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April 2024 Weather Video of the Month Post your nominations now!
November 19-21st severe threat
- Thread starter UncleJuJu98
- Start date
KevinH
Member
Do you have the TOR probs for the same time period too?
Attachments
KevinH
Member
2% (for now)…..k
Thanks!
Thanks!
JPWX
Member
So here's my idea of what SPC might do in my opinion.
Expansion of Slight Risk north of Tupelo and east into more of western Alabama with a broad Enhanced Risk (maybe not that big but still)
Expansion of the 5% TOR probability north of Tupelo and east into western Alabama with a 10% SIG TOR hatch centered over central/southern MS.
I am concerned about a greater threat across southern North MS counties. Monroe County, MS has been a hotspot for tornado activity this year for some reason and so there's my reason for being concerned.
If you go back and look, the EF-1 tornado in Muldon, MS on January 12th occurred on a Level 2 Slight Risk with 5% TOR Probability. The EF-1 tornado 2 miles west of Smithville, MS on February 16th occurred on a Level 3 Enhanced Risk with a 10% SIG TOR Hatch. The EF-3 Amory, MS tornado on March 24th occurred on a Level 4 Moderate Risk (but Northeast MS and Monroe County remained in a Level 3 Enhanced Risk) with a 10% SIG TOR Hatch. Below I'm just talking about the setup in Monroe County, not overall setup.
January 12th setup: CAPE was just around 1000 with effective SRH over 200 with dewpoints in the mid-60s.
February 16th setup: CAPE was just around 300 with effective SRH 250-400 with dewpoints in the mid-60s to near 70.
March 24th setup: CAPE was just around 1000 with effective SRH 400-500 with dewpoints in the mid to upper 60s.
Expansion of Slight Risk north of Tupelo and east into more of western Alabama with a broad Enhanced Risk (maybe not that big but still)
Expansion of the 5% TOR probability north of Tupelo and east into western Alabama with a 10% SIG TOR hatch centered over central/southern MS.
I am concerned about a greater threat across southern North MS counties. Monroe County, MS has been a hotspot for tornado activity this year for some reason and so there's my reason for being concerned.
If you go back and look, the EF-1 tornado in Muldon, MS on January 12th occurred on a Level 2 Slight Risk with 5% TOR Probability. The EF-1 tornado 2 miles west of Smithville, MS on February 16th occurred on a Level 3 Enhanced Risk with a 10% SIG TOR Hatch. The EF-3 Amory, MS tornado on March 24th occurred on a Level 4 Moderate Risk (but Northeast MS and Monroe County remained in a Level 3 Enhanced Risk) with a 10% SIG TOR Hatch. Below I'm just talking about the setup in Monroe County, not overall setup.
January 12th setup: CAPE was just around 1000 with effective SRH over 200 with dewpoints in the mid-60s.
February 16th setup: CAPE was just around 300 with effective SRH 250-400 with dewpoints in the mid-60s to near 70.
March 24th setup: CAPE was just around 1000 with effective SRH 400-500 with dewpoints in the mid to upper 60s.
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They just made it official
KevinH
Member
It’s SPC official now… ENH
KevinH
Member
Love when you post stuff like this lol
- Thread starter
- #30
That's a rather large hatched 10% I'm impressed.
- Thread starter
- #31
The WRF runs are dangerous.
It's going to be a long day in the southeast tommorow.
999-1001 mb low with 1000+ Sbcape. And a really good synoptic look.
It's going to be a long day in the southeast tommorow.
999-1001 mb low with 1000+ Sbcape. And a really good synoptic look.
Last edited:
JPWX
Member
From SPC Day 2 Discussion:
"Significant mass response is expected after 21Z which will lead to a
strengthening low-level jet and low-level shear. This timing will
correspond well to peak diurnal heating and supercell intensity. As
hodographs elongate between 21Z and 00Z, the low-level wind profile
will become increasingly favorable with nearly pure streamwise
vorticity in the lowest 750m of most forecast soundings. Most CAM
guidance shows mature supercells in the region at this time which
would support tornado potential, some potentially strong.
Diurnal thunderstorm activity is expected to become more linear
through the evening with an increasing damaging wind threat.
However, as the low-level jet intensifies, increasing isentropic
ascent may be sufficient for additional warm-sector supercell
development across Mississippi during the evening and into the
overnight hours. The less favorable diurnal timing casts some doubt
on the intensity of these supercells, but the wind profile will be
extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong
supercells which develop in this region after dark would pose some
strong tornado threat."
"Significant mass response is expected after 21Z which will lead to a
strengthening low-level jet and low-level shear. This timing will
correspond well to peak diurnal heating and supercell intensity. As
hodographs elongate between 21Z and 00Z, the low-level wind profile
will become increasingly favorable with nearly pure streamwise
vorticity in the lowest 750m of most forecast soundings. Most CAM
guidance shows mature supercells in the region at this time which
would support tornado potential, some potentially strong.
Diurnal thunderstorm activity is expected to become more linear
through the evening with an increasing damaging wind threat.
However, as the low-level jet intensifies, increasing isentropic
ascent may be sufficient for additional warm-sector supercell
development across Mississippi during the evening and into the
overnight hours. The less favorable diurnal timing casts some doubt
on the intensity of these supercells, but the wind profile will be
extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong
supercells which develop in this region after dark would pose some
strong tornado threat."
Attachments
- Thread starter
- #33
Your gunna have a fun day tommorow in Mississippi JP. Stay safe. I think I may start my day early so I can see what happens. Here's a link to treys new video for tommorow
JPWX
Member
Yes. Unfortunately, as always, it'll be overnight for me.
Pass the caffeine...
JPWX
Member
Exactly!
KevinH
Member
- Thread starter
- #38
Pretty juicy atmosphere for the enhanced threat zone. Looking at 1500-1800 sbcape in a decent bit of the area that wants to about 1000 in the evening and night and widespread upper 60s and low 70s dew points. 
- Thread starter
- #39
Impressive simulated radar. https://x.com/weathertrackus/status/1726368495523258554?s=20
KevinH
Member
And the follow up post (with pics):
The synoptic setup is almost in a "perfect" (not that that's any good for folks in the area) position.
The trough is bringing enough ascent for robust thunderstorm develop, but not too much (like the HRRR) to make everything messy.
Strong LLJ as well which results in intense low-level shear.
Main drawback here is the modest instability. Now, 750 J/kg can still support supercells & tornadoes, but could end up causing them to be shorter-lived. However it's important to note it's still possible we end up with more (or even less) instability than modeled.
Overall, models have been trending the more concerning way today compared to yesterday.
