perhaps 2+ in E IL/W IN, as well as W IL/S IA, between now and next Saturday:

 

http://www.wpc.ncep.noaa.gov/qpf/p168i.gif?1462588901

[Tim from Springfield (IL)]

Latest D1--and now I'm (barely) in the slight risk for this afternoon/evening.  And I should also add that Louisville is in the Slight as well--so hopefully this doesn't mess up the Derby later today:

 

http://www.spc.noaa.gov/products/outlook/day1otlk.html

SPC AC 071258   DAY 1 CONVECTIVE OUTLOOK     NWS STORM PREDICTION CENTER NORMAN OK   0758 AM CDT SAT MAY 07 2016   VALID 071300Z - 081200Z   ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OH VALLEY REGION...   ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL HIGH PLAINS...   ...THERE IS A MRGL RISK OF SVR TSTMS SURROUNDING OH VALLEY SLGT   RISK...   ...THERE IS A MRGL RISK OF SVR TSTMS ELSEWHERE FROM SRN ID TO NERN   KS AND SWRN KS TO SW TX...   ...SUMMARY...   SEVERE THUNDERSTORMS WILL BE POSSIBLE MAINLY THIS AFTERNOON AND   EVENING ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS AND THE OHIO   RIVER VALLEY.   --- TECHNICAL DISCUSSION ---   ...SYNOPSIS...   PREVIOUSLY SLOW-MOVING...OMEGA-SHAPED BUT NOT STRICTLY BLOCKED UPPER   PATTERN IS EXPECTED TO BECOME EVEN MORE PROGRESSIVE THIS PERIOD AS   THREE MAIN PROCESSES TAKE PLACE...   1.  MID/UPPER-LEVEL CYCLONE NOW OVER CHESAPEAKE BAY/DELMARVA REGION   WILL MOVE OFFSHORE MID ATLC BY 00Z AND DEVOLVE TO OPEN-WAVE CYCLONE.   THIS WILL RESULT FROM...   2.  STG SHORTWAVE TROUGH NOW OVER NWRN ONT AND FCST TO DIG SEWD   ACROSS UPPER GREAT LAKES THROUGH 06Z...REACHING PORTIONS NY/PA BY   12Z.   3.  LARGE CYCLONIC GYRE -- CURRENTLY CENTERED OVER GREAT BASIN AND   COVERING MUCH OF WRN CONUS -- SHIFTS SLOWLY ENEWD AS SERIES OF   SHORTWAVES ORBIT THIS FEATURE.  BASAL SHORTWAVE TROUGH -- NOW   EVIDENT IN MOISTURE-CHANNEL IMAGERY OVER CENTRAL/SERN AZ -- IS   EXPECTED TO EJECT NEWD TO CENTRAL/E-CENTRAL CO BY 00Z...WITH ERN   LOBE INTO W-CENTRAL KS.  THIS PERTURBATION WILL SHIFT NNEWD TO   CO/NEB BORDER REGION BETWEEN CYS-IML BY END OF PERIOD.   AT SFC...COLD FRONT WAS ANALYZED AT 11Z FROM NWRN QUE SWWD ACROSS   LH...LOWER MI...SRN LM...AND S-CENTRAL IA...BECOMING QUASISTATIONARY   WWD ACROSS CENTRAL AND SWRN NEB TO NEAR CYS RIDGE.  HYBRID   LEE-SIDE/FRONTAL-WAVE LOW WAS DRAWN NW AKO...WITH ANOTHER WEAK LOW   ALONG WRN EXTENSION OF FRONTAL ZONE IN NWRN CO.  WEAK/PAC FRONT   EXTENDED FROM NERN CO LOW SSWWD OVER CENTRAL/SRN NM.  