Is it possible to look up old soundings from certain weather offices?

[Andrew Clope]

I was looking at heading up to IA yesterday afternoon 7-6-2014 and decided to opt out because the 0-1km SRH and 0-3km SRH just didn't look good. Bulk shear looked bad, CAPE was great. Lifting was there as the cold front pushed SE. I figured at best it would just be a few cells pop up, anvil out, rain/hail/ be messy and turn into an MCS... Then the BEAUTIFUL LP supercell near Traer, IA touched down... what the heck happened?? I couldn't have been more wrong.

So I was wanting to check out a sounding from last night at 6pm to see if things changed, the models were that far off, or if I am still just that inept at forecasting this stuff.

Thanks!

 

[mikedeason]

If you need soundings from the last seven days, try this one:

http://www.spc.noaa.gov/exper/soundings/

For archives going further back, this is my favorite site:

http://vortex.plymouth.edu/raob_conus-u.html

Regards

 

[Andrew Clope]

Mike,

Thank you very much for those links. With the SPC one I choose 7-6-14 2200 UTC, which obviously is 5 PM CST, but can only choose from 3 locations across the US (OAX/TOP/1Y7), what's the reason for that? Am I missing something?

Thanks

 

[Mark Blue]

Here's another alternative using forecasted soundings from the 21Z RUC yesterday. You can select +3 HRS in the left panel to arrive at 0Z for Waterloo, IA, or other times if you wish. See if this link works for you.

Mike gave you observed soundings whereas these are forecast soundings. The main page for searching forecast soundings using various models on Earl's website is here.

 

[mikedeason]

Yeah, the RUC soundings are going to be the best proxy for finding a representative sounding during the time you're looking at.

 

[Andrew Clope]

Here's another alternative using forecasted soundings from the 21Z RUC yesterday. You can select +3 HRS in the left panel to arrive at 0Z for Waterloo, IA, or other times if you wish. See if this link works for you.

Mike gave you observed soundings whereas these are forecast soundings. The main page for searching forecast soundings using various models on Earl's website is here.

Guys, thank you so much for the info. 2 possibly dumb questions though... 1) I'm working through a few of Tim Vasquez' books and keep seeing RUC, I will google this to see what it is, but wanted to hear what it is from you guys as well as it seems that hearing it in simple terms sometimes helps when comparing it to "official" definitions. And 2) how accurate are official soundings as compared to forecast soundings?

Thanks

 

[Andrew Clope]

Also** another question... I thought that every weather office across the US did soundings twice a day, so shouldn't they all have a sounding for 12 UTC and 00 UTC?

 

[Andrew Clope]

So using Marks link I came up with this, but have a few questions. Using the SRH profile, it seems VERY apparent why those tornadoes spun up yesterday, but I want to make sure that I'm reading this sounding correctly (I will try to attach picture that I quickly edited to make sure I understand correctly).

**And it's blurry when blown up, basically, I just wanted to know if on the left it's SRH and on the right it's environmental? And if the hodograph represents environmental.

 

[Mark Blue]

The RUC stands for Rapid Update Cycle and is a model that is used for short term mesoscale forecasting. Mike knows more about this than me, but the RUC updates quickly, thus its name. You are correct about 0Z and 12Z observed soundings, those are the standard times. The off hour soundings are for special situations such as a high probability for severe, so the WFO will send up another balloon and radiosonde to take additional readings. It helps them get a better handle on the environment for that day.

 

[Jeff Duda]

The RUC is no longer run as an official forecast model. That's one of the disadvantages to writing a book about operational meteorology - it becomes outdated as technology changes.

The model you currently want to look at is the RAP (rapid refresh), which is the updated version of the RUC.

It is not the case that every NWS forecast office launches soundings every day. In fact, only about half of them do. I personally think that's stupid, but the spatial density is still sufficient to resolve the synoptic scale state of the atmosphere, which is generally the goal of the rawinsonde program.

 

[Mark Blue]

The RUC is no longer run as an official forecast model. That's one of the disadvantages to writing a book about operational meteorology - it becomes outdated as technology changes.

The model you currently want to look at is the RAP (rapid refresh), which is the updated version of the RUC.

It is not the case that every NWS forecast office launches soundings every day. In fact, only about half of them do. I personally think that's stupid, but the spatial density is still sufficient to resolve the synoptic scale state of the atmosphere, which is generally the goal of the rawinsonde program.

Jeff is one of the experts in this arena, so thanks to him for clarifying the finer details of the rawinsonde program (not radiosonde - my bad). I personally don't see how increasing the spatial density could hurt, but that's a topic for another day. I didn't see the RAP on Earl's website as an option for archived soundings, only the NAM, GFS, and RUC. Perhaps he's using one of the RAP flavors to feed data into what he calls the RUC.

 

[rdale]

Also** another question... I thought that every weather office across the US did soundings

No. Only upper air sounding locations.

twice a day, so shouldn't they all have a sounding for 12 UTC and 00 UTC?

Yes, but you said you looked at 22Z and that means special soundings were requested.

 

[Rob H]

Jeff is one of the experts in this arena, so thanks to him for clarifying the finer details of the rawinsonde program (not radiosonde - my bad).

Most radiosondes are rawinsondes except when their position isn't explicitly tracked. At the risk of offending any pedants here on ST, they're essentially interchangeable (for the average amateur)

I love Earl's charts, but with so little context provided to what you're actually looking at, I'm a little fearful of his data.