Weather chart oddity?

[Dylan Smith]

OK, I've never seen this before.

Take a look at the synoptic chart I've saved at
http://www.alioth.net/tmp/fronts.gif

There is a cold front, just south west of Ireland. The 'sharks teeth'
are outlines, rather than filled in. The other week I saw a warm front
drawn like this. What's the difference between this and a 'normal' cold
front?

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[Peter R.]

Dylan Smith > wrote:

<snip>
> The other week I saw a warm front
> drawn like this. What's the difference between this and a 'normal' cold
> front?

I use ADDs for prognostic charts and these charts often contain the warm
front that has not been colored in, which represents a "dry line."

http://www.hpc.ncep.noaa.gov/html/fntcodes2.shtml

A dry line is defined as "a boundary between warm, dry air and warm, humid
air in the southeast sector of a mature midlatitude cyclone; likely site
for severe thunderstorm development."




--
Peter

[Casey Wilson]

"Dylan Smith" > wrote in message
...
> OK, I've never seen this before.
>
> Take a look at the synoptic chart I've saved at
> http://www.alioth.net/tmp/fronts.gif
>
> There is a cold front, just south west of Ireland. The 'sharks teeth'
> are outlines, rather than filled in. The other week I saw a warm front
> drawn like this. What's the difference between this and a 'normal' cold
> front?
>

Hmmm, do a google for "occluded front" and see if that answers your
question.

[Matt Barrow]

"Casey Wilson" <N2310D @ gmail.com> wrote in message
news:ilO1g.9711$oQ2.398@trnddc05...
>
> "Dylan Smith" > wrote in message
> ...
>> OK, I've never seen this before.
>>
>> Take a look at the synoptic chart I've saved at
>> http://www.alioth.net/tmp/fronts.gif
>>
>> There is a cold front, just south west of Ireland. The 'sharks teeth'
>> are outlines, rather than filled in. The other week I saw a warm front
>> drawn like this. What's the difference between this and a 'normal' cold
>> front?
>>
>
> Hmmm, do a google for "occluded front" and see if that answers your
> question.
Why doesn't everyone unsubscribe from this group and just bang around GOOGLE
all day?

[Dylan Smith]

On 2006-04-20, Casey Wilson > wrote:
> Hmmm, do a google for "occluded front" and see if that answers your
> question.

Except it's not an occluded front. An occluded front has a line with
both the 'sharks teeth' and the warm front semicircles on it, the sharks
teeth and semicircles filled in (and if in colour, drawn in magenta) and
on the leading edge of the occluded front. What is depicted is
definitely not the symbology for an occluded front. (There is an
occluded front behind it - straggling the centre of the 998 millibar low
pressure system that is following the cold front with the white sharks
teeth).

Besides, the weather systems are moving eastbound, and for an occlusion
to occur, a cold front must catch up with a warm front. Cold fronts
generally travel faster than warm fronts. This particular front is ahead
of another cold front and appears to cross a stationary front at one
point.

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[Dylan Smith]

On 2006-04-20, Peter R. > wrote:
> Dylan Smith > wrote:
>
><snip>
>> The other week I saw a warm front
>> drawn like this. What's the difference between this and a 'normal' cold
>> front?
>
> I use ADDs for prognostic charts and these charts often contain the warm
> front that has not been colored in, which represents a "dry line."

Well, the exception here is that both the cold front with unfilled
sharks teeth and the warm front with unfilled semicircles both occured
over the Atlantic Ocean - not the sort of place you expect to find a dry
line!

--
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[Montblack]

("Matt Barrow" wrote)
> Why doesn't everyone unsubscribe from this group and just bang around
> GOOGLE all day?


No need to unsubsribe from this group. A person CAN manage to do both. :-)


Montblack
http://www.tallpaul.com/downloads/movs/BOTD.mov
<chuckle>

[Icebound]

"Dylan Smith" > wrote in message
...
> OK, I've never seen this before.
>
> Take a look at the synoptic chart I've saved at
> http://www.alioth.net/tmp/fronts.gif
>
> There is a cold front, just south west of Ireland. The 'sharks teeth'
> are outlines, rather than filled in. The other week I saw a warm front
> drawn like this. What's the difference between this and a 'normal' cold
> front?
>

http://www.msc-smc.ec.gc.ca/education/msi/m4/4g167_e.cfm#193

Notwithstanding the rather bizarre structure which your chart-analyst
appears to see.....

..... what an unfilled cusp is *supposed* to indicate is an "upper" front".

An upper front is a *steepening* of the slope in the cold air, such that a
station at the surface does not notice any change in air mass per se, but it
notes the *effects* of a cold front passage (or a warm front passage)
because the structure *above* him corresponds to the classic cold-front or
warm-front scenario.

Note the cross-sections slightly higher up the same page, at "frame 188"

[Matt Barrow]

"Montblack" > wrote in message
...
> ("Matt Barrow" wrote)
>> Why doesn't everyone unsubscribe from this group and just bang around
>> GOOGLE all day?
>
>
> No need to unsubsribe from this group. A person CAN manage to do both.
> :-)

Ambidextrous?


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO