Using Hovmoller Series to Track Tropical Waves

[MWatkins]

I've seen this discussion come up a few times lately...so I figured I would chip in here.

One common mistake when evaluating the tropics is looking at imagery over too short a time. Yes...this comes up all the time with wobbles...but also when trying to trend cyclogenesis. And ALWAYS when watching radar.

To help the human eye look at longer term changes in structure, Hovmoller diagrams are used to compare point-in-time satellite imagery to get a better overview of what has changed. That way a forecaster can not only see the imagery...but follow the progression of the features easily over time. These are also used to track Kelvin Waves, the MJO etc. But for now...let's stick to satellite imagery.

Brian McNoldy at Colorado State has a page maintaining these diagrams...here is one for the deep tropics:

http://einstein.atmos.colostate.edu/~mc ... /atlantic/

Here is the main page:

http://einstein.atmos.colostate.edu/~mc ... hovmoller/

Pretty cool, eh?

Hard to discern any changes in the last 12 hours with 97L...for example. Using IR 2 the envelope seems more circular than it was yesterday...but it's hard to see that in this imagery.

MW

[SouthFloridawx]

I really like that image you posted. Thanks for remiding me about it.

[SouthAlabamaWX]

I've seen this discussion come up a few times lately...so I figured I would chip in here.

One common mistake when evaluating the tropics is looking at imagery over too short a time. Yes...this comes up all the time with wobbles...but also when trying to trend cyclogenesis. And ALWAYS when watching radar.

To help the human eye look at longer term changes in structure, Hovmoller diagrams are used to compare point-in-time satellite imagery to get a better overview of what has changed. That way a forecaster can not only see the imagery...but follow the progression of the features easily over time. These are also used to track Kelvin Waves, the MJO etc. But for now...let's stick to satellite imagery.

Brian McNoldy at Colorado State has a page maintaining these diagrams...here is one for the deep tropics:

http://einstein.atmos.colostate.edu/~mc ... /atlantic/

Here is the main page:

http://einstein.atmos.colostate.edu/~mc ... hovmoller/

Pretty cool, eh?

Hard to discern any changes in the last 12 hours with 97L...for example. Using IR 2 the envelope seems more circular than it was yesterday...but it's hard to see that in this imagery.

MW

Yeah, pretty cool. I know a forecaster who hand plots a hovmoller several times a week. Very interesting.

Also, off topic. I seen an article about you in today's (Tuesday) newspaper. Good article.

[fci]

Can you post a link to the article?

[beachbum_al]

Those are interesting. Thanks for posting the link.

[O Town]

Thanks for the link I have added it to my favs. Very good way to look at progress or not of a system. Cool.