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jaxjagman

Tn Valley Severe Weather

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Oh the weather outside is frightful, literally! Midday was robust in Louisiana including that tornado emergency for Alexandria. This afternoon looks a little more linear for North Mississippi. Strongest shear is ejecting away from Louisiana and southern Mississippi; however as of 3pm Central those south cells remain robust.

Greater and forecast instability allowed this event to escalate day 1. Also it appears the LLJ was a little less veered through midday, compared to progged over the weekend. Little details make a big difference in Dixie. Y'all be safe!

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Tornado on the ground in southern MS:

The National Weather Service in Jackson has issued a

* Tornado Warning for...
  Southern Lincoln County in south central Mississippi...
  Southeastern Franklin County in southwestern Mississippi...

* Until 345 PM CST.

* At 250 PM CST, a confirmed tornado was located near Smithdale, or 8
  miles north of Liberty, moving northeast at 35 mph.

  HAZARD...Damaging tornado and half dollar size hail.

  SOURCE...Radar 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.

* This tornadic storm will be near...
  Little Springs around 305 PM CST.
  Center Point around 310 PM CST.
  West Lincoln around 325 PM CST.
  Bogue Chitto around 330 PM CST.
  Enterprise around 335 PM CST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.
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Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0350 AM CST Mon Dec 23 2019

   Valid 261200Z - 311200Z

   ...DISCUSSION...
   Minimal severe thunderstorm potential is evident across the CONUS on
   Day 4/Thursday as an upper low moves over northern Mexico towards
   parts of the Southwest. Deterministic medium-range guidance
   continues to diverge from Day 5/Friday onward regarding the
   evolution of this upper low across the central/eastern CONUS. If a
   slower eastward movement occurs, this would potentially allow for
   greater low-level moisture return. Regardless of its eventual
   development, enhanced flow aloft attendant to the upper trough/low
   should foster strong vertical shear. However, instability is
   forecast to remain rather weak in both the 00Z GFS and ECMWF. Still,
   some severe threat may materialize from Day 5/Friday through Day
   8/Monday over parts of the southern Plains, lower/mid MS Valley into
   the TN Valley, and Southeast. However, uncertainty in the location
   and amplitude of the upper trough/low and related surface features,
   along with concerns about weak instability, suggest predictability
   remains too low to include any severe probabilities.

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Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1130 PM CST Fri Dec 27 2019

   Valid 291200Z - 301200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY AFTERNOON
   AND EVENING ACROSS PARTS OF THE MID SOUTH AND CENTRAL GULF COAST
   REGION...

   ...SUMMARY...
   Strong thunderstorms may impact parts of the Mid South and central
   Gulf States vicinity Sunday afternoon and evening, with at least
   some potential for a few to become severe, accompanied by a risk for
   damaging wind gusts and perhaps a tornado or two.

   ...Synopsis...
   Large-scale mid/upper troughing likely will encompass much of the
   Rockies, Plains and Mississippi Valley by 12Z Sunday, with a fairly
   deep embedded occluding cyclone centered over the mid Missouri
   Valley region and a significant short wave impulse turning eastward
   into the base of the trough across the southern Plains.  The short
   wave is forecast to remain progressive, and models suggest that it
   will pivot in negatively-tilted fashion while accelerating across
   the middle Mississippi/lower Ohio Valley region, around the
   southeastern periphery of the cyclone, as another significant short
   wave perturbation digs toward the southern California coast.  It
   appears that this will be accompanied by considerable
   intensification of lower/mid tropospheric wind fields across much of
   the Mississippi Valley through the Appalachians, and may contribute
   to support for renewed cyclogenesis across the Great Lakes region by
   late Sunday night.

   While the initial and developing secondary surface cyclones may
   encompass a broad area, with a potentially sizable warm sector, it
   still appears that considerable cloud cover, associated rain, and
   otherwise generally weak lapse rates will inhibit boundary layer
   destabilization, particularly from the Ohio River northward.  Even
   east of the lower Mississippi Valley, where surface dew points are
   forecast to increase through the 60s, models continue to indicate
   that mixed-layer CAPE may maximize in the 250-500 J/kg range Sunday
   afternoon and evening.

