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Tn Valley Severe Weather 2017

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Day 3 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0224 AM CDT Tue Mar 28 2017

   Valid 301200Z - 311200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
   WEST TN...EASTERN AR...AND NORTHERN MS...

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
   THE LOWER/MID MS VALLEY AND TN VALLEY...

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
   THE LOWER/MID MS VALLEY...AND INTO THE OH/TN VALLEYS...

   ...SUMMARY...
   Severe thunderstorms are expected on Thursday from parts of the
   middle and lower Mississippi Valley into the Tennessee Valley.

   ...Lower/Mid MS Valley into TN Valley...
   A strong upper trough will continue moving eastward across the
   southern Plains and into the mid/lower MS valley on Thursday. 
   Thunderstorms are expected to form during the afternoon along/ahead
   of the cold front/dryline over AR/LA and track eastward into MS/TN. 
   Forecast soundings indicate the potential for strong CAPE ahead of
   the front, along with favorable shear profiles for organized/severe
   storms.  Model solutions are quite consistent on the position of
   main trough axis, but the details of shortwave timing/locations are
   quite diverse.  Nevertheless, a consensus of guidance provides
   sufficient confidence to upgrade a portion of western TN, eastern
   AR, and northern MS to an ENH risk for Thursday.

Storm Prediction Center Mar 28  2017 0730 UTC Day 3 Severe Thunderstorm Outlook.png

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Sad news in the storm chasing world today. :cry: Three storm chasers were killed in a violent intersection crash that took place about 3 miles west of Spur, Texas at 3:30 P.M. Central time. Here is an article on it.- http://www.accuweather.com/en/weather-news/three-storm-chasers-die-in-car-crash-on-tuesday-afternoon/70001248 Two of the chasers were very well known, Kelley Williamson and Randy Yarnall were well known storm chasers who worked for TWC bringing live on sight severe storm coverage to the many people at home. Of those also lost Corbin Jaegar was also killed in the collision who was also storm chasing. This personally hurt a lot as I typically watched Kelleys livestreams a lot. Any way I got onto his Youtube channel to see if he was covering the severe weather in Texas when I noticed the video seemed cut short I skipped to the end to see the video and the audio and video blanked out before an intersection. I figured out a few minutes later they had passed. We never know when our time will come but we should not live our lives in fear I suppose. They will be missed by many thousands of people including myself personally, let them rest in peace, and who knows perhaps they are up there storm chasing with the angels! I apologize if this is off-topic but I felt it was right I mentioned it.

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5 hours ago, BlunderStorm said:

Sad news in the storm chasing world today. :cry: Three storm chasers were killed in a violent intersection crash that took place about 3 miles west of Spur, Texas at 3:30 P.M. Central time. Here is an article on it.- http://www.accuweather.com/en/weather-news/three-storm-chasers-die-in-car-crash-on-tuesday-afternoon/70001248 Two of the chasers were very well known, Kelley Williamson and Randy Yarnall were well known storm chasers who worked for TWC bringing live on sight severe storm coverage to the many people at home. Of those also lost Corbin Jaegar was also killed in the collision who was also storm chasing. This personally hurt a lot as I typically watched Kelleys livestreams a lot. Any way I got onto his Youtube channel to see if he was covering the severe weather in Texas when I noticed the video seemed cut short I skipped to the end to see the video and the audio and video blanked out before an intersection. I figured out a few minutes later they had passed. We never know when our time will come but we should not live our lives in fear I suppose. They will be missed by many thousands of people including myself personally, let them rest in peace, and who knows perhaps they are up there storm chasing with the angels! I apologize if this is off-topic but I felt it was right I mentioned it.

It's not an off topic to me.I always enjoyed watching KW in a chase.Sad news :(

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Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1243 AM CDT Wed Mar 29 2017

   Valid 301200Z - 311200Z

   ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THURSDAY
   AFTERNOON AND EVENING OVER PARTS OF NORTHERN MS...WESTERN AND MIDDLE
   TN...NORTHWEST AL...AND SOUTHWEST KY...

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
   CENTRAL MS NORTHWARD INTO SOUTHERN IL/IN...

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
   LOWER AND MIDDLE MS VALLEYS...AND INTO THE OH/TN VALLEYS...

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
   LOWER AND MIDDLE MS VALLEYS...AND INTO THE OH/TN VALLEYS...

   ...SUMMARY...
   An active severe weather event is forecast for Thursday over parts
   of the middle and lower Mississippi Valley into the Tennessee
   Valley.