THAT FRONT IS   EXPECTED TO WEAKEN FURTHER TODAY AS DRYLINE JUST TO ITS E BECOMES   BETTER-DEFINED ACROSS ERN CO...OK/TX PANHANDLES...SWD TO BIG BEND   REGION.  INVERTED TROUGH WAS DRAWN NWWD FROM NERN CO LOW...WHICH   SHOULD DEEPEN TODAY AS SHORTWAVE TROUGH APCHS.  FRONTAL ZONE MAY   SHIFT SOMEWHAT NWD OVER SERN NEB TOWARD EXTREME SERN WY.    MEANWHILE...COLD FRONT IS FCST TO PROCEED SEWD ACROSS REMAINDER   LOWER MI...LH...LE...AND NRN INDIANA TODAY...REACHING NWRN   PA...CENTRAL OH AND SRN IL BY 00Z.   ...OH VALLEY REGION...   WIDELY SCATTERED TO SCATTERED TSTMS SHOULD DEVELOP THIS AFTN ALONG   AND PERHAPS AHEAD OF COLD FRONT...OFFERING POTENTIAL FOR DAMAGING   GUSTS AND OCNL LARGE HAIL.  ACTIVITY SHOULD PERSIST/SHIFT SEWD   ACROSS PORTIONS WV/VA APPALACHIANS THIS EVENING...SVR POTENTIAL   DIMINISHING AS TSTMS ENCOUNTER PROGRESSIVELY MORE STABLE BOUNDARY   LAYER.  AGGREGATED COLD POOL MAY DEVELOP...HOWEVER..SO SVR   PROBABILITIES HAVE BEEN ADJUSTED SLIGHTLY SEWD TO ACCOUNT FOR THAT   POSSIBILITY.   SFC LOW...WHICH MAY ALREADY BE DEVELOPING ALONG COLD FRONT OVER SRN   LOWER MI...IS FCST TO DEEPEN AND SHIFT ESEWD THROUGH AFTN ACROSS LE.   MEANWHILE NARROW PLUME OF LOW-LEVEL MOISTENING WILL OCCUR S OF FRONT   WITH .5-.8 INCH PW AND SFC DEW POINTS 40S F OVER ERN AREAS TO NEAR   60 W.  MOIST ADVECTION WILL BE OFFSET SOMEWHAT BY DIABATICALLY   DRIVEN HEATING/MIXING...BUT STILL SHOULD SUPPORT PREFRONTAL SFC-   BASED EFFECTIVE-INFLOW PARCELS AND MLCAPE IN 500-1500 J/KG RANGE   THIS AFTN.  THOUGH SFC WINDS WILL HAVE SUBSTANTIAL WLY COMPONENT...   VEERING/STRENGTHENING OF FLOW WITH HEIGHT WILL CONTRIBUTE TO 35-45   KT EFFECTIVE-SHEAR MAGNITUDES...SUPPORTING BLEND OF MULTICELLS...   TRANSIENT SUPERCELLS AND PERHAPS BOWS.   ONE POTENTIAL INHIBITING FACTOR IS THAT THIS AREA WILL BE UNDER   SHORTWAVE RIDGING DURING AFTN...WITH APPRECIABLE LARGE-SCALE DCVA   REMAINING FARTHER NW AND BEHIND FRONT.  REGARDLESS...SUFFICIENT   LOW-LEVEL HEATING/LIFT SHOULD OCCUR IN CONCERT WITH FRONTAL LIFT TO   REMOVE CINH.  THAT...IN TURN...WILL SUPPORT WIDELY SCATTERED TO   SCATTERED CONVECTION WITHIN FAVORABLE PARAMETER SPACE OF BUOYANCY   AND DEEP SHEAR.  SOMEWHAT GREATER MOISTURE IS EXPECTED WITH WWD   EXTENT WHILE LIFT WILL INCREASE EWD.

[HillsdaleMIWeather]

New SPC Day 4-8 mentions daily severe weather possible somewhere in the Conn US for at least 8 days straight, mentioned severe weather could be possible in the Great Lakes but of course models are deviating.

