A plethora of questions

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K Johnson

EF0
Nov 24, 2007
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0
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Yorkshire, England
At last a forum I feel able to ask questions in! Thank you Tim!

I do feel a little bit stupid asking these questions, but seeing as I will expode if I don't get some answers soon - here goes....

1) Are there any female chasers who go out on their own for weeks at a time? How do they stay safe?

2) What exactly makes a good CAPE? What am I looking for on a good day?

3) What exactly makes a bad CAP? What am I looking for on a bad day?

4) I have an Olympus SP550UZ - and I am an utter novice photographer who specializes in taking particularly awful cloud photos. Are there standard settings that can be relied upon, or do all cameras react differently in different situations?

5) When there is a choice of storms to go after, how do you decide which is the one most likely to produce?

6) I think Chuck Doswell rocks. Ok thats not a question, but I don't feel able to express this in the more explosive threads - being a newbie an' all I don't want to tread on anyones toes. But I've only been on the chase scene 7 months and Chuck has already been very kind and funny and straight up with me and I dont like reading all the flaming against him.
I don't want any responses to this one - I just had to get it off my chest!

7) Is it not acceptable for a newbie with a severe lack of chasing knowledge to answer the 'chase buddies' forum posts? Obviously the gas and lodging costs would be split, but I wouldnt be able to contribute much to the knowledge!

Sorry for all the questions, and I hope this is the right place to post them. Feel free to delete / move / laugh as appropriate.

Kirstie
 
Dec 18, 2003
4,138
39
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Lubbock, TX
daviddrummond.com
At last a forum I feel able to ask questions in! Thank you Tim!

5) When there is a choice of storms to go after, how do you decide which is the one most likely to produce?

7) Is it not acceptable for a newbie with a severe lack of chasing knowledge to answer the 'chase buddies' forum posts? Obviously the gas and lodging costs would be split, but I wouldnt be able to contribute much to the knowledge!

Sorry for all the questions, and I hope this is the right place to post them. Feel free to delete / move / laugh as appropriate.

Kirstie
Since this area was my idea, I'll take the initiative here.

5) Just as a general simple answer that has always worked well for me when I follow it, and screwed me when I didn't. If your stuck with choosing the north or south storm, both are close enough to get on, go with the south one, other factors more or less equal. Example, a day with 3 or 4 supercells lined up along the dryline.

Reasoning is that often the southernmost storm has the better shot at the tornado and staying a supercell longer generally speaking, given that it has uninterrupted low level flow in to it not blocked by other storms, and not likely to get it's inflow air cooled down prematurely by the shade for another storms anvil, or even precip from another storm, such as one's north of the "tail end charlie" would.

In practice, I have almost always done well going with the southern storm, and missed out when I chose the one north of it. I have a little saying...when in doubt, go to the southern storm!

7) Sure you can post anywhere on the forum you have permissions. The idea for this area is to give newer chasers, or those interested in becoming chasers a place to feel comfortable asking any and all questions without feeling intimidated or overwhelmed as they might in the general forums. There is a HUGE amount of knowledge among chasers here. Sometimes we forget that the stuff that seems simple to us, was at one time a difficult thing to grasp when we started out. ;)
 

Jason Boggs

2) What exactly makes a good CAPE? What am I looking for on a good day?

3) What exactly makes a bad CAP? What am I looking for on a bad day?
CAPE-occurs when there is a lot of surface heating and high dewpoints. When all other things are equal, you will have more CAPE on a clear day than a cloud day. CAPE can also occur when there are steep lapse rates (cooling as you go up in the atmosphere. Here are some CAPE values to consider:

0-1000 MARGINALLY UNSTABLE
1000-2500 MODERATELY UNSTABLE
2500-3000 VERY UNSTABLE
3500+ EXTREMELY UNSTABLE

A cap is a layer of warm air a few thousand feet up in the atmosphere. Remember that you need an air parcel that is WARMER than the surrounding air to get storms. When a warm air parcel encounters a layer of warm air, the updraft essentially stops rising because it is no longer WARMER than the surrounding air. A storm day with no cap at all is not good. On a day like this, storms will form everywhere, and they will not be isolated. You need a storm day with a moderately strong cap and a good lifting mechanism. With this scenario, you will get isolated storms, and only the strongest updrafts will survive. Hope these answers help you out Kirstie.
 
Last edited by a moderator:
Dec 4, 2003
697
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Norman, OK
I'll take question number 1. Been chasing since 1995, most of it solo, and before I lived here, I'd take a three week vacation to the Plains for chasing. It boils down to situational awareness. I listen to my instincts, and if they're saying leave, I leave...doesn't matter if it's a chase situation or not. I've not been in any situations while chasing where I have felt physically threatened by another person. I don't know if that's because of my martial arts background, or if the culture is just different in the Plains, where it seems that women are treated with more respect. I know that another chaser has been in a few scary situations, but once again, it's a recognize danger and get the h*** out of Dodge response. I don't carry mace or pepper spray or any other weapons (with my luck, I'd hurt myself), I just keep a heads up on what's going on around me.Hope that sort of answers your question, Kirstie. Feel free to ask more, or PM if you'd like.Good luck and welcome to ST!!!!!
 

