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The newest 00z EURO run looks more similar to the 00z GFS.
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Bingo , and you are correct . Now a day 5 large 30 percent areaModels don't differ on the instability axis and extreme shear axis being in conjunction with one another. I anticipate a 30 risk area in the new Day 5.
That was the Canton, TX EF4, for those who don't recall that dateLast 30% Enhanced for both Day 4 and 5 was April 29th, 2017.
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 180901
SPC AC 180901
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0401 AM CDT Fri Mar 18 2022
Valid 211200Z - 261200Z
...DISCUSSION...
Medium-range global model output -- both deterministic and ensemble
-- continues to indicate a multi-day severe weather event that will
progress eastward from the southern Plains Day 4/Monday to the
Southeast Day 6/Wednesday. The risk will stem from an upper
trough/low that will emerge from the western U.S. into the central
and southern Plains Monday. On Tuesday, models forecast a large
upper cyclone moving slowly across the Plains toward the Mid
Mississippi Valley, and then gradually elongating in a positively
tilted manner as it slowly impinges on the Midwest.
As a surface low develops over the northwestern Texas vicinity on
Monday in conjunction with the advance of an upper low, low-level
southeasterlies ahead of the cold front will advect Gulf moisture
across southeastern and into eastern Texas. As the initially stable
boundary layer moistens, surface-based CAPE is forecast to gradually
increase, supporting thunderstorm development which should persist
through the evening and into the overnight. With strong
southwesterly mid-level flow spreading atop the low-level
southerlies/southeasterlies, shear will support organized/supercell
storms, with an all-hazards severe risk including a few tornadoes
expected.
As the cold front advances from East Texas late Monday and early
Tuesday, toward -- and eventually across -- the lower Mississippi
Valley, a similar overall pre-frontal thermodynamic and kinematic
environment is expected as existed Monday, farther west. As the
moistening low-level airmass contributes to ample mixed-layer CAPE,
and strong/veering flow with height overlaps the instability,
severe/supercell storms are again expected. Potential for a few
tornadoes remains evident, along with hail/wind risk, centered over
Mississippi and extending into Alabama, particularly into the second
half of the period.
Risk should spread eastward across Alabama into Georgia Wednesday,
though with stronger ascent becoming somewhat removed from the more
favorable thermodynamic environment, overall severe risk may be a
bit lower than prior days. Still, potential for severe weather --
including supercells -- still appears a reasonable expectation, and
thus will maintain 15% probability into Georgia and the Florida
Panhandle.
As the front nears, and then likely reaches, the southern Atlantic
Coast rather early Thursday, degree of risk appears at this point to
likely remain limited before the boundary moves offshore. This
should mark the end of this multi-day severe-weather episode, with
Friday severe potential appearing minimal at best, at this time.
..Goss.. 03/18/2022
That is all specifically for the Tuesday portion of the risk. I have a not-so-good feeling about the Monday threat back in Texas, since that area will be closer to the EML source region with steep lapse rates and drier air aloft, and having a sharp southeast flow there actually sets up low-level advection right from that reservoir of low/mid 70 dewpoints in the northwest Gulf. SE surface winds in Texas ≠ same outcome as SE surface winds in Mississippi and Alabama.
...SEVERE WEATHER OUTBREAK POSSIBLE ON D4/TUE...
...DISCUSSION...
Latest deterministic and ensemble runs of the medium-range global
models continue to depict likelihood of a continuation of
potentially substantial severe-weather event across the central Gulf
Coast states Tuesday and into Wednesday. This includes a reasonable
probability of a regional-type tornado outbreak centered over
central and southern Mississippi for Tuesday.
Nam being nam… it won’t be in its best till another 24. 36 hoursNow the 12Z NAM reaches Tuesday evening, and shows nil SBCAPE over a good chunk of SPC's 30% area despite dewpoints reaching the 60s...just bizarre.
Over on Southern WX: one analog brought up is the MS Delta outbreak of 1971 that killed 122 people. That happened in a La nina, too.