*Possible Widespread Severe 23rd/24th*
+9
Jed33
Stovepipe
Vanster67
Math/Met
Reb
Dyersburg Weather
tennessee storm09
Eric
Toot
13 posters
Page 2 of 3
Page 2 of 3 • 1, 2, 3
Re: *Possible Widespread Severe 23rd/24th*
Man its gonna get juicy today...already near 60 in the southern valley
Re: *Possible Widespread Severe 23rd/24th*
Last night was so weird. It was raining, nothing major. And all of a sudden there was a thunder clap so loud it hurt my ears. It literally rocked our house. We both jumped like we had been shot. I ran outside (stupid thing to do, now I think about it..lol) and checked to see if our house was o.k. I have never in my life heard such thunder, but it only did it once. Freaky.
Re: *Possible Widespread Severe 23rd/24th*
There's no mechanism to break the cap today it looks like. Most models don't initiate convection until well after dark.
Models have been especially terrible of late. Anyone else notice?
Models have been especially terrible of late. Anyone else notice?
jmundie- Winter Specialist
- Posts : 743
Join date : 2011-12-19
Re: *Possible Widespread Severe 23rd/24th*
jmundie wrote:There's no mechanism to break the cap today it looks like.
What does that mean? Cap?
Re: *Possible Widespread Severe 23rd/24th*
jmundie wrote:There's no mechanism to break the cap today it looks like. Most models don't initiate convection until well after dark.
Models have been especially terrible of late. Anyone else notice?
This is just a sick, sick sounding....
Eric- Severe Wx Specialist
- Posts : 100
Join date : 2012-02-19
Re: *Possible Widespread Severe 23rd/24th*
When there is a layer of warmer air above cooler air at the surface. The warmer air acts as a cap for convection that wants to occur, storms explode from the surface up into the atmosphere, the cap prevents the storms from growing very tall. You do need a cap to keep convection from just popping up all over the place, if you want severe thunderstorms, but if the cap is too strong, no storms can break it, and you don't get anything.
Eric can explain better - or this article
http://www.downunderchase.com/storminfo/stormguide/guide07.html
Eric can explain better - or this article
http://www.downunderchase.com/storminfo/stormguide/guide07.html
jmundie- Winter Specialist
- Posts : 743
Join date : 2011-12-19
Re: *Possible Widespread Severe 23rd/24th*
Homemommy wrote:jmundie wrote:There's no mechanism to break the cap today it looks like.
What does that mean? Cap?
It's a temperature inversion above the surface that acts as a "lid" to keep updrafts - i.e. convection - from forming. If you look at the skew-T that I just posted, the red line is the temperature. Notice how it rises slightly to the left then BOOM it takes a huge hit to the right, that's a temperature inversion. Temps normally cool as they rise, when they don't, you get an inversion.
Eric- Severe Wx Specialist
- Posts : 100
Join date : 2012-02-19
Re: *Possible Widespread Severe 23rd/24th*
Eric wrote:jmundie wrote:There's no mechanism to break the cap today it looks like. Most models don't initiate convection until well after dark.
Models have been especially terrible of late. Anyone else notice?
This is just a sick, sick sounding....
Yeah - I was going to pull one of the RUC soundings to try and show the cap, but the last 12 hour run, looked like a loaded gun sounding.
Geez - I guess you do need a decent cap to get the worst severe weather - if it can break tonight, it could get rough in a hurry.
jmundie- Winter Specialist
- Posts : 743
Join date : 2011-12-19
Re: *Possible Widespread Severe 23rd/24th*
jmundie wrote:Eric wrote:jmundie wrote:There's no mechanism to break the cap today it looks like. Most models don't initiate convection until well after dark.
Models have been especially terrible of late. Anyone else notice?
This is just a sick, sick sounding....
Yeah - I was going to pull one of the RUC soundings to try and show the cap, but the last 12 hour run, looked like a loaded gun sounding.
Geez - I guess you do need a decent cap to get the worst severe weather - if it can break tonight, it could get rough in a hurry.
Dang sure looks like a "loaded gun" sounding...but like you, I just can't find anything on the near-term modeling that could/would break that sucker. Yet.
Eric- Severe Wx Specialist
- Posts : 100
Join date : 2012-02-19
Re: *Possible Widespread Severe 23rd/24th*
Just to add to the already good responses regarding the cap. There is also a process called Potential Instability. This is also referred to as convective instability. Basically, a cap doesn’t necessarily imply that the inversion layer will remain stable. It can become unstable with the help of a lifting mechanism. Because the wet-bulb lapse rate in that layer is less than the moist adiabatic lapse rate, the cap layer is considered Potentially Unstable. If this layer was lifted for any reason, then the top of the layer would cool quicker than the bottom part of the layer. This is the result of the bottom part of the layer reaching saturation quicker because the dew point depression is smaller at the lower levels of the inversion. This would effectively increase the lapse rate of the inversion layer and make it unstable. It is kind of hard to explain, but I hope that makes sense.
