Week before Thanksgiving Severe thread

[DetectiveWX]

Discuss what could be a significant severe weather outbreak on 11/19-22 time frame.

 

[KevinH]

Discuss what could be a significant severe weather outbreak on 11/19-22 time frame.

Ok… how about we start with what you are seeing to suggest there could be an event during this time? lol

UPDATE: I just saw the posts from the 2024 thread.. WATCHING

 

[DetectiveWX]

Ok… how about we start with what you are seeing to suggest there could be an event during this time? lol

The severe thread page 153. Just tired from all the work and life balances. If models are correct, this could just as severe or moreso than Huntsville '89; 11/92; Veteran's Day '02; 11/17/13 and Thanksgiving '94, '01, '04 and '05..

 

[KevinH]

The severe thread page 153. Just tired from all the work and life balances. If models are correct, this could just as severe or moreso than Huntsville '89; 11/92 and Thanksgiving '94, '01 and '05..

Yeah I saw those comments after I got the email for this new thread and I don’t blame you for starting the thread. Not sure how I feel about the models picking things up THIS early…. In Dixie of all places.

I asked @MichelleH if she could move those comments here.

Would you mind putting the dates 11/19-11/22 in the title?

 

[MichelleH]

If another mod could move the posts over I would appreciate it. Just seeing the new thread and about to go to bed. My dog is in the hospital - again - and it's been a long day.

 

[TH2002]

If another mod could move the posts over I would appreciate it. Just seeing the new thread and about to go to bed. My dog is in the hospital - again - and it's been a long day.

We had to put down one of our dogs today. Her health had been steadily declining for weeks and by the end, she was unable to move. At 15 years old, at least she lived a good long life and isn't suffering anymore. I feel your pain.

 

[CheeselandSkies]

TBH the GFS frame posted by @Clancy in the 2024 thread doesn't show that favorable of a 500mb look for widespread significant severe weather, at least tornadoes. Flow in the exit region is way too meridional.

 

[MichelleH]

We had to put down one of our dogs today. Her health had been steadily declining for weeks and by the end, she was unable to move. At 15 years old, at least she lived a good long life and isn't suffering anymore. I feel your pain.

I am so, so sorry. We almost lost him a few years ago when he started having kidney failure, but his vet pulled him through it and he's a little flighter. About a month ago his liver numbers shot up and he developed a "sludge" in his gallbladder. That's getting better, but now his kidney levels are creeping back up and he won't eat. He's 9, but has went through a lot (he was a rescue) in those 9 years, so I don't want him to suffer, but....

 

[MichelleH]

SPC's thoughts this morning:

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CST Tue Nov 12 2024

Valid 151200Z - 201200Z

...DISCUSSION...
Guidance still generally suggests some organized severe potential
may evolve across the south-central Plains and vicinity early next
week, though uncertainty remains high regarding the timing and
intensity of embedded shortwave troughs and the details regarding
low-level moisture return and destabilization.

On D5/Saturday, a mid/upper-level shortwave trough is forecast to
emerge from the deep, positively tilted trough over the West and
move across the northern Plains, accompanied by a deepening surface
low. While severe potential appears minimal on Saturday, the
ejecting wave is forecast to initiate low-level moisture return into
the southern Plains, which will continue into D6/Sunday and
D7/Monday.

For D6/Sunday into D7/Monday, the most important feature related to
severe potential will be a shortwave trough that may briefly evolve
into a closed mid/upper-level low somewhere over the Southwest,
before ejecting east-northeastward. Recent runs of the deterministic
ECMWF/GFS are in relatively good agreement in depicting a negatively
tilted shortwave trough ejecting into the south-central Plains on
D7/Monday. However, spread among GEFS ensemble members remains
rather high regarding the timing and evolution of shortwaves into
early next week, while the ECMWF is less aggressive with low-level
moisture return, showing only very minimal destabilization in
advance of the ejecting shortwave trough on D7/Monday.

