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.

 

Forums

Back

NBM v4.1 blacklisting observation update

RSS (Opens New Window)(Opens New Window)
Jeffrey Craven, modified 2 Years ago.

NBM v4.1 blacklisting observation update

Youngling Posts: 90 Join Date: 9/24/12 Recent Posts
Since the NBM went to matching METARS, there have been some undesirable side effects like frozen AWOS 6 hour Max/Min groups and bad Tds causing unrealistic forecasts from NBM.  

Here is an example from KMZZ in Indiana, where the AWOS MaxT MinT 6 hour group has been stuck at 87F High and -12F Low for a while.  This site has been blacklisted by the local WFO using the process via RTMA/URMA.  



The NBM v4.0 forecast 104F today at that location as a result of the bias correction from the erroneous observation, with a low tonight of about 10F.   Until the owner of the AWOS has this issue repaired, NBM v4.0 will continue to bias-correct to the bogus 99F diurnal range.  

Recently, Scott Scallion has worked on a method (in collaboration with EMCs RTMA/URMA group) to check the URMA blacklisted observations and remove them from use in NBM METAR matching.   If an observation is blacklisted in URMA, in v4.1 it will instead use the URMA grid point (as it does for all none METAR grid points).   If the site is removed from the URMA blacklist, the METAR (or some of the RAW sites) will be used again instead of the URMA value at the grid point.  

This change has recently been added to the real time NBM v4.1 parallel runs, and you can see that KMZZ forecasts are starting to drift toward more realistic levels.   Highs are already 3-8F cooler and lows 15-23F warmer in just a couple of weeks of having this running in the real time tag.  Obviously in these cases it will take at least a couple of months for the NBM forecast values to become realistic again, but this does allow us to directly use the URMA blacklist to make sure NBM v4.1 stops using METARs and RAWs sites that are selected by local WFOs as having unrepresentative or erroneous values.  





JPC

Jeff Craven
Chief, Statistical Modeling Division (SMD)
Vice Lead, Innovation, Science & Technology (Evolve PMO)
National Weather Service, W/STI-12
Meteorological Development Laboratory (MDL)
Room 10410, SSMC2
Silver Spring, MD 20910
(816) 506-9783 cell/text
(301) 427-9475 office
@jpcstorm

Attachments:

Attachment

Attachment

Attachment

MH
Matthew Hirsch, modified 2 Years ago.

RE: NBM v4.1 blacklisting observation update

Youngling Posts: 2 Join Date: 2/27/15 Recent Posts
I was unaware the URMA is matching temperatures at the METAR points. I thought the matching was just limited to wind/wind gust. Is there any documentation about this change? Is this in effect with the current version of the URMA?

Thanks,
Matt - Phoenix

On Fri, May 13, 2022 at 2:16 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:
Since the NBM went to matching METARS, there have been some undesirable side effects like frozen AWOS 6 hour Max/Min groups and bad Tds causing unrealistic forecasts from NBM.  

Here is an example from KMZZ in Indiana, where the AWOS MaxT MinT 6 hour group has been stuck at 87F High and -12F Low for a while.  This site has been blacklisted by the local WFO using the process via RTMA/URMA.  



The NBM v4.0 forecast 104F today at that location as a result of the bias correction from the erroneous observation, with a low tonight of about 10F.   Until the owner of the AWOS has this issue repaired, NBM v4.0 will continue to bias-correct to the bogus 99F diurnal range.  

Recently, Scott Scallion has worked on a method (in collaboration with EMCs RTMA/URMA group) to check the URMA blacklisted observations and remove them from use in NBM METAR matching.   If an observation is blacklisted in URMA, in v4.1 it will instead use the URMA grid point (as it does for all none METAR grid points).   If the site is removed from the URMA blacklist, the METAR (or some of the RAW sites) will be used again instead of the URMA value at the grid point.  

This change has recently been added to the real time NBM v4.1 parallel runs, and you can see that KMZZ forecasts are starting to drift toward more realistic levels.   Highs are already 3-8F cooler and lows 15-23F warmer in just a couple of weeks of having this running in the real time tag.  Obviously in these cases it will take at least a couple of months for the NBM forecast values to become realistic again, but this does allow us to directly use the URMA blacklist to make sure NBM v4.1 stops using METARs and RAWs sites that are selected by local WFOs as having unrepresentative or erroneous values.  





