RTMA / URMA dewpoint issue in Iowa impacting the NBM All - Home - RTMA/URMA Discussion Group

Matt,

  Thanks for doing this study!  I have looped in the DMX SOO who can give the approval to blacklist the problematic stations noted in the slideset.

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

On Mon, Jun 5, 2023 at 3:05 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

Please take a look at the attached slides, which are from the 20230604 12Z RTMA output.

 RTMA Dewpoint Case Study - Central Iowa

Based on my findings, the IADOT station that you identified does not appear to be responsible for the region of low dewpoints in north central Iowa.  For example, in the case examined, there is a large, negative increment in the specific humidity field, yet the observation and background values for RWII4 were 10.91 and 10.89 g/kg, respectively.

Instead, it appears that there are numerous low-biased SYNOPTIC/DAVIS stations in the area highlighted on slide 4.  Selected stations in the red box are shown in the tables on slides 5-7.  Several stations initially failed the gross-error check, but the "partial analysis" values were lowered sufficiently by the nearby stations to allow the observations to be used on subsequent outer loops; these stations are indicated in red text on slides 5-7.

Thus, my recommendation would be to add all of the stations listed in the tables, with the exception of RWII4, to the reject list for moisture.  We ran a quick test case that confirms this should help address the issue.  Then, we can keep an eye on the analysis to see if it improves and if any additional stations need to be rejected.  However, we would need to have this approved by the local forecast office (DMX) before we proceed.

Thanks,

Matt

On Wed, May 24, 2023 at 4:31 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

We will take a closer look at the dew point analyses in this area and follow-up with you soon.  In the meantime, please see my answers to your other questions below:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
   We don't have a site currently that lists the observations going into RTMA/URMA.  However, we do have KML observation files available here.  These can be viewed in Google Earth.  However, please note that restricted observations are not included in these files, and dewpoint will only be displayed if the station reports a temperature, moisture, and pressure observation.
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
   Yes, stations can still be flagged using the embedded Google form.
3. Are RWIS sites being ingested into RTMA/URMA?
   Some RWIS sites are being ingested, but not all.  In the case of some providers (e.g., IADOT), the observations are processed through the MesoWest feed.  However, we are not currently assimilating South Dakota DOT observations.  We are working with NCO Dataflow and the EMC decoders group to bring in these additional RWIS observations.

Thanks,
Matt

On Wed, May 24, 2023 at 10:02 AM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

RTMA/URMA group,

  There's been a persistent low dewpoint area in north central Iowa, about 25 miles or so south of Clear Lake Iowa.  When trying to figure out the cause, I think I have identified the root cause as being an RWIS site. See the attached image.  URMA in this area had dewpoints in the upper 30s while the general landscape had dewpoints in the mid 40s to near 50.  I have a couple questions:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
3. Are RWIS sites being ingested into RTMA/URMA?

  This general low dewpoint area has persisted for days and is being captured as part of the NBM bias correction process.

Thanks!

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

--
Andy Just RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29739415VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29746052VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29976449VLab.Notifications@noaa.gov

Hello Matt and Andy,

Yes - thanks for looking into this issue!  I would agree that those Davis stations should be removed.  

Somewhat related - is there a means for SOOs to look at this station list and data in (near) real-time? My apologies if I'm unaware?  Frankly, I'm surprised that we are allowing as many of the Davis/CWOP stations to be assimilated into RTMA.  Perhaps the "neighborhood checks" have improved to remove bad or erroneous stations?  From my experience, the maintenance of those CWOP stations is questionable, such that they eventually become problematic.   As such, an effective means of restricting them is likely needed, almost on a daily/weekly basis.  Any insight is appreciated. 

--Mike  

  

On Tue, Jun 6, 2023 at 8:12 AM Andy Just - NOAA Federal <andy.just@noaa.gov> wrote:

Matt,

  Thanks for doing this study!  I have looped in the DMX SOO who can give the approval to blacklist the problematic stations noted in the slideset.

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

On Mon, Jun 5, 2023 at 3:05 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

Please take a look at the attached slides, which are from the 20230604 12Z RTMA output.