[Tim from Springfield (IL)]

Few changes on the 1630 Day 1:

 

http://www.spc.noaa.gov/products/outlook/day1otlk.html

[Tim from Springfield (IL)]

MD #546 hints a possible Severe Thunderstorm Watch for parts of C/S IL, S IN, and N KY including Louisville/Churchill Downs later this afternoon:

 

http://www.spc.noaa.gov/products/md/md0546.html

MESOSCALE DISCUSSION 0546   NWS STORM PREDICTION CENTER NORMAN OK   0145 PM CDT SAT MAY 07 2016   AREAS AFFECTED...PORTIONS OF SRN IL...SWRN IND...NRN KY   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE    VALID 071845Z - 072115Z   PROBABILITY OF WATCH ISSUANCE...60 PERCENT   SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND   INTENSITY LATE THIS AFTERNOON AND EVENING AND POSE A RISK FOR   DAMAGING WINDS AND ISOLATED LARGE HAIL. TRENDS ARE BEING MONITORED   AND A SEVERE THUNDERSTORM WATCH IS POSSIBLE PRIOR TO 21Z.   DISCUSSION...MESOANALYSIS AT 18Z SHOWS A SURFACE LOW OVER SOUTHEAST   LOWER MICHIGAN WITH A COLD FRONT TRAILING SOUTHWEST ACROSS CENTRAL   SECTIONS OF INDIANA/ILLINOIS. THE PRE-FRONTAL AIR MASS CONTINUES TO   WARM/DESTABILIZE...AND CONTINUED HEATING IN THE PRESENCE OF   LOWER/MID 50S SURFACE DEW POINTS SHOULD RESULT IN POCKETS OF   MODERATE SURFACE-BASED INSTABILITY BY LATE AFTERNOON.    A FEW BRIEF/STRONG STORMS HAVE DEVELOPED OVER WEST-CENTRAL INDIANA   THIS AFTERNOON...AND WEAKENING INHIBITION AND FRONTAL CONVERGENCE   SHOULD RESULT IN ADDITIONAL DEVELOPMENT ALONG/IN ADVANCE OF THE   FRONT OVER THE NEXT FEW HOURS. LARGELY UNIDIRECTIONAL LOW-MID LEVEL   WIND FIELDS AND 35-40 KTS OF DEEP-LAYER SHEAR SHOULD RESULT IN   SOUTHEAST-MOVING CLUSTERS OF STORMS WITH A RISK FOR DAMAGING WINDS.   RELATIVELY STEEP MID-LEVEL LAPSE RATES COMBINED WITH SUFFICIENT   SHEAR FOR UPDRAFT ORGANIZATION MAY ALSO RESULT IN ISOLATED LARGE   HAIL WITH THE STRONGEST STORMS.   CONVECTIVE TRENDS WILL BE MONITORED AND A SEVERE THUNDERSTORM WATCH   IS POSSIBLE FOR PARTS OF THE DISCUSSION AREA PRIOR TO 21Z.   ..BUNTING/HART.. 05/07/2016

[HillsdaleMIWeather]

Said watch is out, line formed in Central IL

[Chambana]

Looks like a nice healthy little cell formed near Arcola. Litchfield Illinois getting some nice rainfall. 2"+ rainfall amounts are a lock this week for areas of Illinois.

[SchaumburgStormer]

Down in St. Louis for the birds game. Severe storms just missed us to the north, but got some heavy rain. Luckily the game had ended minutes before the storm came in.

[Central Illinois]

Down in St. Louis for the birds game. Severe storms just missed us to the north, but got some heavy rain. Luckily the game had ended minutes before the storm came in.

yea looks like you got lucky. I heard Nokomis area had 2"+ of rain. Good game to be at...I was at the Thursday game they won 4-0 vs PHI

[ConvectiveIA]

As of Sunday morning 17:54 UTC radar and satellite show decent showers and thunderstorms over northeast Kansas that are moving into northwest MO up to the IA border. AM regional forecast discussions seem to rule out any chance of these making it up to south central (Des Moines) IA this afternoon but the latest radar and satellite loops seem to hint that they just might nudge up and clip DSM.

 

Any thoughts on this?

