Welcome

Welcome to the RTMA/URMA VLab community!

The purpose of this community is to facilitate feedback and discussion on the RTMA/URMA system. 

Meeting notes are available under the Google Drive Folder linked above.

To learn more about our next upgrade, see the asset publication below.

Use the System Overview to learn more about the system in general.

Use the forum to ask questions about the system and join the discussion with other users and the development team. 

Note that there are two forums: one for precipitation issues and one for all other variables.

You can post to the precip issues forum by sending an email to qpe.rtma.urma.feedback.vlab@noaa.gov.  For all other issues, you can post by sending an email to rtma.feedback.vlab@noaa.gov.  Please note that you must have a user account to post to the forum.  If you do not have an account, please contact matthew.t.morris@noaa.gov.

We recently added the ability for NWS Regional or WFO personnel to request that stations be removed from the analysis.  To access this, click on the "Station Reject Lists and Requests" tab.

There has been recent interest in knowing exact station locations, especially those of METAR sites.  Our METAR information table is under the "METAR Location Info" tab.

Users may also be interested in the National Blend of Models VLab community.

We appreciate any feedback on how this page or community could be improved.  You can submit such feedback via the above email handle or forum.

 

What's New

December 2017 Implementation Summary

Document

Overview of upgrade scheduled for December 2017. Note that this was originally scheduled for October 2017, but has been pushed back due to technical issues.

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More Details
Modified Date
10/31/17

Forums

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URMA Wind Direction Question

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Joe Lester, modified 1 Year ago.

URMA Wind Direction Question

Youngling Posts: 12 Join Date: 6/12/17 Recent Posts

I was just hoping you could clarify something. It seems that URMA does not ingest observed wind direction, like it does speed and gust...is this correct? Thus, those wind direction adjustments/bias corrections do not get into the nbm, right?

MM
Matthew Morris, modified 1 Year ago.

RE: URMA Wind Direction Question

Youngling Posts: 156 Join Date: 12/6/17 Recent Posts
Hi Joe,

RTMA and URMA analyze the wind in two different ways simultaneously and combine the results together in the end.  The first method uses streamfunction and velocity potential as control variables to analyze wind as a vector quantity.  The final streamfunction and velocity potential are converted to wind speed and wind direction.  The second method is the direct analysis of wind speed only.  Because wind speed is a scalar quantity, the resulting analysis is generally more accurate than the wind speed obtained from the first method.  The final RTMA and URMA wind (vector) analysis comprises the wind speed from the second method and the wind direction from the first method.  Note that the direct analysis of wind direction is not a trivial matter due to the cyclical nature of this quantity.  Also note that wind gust is only analyzed as a scalar quantity.

For questions regarding how this information is used in the NBM, I'd suggest reaching out to the NBM team.

Thanks,
Matt

On Fri, Oct 14, 2022 at 7:18 AM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

I was just hoping you could clarify something. It seems that URMA does not ingest observed wind direction, like it does speed and gust...is this correct? Thus, those wind direction adjustments/bias corrections do not get into the nbm, right?


--
Joe Lester RTMA/URMA Discussion Group Virtual Lab Forum https://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/25421083VLab.Notifications@noaa.gov


--
Matthew Morris
SAIC at NOAA/NWS/NCEP/EMC
5830 University Research Ct., Rm. 2038
College Park, MD 20740
301-683-3758

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  • 2011 RTMA Paper (Weather and Forecasting)

    The most recent peer-reviewed paper on the RTMA. Published in Weather and Forecasting in 2011.
    7 Visits

  • Public RTMA/URMA Viewer

    Another viewer of the current RTMA/URMA, with an archive going back 24 hours. This version is open to the public, but does not contain information about the (many) restricted obs used.
    52 Visits

  • RAP downscaling conference preprint (23rd IIPS)

    This link is to a presentation from the (then) RUC group on how the downscaling process works. Although we now use the RAP, HRRR, and NAM, the logic of the downscaling code is mostly unchanged from this point.
    2 Visits