Given the uncertainties regarding both shortwave timing and
magnitude of moisture return/destabilization, confidence is too low
to delineate a 15 percent area over some portion of the
south-central Plains for D7/Monday, the day which seems to have the
greatest relative potential at this time. It remains possible that
some severe threat could emerge as soon as D6/Sunday, and/or
potentially persist into D8/Tuesday.

..Dean.. 11/12/2024

 

[Clancy]

@MichelleH Wishing your pup the best.
@TH2002 I'm so sorry to hear that; it's a kind of loss that hits hard no matter how ready you are.

TBH the GFS frame posted by @Clancy in the 2024 thread doesn't show that favorable of a 500mb look for widespread significant severe weather, at least tornadoes. Flow in the exit region is way too meridional.

Definitely not a tornado look - could see some potential for damaging winds. It did look a bit more potent in that department earlier in the run over the Plains. If there was to be tornado potential, it'd likely be highest there.

 

[Tanner]

TBH the GFS frame posted by @Clancy in the 2024 thread doesn't show that favorable of a 500mb look for widespread significant severe weather, at least tornadoes. Flow in the exit region is way too meridional.

Agreed.

 

[Tanner]

I'd be perfectly okay with no severe weather until prime time next spring (March-June). This year has been insane.

 

[KevinH]

DANGIT I thought I had email notifications for this thread enabled.

TIME TO CATCH UP

 

[MichelleH]

Snip from SPC extended outlook:

Some severe potential could evolve on D5/Sunday, especially later in
the period when the ejecting shortwave trough may begin to impinge
on richer moisture from southwest into central TX. An intensifying
low-level jet may support development of widespread convection from
late on D5/Sunday into D6/Monday, with a strongly forced band of
convection potentially moving east-northeastward across a larger
portion of the southern/central Plains.

Despite the very limited instability that is currently anticipated
across much of the region, the intense wind fields and strong ascent
associated with the ejecting shortwave trough (as depicted by the
GFS/ECMWF and some ensemble members) could support an organized
severe threat within a low-CAPE/high-shear regime. Uncertainty
remains regarding the most favorable corridor, with the GFS/ECMWF
favoring parts of the southern/central Plains, while some ensemble
members favor a zone farther east from the ArkLaTex into the mid MS
Valley.

...D7/Tuesday - D8/Wednesday...
Some severe potential could continue into D7/Tuesday into parts of
the Midwest and Ohio Valley, though there may be a tendency for
stronger deep-layer flow and ascent to become increasingly displaced
from sufficient moisture and instability.

 

[TH2002]

Snip from SPC extended outlook:

Some severe potential could evolve on D5/Sunday, especially later in
the period when the ejecting shortwave trough may begin to impinge
on richer moisture from southwest into central TX. An intensifying
low-level jet may support development of widespread convection from
late on D5/Sunday into D6/Monday, with a strongly forced band of
convection potentially moving east-northeastward across a larger
portion of the southern/central Plains.

Despite the very limited instability that is currently anticipated
across much of the region, the intense wind fields and strong ascent
associated with the ejecting shortwave trough (as depicted by the
GFS/ECMWF and some ensemble members) could support an organized
severe threat within a low-CAPE/high-shear regime. Uncertainty
remains regarding the most favorable corridor, with the GFS/ECMWF
favoring parts of the southern/central Plains, while some ensemble
members favor a zone farther east from the ArkLaTex into the mid MS
Valley.

...D7/Tuesday - D8/Wednesday...
Some severe potential could continue into D7/Tuesday into parts of
the Midwest and Ohio Valley, though there may be a tendency for
stronger deep-layer flow and ascent to become increasingly displaced
from sufficient moisture and instability.

Ever since March 2-3, 2020, high-shear low-CAPE setups make me very nervous. When they do take off they manage to produce localized but devastating outbreaks.