 

Also was hoping for high-lightning storms to rock IA tonight-Tuesday but I still feel a bit of uncertainty given the current ingredients.

[Tim from Springfield (IL)]

Today's Day 4 outlook for Wednesday has a small 15% for most of MO and SW IL (south and west of Decatur).

 

http://www.spc.noaa.gov/products/exper/day4-8/

 DAY 4-8 CONVECTIVE OUTLOOK     NWS STORM PREDICTION CENTER NORMAN OK   0359 AM CDT SUN MAY 08 2016   VALID 111200Z - 161200Z   ...DISCUSSION...   MODELS GENERALLY INDICATE LOW PREDICTABILITY TO PATTERN DEVELOPMENTS   DURING THIS PERIOD...PARTICULARLY AT THE SHORTER WAVELENGTHS...AND   EXTENDED TIME FRAME /FOR THIS OUTLOOK...THE LATTER HALF OF THIS   COMING WORK WEEK INTO NEXT WEEKEND/.  AS A RESULT...SEVERE WEATHER   POTENTIAL REMAINS A BIT UNCLEAR...BUT THERE IS LITTLE READILY   EVIDENT TO SUGGEST MUCH BEYOND RELATIVELY MODEST SEVERE WEATHER   POTENTIAL FOR THE TIME OF YEAR.   ONE AREA WITH POTENTIAL FOR ORGANIZED SEVERE STORM DEVELOPMENT DOES   APPEAR INCREASINGLY APPARENT FOR WEDNESDAY ACROSS PARTS OF THE LOWER   MISSOURI/MIDDLE MISSISSIPPI VALLEY...WHERE GUIDANCE IS SUGGESTIVE   THAT SIZABLE CAPE MAY BE PRESENT IN RESPONSE TO A CONTINUED INCREASE   IN BOUNDARY LAYER MOISTURE.  ON THE SOUTHERN PERIPHERY OF A BROAD   CLOSED LOW MIGRATING FROM THE NORTHERN PLAINS TOWARD THE UPPER   MISSISSIPPI VALLEY....A PLUME OF WARM ELEVATED MIXED LAYER AIR   APPEARS LIKELY TO ADVECT NORTHEAST OF THE U.S./MEXICAN PLATEAU   REGION.  FORCING FOR ASCENT ASSOCIATED WITH LOWER/MID TROPOSPHERIC   WARM ADVECTION...ON THE NOSE OF THIS PLUME...MAY CONTRIBUTE TO THE   EVOLUTION OF AN UPSCALE-GROWING MESOSCALE CONVECTIVE SYSTEM.  AIDED   BY 30-40 KT FLOW BETWEEN 850 AND 700 MB...WIND PROFILES/SHEAR APPEAR   FAVORABLE FOR A FORWARD PROPAGATING CONVECTIVE SYSTEM CAPABLE OF   GENERATING POTENTIALLY DAMAGING WIND GUSTS AND PERHAPS LARGE HAIL.    PROBABILITIES FOR THIS CURRENTLY APPEAR HIGHEST ROUGHLY ALONG THE   INTERSTATE 70 CORRIDOR BETWEEN KANSAS CITY AND ST. LOUIS...PERHAPS   INITIATING NEAR KANSAS CITY WEDNESDAY MORNING.   ..KERR.. 05/08/2016

[HillsdaleMIWeather]

The 12Z GFS shows maybe some severe thunderstorms in Michigan, Indiana, Ohio Wednesday night through Thursday, especially during the day Thursday.

[janetjanet998]

.MO INTO WRN IL  
 
A DISTURBANCE ALOFT IS FORECAST TO PRECEDE THE MAIN SHORTWAVE  
TROUGH...RAPIDLY MOVING NEWD ACROSS MO WITH SUBSTANTIAL HEIGHT FALLS  
AND LIFT. STRONG WARM ADVECTION WILL DEVELOP BY AFTERNOON IN THE  
WAKE OF EARLY RAIN/WEAK THUNDERSTORMS WHICH WILL RESULT IN  
DESTABILIZATION AND INCREASING SHEAR PROFILES WITH SRH ON THE ORDER  
OF 200-300 M2/S2. WITH A DIFFUSE WARM FRONT IN PLACE...A FEW SEVERE  
STORMS CAPABLE OF HAIL AND ALSO A TORNADO OR TWO CANNOT BE RULED  
OUT. HOWEVER...LACK OF STRONG INSTABILITY AND POTENTIAL FOR AIRMASS  
CONTAMINATION LENDS UNCERTAINTY TO THIS AREA.  

