SEVERE WEATHER THREAT FOR TEXAS,THEN SHIFTING EASTWARD

This briefing was from SPC this morning prior to the upgrade to High Risk...

JRnOldsmar wrote:

Yup.  Sis outside of Charleston has been warned to keep an eye on things.

Hope she heeds your words, the warnings are flying

Kamala Severe Warnings

sangria wrote:

JRnOldsmar wrote:

Yup.  Sis outside of Charleston has been warned to keep an eye on things.

Hope she heeds your words, the warnings are flying

Kamala Severe Warnings

That she does, San. She went through Hugo and that was all the lesson one needs. 90% of her neighborhood was basically destroyed.

JRnOldsmar wrote:

sangria wrote:

JRnOldsmar wrote:

Yup.  Sis outside of Charleston has been warned to keep an eye on things.

Hope she heeds your words, the warnings are flying

Kamala Severe Warnings

That she does, San.  She went through Hugo and that was all the lesson one needs.  90% of her neighborhood was basically destroyed.

That's my girl!!
From Sis:
Got 3 weather alerts going off at once here. Radar has warning box just north of us for the moment and the closet is ready if I need it.

JRnOldsmar wrote:

That's my girl!!
From Sis:
Got 3 weather alerts going off at once here. Radar has warning box just north of us for the moment and the closet is ready if I need it.

Good for her!! Brad Panovich actually did a FB stream today about how to prepare, including having the closet ready.

19Z HRRR just finished running, I slowed it down so that it was easier to look at the time stamp as well....




Significant Tornado Parameter




Total QPF....  

Maybe it will send some rain your way San...

Updated Day 1 Outlook




SPC AC 051959

  Day 1 Convective Outlook  
  NWS Storm Prediction Center Norman OK
  0259 PM CDT Wed Apr 05 2017

  Valid 052000Z - 061200Z

  ...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST GA
  INTO CENTRAL SC...

  ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
  HIGH FROM PORTIONS OF SC TO CENTRAL KY...

  ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
  MODERATE FROM PORTIONS OF THE SOUTHEAST AND MID-ATLANTIC TO PORTIONS
  OF THE OH VALLEY...

  ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST
  SOUTHWARD TO THE GULF AND SOUTHEAST ATLANTIC COASTS...

  ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
  OF THE EASTERN STATES...

  ...SUMMARY...
  An outbreak of severe thunderstorms is underway from portions of the
  Southeast States to the Ohio Valley region and eastward to the
  Mid-Atlantic. Significant tornadoes will be possible, especially
  from parts of southeastern Georgia into South Carolina, and also
  from parts of eastern Alabama into south-central Kentucky. In
  addition, very large hail, and damaging wind gusts are expected.

  ...Discussion on Outlook Adjustments...
  The follow changes are made to the ongoing outlook:

  1) The high risk (driven by 30-percent tornado probability) has been
  focused along/east of ongoing linear segments with embedded
  supercellular structures. Discrete cells ahead of this convection,
  as well as the aforementioned embedded cells, will continue to pose
  a risk for tornadoes, a few of which could be strong, considering a
  warm/moist boundary-layer environment characterized by ample
  effective storm-relative helicity. Indeed, as of 1945Z, a tornadic
  debris signature has been observed in Laurens County, GA.

  10-percent tornado probabilities have been contracted to points
  near/south of the Ohio River. To the north, sufficient low-level
  moisture return appears unlikely, suggesting a lower tornado
  potential.

  2) 45-percent wind probabilities are introduced across portions of
  the Ohio Valley southward to far northern Tennessee. Surface dew
  points have steadily risen into the 50s, with temperatures climbing
  into the mid 70s to near 80. Convection should increase in coverage
  this afternoon, with an initial supercellular mode eventually
  transitioning to a more linear mode by late afternoon/early evening.
  Strengthening low/mid-level southwesterly flow and steep 0-3km lapse
  rates should favor several swaths of strong/damaging winds across
  the upgraded area this evening.

  3) The 45-percent hail/sig hail delineation has been removed from
  portions of southern Alabama/Georgia and adjacent portions of the
  extreme northern part of the Florida Panhandle. Ongoing convection
  and cloud cover over this region cast doubt upon the potential for
  vigorous convective re-development in its wake. Additionally,
  veering low-level flow and weaker forcing for ascent (than points
  farther north) also yield high uncertainty regarding the potential
  for this re-development. As such, the associated moderate risk has
  been removed from this area.