Math/Met- Meteorologist
- Posts : 226
Join date : 2011-12-05
Re: *Possible Widespread Severe 23rd/24th*
SPC Update:
...KY SOUTH TO THE TN VALLEY AND EVENTUALLY ACROSS THE APPALACHIAN
CREST...
BROKEN QUASI-LINEAR SQUALL LINE IS ANTICIPATED AHEAD OF THE COLD
FRONT MOVING ACROSS THESE AREAS LATE. WHILE MODEST FORCING ALONG THE
FRONT SHOULD FORCE THIS CONVECTION...TIME OF DAY AND LACK OF GREATER
INSTABILITY WOULD SUGGEST LIMITED SEVERE POTENTIAL WITH A FEW WIDELY
SCATTERED WIND/HAIL EVENTS POSSIBLE THROUGH THE REMAINDER OF THE
PERIOD.
Eric- Severe Wx Specialist
- Posts : 100
Join date : 2012-02-19
Re: *Possible Widespread Severe 23rd/24th*
Thanks for the explanations. When I heard "Cap" it was like, WTF? but I understand better now.
Re: *Possible Widespread Severe 23rd/24th*
jmundie wrote:There's no mechanism to break the cap today it looks like. Most models don't initiate convection until well after dark.
Models have been especially terrible of late. Anyone else notice?
It seems to my eye that the HRRR just isn't picking up on much for tonight's storm. Not even a real squall line, just popcorny stuff. The RUC is getting juicier though. Of course I'm just looking at the reflectivity.
Re: *Possible Widespread Severe 23rd/24th*
I don't know what it's gonna do tonight, but the weather right now is gorgeous. As much as I love snow, this is pretty nice. Starting to get the fever.
Re: *Possible Widespread Severe 23rd/24th*
Its warm out there and very windy but no clouds earlyer now I see a few but like not many and they fall apart after a few minutes it seems.
skillsweather- Banned
- Posts : 313
Join date : 2011-12-06
Age : 32
Location : tennessee Wilson county Ne Corner
Re: *Possible Widespread Severe 23rd/24th*
Seeing how I will apparently never learn how to post 'text" (LOL) I will just type what I read NWS. Latest update moved us from a 15% damaging wind threat to 30%. Great day tho. Even if I slept thru most of it
Vanster67- Admin
- Posts : 629
Join date : 2011-12-08
Age : 57
Location : Monterey, TN
Re: *Possible Widespread Severe 23rd/24th*
what a wasted day of warm temps here in west tn for the month of february... just no instability what so ever... at 2 oclock this afternoon... i had a barometer reading of 29.29, and not a clud in the sky... that folks is a pretty damn low pressure reading... i m ready for the next system... maybe you folks in east tn. still will muster up something after dark.
tennessee storm09- Severe Wx Specialist
- Posts : 1304
Join date : 2011-12-05
Age : 61
Location : jackson,tennessee(home of 3 ef4 tornadoes since 1999)
Re: *Possible Widespread Severe 23rd/24th*
Looks like the cap is breaking about now...not really expecting any tornados due to Meh instability and the dynamics look to be pretty far north of here...I do think a nice hailer remains possible in middle/east TN
Re: *Possible Widespread Severe 23rd/24th*
Toot wrote:Looks like the cap is breaking about now...not really expecting any tornados due to Meh instability and the dynamics look to be pretty far north of here...I do think a nice hailer remains possible in middle/east TN
Re: *Possible Widespread Severe 23rd/24th*
What setting is best on the dual pol radar for hail?
(Using RadarScope)
(Using RadarScope)
Re: *Possible Widespread Severe 23rd/24th*
Toot wrote:I know nothing about radarscope.
I was pretty vague, sorry. The choices are:
Hydrometeor Classification
Differential Phase Tilt
Correlation Coefficient
Defferential Reflectivity
Which of those would best show areas of hail?
Page 2 of 3 • 1, 2, 3
Similar topics
» Severe Nov 17
» March Severe
» May Severe Weather
» Severe wx basics
» Severe Storms possible for day 4
» March Severe
» May Severe Weather
» Severe wx basics
» Severe Storms possible for day 4
Page 2 of 3
Permissions in this forum:
You cannot reply to topics in this forum