[IllinoisWedges]

If anyone missed it, the SPC issued a Day 3 SLGT for portions of Illinois, Missouri, and Iowa. MPAS is also fun to look at. 

 

 

 

...MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHERN PLAINS...
WITHIN THE LARGER-SCALE NORTHERN BRANCH TROUGH...A SIGNIFICANT SHORT
WAVE IMPULSE EMERGING FROM THE INTERMOUNTAIN WEST APPEARS LIKELY TO
TURN EAST OF THE CENTRAL ROCKIES...THROUGH PORTIONS OF THE
MIDDLE/LOWER MISSOURI VALLEY BY LATE WEDNESDAY NIGHT. AHEAD OF THIS
FEATURE...A PLUME OF WARM ELEVATED MIXED-LAYER AIR APPEARS LIKELY TO
CONTINUE ADVECTING ACROSS PARTS OF THE SOUTHERN AND CENTRAL PLAINS
INTO THE LOWER MISSOURI/MIDDLE MISSISSIPPI VALLEY REGION DURING THE
DAY WEDNESDAY.

ON THE NORTHEASTERN PERIPHERY OF THIS PLUME...GUIDANCE REMAINS
SUGGESTIVE THAT AN AREA OF ENHANCED MID-LEVEL FORCING FOR UPWARD
VERTICAL MOTION MAY SUPPORT INITIATION OF THUNDERSTORM DEVELOPMENT
NEAR THE MISSOURI RIVER NORTH OF KANSAS CITY...PERHAPS BY MIDDAY.
THIS IS EXPECTED TO OCCUR IN THE PRESENCE OF A THERMODYNAMIC
ENVIRONMENT CHARACTERIZED BY MOIST LOW-LEVELS...STEEP MID-LEVEL
LAPSE RATES AND LARGE CAPE...WHICH SHOULD BE CONDUCIVE TO SEVERE
STORMS...AND POTENTIAL FOR CONSIDERABLE UPSCALE CONVECTIVE GROWTH.


LINGERING STRONGER CYCLONIC MID-LEVEL FLOW MAY REMAIN MOSTLY TO THE
COOL SIDE OF THE APPROACHING FRONT...BUT A BELT OF MODEST LOWER/MID
TROPOSPHERIC FLOW WITHIN THE WARM SECTOR MAY CONTRIBUTE TO FAVORABLE
SHEAR FOR THE EVOLUTION AND MAINTENANCE OF A FORWARD-PROPAGATING
MESOSCALE CONVECTIVE SYSTEM. THIS PROBABLY WILL BE ACCOMPANIED BY
THE RISK FOR DAMAGING WIND GUSTS...IN ADDITION TO LARGE HAIL...AS IT
TENDS TO ADVANCE EASTWARD AND SOUTHEASTWARD ACROSS MISSOURI AND
ADJACENT PORTIONS OF THE MIDDLE MISSISSIPPI VALLEY THROUGH WEDNESDAY
EVENING.

 

[A-L-E-K]

not gonna happen

[IllinoisWedges]

not gonna happen

you're most likely right. this pattern blows. 

[RCNYILWX]

not gonna happen

No flow, no go. I'm a bit surprised any part of the LOT CWA is in the Slight for Weds considering the lack of midlevel (500 and 700 mb) and low level (850 and 925 mb) flow and resultant lack of deep layer and low level shear. That's on top of the other issues, including lower level stability and questions about whether there is much mucape at all (GFS is much more bullish than NAM on advecting steeper midlevel lapse rates and higher mucape, while NAM has very poor lapse rates).