   ...Mid South/central Gulf States...
   Severe weather potential for Sunday through Sunday night still
   appears largely conditioned on sufficient warm sector
   destabilization.  East of the lower Mississippi Valley, forecast
   soundings indicate moist low-level profiles supportive of
   boundary-layer based instability, though with very limited CAPE due
   to weak lapse rates.  It is still not certain that this environment
   will become supportive of appreciable severe weather potential, but
   it might marginally be enough given the forecast strengthening of
   lower/mid-tropospheric wind fields through the day, and favorable
   large-scale forcing for ascent.

   South to southwesterly winds in the 850-500 mb layer, within the
   warm sector, are forecast to strengthen to 50-70+ kt through the day
   across the lower Mississippi and Tennessee Valleys.  Vertical shear
   for boundary-layer based storms will be strong and conducive to
   organized severe convection, including potential for one or more
   evolving lines and discrete supercells.

   At least some model output suggests that a developing low-level
   confluence zone could become one focus for the initiation and
   intensification of storms, well ahead of the surface cold front,
   across Alabama into eastern Tennessee by late Sunday afternoon. 
   However, confidence is greater that a corridor of forcing for
   ascent, along/just ahead of the eastward advancing front, will
   become the primary focus for any possible vigorous convective
   development.  It appears that this may advance east of the lower
   Mississippi Valley by early afternoon, before continuing
   northeastward and eastward through the Tennessee Valley and at least
   northern portions of Mississippi/Alabama by Sunday evening.  

   Potentially damaging surface gusts aided by downward momentum
   transport seems the most prominent/widespread possible severe
   hazard, but a couple of isolated tornadoes may not be out of the
   question.

   ...MAXIMUM RISK BY HAZARD...
   Tornado:   2%     - Marginal
   Wind:      5%     - Marginal
   Hail:     <5%     - None
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The first wave strengthened as it moved north and east, bringing quite a bit of lightning to the Tri-Cities. We had roughly five minutes of absolutely torrential rain with a breeze that sent sheets onto the window. It sounded for all the world like someone spraying the window with a garden hose from a few feet away. 

As for the second wave which featured the line responsible for the warning around Knoxville, I saw velocities as high as 84 MPH depicted just prior to the warning's issuance. KMRX's beam height is roughly 2500-3000 ft at that point, so there was likely no ground truth. That said...

0100 AM     NON-TSTM WND GST 4.3 W GATLINBURG        35.72N 83.57W
12/30/2019  M84 MPH          SEVIER             TN   MESONET

            COVE MOUNTAIN OBSERVATION SITE RECORDED AN
            84 MPH GUST. THE HIGHEST SUSTAINED WIND WAS
            34 MPH.
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 Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0357 AM CST Mon Jan 06 2020

   Valid 091200Z - 141200Z

   ...DISCUSSION...
   A multi-day severe weather episode is expected across portions of
   the Arklatex into the Deep South vicinity on D5/Fri and D6/Sat. The
   ingredients for severe thunderstorms will being to fall into place
   Day 4/Thu as an upper ridge spreads eastward across the eastern U.S.
   and a large-scale trough intensifies across the western states. At
   the surface, a strong surface pressure gradient will develop from
   the Midwest to the western Gulf Coast, allowing rich Gulf moisture
   to begin streaming northward across east TX and the lower MS Valley
   vicinity on Thursday.  

   The warm sector will expand through the day on Friday from eastern
   OK/TX eastward across much of the TN Valley and Gulf Coast states.
   Surface dewpoints are expected to be impressive for this time of
   year, climbing into the mid 60s to low 70s as a deepening surface
   low shifts eastward across OK/TX on Friday. This will occur as the
   western trough ejects eastward into the southern Plains and an
   intense southerly low level jet overspreads the region. Forecast
   guidance also shows a weak EML emanating from the Mexican Plateau
   spreading over parts of the region, providing a weak cap that should
   limit warm sector convection initially. Confidence has increased
   that a strong vertical shear parameter-space will overlay a
   high-quality warm sector ahead of the ejecting trough and a
   southeastward-advancing cold front Friday afternoon through Friday
   night. As such, a 30% severe delineation has been included for parts
   of the Arklatex within the broader 15% severe probability area.