JPC

Jeff Craven
Chief, Statistical Modeling Division (SMD)
Vice Lead, Innovation, Science & Technology (Evolve PMO)
National Weather Service, W/STI-12
Meteorological Development Laboratory (MDL)
Room 10410, SSMC2
Silver Spring, MD 20910
(816) 506-9783 cell/text
(301) 427-9475 office
@jpcstorm

--
Jeffrey Craven RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/22148785VLab.Notifications@noaa.gov
Jeffrey Craven, modified 2 Years ago.

RE: NBM v4.1 blacklisting observation update

Youngling Posts: 90 Join Date: 9/24/12 Recent Posts
NBM v4.0 is matching METARs, not URMA.    We take URMA grid, and insert the METAR observation into that grid point only at about 2,500 AWOS/ASOS sites.  

MaxT, MinT, Temp, Td, wind speed, wind gust are the elements.



JPC

Jeff Craven
Chief, Statistical Modeling Division (SMD)
Vice Lead, Innovation, Science & Technology (Evolve PMO)
National Weather Service, W/STI-12
Meteorological Development Laboratory (MDL)
Room 10410, SSMC2
Silver Spring, MD 20910
(816) 506-9783 cell/text
(301) 427-9475 office
@jpcstorm


On Tue, May 17, 2022 at 4:46 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:
I was unaware the URMA is matching temperatures at the METAR points. I thought the matching was just limited to wind/wind gust. Is there any documentation about this change? Is this in effect with the current version of the URMA?

Thanks,
Matt - Phoenix

On Fri, May 13, 2022 at 2:16 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:
Since the NBM went to matching METARS, there have been some undesirable side effects like frozen AWOS 6 hour Max/Min groups and bad Tds causing unrealistic forecasts from NBM.  

Here is an example from KMZZ in Indiana, where the AWOS MaxT MinT 6 hour group has been stuck at 87F High and -12F Low for a while.  This site has been blacklisted by the local WFO using the process via RTMA/URMA.  



The NBM v4.0 forecast 104F today at that location as a result of the bias correction from the erroneous observation, with a low tonight of about 10F.   Until the owner of the AWOS has this issue repaired, NBM v4.0 will continue to bias-correct to the bogus 99F diurnal range.  

Recently, Scott Scallion has worked on a method (in collaboration with EMCs RTMA/URMA group) to check the URMA blacklisted observations and remove them from use in NBM METAR matching.   If an observation is blacklisted in URMA, in v4.1 it will instead use the URMA grid point (as it does for all none METAR grid points).   If the site is removed from the URMA blacklist, the METAR (or some of the RAW sites) will be used again instead of the URMA value at the grid point.  

This change has recently been added to the real time NBM v4.1 parallel runs, and you can see that KMZZ forecasts are starting to drift toward more realistic levels.   Highs are already 3-8F cooler and lows 15-23F warmer in just a couple of weeks of having this running in the real time tag.  Obviously in these cases it will take at least a couple of months for the NBM forecast values to become realistic again, but this does allow us to directly use the URMA blacklist to make sure NBM v4.1 stops using METARs and RAWs sites that are selected by local WFOs as having unrepresentative or erroneous values.  





JPC

Jeff Craven
Chief, Statistical Modeling Division (SMD)
Vice Lead, Innovation, Science & Technology (Evolve PMO)
National Weather Service, W/STI-12
Meteorological Development Laboratory (MDL)
Room 10410, SSMC2
Silver Spring, MD 20910
(816) 506-9783 cell/text
(301) 427-9475 office
@jpcstorm

--
Jeffrey Craven RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/22148785VLab.Notifications@noaa.gov

--
Matthew Hirsch RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/22204528VLab.Notifications@noaa.gov

Bookmarks

Info Icon Descriptive
  • Items Selected
Info Recycle Bin

Home

Folder
# of Items

3

There are no bookmarks in this folder.