   ...Northern MS/Northwest AL/Western and Middle TN/Southwest KY...
   A strong upper trough will rotate across the southern/central Plains
   today, and into the lower/mid MS Valley on Thursday.  Models suggest
   that thunderstorm activity from the Day1 period will be waning in
   most areas by Thursday morning, while the primary cold front remains
   over central AR/LA.  This should allow for some heating and
   destabilization to occur ahead of the front, with re-development of
   thunderstorms during the afternoon near the MS River.  A strong
   mid-level speed max (50+ knots at 700mb) will rotate across the cold
   front during the afternoon, promoting strong low-level and deep
   layer vertical shear profiles.  Forecast soundings show 0-3km SRH
   values of 200-300 m2/s2 and MLCAPE of 1500 J/kg.  Several 00z cam
   solutions that extend into the Day2 period indicate discrete
   supercell mode will be preferred with the activity, suggesting a
   favorable environment for tornadoes, large hail, and damaging winds.
    Strong tornadoes and very large hail will be possible in the MDT
   risk area.  The eastward extent of low level moisture will be a
   limiting factor to how far east the significant severe threat will
   develop.  Nevertheless, strong to severe storms may reach eastern
   KY/TN and parts of AL during the evening.

   ...MO/IL/IN...
   It appears the risk for severe storms will also extend northward
   into parts of MO/IL/IN during the day as activity blossoms ahead of
   the approaching shortwave trough.  This area will likely experience
   more cloud cover on Thursday, limiting the confidence in sufficient
   instability.  Nevertheless, hail and damaging wind will be possible
   in the stronger cells.

Storm Prediction Center Mar 29  2017 0600 UTC Day 2 Convective Outlook.png

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NAM sounding for southwest Tennessee tomorrow (21z) shows pretty high parameters, including 51 kt of effective shear and 2980 J/kg of CAPE

q6Q5fxg.png

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 Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1228 PM CDT Wed Mar 29 2017

   Valid 301200Z - 311200Z

   ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR NORTHERN
   MISSISSIPPI INTO WESTERN AND MIDDLE TENNESSEE AND WESTERN
   KENTUCKY...

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
   MISSISSIPPI NORTHWARD INTO THE LOWER TENNESSEE AND LOWER OHIO
   VALLEYS...

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
   THE CENTRAL GULF COAST NORTHWARD INTO THE MIDDLE MISSISSIPPI AND
   OHIO VALLEYS...

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
   SLIGHT RISK...

   ...SUMMARY...
   Severe thunderstorms potentially capable of damaging winds, isolated
   tornadoes, and hail are forecast on Thursday over parts of the
   middle and lower Mississippi Valley into the Ohio and Tennessee
   Valleys.

   ...Middle and lower MS Valley eastward into the TN and OH Valleys...

   Complex forecast for Thursday with considerable uncertainty
   regarding specific details of the overall forecast scenario owing in
   part to prior thunderstorm activity on Wednesday and Wednesday night
   through early Thursday.  Some model solutions exhibit favorable
   buoyancy/shear for the possible development of significant severe
   thunderstorms during peak heating while other solutions suggest a
   more mesoscale-dependent severe risk to develop within the area
   generally defined within the 30% severe probabilities (category 3
   risk).  Early-day clouds/thunderstorm activity will likely modulate
   both low-level moisture and 700-500mb lapse rates across the MS
   Valley.  This is reflected in the variability of the most recent
   model guidance with the NAM implying intense storms redeveloping
   across the northern half of MS northward into the lower OH Valley. 
   This is in contrast to the latest GFS and ECMWF models showing
   widespread thunderstorms in a band during the morning near the MS
   River moving east with little recovery/destabilization expected in
   its wake.  Yet, some cooling aloft in association with the
   approaching mid-level low/cold pocket will contribute to
   destabilization, in addition to surface heating during the day in
   wake of early-day clouds/thunderstorms.  A cold front is forecast to
   slowly progress across the MS Valley and serve as a focus for
   renewed thunderstorm development, perhaps as early as midday.  As
   previously described, considerable variability in the magnitude of
   buoyancy is depicted in model guidance.  Nonetheless, upwards of
   500-1500 J/kg is forecast within an area of strong cyclonically
   curved 500-mb flow.  Forecast soundings show strong effective shear
   (40-60 kt) which will likely result in storm organization and an
   attendant risk for wind damage.  The strength of the low-level shear
   will conditionally augment a tornado risk for any mature supercells
   or mesovortices in a squall line.  Hail will be possible both near
   the cold pocket with strong updrafts and in areas where mid-level
   lapse rates are less convectively contaminated.  The broken bands of
   storms will move east in eastern parts of KY/TN and the eastern
   portions of the central Gulf Coast during the evening and overnight
   with a gradual weakening in storm intensity and expected severe
   coverage.

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NAM sounding for southwest Tennessee tomorrow (21z) shows pretty high parameters, including 51 kt of effective shear and 2980 J/kg of CAPE

q6Q5fxg.png&key=1823d7636ad377c0bc169da158618f6693cdddb5eba7704cbb153302cf03428d


Northern Hardin County

Sent from my SM-G900R7 using Tapatalk

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 Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0101 AM CDT Thu Mar 30 2017

   Valid 301200Z - 311200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
   PARTS OF ILLINOIS AND INDIANA AND SOUTHWEST OHIO SOUTH ACROSS THE
   TENNESSEE VALLEY TO CENTRAL MISSISSIPPI...