   On Day 6/Sat, severe thunderstorm potential is expected to continue
   into portions of the TN Valley and the northern Gulf Coast vicinity.
   Similar to Friday, intense shear parameters and adequate instability
   will exist across the region as the upper trough becomes more
   compact and lifts northeast across the mid/lower MS Valley to the OH
   Valley. 15% severe probabilities will be maintained at this time as
   questions remain with respect to how pristine the warm sector will
   remain over MS/AL and vicinity, as well as timing/location of key
   surface features. That being said, the overall pattern will support
   severe thunderstorms into Saturday evening across much of the Deep
   South vicinity. 

   Confidence in severe potential beyond Day 6/Sat is low, though
   guidance suggests stormy conditions could return to parts of the
   Southeast on Monday/Monday night.

   ..Leitman.. 01/06/2020

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Day 4-8 Convective Outlook    NWS Storm Prediction Center Norman OK  0357 AM CST Mon Jan 06 2020  Valid 091200Z - 141200Z  ...DISCUSSION...  A multi-day severe weather episode is expected across portions of  the Arklatex into the Deep South vicinity on D5/Fri and D6/Sat. The  ingredients for severe thunderstorms will being to fall into place  Day 4/Thu as an upper ridge spreads eastward across the eastern U.S.  and a large-scale trough intensifies across the western states. At  the surface, a strong surface pressure gradient will develop from  the Midwest to the western Gulf Coast, allowing rich Gulf moisture  to begin streaming northward across east TX and the lower MS Valley  vicinity on Thursday.    The warm sector will expand through the day on Friday from eastern  OK/TX eastward across much of the TN Valley and Gulf Coast states.  Surface dewpoints are expected to be impressive for this time of  year, climbing into the mid 60s to low 70s as a deepening surface  low shifts eastward across OK/TX on Friday. This will occur as the  western trough ejects eastward into the southern Plains and an  intense southerly low level jet overspreads the region. Forecast  guidance also shows a weak EML emanating from the Mexican Plateau  spreading over parts of the region, providing a weak cap that should  limit warm sector convection initially. Confidence has increased  that a strong vertical shear parameter-space will overlay a  high-quality warm sector ahead of the ejecting trough and a  southeastward-advancing cold front Friday afternoon through Friday  night. As such, a 30% severe delineation has been included for parts  of the Arklatex within the broader 15% severe probability area.  On Day 6/Sat, severe thunderstorm potential is expected to continue  into portions of the TN Valley and the northern Gulf Coast vicinity.  Similar to Friday, intense shear parameters and adequate instability  will exist across the region as the upper trough becomes more  compact and lifts northeast across the mid/lower MS Valley to the OH  Valley. 15% severe probabilities will be maintained at this time as  questions remain with respect to how pristine the warm sector will  remain over MS/AL and vicinity, as well as timing/location of key  surface features. That being said, the overall pattern will support  severe thunderstorms into Saturday evening across much of the Deep  South vicinity.   Confidence in severe potential beyond Day 6/Sat is low, though  guidance suggests stormy conditions could return to parts of the  Southeast on Monday/Monday night.  ..Leitman.. 01/06/2020



That’s some serious wording for 5 days out.


.

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47 minutes ago, PowellVolz said:

 


That’s some serious wording for 5 days out.


.

 

Looks like a flood potential is going to be real.Pattern reminds me of last year when we see these lows develop to our SW and track right through TN.

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River systems controlled by dams should likely be OK initially as many of the lakes are already at low pool and can handle the influx.  That said, probably the bigger concern would be urban streams and rivers not controlled by dams.  We haven't had much flooding up here(NE TN) yet.  The ground is fairly saturated, so thunderstorms training over one area would be a big concern.   Fortunately, only the tops of the eastern mountains have snow and not a lot.  If there was 12-18" of snowpack, we would be in serious trouble on this side of the valley.  You all in the mid-state seem to have had more rains just based on observations in this forum.  The far eastern valley has a little wiggle room but not much.

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The 12Z ECMWF is pretty lit (verbatim) Saturday. Oh I'm glad I saved the best for last. Winter is choking, so I'm ready to talk severe!

