Absolute Vorticity

BG does bring up some good points. With at least some of this system being the remnants of that hurricane that hit Mexico, the PWs will be higher than normal (see below image) so rains will be heavier in cells that form which could cause some minor flood issues. Good news is - it has been dry and the ground is not saturated plus the progressive nature of the storm shouldn't cause any major issues there.

Another factor to consider, especially if we see sunshine and the instability is a bit higher than progged is with the twisting in the atmosphere, a spin-up tornado is definitely possible and SPC has that covered nicely with their 5% contour.

Great post, Mike! I don't really have much more to add until more data comes in. But I still think the key is prefrontal junk to lower the instability or does it stay mainly quiet on Friday until we get closer to sunset. That is what's going to make it or break it to me.

With our Oct heat wave coming to an end Saturday , looks like the first half will end up close to +10 above normal . Good riddance

12z NAM coming in showing showers around midday to early afternoon. If this occurs, IMO, the severe threat should be reduced. NAM has the low deepening as it moves thru but the low is right over us so the severe threat would mainly be to our south with a track like that.

12Z GFS has a better low track thru Central IN to Lake Erie, it also shows showers possible at anytime from about midday to early afternoon on. IMO too much prefrontal activity that should limit the CAPE for the evening action. I'm just not too hip on this to be honest. I still think the marginal risk is fine versus the slight risk. Of course models are models and the reality of it will be tomorrow when we actually can see radar and visible satellite pics. Then, we can make a good determination on this system. From this distance, just going by the data, strong storms yes, severe should be very isolated. Just my opinion on this and you guys are free to post your thoughts if you have not already.

My thoughts are why does it have to be a Friday night.

Bgoney wrote: ↑Thu Oct 14, 2021 10:29 am With our Oct heat wave coming to an end Saturday , looks like the first half will end up close to +10 above normal . Good riddance

This is probably in the top 10, if not top 5 warmest starts to October

tron777 wrote: ↑Thu Oct 14, 2021 12:21 pm 12Z GFS has a better low track thru Central IN to Lake Erie, it also shows showers possible at anytime from about midday to early afternoon on. IMO too much prefrontal activity that should limit the CAPE for the evening action. I'm just not too hip on this to be honest. I still think the marginal risk is fine versus the slight risk. Of course models are models and the reality of it will be tomorrow when we actually can see radar and visible satellite pics. Then, we can make a good determination on this system. From this distance, just going by the data, strong storms yes, severe should be very isolated. Just my opinion on this and you guys are free to post your thoughts if you have not already.

Very probable the SLGT risk will be trimmed to the south of us with marginal for AV land for tomorrow in future updates. We shall see!

Ha Ha - well go figure. They actually extended the SLGT risk into NE Ohio for tomorrow. LOL

Euro is in agreement. They must be seeing something that i'm not seeing I guess. We'll see how tomorrow unfolds and go from there. It's all we can do.

Trentonwx06 wrote: ↑Thu Oct 14, 2021 1:00 pm My thoughts are why does it have to be a Friday night.

Yeah... severe or not, it's not going to be fun for high school football that is for sure. Could see some delays of course with lightning.

Bgoney wrote: ↑Thu Oct 14, 2021 1:22 pm

Bgoney wrote: ↑Thu Oct 14, 2021 10:29 am With our Oct heat wave coming to an end Saturday , looks like the first half will end up close to +10 above normal . Good riddance

This is probably in the top 10, if not top 5 warmest starts to October

Here are the Top Ten warmest Rocktobers for CVG - This is for the entire month.


Currently, thru 10/13 we are at 69.6 This will of course lower starting on Sat. Depends on how cold we get to see where the month ends up. I'd say right now, this maybe the warmest start to Rocktober, ever based on how the monthly avg's turned out.

Very nice AFD from the boys pretty much replicates our thinking on here regarding tomorrow....

Scattered showers and perhaps a few rumbles of thunder are
expected Friday morning as a surface wave traverses through
east-central IN into northwest OH. CAMs have period in the late
morning into the early afternoon hours where a lull in pcpn is
expected in our CWA. This period will play an impactful role
into how the next round of showers and storms will evolve in the
afternoon/evening hours.

The biggest concern for severe weather potential will be in a
window from about 3PM-9PM in our CWA Friday. However, the severe
potential will be very conditional upon the amount of instability
available in the environment for the storms to work with.
Ensembles from the SREF and deterministic model runs do show
MLCAPE increasing to around 500-1000 J/kg by the afternoon,
which is more on the marginal side. The amount of morning
showers and lingering cloud coverage will ultimately determine
how much instability will build for the afternoon. Along with
the instability, low and mid-level lapse rates don't appear to
be the most favorable either - generally around 6-7C/km.