[RyanDe680]

If anyone missed it, the SPC issued a Day 3 SLGT for portions of Illinois, Missouri, and Iowa. MPAS is also fun to look at. 

That looks like a July/Aug radar

[cyclone77]

NAM is really lagging behind the instability axis with it's mid-upper support for Wed.  GFS and Euro are better, but lower 3km is trash.  If we can get the higher instability that some of the models dish out, then maybe we can still get a decent linear MCS out of this thing.  Iowa/Missouri would stand best shot, with MCS crapping out somewhat after it crosses the Mississippi.    

[nwohweather]

NAM currently showing pretty high LIs and a solid 25-35 kts of shear with SRH in excess of 100 m2/s2 for Thursday afternoon here. Not saying lock it in with it being the NAM a few days out but definitely a tad intriguing. Regardless both the GFS and NAM show ample heat and instability for Thursday

[Chinook]

You may want to watch tomorrow for a sneaky slight risk day in IN/IL. Currently the SPC has a slight risk for western KY tomorrow. The NAM has fairly high CAPE values over 2000 J/kg in southern IN and IL with 40 kt wind at 500mb.

[Chicago Storm]

A few tors in the DVN CWA today near the WF.

 

We've seen a few of these events produce quite well the past few weeks, many of which surprisingly well.

 

I expect more of the same tomorrow in  MO/IL/IN/KY.

[snowlover2]

You may want to watch tomorrow for a sneaky slight risk day in IN/IL. Currently the SPC has a slight risk for western KY tomorrow. The NAM has fairly high CAPE values over 2000 J/kg in southern IN and IL with 40 kt wind at 500mb.

Local met was showing a futurecast radar that showed a pretty nice line of storms moving through here tomorrow evening. Thinks SPC needs to move risk area northward.

[tornadohunter]

Nam and nam 4km both increase backing. South Indiana/Kentucky look interesting tomorrow

[snowlover2]

As some expected, new day 1 has slight and marginal shifted north with possible enhanced in later outlooks.

 

DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1258 AM CDT TUE MAY 10 2016

   VALID 101200Z - 111200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VALLEY INTO THE
   OH VALLEY...

   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS CNTRL AND NRN TX...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM THE ERN DAKOTAS SWWD INTO
   NEB...KS...AND NERN CO...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM THE MID MS VALLEY EWD INTO
   VA...

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS MUCH OF CNTRL TX INTO
   FAR SERN OK...

   ...SUMMARY...
   SCATTERED SEVERE STORMS ARE LIKELY TUESDAY ACROSS PARTS OF THE
   MIDDLE MISSISSIPPI AND LOWER OHIO VALLEYS...FROM CENTRAL INTO NORTH
   TEXAS...AND ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS. HAIL
   AND WIND ARE POSSIBLE IN ALL AREAS...WITH A TORNADO OR TWO POSSIBLE
   ACROSS THE OHIO VALLEY.

   ...SYNOPSIS...
   A SHORTWAVE TROUGH WILL MOVE FROM THE MIDDLE MS VALLEY EWD ACROSS
   THE OH VALLEY DURING THE DAY...AND WILL WEAKEN OVERNIGHT AS IT
   APPROACHES THE MID ATLANTIC. TO THE W...A MORE INTENSE UPPER LOW
   WILL MOVE SLOWLY NEWD ACROSS THE NRN HIGH PLAINS...WITH A 60-70 KT
   MIDLEVEL SPEED MAX ARCING CYCLONICALLY INTO THE DAKOTAS.

   AT THE SURFACE...LOW PRESSURE WILL BE CENTERED OVER WRN ND AS WELL
   AS OVER THE OK/TX PANHANDLES BY LATE AFTERNOON...WITH A DIFFUSE WARM
   FRONT FROM THE MID MS VALLEY EWD ACROSS THE OH VALLEY. MOIST SLY
   FLOW AND COOL TEMPERATURES ALOFT WILL MAINTAIN A LARGE AREA OF
   INSTABILITY ACROSS THE SRN PLAINS INTO THE LOWER AND MIDDLE MS
   VALLEY AND EWD ACROSS THE OH AND TN VALLEYS TO SUPPORT SCATTERED
   SEVERE STORMS.