Most notably, the Euro has a southern stream system to spark convection in the Deep South. Surface low going into the Midwest may have unidirectional winds aloft. The South, on the other hand, should have veering with height.

Next feature is a long-shot in January, but the Euro shows a secondary boundary in North Mississippi to North Alabama, south of the synoptic WF. Should the coastal warm front merge with this boundary, it'll be more believable. At any rate Friday night rain sets up the possible outflow boundary OFB I'm talking about. Winter set-up means an even higher than usual possibility of a morning rain induced stable bust Tenn Valley. I'd need the coastal front to merge with the OFB to give it more spark.

Now Alabama may be capped. This whole OFB and moderate cap would be wonderful in the Plains in May. Dixie in January? It could work, but I'm not holding my breath. Few more days to watch this.

Mississippi looks less capped as the southern short-wave induces cooling aloft. Still great wind profiles ahead of the trough. Mississippi is also favored in winter climo. Alabama is more February and later. We'll see though. 

30% generates a lot of social media hype, but this is typical Dixie in winter - very conditional. Wind fields are there but instability is always TBD. While I'm eagerly watching (though not holding my breath) chances are I end up watching college basketball most of Saturday in my nice dry living room.

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 Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0359 AM CST Tue Jan 07 2020

   Valid 101200Z - 151200Z

   ...DISCUSSION...
   A multi-day severe weather episode is expected Day 4-5/Fri-Sat from
   the Arklatex into the Deep South vicinity. An intense mid/upper
   trough over the Four Corners and northwest Mexico early on Friday
   will eject eastward into the southern Plains by 12z Saturday. At the
   surface, low pressure will develop over TX and shift east/northeast
   toward central AR by 12z Saturday. Ahead of the low, rich Gulf
   moisture will stream northward across eastern TX/OK and expand
   eastward across the lower MS Valley and Gulf Coast states through
   Saturday. 60s F dewpoints are forecast to extend as far north as the
   lower OH Valley by Saturday morning, with upper 60s to near 70s
   dewpoints over parts of the Arklatex on Friday into much of
   LA/MS/AL/GA on Saturday. This anomalously rich and broad warm sector
   will reside beneath a 50-70 kt southerly low level jet and 80+ kt
   southwesterly 500 mb jet streak. While some questions remain over
   how pristine the warm sector ahead of the surface low and cold front
   will remain, especially on Saturday, this kinematic and
   thermodynamic parameter-space will support severe thunderstorms
   capable of all severe hazards from the Arklatex into the TN
   Valley/Gulf Coast states Friday and Saturday. Mixed convective modes
   are anticipated given the strength of shear, with a QLCS likely
   developing ahead of the surface cold front. This will support
   damaging gusts and mesovortex tornado potential. Additionally, any
   semi-discrete convection that develops ahead of the QLCS will be in
   an environment capable of supporting supercells and tornadoes,
   especially from east TX through central MS/AL. 

   Beyond Saturday, a reprieve from severe potential is expected on Day
   6/Sun as high pressure builds over the east and the surface cold
   front stalls near the southeast Atlantic coast and northern Gulf
   coast. However, some severe potential could return early next week
   as a mean trough is forecast to persist across the western half of
   the country while shortwave impulses eject east/northeast from the
   southern Plains through the Midwest on Day 7-8/Mon-Tue. Confidence
   in how much the airmass will be able to recover and destabilize
   remains in question, as the southeastern U.S. is forecast to receive
   quite a bit of rain. As such, confidence is too low to include
   severe probs at this time.

   ..Leitman.. 01/07/2020

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And 30% is posted for our parts of our Forum Region! Where's the siren emoji?

My thoughts are similar to those from Monday. GFS is a bit fast, ECMWF is slower, truth may be in between. Regardless the 12Z Euro is total eye candy. Still early for soundings*; but, the constant level plots are lit. So is the surface.

* Friend reminded me it's also too early for meso-scale forecasts (outflow, cap, etc) and that's right. However it is my decision point, more than a forecast. Mesoscale will determine my chase status. If not, plenty of college basketball on Saturday. KU hoops is on on CBS!

As for my snow post from Monday, I'm sorry if I raised false hope north of I-40. What a disaster! Guess I was jacked up on severe wx thoughts.

