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Chris the Weather Man wrote:LOL, Jeb, you want 1995-1996 Winter! I am sure everyone in the NE wants that winter back, but that winter was a winter that might happen for a long time.......
I would love to see the Halifax Blizzard of 2004 in the I-95 areas! Over 37 inches of snow fell in Halifax during the blizzard....
Chris the Weather Man wrote:LOL, Jeb, you want 1995-1996 Winter! I am sure everyone in the NE wants that winter back, but that winter was a winter that might happen for a long time.......
I would love to see the Halifax Blizzard of 2004 in the I-95 areas! Over 37 inches of snow fell in Halifax during the blizzard....
Jeb wrote:Chris the Weather Man wrote:LOL, Jeb, you want 1995-1996 Winter! I am sure everyone in the NE wants that winter back, but that winter was a winter that might happen for a long time.......
I would love to see the Halifax Blizzard of 2004 in the I-95 areas! Over 37 inches of snow fell in Halifax during the blizzard....
Yeah I have been wishing for and praying HARD for 36 inches of snow in one storm here in northern Virginia.......it would be heaven on earth for me! I'd be out there digging snow and then enjoying jebwalk after jebwalk after jebwalk!!! Last Sunday at Potomac Mills Mall where I conduct many of my jebwalks, I clocked 4 mph during a jebwalk. It took me just under an hour to walk 4.2 miles!
I'm ready for winter and snow jebwalks.............
-Arctic Jeb!!!!!!!!!!!!!!!!!!!!!!!!
Jeb wrote:I'd like to remind everyone here on the board, that even though I'm going hog-wild about winter, snow, ice jebwalks and messageboards, I still do not believe that Woodbridge, Virginia will get more than about 7 inches of snow this winter. I believe that this winter will be a HUGE one for the Midwest. The pattern is setting up that way. Midwesterners better have a well-tuned-up snowblower! Better yet, have TWO of 'em!! Don't even bother with snow shovels, you'll never have enough time to dig all that snow you're gonna get! You'll break your back!
I hope that I am very, very wrong. But I still only expect about two snowfalls of about three inches each in Woodbridge, Virginia all winter. It would sure be nice to be really wrong for once!
Man I wish I lived in Great Falls, Michigan! Because the 2004-2005 winter season is going to set all-time records in snowfall and cold!!
Enjoy it, King of Weather!! You lucky, lucky dog!! Enjoy all your snow, it's gonna pile up to the top of your windows there!! You'll have to tunnel out of your house by February, it's gonna be storm after storm after storm after storm!! It's ALREADY happening now! This is only the beginning!!
-SnowBlitz Jeb!!!!!!!!!!!!!!!!!!!!!!!
Jeb wrote:What on earth is CSI banding?
What is a deformation zone and why the heck don't I ever see one in northern Virginia lol?
What is a BUFKIT sounding?
I'm trying to think of as many of these met terms as I can that I always see tossed around when there is a BIG snow event in the East. Yeah I'll think of more.....
wxguy25 wrote:Jeb wrote:What on earth is CSI banding?
What is a deformation zone and why the heck don't I ever see one in northern Virginia lol?
What is a BUFKIT sounding?
I'm trying to think of as many of these met terms as I can that I always see tossed around when there is a BIG snow event in the East. Yeah I'll think of more.....
Ah CSI, one of the coolest wintertime MESOSCALE processes but The Issue of CSI (Conditional Symmetric Instability) is a complex one and even to some degree controversial. Ill try to put this into as simple of terms as possible.
CSI is a form of moist symmetric Instability which is characterized by the development of single and multiple clouds and precip bands in the vicinity of frontal zones associated with extratropical (Mid Latitude) cyclones.
The nature of the banding will be two dimensional /quasi-symmetric, the criteria needed for the development of the banding is met in the region where the bands are found and the bands align themselves parallel to the thicknesses field (thermal wind). Remember this is b/c thermal wind flows parallel to the thickness gradient. Bands move at the same speed the flow is moving which means the bands themselves have a propagation of zero.
It’s important to determine whether the criteria are met since similar bands can develop in response to ducted gravity waves, and Kelvin-Helmholtz instability. These types of instabilities produce wave like features in the atmosphere similar what you would see if you threw a rock in a lake.
What do you need atmospherically for CSI? First you need to be aware of the different types of instability and understand that the combination of Moisture, lift and instability is instrumental in the development of clouds and precipitation (for our purposes convection).
In the interest of saving time it’s pointless for me to go through all the different types of instability however I will go through the three MOST important ones for this situation, SI (Symmetric Instability) CSI (Conditional Symmetric instability) and PSI (potential Symmetric instability).
PSI / POTENTIAL Symmetric Instability:
Theta-e (Equivalent Potential Temperature) decreases w/ height along the geostrophic Momentum Surface (hereafter, Mg). This is known as the Mg-theta-e relationship which is needed for slantwise convection.
MPVg (Moist geostrophic potential Vorticity (or EPV / Equivalent potential Vorticity) is less than zero.
A quick note. Whenever there is the Mg-Theta relationship, negative MPVg will be present. I PREFER and RECOMMEND that you use MPVg over the Mg-theta relationship since you don’t have to worry about the orientation of the cross section.