   ...MID MS INTO THE OH VALLEY...
   A BROAD AREA OF THUNDERSTORM POTENTIAL WILL EXIST FOR MUCH OF THE
   PERIOD...WITH AREAS OF EARLY THUNDERSTORMS INCREASING UNCERTAINTY.
   INITIALLY...THUNDERSTORMS ARE EXPECTED TO BE OVER THE MID MS/LOWER
   OH VALLEY TUE MORNING...IN ASSOCIATION WITH THE SHORTWAVE TROUGH AND
   ON THE OF A SWLY LOW-LEVEL JET. THESE STORMS WILL MOVE EWD AND MAY
   EVENTUALLY REJUVENATE AS INSTABILITY INCREASES FROM THE SW MOISTURE
   ADVECTION AND HEATING. LATER IN THE DAY...THE STRONGEST INSTABILITY
   WILL BE PRESENT OVER MO INTO SRN IL AND WRN KY/TN BUT THE SHORTWAVE
   TROUGH WILL BE LIFTING NEWD. STILL...LIFT DUE TO WARM ADVECTION AND
   COLD PROFILES ALOFT SHOULD RESULT IN ADDITIONAL STORMS FORMING
   ACROSS SRN IL INTO THE LOWER OH VALLEY...AND SHIFTING EWD WITH TIME.
   LARGE HAIL...DAMAGING WINDS...AND A COUPLE TORNADOES WILL BE
   POSSIBLE AS HODOGRAPHS FAVOR SUPERCELLS. AN ENHANCED RISK CORRIDOR
   COULD BE ADDED IN LATER OUTLOOKS ONCE UNCERTAINTY IS REMOVED LATER
   TODAY.

 

 

[snowlover2]

New day 2

 

DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1259 AM CDT TUE MAY 10 2016

   VALID 111200Z - 121200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM A PORTION OF THE CNTRL AND
   SRN PLAINS INTO THE MID MS VALLEY REGION...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM A PORTION OF THE CNTRL AND
   SRN PLAINS INTO THE MS VALLEY AND OH VALLEY...

   ...SUMMARY...
   SEVERE THUNDERSTORMS ARE POSSIBLE FROM THE MIDDLE MISSISSIPPI VALLEY
   REGION INTO THE SOUTHERN PLAINS WEDNESDAY AND WEDNESDAY EVENING.

   ...SYNOPSIS...

   BLOCKING PATTERN WILL PERSIST WEDNESDAY WITH PRIMARY FEATURE OF
   INTEREST BEING A SYNOPTIC TROUGH THAT WILL SLOWLY MOVE FROM THE NRN
   PLAINS/CNTRL ROCKIES TO THE UPPER MS VALLEY/CNTRL PLAINS BY 12Z
   THURSDAY. AT THE SFC A SYNOPTIC LOW WILL DEVELOP THROUGH SRN
   MANITOBA WHILE TRAILING COLD FRONT ADVANCES THROUGH THE PLAINS AND
   MID-UPPER MS VALLEY REGION. BY THE END OF THIS FORECAST PERIOD THE
   FRONT SHOULD EXTEND FROM WI SWWD THROUGH NRN AND SWRN TX. A WARM
   FRONT WILL LIKELY EXTEND FROM A WEAK SFC LOW OVER KS THROUGH SRN
   PORTION OF THE OH VALLEY EARLY WEDNESDAY. THIS BOUNDARY MAY MOVE
   SLOWLY NWD DURING THE DAY.

   ...MIDDLE MS VALLEY THROUGH SRN PLAINS...