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SPC talked about a secondary WF in the vicinity of MAla, MMiss creating a cap north of that boundary. ICON is trying to show that now.


.

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Yes at one point Alabama looked capped on the Euro following stabilizing Friday night rain. Euro has consistently hammered Mississippi Saturday. I'm less concerned about caps now. NAM going nearly unidirectional upstairs is a real party pooper for fans of intense severe weather though.

Saturday is still the back half of the NAM (as of Thursday writing) where NAM accuracy falls off. However the accuracy issue is usually on mesoscale details. Upper wind fields is a larger scale issue. I'm afraid the GFS/Euro will trend toward the semi-unidirectional NAM. Sure it has helicity off the charts, but that is mostly speed shear. Turning is meh on the NAM. It would be a strong but sloppy line.

Now the GFS and Euro both still have a classic winter Dixie outbreak. Still sloppy, but it's relative down here. GFS/Euro start turning 700 mb wind, with 500 mb southwest or better. NAM has 700 mb barely west of south and 500 mb still SSW. They all have a mess at 200 mb, but the GFS/Euro have enough turning up to 500 mb for a lot of severe wx and some tornadoes. Plus they all have robust LLJs.

Instability is marginal, but that is normal in winter severe weather. Tonight or Friday morning, one could check fcst soundings for where that instability lies Saturday; low level or mid-level. If low level (just a few thousand ft AGL) it only takes a few hundred CAPE for severe. If mid-level only it's tough to light the candle. Such mesoscale detail isn't clear until about a day to 36 hours ahead.

If everything comes together, one would expect that secondary warm front originating from the Gulf Coast front. Worst action would be from there south. Otherwise it's a sloppy rain-out and I'm watching college basketball all day Saturday. :popcorn:

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Short range models are showing alot more instability.Memphis got bumped up from a slight to moderate risk.

 

Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0652 AM CST Fri Jan 10 2020

   Valid 101300Z - 111200Z

   ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS NORTHEAST
   TX...SOUTHEAST OK...NORTHERN LA...CENTRAL/SOUTHERN AR...

   ...SUMMARY...
   Widespread severe thunderstorms are likely across the southern Great
   Plains, mainly this afternoon and evening, spreading east into the
   Lower Mississippi Valley tonight. The most dangerous corridor for
   strong tornadoes and intense damaging winds should be centered on
   northeast Texas through northern Louisiana and southern Arkansas
   this evening through the overnight.

   ...South-Central States...
   An outbreak of severe thunderstorms is possible later today through
   tonight, with the most dangerous portion being tonight into early
   Saturday morning with a potential derecho and embedded strong
   tornado risk. Primary changes this outlook are to expand the
   Moderate Risk east across the Lower MS Valley and increase tornado
   probabilities for the evening/overnight period.

   Vigorous shortwave trough near the AZ/NM border will shift east
   across the southern Great Plains through 12Z Saturday. A powerful
   90+ kt jet at 500 mb is expected to emanate out of the base of the
   trough across east TX/OK. In response to this trough, the LLJ will
   increase throughout the period, more notably late in the period.
   Along the northwest periphery of low-level moisture advancement,
   multiple elevated supercells are expected to develop this morning
   across parts of western/northern OK into southern KS. A large hail
   risk is anticipated initially, but convection will have an
   opportunity to become surface based towards midday, though discrete
   cells should not be particularly common as a polar front sags into
   this region.

   Farther south, strong boundary-layer heating is expected across west
   TX where 0-3 km lapse rates are forecast to approach 9 C/km. At the
   same time, strong mid-level height falls will spread across the
   Pacific cold front/dryline by peak heating, and thunderstorms should
   easily develop along the eastern edge of this steeper lapse-rate
   plume. Scattered supercells will evolve from east-central OK to
   north-central TX by 19-21Z, and farther south into south-central TX
   during the late afternoon. This activity will be strongly sheared
   and could produce very large hail early in the convective cycle.
   With time, multi-scale forcing will encourage consolidation into an
   extensive QLCS that should accelerate toward the Ark-La-Tex region
   during the evening. Damaging winds will likely be common along the
   QLCS with embedded mesovortex and supercell tornadoes. 

