Jump to content
GMS, SMS, and WMS User Forum
Zia

HEC-HMS snowmelt modelling

Recommended Posts

I am using HEC-HMS version 3.3 to model snowmelt, and have following question:

1. I have tried different sets of ATI (antecedant temperature index) meltrate function but every time I get the error message "Requested interpolation value is above the last value in table of ATI meltrate function". What are reasonable values for the ATI meltrate function? Please see attached the table I am using as ATI meltrate function.

2. When I run the model, I get an error message that melt rate is undefined for my first time step (even though I have numbers for ATI function and coefficient. How can I correct this error?

Many Thanks,

Zia

ATI meltrate function.txt

Share this post


Link to post
Share on other sites

Zia,

I'd just make sure all the stuff is defined that needs to be defined for the snowmelt function. I would also check the HMS help and search for help on the internet about the HMS snowmelt function if needed.

Chris

Share this post


Link to post
Share on other sites

Hi,

I have the same problem with ATI-meltrate function.My HEC-HMS model is running but it's giving the following error message for some days:

"ERROR 21550: Melt rate is undefined at time 4 April 1990, 01:00:00."

Can you suggest anything to resolve this error?

---Zakia

Share this post


Link to post
Share on other sites

Zakia,

We have had similar problems with the HEC-HMS snowmelt functions. This appears to be a problem with HMS rather than WMS, and I know the HMS developers were working on fixing the problem, but the fix may not be available until HMS version 3.5 is released. You may be able to work around the problem. Contact our tech support for more information.

Chris

Share this post


Link to post
Share on other sites

Hi

I get the same error (melt rate undefined at ---) even with version 3.5 when use reasonable numbers for ATI and melt rate function. The model runs only with very high ATI like 45 degree C-day!!!!!.

Zak

Share this post


Link to post
Share on other sites

Zak,

If you send me your zipped HMS model, I could look at it and see if I can find anything wrong right away. Without looking at your model, it's hard to tell what the problem is. If you're sure you have set everything up correctly, you could try to contacting somebody at HEC using the HMS bug report page here and let them know about the bug. You may get some help going that route.

Here's some general advice:

1. Make sure all the model input is setup correctly.

2. Read the information about HMS snowmelt on this forum topic.

3. If you are current with your WMS maintenance, you could contact Aquaveo tech support and see if they can help you.

The Aquaveo consulting team could also help you get your model running. They charge an hourly consulting rate, but are very knowledgeable and should be able to help you get the results you need.

From my experience in running HMS, everything needs to be setup correctly to get things running. Let me know if I can help in any way.

Chris

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×