 

[JBishopwx]

.D4/Sunday into D5/Monday...
Extended-range guidance generally agrees that a mid/upper-level
shortwave trough/closed low will move eastward across parts of the
Southwest/northern Mexico through the day Sunday. This system will
eject northeastward as a negatively tilted shortwave trough Sunday
evening into Monday, accompanied by intense deep-layer flow fields
and significant surface cyclogenesis. Meanwhile, recent guidance has
trended toward somewhat richer low-level moisture return, with mid
to upper 60s F dewpoints spreading into parts of
southwest/central/north TX Sunday night into Monday, with at least
low 60s F dewpoints into parts of OK/KS.

Midlevel temperatures will remain relatively warm across the warm
sector, but there is greater confidence in at least modest
surface-based buoyancy (with MLCAPE of 500-1000 J/kg) developing
across parts of west/central TX Sunday night, accompanied by an
substantial increase in low-level and deep-layer shear. Isolated
severe storm potential cannot be ruled out by late afternoon into
early evening, but a notable increase in storm coverage is expected
Sunday night. Extensive convection may result in a tendency toward a
linear/QLCS mode, but intense deep-layer flow and increasing
low-level shear will support a threat of severe wind gusts along
with some tornado potential. A 15% area has been added for
D4/Sunday, where intensifying flow is forecast to overlap sufficient
instability amid as deep convection increases in coverage Sunday
night.

Some severe threat may persist from late D4/Sunday into at least
early D5/Monday, as the shortwave and attendant surface low continue
to eject northeastward. Uncertainty increases at this time range
regarding the northern and eastern extent of the severe threat on
D5/Monday, as richer low-level moisture potentially gets pinched off
from the stronger ascent from the ejecting shortwave trough, and
buoyancy becomes increasingly weak across the warm sector. Intense
wind fields will support some severe-wind and tornado potential
where convection can remain surface-based. There also may be some
potential for renewed storm development Monday afternoon in the
immediate vicinity of the ejecting shortwave and surface low across
the central Plains (as suggested in the 14/00Z ECMWF), though this
scenario remains quite uncertain.

A small 15% area has been included for D5/Monday, as a continuation
of the threat that begins late D4/Sunday. Depending on
destabilization trends during the day on Monday, probabilities may
eventually need to be expanded to the north and/or east of this
area.

...D6/Tuesday - D8/Thursday...
Some severe threat could linger on D6/Tuesday in the vicinity of the
MS Valley, though model spread increases substantially at this range
regarding the evolution of the upper-level pattern and occluding
cyclone over the northern Plains/upper Midwest. Otherwise, Tropical
Depression 19 has formed across the Caribbean, with the NHC forecast
track suggesting this system may eventually approach some portion of
the Gulf of Mexico. Uncertainty remains very high regarding any
severe threat with this system into mid/late next week.

 

[CheeselandSkies]

Seems like we've entered one of those patterns that's a little too active for its own good if you're looking for a good chase day. Lots of highly amplified troughs, but they all end up moisture starved because the Gulf doesn't have enough time to really juice up between them. Either that or instability is kept in check by warm midlevel temperatures for the time of year.

 

[Tanner]

Seems like we've entered one of those patterns that's a little too active for its own good if you're looking for a good chase day. Lots of highly amplified troughs, but they all end up moisture starved because the Gulf doesn't have enough time to really juice up between them. Either that or instability is kept in check by warm midlevel temperatures for the time of year.

I'm thinking threats closer to the gulf coast will be commonplace for the remainder of the year.

 

[KevinH]

Seems like we've entered one of those patterns that's a little too active for its own good if you're looking for a good chase day. Lots of highly amplified troughs, but they all end up moisture starved because the Gulf doesn't have enough time to really juice up between them. Either that or instability is kept in check by warm midlevel temperatures for the time of year.

And now you have jinxed us lol

Don’t underestimate the Gulf

 

[atrainguy]