   Guidance such as the 00Z HRW-NSSL and HRW-ARW, along with the 06Z
   NAM and 11Z HRRR suggest that pre-frontal convection should develop
   out ahead of the QLCS across the Sabine Valley towards 06Z. As this
   convection spreads northeast across northern LA towards the
   Ark-La-Miss, the strong tornado potential should increase amid
   strengthening 0-1 km SRH of 300+ m2/s2 and upper 60s surface dew
   points. A couple long-track tornadoes are possible given fast storm
   motions but convective mode should be messy. Consolidation with the
   accelerating upstream QLCS should eventually occur, sustaining
   potential for widespread damaging winds with embedded significant
   severe gusts and tornadoes as it spreads toward the Lower MS Valley
   through 12Z.

   ..Grams/Mosier.. 01/10/2020
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 Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1126 AM CST Fri Jan 10 2020

   Valid 111200Z - 121200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR
   MISSISSIPPI...ALABAMA...PARTS OF WESTERN TENNESSEE...SOUTHEAST
   LOUISIANA...AND THE WESTERN FLORIDA PANHANDLE...

   ...SUMMARY...
   Severe thunderstorms capable of damaging winds and tornadoes are
   expected across parts of the southeastern U.S. on Saturday.  A risk
   for damaging wind gusts will include parts of the Ohio Valley and
   Mid-Atlantic states.

   ...Synopsis...
   An intense mid-level shortwave trough will rapidly move from the
   southern Great Plains to the Lower Great Lakes late Saturday night. 
   In the low levels, a surface low initially over east-central AR will
   develop northeast towards central IN by early evening and
   subsequently to the NY Adirondacks by Sunday morning.  A warm front
   will advance northward into parts of the OH Valley and Mid-Atlantic
   states while a cold front sweeps east across the central Gulf Coast
   and OH Valley.  

   ...TN/MS/LA/AL/GA/FL Panhandle...
   A squall line with a risk for severe gusts will be ongoing Saturday
   morning from near the OH/MS River confluence south-southwestward
   into coastal LA and the west-central Gulf of Mexico.  Intense wind
   fields associated with a 100-kt 500mb jet and an 80-kt southerly LLJ
   will gradually shift east/northeastward during the period in
   association with the progression of the mid-level trough.  Strong
   low-level mass response and associated advection processes will
   support the poleward transport of lower 60s degrees F dewpoints into
   middle TN and upper 60s farther south near I-20.  Intense background
   flow fields and associated very large hodographs will support both
   the threat for severe gusts with bowing segments in the squall line
   and a conditional risk for tornadoes with any supercell managing to
   develop ahead of the squall line or with stronger mesovortices.  The
   risk for significant severe gusts will likely focus with more
   pronounced bowing segments and longer-lived mesovortices.  As the
   squall line advances across AL into GA late in the day, models are
   indicating less organization in the line as it encounters slightly
   weaker instability concurrent with the upper system becoming
   increasingly displaced from the GA/north FL vicinity.  

   ...OH Valley...
   The northern periphery of the severe risk (damaging gusts and
   perhaps a brief tornado) will likely extend into the OH Valley
   associated with the northern part of the squall line expected to
   develop Friday night into Saturday morning.  Intense wind fields
   coupled with a few hundred J/kg MUCAPE would seemingly support a
   conditional risk for damaging gusts with a fragmented convective
   band as far north as OH to the southeast of the forecast surface low
   track.  

   ...Carolinas north into VA/MD...
   The latest model guidance shows at least weak instability (MUCAPE
   ranging from 250 J/kg north to 1000 J/kg south) as flow strengthens
   during the evening into the overnight.  CAM guidance suggests the
   possibility for a re-invigoration of storms east of the Appalachians
   as low-middle 60s surface dewpoints infiltrate the Carolina/VA
   Piedmont.  Damaging gusts appear to be the primary risk with this
   activity during the 04-12z period.

   ...MAXIMUM RISK BY HAZARD...
   Tornado:  10% SIG - Enhanced
   Wind:     30% SIG - Enhanced
   Hail:      5%     - Marginal

   ..Smith.. 01/10/2020

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