Where do you get your plotted maps for hand analysis?

[Patrick Marsh]

...In some ways it's old school, but unfortunately the new computer generated surface graphics (we find online) do not have the resolution to equal this...Pretty colors and online graphics likely won't take you to that level of detail.

I hope you aren't including gempak in this "computer generated surface graphics". I guarantee you that I can create a detailed an image in gempak that is as detailed as a DA. (Un-analyzed) No offense to Tim or his hard work with DA, but for generating surface plots for contouring, gempak can be just as good.

The benefit to DA is that it can run on a PC, whereas gempak uses a *nix kernel.

Here are some gempak example images:

http://weather.ou.edu/~pmarsh/METR2021/HAND ANALYSIS/

I can make these bigger, smaller, more detailed, less detailed, etc

 

[Andrea Griffa]

I hope you aren't including gempak in this "computer generated surface graphics". I guarantee you that I can create a detailed an image in gempak that is as detailed as a DA. (Un-analyzed) No offense to Tim or his hard work with DA, but for generating surface plots for contouring, gempak can be just as good.

The benefit to DA is that it can run on a PC, whereas gempak uses a *nix kernel.

Here are some gempak example images:

http://weather.ou.edu/~pmarsh/METR2021/HAND ANALYSIS/

I can make these bigger, smaller, more detailed, less detailed, etc

I can't see the page that you linked(forbidden)

 

[Patrick Marsh]

Thanks for letting me know about the link. Last night after the lab I teach, I changed my directory's file permissions and disabled all permissions for all users but me. I totally forgot I had this link up. I've fixed that issue now.

Again, sorry for that...

 

[rdale]

Tweaked my GEMPAK page and linked more example, also I'll have a version that will run within Windows by Feb.

http://skywatch.org

 

[Bill Schintler]

RE: Maps for hand analysis

****Upper-air****:

SPC:
Scroll down to "Unanalyzed maps (.pdf format)
http://www.spc.noaa.gov/obswx/maps/

I still print those out on 8-1/2 by 11, but it is getting to the point where the data is becoming increasingly difficult to read with the small lettering. New charts are usually available by 1:30Z and 13:30Z. I print the 850, 700, and 500 charts twice a day and analyze them; starting with isopleths at 30m, 30m, and 60m intervals; respectively.

850 chart: Note moisture and temperature features; and other key features such as troughs.

700 chart: Plot isotherms at 5C intervals and features such as short wave axis and speed maximums.

500 chart: Note trough and ridge axis, shortwave axis, and isotachs.

I then compare each chart with the -12 hr chart (and sometimes -24 hr), and note where height falls/rises are concentrated. Temperature and moisture advection trends are also important for 850 and 700mb charts.

With practice, I've gotten to the point where I can do each UA chart in about five minutes. I make this a part of my daily routine, regardless of whether or not any active WX is underway, often while on break.

****Surface****:

Various sources, including COD (increasingly unreliable in recent years), UCAR, SPC (mesoanalysis), and Digital Atmosphere.

COD (select "Image Plot" for the state of interest):
http://weather.cod.edu/analysis/analysis.states.html

UCAR regional plots:
http://www.rap.ucar.edu/weather/surface/

SPC mesoanalysis"
http://www.spc.noaa.gov/exper/mesoanalysis/

Digital Atmosphere:
http://www.weathergraphics.com/da/

- bill

 

[John Hudson]

Just wanted to jump in on this one and make an inquiry. Gempak runs on -nix kernel systems, and I've got my laptop set up to dual-boot XP or Ubuntu. This means I can use the Gempak on my machine?

Not to worry, Tim. I'll be getting DA, too. Not just as an alternative, but I believe in supporting our own, whenever possible. Great job on the Map Handbook, by the way. Just got my copy before Christmas, and enjoying it throroughly.

John

 

[rdale]

Yes you can dual-boot and run GEMPAK.