  ..Picca.. 04/05/2017

  .PREV DISCUSSION... /ISSUED 1129 AM CDT Wed Apr 05 2017/

  ...Portions of the Southeast States to the Ohio Valley region and
  the Mid-Atlantic...
  Ongoing semi-discrete supercells and supercell clusters are
  developing northeastward from parts of the central/eastern Gulf
  Coast into southern GA. This activity resides well ahead of a
  shortwave trough across the South-Central States and is evolving
  within a broad, moistening open warm sector. With observational data
  suggesting dewpoints in the lower 70s developing northward ahead of
  this activity, supporting MLCAPE around 2000-3000 J/kg aided by
  warm-sector insolation steepening low-level lapse rates beneath a
  residual EML plume, and given the ongoing semi-discrete nature to
  rotating updrafts developing as far south as the central Gulf Coast
  vicinity, there is increasing confidence that long-track supercells
  will be likely. Furthermore, with maturing midlevel mesocyclones
  already evident, and low-level SRH around 200-300 m2/s2 aiding the
  development of low-level mesocyclones amid the increasing low-level
  theta-e, confidence has increased in higher coverage of tornado
  potential -- including significant tornado potential -- across the
  now-upgraded High Risk area. This activity will spread across the
  High Risk area into the evening hours, as vertical wind profiles
  further strengthen with the approaching midlevel trough and 700-mb
  flow increasing over 50 kt. Observational trends and previous model
  guidance are the primary supporters of this High Risk upgrade, as
  opposed to the most recent model guidance which suggests a dry bias
  in thermodynamic profiles -- Reference Mesoscale Discussion 440.
  Outflow from ongoing convection from north GA to western SC serves
  as a northern bound to the greatest severe potential.

  Furthermore, confidence has increased that substantial severe risk
  including tornado potential will develop through parts of the
  Mid-Atlantic region into the overnight hours amid strong low-level
  and deep shear, and a moistening boundary layer. As a result, severe
  probabilities have been increased across parts of the Mid-Atlantic.
  Also, severe storms are expected to spread across parts of the Gulf
  Coast vicinity into the evening/overnight hours -- affecting parts
  of north/central FL with tornado potential.

  Farther to the west, a somewhat separate area of severe storm
  development will be likely from parts of the Ohio Valley region to
  the Tennessee Valley and vicinity in association with the primary
  midlevel vorticity maximum and related low-level baroclinic zone
  this afternoon. Strong low-level SRH in the destabilizing warm
  sector -- enhanced near the surface low tracking from parts of IL
  into OH -- will support organized, rotating updrafts. All severe
  hazards -- including significant hail and tornadoes -- will be
  possible from this afternoon into the evening.

  CLICK TO GET WUUS01 PTSDY1 PRODUCT

  NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
  CURRENT UTC TIME: 2049Z (4:49PM), RELOAD THIS PAGE TO UPDATE THE TIME

gomexwx wrote:Maybe it will send some rain your way San...

I'm between .1 and .5 in the QPF.... Not much, but I'll take what I can get Gomey!

Oh Noooooo!!!

sangria wrote:

JRnOldsmar wrote:

That's my girl!!
From Sis:
Got 3 weather alerts going off at once here. Radar has warning box just north of us for the moment and the closet is ready if I need it.

Good for her!!  Brad Panovich actually did a FB stream today about how to prepare, including having the closet ready.

Thanks for the models.
After seeing the updates, family in Jax will not be surprised either. They're the ones that hardly pay attention, until they hear from me.

gomexwx wrote:

Oh Noooooo!!!

LOL Gomey!    I got your explosion!!



NWS Storm Prediction Center Norman OK
  0329 PM CDT Wed Apr 05 2017

  Areas affected...Portions of southwest AL...southeast MS...western
  FL Panhandle

  Concerning...Severe potential...Watch possible

  Valid 052029Z - 052300Z

  Probability of Watch Issuance...40 percent

  SUMMARY...The area is being monitored for some potential of
  severe-thunderstorm development this afternoon and early evening.
  While not likely, it is possible that a watch could be issued.

  DISCUSSION...Towering cumulus development continues along a weak
  front analyzed from southeast MS into southeast LA. The air mass
  east of this boundary is only modestly capped based on the 18Z
  Slidell sounding, which indicates MLCAPE around 1500-2500 J/kg aided
  by the inland extension of relatively rich Gulf moisture. Areas of
  surface heating west of more widespread convection over GA into the
  FL Panhandle will continue supporting destabilization, while the
  southern extent of a shortwave trough approaches from the west.
  Stronger deep ascent will reside well to the north of the Discussion
  area, and low-level convergence remains weak per observational data.
  These factors cast considerable doubt regarding the sustenance of
  deep convection. Regardless, with 50-60 kt of effective shear
  conditionally supporting organized convective structures/supercells,
  a conditional severe risk could exist into the early evening.
  However, confidence in sufficient severe coverage is quite limited
  at present.

Bump.  That's all I've got.  Stay safe/be safe! Especially for the folks further north.