Why is Frances moving W to WSW now?

[Guest]

The last few satellite loops look like its move west for sure now, so how long will this last?

[lilbump3000]

This might last for atleast 36-48 hours as it will be under the influence of the building ridge. Also look for an increase in forward speed as well.

[cycloneye]

Wobbles.Hurricanes move on stairsteps.If you see after 6 frames that movement then is a trend.

[Frank P]

For the past 90 minutes she has been practically due west.... NO southern component at all... in fact the very lastest pix showed an almost insignificant wobble north, over all I say at best she's going just north of due west at the moment...

[TheShrimper]

It is not "due" west, as lattitude is being gained in the movement. Overall, the movement seems to be between 290-300 heading.

[x-y-no]

Looks to me like today's average is just a little north of west. Maybe 280 or so, not more than 285.

[x-y-no]

It is not "due" west, as lattitude is being gained in the movement. Overall, the movement seems to be between 290-300 heading.

LOL ... who knows, maybe you're rihgt and I'm wrong. I've always been a little shaky at eyeballing angles. My upper estimate and your lower one aren't too far apart, though.

[tampastorm]

Northerly, I say definantly if anything more southerly then northerly.

[hial2]

The 1800 NHC mdel suite initilized Francis 1 degree west from the 1200 model suite, SAME latitude..

Seems to me that at least between those times,heading DUE west

[golter]

It has been stairstepping for 3 days now. It has just begun another NW jog.

[CalmBeforeStorm]

It is not "due" west, as lattitude is being gained in the movement. Overall, the movement seems to be between 290-300 heading.

Based on the latest vortex message the storm has moved due west since 11:00.

B. 18 DEG 47 MIN N
55 DEG 14 MIN W

[Derecho]

It is not "due" west, as lattitude is being gained in the movement. Overall, the movement seems to be between 290-300 heading.

Based on the latest vortex message the storm has moved due west since 11:00.

B. 18 DEG 47 MIN N
55 DEG 14 MIN W

Wrong.

It's the old "minutes of arc" error. VORTEX statements use minutes of arc..60 minutes to a degree.

NHC statements convert that into Tenths of a degree.

The VORTEX places Frances at 18.8 N, 55.2 W.

Frances has gained .2 degrees of latitude since 11AM. Hence, it's NOT moving due West.

[Guest]

Does it still look like a wobble, or more of a trend?

[Ola]

It is not "due" west, as lattitude is being gained in the movement. Overall, the movement seems to be between 290-300 heading.

Based on the latest vortex message the storm has moved due west since 11:00.

B. 18 DEG 47 MIN N
55 DEG 14 MIN W

Wrong.

It's the old "minutes of arc" error. VORTEX statements use minutes of arc..60 minutes to a degree.




NHC statements convert that into Tenths of a degree.

The VORTEX places Frances at 18.8 N, 55.2 W.

Frances has gained .2 degrees of latitude since 11AM. Hence, it's NOT moving due West.

Correct me if I am wrong, but do they use minutes because of the curvature of the earth? Minutes is used for angles.

[MGC]

It is difficult to ascertain a heading using satellite looping. It will give you are rough direction but not a heading to a certain degree. That is why the hurricane hunter are there. Frances has been heading in a general west direction all afternoon......MGC

[Guest]

You know Derecho, I respect your meterological abilities as well as many others on this board but, lets call it like it is, a chicken is a chicken, same as a duck is a duck, now any reasonably intelligent individual can see a complete westward motion, dominating any gain in latitude. Watch the loop for yourself. Its this type of denial that caught S. Florida with their pants down with Charley.

http://www.ssd.noaa.gov/PS/TROP/DATA/RT ... -loop.html

If you average this loop out, you get due westward motion overall.

Brian

[Ola]

You know Derecho, I respect your meterological abilities as well as many others on this board but, lets call it like it is, a chicken is a chicken, same as a duck is a duck, now any reasonably intelligent individual can see a complete westward motion, dominating any gain in latitude. Watch the loop for yourself. Its this type of denial that caught S. Florida with their pants down with Charley.

http://www.ssd.noaa.gov/PS/TROP/DATA/RT ... -loop.html

If you average this loop out, you get due westward motion overall.

Brian

Movement bearings are calculated with something like 6 hour averages. A loop is not a 6 hour loop. If you could pick any time interval to calculate bearing you could have a diferent movement for a system every 30 minutes. In order for forecast and analisys to make sense and be valid you need consistency, and I mean use the same measuring parameters all the time so data can be compared.

[Guest]

You know Derecho, I respect your meterological abilities as well as many others on this board but, lets call it like it is, a chicken is a chicken, same as a duck is a duck, now any reasonably intelligent individual can see a complete westward motion, dominating any gain in latitude. Watch the loop for yourself. Its this type of denial that caught S. Florida with their pants down with Charley.

http://www.ssd.noaa.gov/PS/TROP/DATA/RT ... -loop.html

If you average this loop out, you get due westward motion overall.

Brian

Movement bearings are calculated with something like 6 hour averages. A loop is not a 6 hour loop. If you could pick any time interval to calculate bearing you could have a diferent movement for a system every 30 minutes. In order for forecast and analisys to make sense and be valid you need consistency, and I mean use the same measuring parameters all the time so data can be compared.

This loop is over 5 hrs in length, what are you talking about?

Brian

[Ola]

On the other hand , Frances could move due west for the next 6 hours. NHC called a 290 movement and that means what it HAD been doing.

[Guest]

Well when we don't have current recon data alot of people on this board use satellite loops to base their conclusions, so why can't we say Frances has had a WSW dwooble