What I've got coming next month is a version that will run within VMWare's free player, so you can have both Windows & Linux running at the same time.

 

[John Hudson]

Sounds like a great app, thanks a lot!

I'll be looking forward to it.


John

 

[Gene Moore]

I hope you aren't including gempak in this "computer generated surface graphics". I guarantee you that I can create a detailed an image in gempak that is as detailed as a DA. (Un-analyzed) No offense to Tim or his hard work with DA, but for generating surface plots for contouring, gempak can be just as good.

My comment was aimed at a number of online surface maps, COD, NCAR etc. I think DA's got them beat. Of course that's personal preference. In my Digital Atmosphere I have the station plots and contouring set up the way I like it...I tend to like less smoothing and tight altimeter plots. Also, I'm not going to do a total hand analysis (pressure) while driving down the highway. Because of where I live much of my chasing is done alone. So I let the program run with my settings while I drive. As for Gempak, it's great but I want to run my analysis on my laptop. My concept of chasing is far from the norm today, the less equipment the less distractions the better.

 

[rdale]

If you are a 'hard core' user, you'll want a dedicated box and/or dual-boot. And you don't need high-end equipment, so literally $300 or less will get you the hardware.

The Windows VMWare version is more for laptop users, something basic to get you going while mobile (I use it when in high-speed Verizon areas) because running Windows + Linux + all the memory that GEMPAK data files use can really slow you down.

 

[George Tincher]

Wow. What a great discussion this has turned out to be. It looks like both GEMPAK and DA have a great deal to offer and that you can't really go wrong with either. I may end up doing what I ultimately do in situations in which I can't make a decision between two similar yet different products......GET BOTH! LOL.

 

[Gene Moore]

Wow. What a great discussion this has turned out to be. It looks like both GEMPAK and DA have a great deal to offer and that you can't really go wrong with either. I may end up doing what I ultimately do in situations in which I can't make a decision between two similar yet different products......GET BOTH! LOL.

I think if you go to the trouble to set up GEMPACK for the road you'll not want to bother with DA. I haven't checked Tim's software site recently, but he did have a download trial (30 days?) for Digital Atmosphere. This would be a good time to try it out. In fact if the models are correct you'll get a good storm event to see how you like it.

Also, there are likely quite a few surface stations that have been added since the program was written. If you do decide to use it you'll need to upgrade those sites before spring to get good station density. Tim used to have directions on his site about how to get into the script to do that.

 

[George Tincher]

Thanks, Gene. Good advice. Whatever I end up going with will be added to my home PC, rather than a notebook. And it is Windows based. I'll be doing most of my analysis here at home. So if I were to opt for GEMPAK, I'd need to wait on Rob's February update. It seems I am good to go as is for Digital Atmosphere.

As a temporary solution, until I figure out exactly what program I want to purchase, I have elected to start using the COD unanalyzed maps. But to avoid the heavy clutter of those maps, I traced out some master copies of their regional storm chasing versions. I just added each station (empty circles) and left everything else blank. I have access to a terrific copier, so I will print out a bunch of these blank maps on regular 8.5x11 paper. Being they are exact duplicates of the COD maps in terms of size and stations, I can use them to overlay on my flat panel screen and match up data to the proper stations. I will then fill in the data (i.e. wind shafts/barbs, temperature, dewpoint, pressure, cloud cover, etc on sfc maps) using fine point color pens. I can write down the obs much smaller than they are shown in the originals. That way the map will be nice, neat and highly readable, rather than cluttered like they are originally. The upper air maps will be easier to deal with as they are. So that's a plus. Yes, that will create a little extra work on my part. But that's ok. Until I get a better solution in place, it's the only way I have been able to create working maps that are large enough to be beneficial yet small enough to complete on standard size paper. It's not ideal, but it will work for now until I get something better.

Thanks again to all who have replied and assisted me in my search for a better mouse trap. Hopefully this thread has also been helpful for others interested in hand analysis and looking for the tools to help generate your own plotted maps.