What does appear to be more favorable are the kinematics in the
environment. Sfc-1km shear near 20kts and sfc-3km shear near 30
kts are conducive for longer-lived, organized storms. Additionally,
there is some concern with the surface wave moving through
western/northwestern OH as this low could allow for some
additional backing of the surface winds and ultimately provide
better directional shear values for rotation. SRH values above
100 in the sfc-1km layer highlight some of this low-level
rotation that could be present within the line of storms. As
such, the risk for a weak tornado still remains possible based
on the shear profiles. Damaging straight-line winds do still
remain the primary threat, but confidence right now in severe
weather is medium to low as it will all be very conditional on
the improvement of the low and mid-level thermodynamics.

Threat for severe weather potential diminishes by 8-10 PM in our
eastern CWA. Periods of showers and a few thunderstorms will
continue to move through our fa Friday night as the cold front
slowly moves through. There could be a few isolated locations
where heavy rainfall could be a concern, but overall, this
system will be fairly progressive, so training storms would
likely be needed to cause any flooding concerns.

tron777 wrote: ↑Thu Oct 14, 2021 3:30 pm

Bgoney wrote: ↑Thu Oct 14, 2021 1:22 pm

Bgoney wrote: ↑Thu Oct 14, 2021 10:29 am With our Oct heat wave coming to an end Saturday , looks like the first half will end up close to +10 above normal . Good riddance

This is probably in the top 10, if not top 5 warmest starts to October

Here are the Top Ten warmest Rocktobers for CVG - This is for the entire month.


WarmRocktober.png


Currently, thru 10/13 we are at 69.6 This will of course lower starting on Sat. Depends on how cold we get to see where the month ends up. I'd say right now, this maybe the warmest start to Rocktober, ever based on how the monthly avg's turned out.

Here you go Les, we're not just blowing smoke

No doubt guys its been very warm and rather wet for October. Grass looks like mid-May and the trees are having a hard time changing colors. That will change quickly over the next 2 weeks.

So far we hit 78 for the high so if we don't hit 80 then lets wait until next April. Lets hope so!!!

Bgoney wrote: ↑Thu Oct 14, 2021 4:18 pm

tron777 wrote: ↑Thu Oct 14, 2021 3:30 pm

Bgoney wrote: ↑Thu Oct 14, 2021 1:22 pm

Bgoney wrote: ↑Thu Oct 14, 2021 10:29 am With our Oct heat wave coming to an end Saturday , looks like the first half will end up close to +10 above normal . Good riddance

This is probably in the top 10, if not top 5 warmest starts to October

Here are the Top Ten warmest Rocktobers for CVG - This is for the entire month.


WarmRocktober.png


Currently, thru 10/13 we are at 69.6 This will of course lower starting on Sat. Depends on how cold we get to see where the month ends up. I'd say right now, this maybe the warmest start to Rocktober, ever based on how the monthly avg's turned out.

Here you go Les, we're not just blowing smoke

rank1.png

Awesome! Thanks for finding this. Def confirms what we've been posting.

tpweather wrote: ↑Thu Oct 14, 2021 4:45 pm So far we hit 78 for the high so if we don't hit 80 then lets wait until next April. Lets hope so!!!

I hit 80 today! I agree, should be the last one for the season.

Thank you also Mike for posting ILN's AFD earlier. It absolutely confirms that our thinking is on the right track. Clouds / prefrontal convection should limit the severe threat. If we do not see that then of course the threat goes up. The period between 12pm and 4pm will be telling to see how much CAPE we can get.

tron777 wrote: ↑Thu Oct 14, 2021 4:51 pm

tpweather wrote: ↑Thu Oct 14, 2021 4:45 pm So far we hit 78 for the high so if we don't hit 80 then lets wait until next April. Lets hope so!!!

I hit 80 today! I agree, should be the last one for the season.

CVG hit 80 as well per the 5pm climate report.

It felt toasty out there today. We tied a record of 86 here today. Geez Louise.

So 80 at both CVG and DAY and a Record 86 at CMH for the last 80s of the year.

Yesterday evening just had a ground wetter here in Greenville, too.

On the noon wx segment via WHIO7 met Dontae Jones mentioned a window of 9 PM to midnight on Fri as having a strong or severe? t-storm. Like was mentioned here earlier will be dependent on how much the atmosphere is worked over Fri morning and afternoon and what ingredients are in place ahead of the front.

Currently 77 here.

The rest of Rocktober as a whole looks to be avg to below avg in temps. A couple of days next week will be a few degrees above avg (L70s) but those insane +10 to 15 departures are done. In CMH's case over +20 since they broke that record!

Made it to 82 here

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