CSI /Conditional Symmetric Instability:
Theta-es decreases w/ height along the Mg Surfaces. Mg-Theta-es relationship. MPVg* (* = saturated, thus MPVg* implies Saturated Moist potential geostrophic vorticity)
SOME researchers over the years have questioned the validity of blindly using theta-e in assessing CSI instead of suing theta-es. You can since the two will be equivalent to one another at saturation; however I prefer to use theta-es.
CSI and frontogenesis will almost always be found together. Frontogenesis simply indicates baroclinicity or tightening of the thermal gradient over a distance. Thusly since frontogenesis characterizes a region where the horizontal thermal gradient is stronger, the Mg surfaces are more likely to become increasingly horizontal and the pseudo adiabats more vertical. This can also be achieved in situations where strong vertical speed shear exists.
A deformation zone is an area of the atmosphere where winds diverge along one axis and converge along another.
BUFKIT is a software program which was developed by NWS Buffalo and the WDTB to analyze model data.
...
Jeb wrote:That is an excellent discussion of CSI banding, wxguy25. That is, by far, some of your best work!
I'll be back in a while with a few clarifying questions.
-Jeb
wxguy25 wrote:Jeb wrote:That is an excellent discussion of CSI banding, wxguy25. That is, by far, some of your best work!
I'll be back in a while with a few clarifying questions.
-Jeb
Actually it’s quite a rudimentary description. I could get alot more in depth and mathematical with it, but that wouldn’t be beneficial to anyone just wanting to learn the basics about it. besides, I would probably end up raising more questions than providing answers to the ones already being asked.
The nature of the banding will be two dimensional /quasi-symmetric, the criteria needed for the development of the banding is met in the region where the bands are found and the bands align themselves parallel to the thicknesses field (thermal wind). Remember this is b/c thermal wind flows parallel to the thickness gradient. Bands move at the same speed the flow is moving which means the bands themselves have a propagation of zero.
PSI / POTENTIAL Symmetric Instability:
Theta-e (Equivalent Potential Temperature) decreases w/ height along the geostrophic Momentum Surface (hereafter, Mg). This is known as the Mg-theta-e relationship which is needed for slantwise convection.
MPVg (Moist geostrophic potential Vorticity (or EPV / Equivalent potential Vorticity) is less than zero.
A quick note. Whenever there is the Mg-Theta relationship, negative MPVg will be present. I PREFER and RECOMMEND that you use MPVg over the Mg-theta relationship since you don’t have to worry about the orientation of the cross section.
CSI /Conditional Symmetric Instability:
Theta-es decreases w/ height along the Mg Surfaces. Mg-Theta-es relationship. MPVg* (* = saturated, thus MPVg* implies Saturated Moist potential geostrophic vorticity)
SOME researchers over the years have questioned the validity of blindly using theta-e in assessing CSI instead of suing theta-es. You can since the two will be equivalent to one another at saturation; however I prefer to use theta-es.
CSI and frontogenesis will almost always be found together. Frontogenesis simply indicates baroclinicity or tightening of the thermal gradient over a distance. Thusly since frontogenesis characterizes a region where the horizontal thermal gradient is stronger, the Mg surfaces are more likely to become increasingly horizontal and the pseudo adiabats more vertical. This can also be achieved in situations where strong vertical speed shear exists.
Chris the Weather Man wrote:Jeb.......... Go Here....... http://www.theweatherprediction.com That Site has EVERYTHING!
Chris the Weather Man wrote:Jeb.......... Go Here....... http://www.theweatherprediction.com That Site has EVERYTHING!
Chris the Weather Man wrote:Jeb.......... Go Here....... http://www.theweatherprediction.com That Site has EVERYTHING!
Jeb wrote:Conditional Symmetric Instability
I need to know everything about CSI!!!!
I would like you (wxguy25, or anyone else who cares to) to go into MUCH, MUCH more detail about several things you mentioned earlier........
Please go into MUCH GREATER DETAIL!
1) What is a Mesoscale process?
2) What is the difference between a mesoscale process and a synoptic process?
3) What does synoptic mean?
4) What is moist symmetric instability?
5) What are other forms of moist symmetrical instability besides CSI?
6) What is two dimensional, quasi-symmetric banding?
7) Please, if you would, please try to explain the following paragraph in more detail. I apologize for not having more of an understanding of these processes.
8) What are ducted gravity waves?
9) What is Kelvin-Helmholtz instability?
10) What are the different types of instability?
11) In the following quoted region below, I would like it if you would explain each bolded word or phrase in much more detail.
Please understand that you certainly DO NOT have to do this.
I am not trying to prove anything, I have less than a kindergarten understanding of weather. My whole life is eminently laughable; all I really understand is how to get way too excited over snow events and beach jebwalking.
I am only trying to understand something that is, to my level of understanding, approximately 500 centuries in my future LOL.
It's easy for me to understand that I get super excited about snow, then go jebwalking and experience endorphins then compound that phenomenon by blasting inspirational Christian music in state of the art stereo headphones smack-dab in the middle of a snow-filled jebwalk.
Even though I am admittedly years behind in my meteorological understanding, I still LOVE these discussions to no end!!!!
-Jeb
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