Shane Adams

2) What exactly makes a good CAPE? What am I looking for on a good day?
"CAPE" stands for "Convective Available Potential Energy", which basically means how much "umph" the atmosphere has to work with. Imagine the atmosphere as a can of soda. The sealed lid is the "cap" or the warm, dry layer of air in the 2000-7000ft range, and the soda is the warm, moist air at the surface trying to get out. If you simply open a can of soda, you get a small "pop" as the pressure inside is released. Now, if you shake that can, obviously you get a huge spray and a "pop" as the soda spews out all over. The amount of moisture and heat in the air at the surface dictates how much pressure or "umph" the atmosphere has to work with if the cap can be broken. Numbers-wise, anything over 1000 j/kg will support severe storms. Anything over 2000 j/kg would be considered "moderate" instability, and anything over 3000 j/kg would be "high" instability.

Just remember, the more humid and hot it is at the surface, the more CAPE will be created.


5) When there is a choice of storms to go after, how do you decide which is the one most likely to produce?
It's generally accepted that the southern-most storm is the one to go after, because, as David mentioned, it has the unobstructed warm surface inflow and isn't "fighting" for fuel like other storms further north would be. However, there are certain situations where the northern-most storm is the one to go after because it may be nearer any potential surface boundaries (such as a two/three storm situation inside the warm sector (east of the dryline/south of the warm front).

There are days when the dryline shear isn't as conducive to tornadoes as the warm front shear, so naturally any storms inside the warm sector would have a better chance at tornadoes closer to the warm front. I personally failed on May 5, 2001 when I opted for the southern storm, not realizing the northern storm was beginning to interact with a boundary. My southern storm never produced while the northern storm I abandoned did.
 

Mike Krzywonski

7) Is it not acceptable for a newbie with a severe lack of chasing knowledge to answer the 'chase buddies' forum posts? Obviously the gas and lodging costs would be split, but I wouldnt be able to contribute much to the knowledge!
I'm sure there are some who would be willing to have you team up w/ them as long as you're willing to split costs. You could also make your own post, & see who responds. Just make sure you team up w/ someone w/ experience.
 
Question...
"What exactly makes a good CAPE? What am I looking for on a good day?"

CAPE stands for Convective Available Potential Energy. It is a fancy term for instability. IMO a good way for beiginners to think of it is a speed limit on updrafts. Higher CAPE means faster/stronger updrafts because there is more instability (just in case instability means the air at the surface is going to be warmer than the surrounding air when it rises through the atmosphere).
What you are looking for is too big of a question to answer. In gereral the more CAPE the better. That doesn't necessarily mean you should always target the area with the highest CAPE when chasing because there are a lot of other things that are just as important when forecasting tornadoes. The amount of CAPE for a good chase day rises through the season. In March you may only get 1000j/kg on a good tornado day, in April you may average 1500j/kg, in May you may average 2500j/kg for good chase days, and June you may average 3000j/kg on a good tornado days.

Question...
"What exactly makes a bad CAP? What am I looking for on a bad day?"

As was said earlier, a cap is a warm air inversion above the surface. A good way to think of it is a lid on boiling water. The lid suppresses the energy from being released until it has built up so much that it breaks through the lid/cap.
As was also mentioned, you need a decent cap on good chase days to let the instability build at the surface throughout the day. It is a good thing so long as you will be able to break through the cap later in the day as you reach peak heating. Lift generated by approaching short waves can help to break the cap in several different ways, so some times even if surface temps alone aren't enough to break the cap it will still happen. It is a tricky thing to forecast since there is so much involved. A "bad cap" is one that is too strong to be broken because you are going to end up with blue skys and no surface based storms.

Question...
"When there is a choice of storms to go after, how do you decide which is the one most likely to produce?"

As was also mentioned earlier getting on the tail end storm is kind of a rule of thumb, but that really only applies over a small area. You don't want to neccessarily pick a target based on where the furthest South storm is going to be. It's not really being the furthest South that makes the storm better. You just want a storm with unimpeded inflow. Surface winds in the spring on severe weather days are usually southerly, so you want the storm to have a nice big open area to it's South so no other storms compete with or interfere with it's inflow. 60 miles is a big enough opening on the south side of a storm to have unimpeded inflow. So if there is another storm 60 miles to the South of the one I'm on with southerly surface winds, I'm not going to worry about it too much.
This rule of thumb is just for deciding which storm to get in a situation where you have multiple storms go up right in the area you targeted. Forecasting is going to tell you which area to target and that is beyond a huge topic.

Question...
"Is it not acceptable for a newbie with a severe lack of chasing knowledge to answer the 'chase buddies' forum posts? Obviously the gas and lodging costs would be split, but I wouldnt be able to contribute much to the knowledge!"

A lot of people are looking to split their costs and I'm sure of them don't care whether or not you bring experience to the table. It's perfectly acceptable to post on there. Just be open about your experience, how serious you are about chasing (distance you'll travel), and everything else that is relevant to a chase partner.