   THUNDERSTORMS WILL LIKELY BE IN PROGRESS FROM NRN KS INTO NEB AND
   INTO A PORTION OF NRN MO/WRN IA WITHIN ZONE OF STRONGER ISENTROPIC
   ASCENT NORTH OF WARM FRONT AND ON NOSE OF LLJ. MORNING ACTIVITY IS
   EXPECTED TO GRADUALLY WEAKEN AS IT SHIFTS EWD DURING THE DAY. WARM
   SECTOR SHOULD BECOME MODERATELY TO STRONGLY UNSTABLE FROM THE SRN
   PLAINS TO MIDDLE MS VALLEY WHERE EML PLUME WITH STEEP /7.5-8.5 C/KM/
   MID-LEVEL LAPSE RATES WILL ADVECT EWD ABOVE A MOIST BOUNDARY LAYER
   WITH DEWPOINTS GENERALLY IN THE UPPER 60S F CONTRIBUTING TO
   2000-3000 J/KG MLCAPE. WHILE THE BOUNDARY LAYER MAY REMAIN CAPPED
   INTO THE EARLY AFTERNOON...LOW AMPLITUDE IMPULSES ROTATING THROUGH
   BASE OF UPPER TROUGH AND FRONTAL CONVERGENCE SHOULD EVENTUALLY
   RESULT IN THUNDERSTORM INITIATION FROM MO SWWD THROUGH ERN KS INTO
   OK AND NWRN TX. ADDITIONAL STORMS MAY DEVELOP ALONG/NORTH OF WARM
   FRONT FROM NRN MO INTO SRN IA.

   IN GENERAL...STRONGER WINDS ALOFT WILL REMAIN NORTH OF WARM SECTOR
   RESULTING IN WEAK VERTICAL SHEAR AND SUPPORTING MOSTLY MULTICELL
   STORM STRUCTURES WHERE PRIMARY THREATS WILL BE LARGE HAIL AND
   DAMAGING WIND GUSTS. AN EXCEPTION WILL BE FROM NERN KS INTO THE NRN
   MO/SRN IA WHERE BACKED NEAR-SFC WINDS AND PROXIMITY TO AN EJECTING
   MID-LEVEL IMPULSE WILL RESULT IN SHEAR PROFILES FAVORABLE FOR A FEW
   SUPERCELLS IN VICINITY OF THE WARM FRONT. ANOTHER POTENTIAL AREA OF
   MORE ORGANIZED STORMS AND POSSIBLE SUPERCELLS MIGHT EVOLVE BY EARLY
   EVENING OVER NWRN TX INTO SWRN OK. HERE...BELT OF STRONGER MID-LEVEL
   WINDS ACCOMPANYING A SHORTWAVE TROUGH MAY OVERSPREAD SWRN EXTENSION
   OF THE FRONT NEAR THE DRYLINE/COLD FRONT INTERSECTION. STORMS MAY
   EVENTUALLY EVOLVE INTO MULTICELL LINES/CLUSTERS AS THEY DEVELOP EWD
   BEFORE WEAKENING LATER IN THE EVENING
 

 

[ConvectiveIA]

Here in DSM we essentially were skanked short by the last few days of storms. Just to our west and south and even a little to our east they got nailed especially Nebraska and Kansas. Last night even Western Iowa saw severe storms and tornado warnings. South Central Iowa was kind of caught in a stable patch of airmass and lacked sun too.

 

Wednesday's prospects look slightly better, and the shape of the SPC outlook gives me a better feeling this time (Weds) but we will see. The storms could very well fire up hardcore in MO/IL and again and miss us because we're just not in the center of the focus.

[Indystorm]

The enhanced risk has shown up in the Ohio Valley for today as anticipated.  06 NAM shows quite the possibilities from south of St. Louis. to PAH and over to Louisville today.  May become rather interesting.

[snowlover2]

The enhanced risk has shown up in the Ohio Valley for today as anticipated.  06 NAM shows quite the possibilities from south of St. Louis. to PAH and over to Louisville today.  May become rather interesting.

Slight risk up to I-70 in IN/W OH. Can't say i'm surprised since we have had some sun here this morning.