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID AND
   LOWER MISSISSIPPI VALLEY ACROSS THE OHIO VALLEY TO THE
   APPALACHIANS...AND SOUTH TO THE GULF COAST...

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
   SLIGHT RISK AREA...AND EXTENDING TO THE GEORGIA/SOUTH CAROLINA
   COASTAL AREA...

   ...SUMMARY...
   Severe thunderstorms potentially capable of damaging winds,
   tornadoes, and hail are forecast on Thursday over parts of the
   middle and lower Mississippi Valley into the Ohio and Tennessee
   Valleys.

   ...Synopsis...
   An upper low crossing eastern Kansas early in the period is forecast
   to accelerate eastward across Missouri and into the Midwest through
   the period -- as a vigorous short-wave over the Pacific Northwest at
   the start of the period digs southeastward with time, evolving into
   a deepening closed low with time and reaching the Arizona/Utah
   border region by the end of the period.

   As the eastern upper low is kicked eastward by the digging western
   system, short-wave troughing -- within broader cyclonic flow
   surrounding the low -- will move quickly eastward out of the
   southern Plains and across the Gulf of Mexico and Gulf coastal
   states.  This will facilitate a rather rapid eastward advance of a
   surface cold front across the southeast quarter of the country. 
   This front -- trailing southward from a parent low moving across the
   Ohio Valley states through the afternoon and evening -- should
   extend from the southern Appalachians to the Florida Panhandle
   vicinity by 31/12z.

   ...The Midwest south to the Gulf Coast, and the Mississippi Valley
   east to the Appalachians...
   A very complex weather scenario continues to unfold -- complicated
   largely by ongoing showers and locally strong to severe storms now
   affecting the middle and lower Mississippi Valley area.  Models
   suggest that much of this convection will be contained within two
   distinct clusters at the start of the period -- one crossing the mid
   Mississippi Valley into the lower Ohio Valley area, and a second
   crossing southern and eastern Mississippi/eastern Louisiana.  The
   Ohio Valley convection is forecast to gradually weaken through the
   morning hours, while the southern cluster of convection may persist
   -- in a locally severe manner -- across the central Gulf coastal
   region.

   This convection and associated cloud cover continues to cast
   uncertainty with respect to areas of potentially greater insolation
   and thus destabilization, but it appears that at least modest
   instability will evolve along and ahead of the advancing cold front
   -- which should extend southward from a western Illinois surface low
   roughly along the Mississippi River around midday.  With mixed-layer
   CAPE values likely reaching 500 to 1500 J/kg by early afternoon in
   the wake of prior convection, new storm development should begin. 
   Organization of the storms will be augmented by strong lower- and
   middle-tropospheric south-southwesterly flow, and though turning
   with height will remain limited in most areas, speed shear suggests
   both rotating storms and small-scale bowing segments will evolve
   with time.  Along with potential for hail, damaging winds are
   expected, and a few tornadoes will be possible as well --
   particularly over the lower Ohio Valley area where a more
   southeasterly component to the surface flow should exist ahead of
   the low and in the vicinity of the warm front.  Convection may
   organize into a broken band, spreading eastward across the Ohio and
   Tennessee Valleys and central Gulf coastal states through the
   afternoon and evening, along with attendant severe potential.

   With areas of most concentrated risk difficult to discern, a broad
   ENH/level 3 risk area is being included, with slight/level 2 risk
   being expanded eastward at this time -- both across the mid Ohio
   Valley along the mid-level low track, as well as across the southern
   Appalachians region as a rapidly advancing short-wave trough fosters
   increasing ascent through the evening and overnight hours.

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SPC - Talk about walking it back. That's a massive decrease. Good for us, though.

Sent from my SM-G900R7 using Tapatalk

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Here's the latest Discussion from MRX:

.LONG TERM (Tonight through Wednesday)...A negative upper trough
will move across the Ohio and Tennessee Valleys tonight and early
Friday morning. A series of jet streaks exiting the upper trough
will produce divergence aloft over the region late today through
early Friday morning. These circulation around this jets will
enhance the fronto-genetic forcing overnight.

Models show the airmass becoming moderately unstable with MLCAPES
of 1000-1500 J/Kg with Hail CAPEs of 150-300 J/kg. Shear/SR
Helicity does become quite strong with favorable values for
rotating updrafts with incoming storms. LCL heights lower
overnight as well. Models show a 850mb jet of 40-50kts overnight. Given
these parameters, isolated tornadoes are a concern with the main
threat being damaging winds up to 60 mph and hail of 0.5 to 1
inch.

SPC has placed essentially the entire area under a slight risk of
severe thundestorms, even though the western/southern half of the
area seems to have the greatest threat.

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