 RTMA Dewpoint Case Study - Central Iowa

Based on my findings, the IADOT station that you identified does not appear to be responsible for the region of low dewpoints in north central Iowa.  For example, in the case examined, there is a large, negative increment in the specific humidity field, yet the observation and background values for RWII4 were 10.91 and 10.89 g/kg, respectively.

Instead, it appears that there are numerous low-biased SYNOPTIC/DAVIS stations in the area highlighted on slide 4.  Selected stations in the red box are shown in the tables on slides 5-7.  Several stations initially failed the gross-error check, but the "partial analysis" values were lowered sufficiently by the nearby stations to allow the observations to be used on subsequent outer loops; these stations are indicated in red text on slides 5-7.

Thus, my recommendation would be to add all of the stations listed in the tables, with the exception of RWII4, to the reject list for moisture.  We ran a quick test case that confirms this should help address the issue.  Then, we can keep an eye on the analysis to see if it improves and if any additional stations need to be rejected.  However, we would need to have this approved by the local forecast office (DMX) before we proceed.

Thanks,

Matt

On Wed, May 24, 2023 at 4:31 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

We will take a closer look at the dew point analyses in this area and follow-up with you soon.  In the meantime, please see my answers to your other questions below:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
   We don't have a site currently that lists the observations going into RTMA/URMA.  However, we do have KML observation files available here.  These can be viewed in Google Earth.  However, please note that restricted observations are not included in these files, and dewpoint will only be displayed if the station reports a temperature, moisture, and pressure observation.
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
   Yes, stations can still be flagged using the embedded Google form.
3. Are RWIS sites being ingested into RTMA/URMA?
   Some RWIS sites are being ingested, but not all.  In the case of some providers (e.g., IADOT), the observations are processed through the MesoWest feed.  However, we are not currently assimilating South Dakota DOT observations.  We are working with NCO Dataflow and the EMC decoders group to bring in these additional RWIS observations.

Thanks,
Matt

On Wed, May 24, 2023 at 10:02 AM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

RTMA/URMA group,

  There's been a persistent low dewpoint area in north central Iowa, about 25 miles or so south of Clear Lake Iowa.  When trying to figure out the cause, I think I have identified the root cause as being an RWIS site. See the attached image.  URMA in this area had dewpoints in the upper 30s while the general landscape had dewpoints in the mid 40s to near 50.  I have a couple questions:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
3. Are RWIS sites being ingested into RTMA/URMA?

  This general low dewpoint area has persisted for days and is being captured as part of the NBM bias correction process.

Thanks!

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

--
Andy Just RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29739415VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29746052VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29976449VLab.Notifications@noaa.gov

--

--
Michael Fowle
Science and Operations Officer

National Weather Service
Des Moines, Iowa
Tel 515.270.4501 ext 766
http://www.weather.gov/desmoines

Hi Mike,

Thanks for confirming the stations should be added to the reject list.  We will let you know once the change takes effect.

In order to view the observations being used, I would suggest using the URMA KML observation files available here.  These can be viewed in Google Earth.  However, please note that restricted observations are not included in these files, and dewpoint will only be displayed if the station reports a temperature, moisture, and pressure observation.  KML files containing the restricted obs can be shared upon request using Kiteworks.

The values in the slide deck were all pulled from the 20230604 12Z RTMA KML file.  We currently only upload the URMA KML files, though.

Thanks,
Matt

On Tue, Jun 6, 2023 at 12:05 PM Michael Fowle - NWS Federal <michael.fowle@noaa.gov> wrote:

Hello Matt and Andy,

Yes - thanks for looking into this issue!  I would agree that those Davis stations should be removed.  

Somewhat related - is there a means for SOOs to look at this station list and data in (near) real-time? My apologies if I'm unaware?  Frankly, I'm surprised that we are allowing as many of the Davis/CWOP stations to be assimilated into RTMA.  Perhaps the "neighborhood checks" have improved to remove bad or erroneous stations?  From my experience, the maintenance of those CWOP stations is questionable, such that they eventually become problematic.   As such, an effective means of restricting them is likely needed, almost on a daily/weekly basis.  Any insight is appreciated. 

--Mike  

  

On Tue, Jun 6, 2023 at 8:12 AM Andy Just - NOAA Federal <andy.just@noaa.gov> wrote:

Matt,

  Thanks for doing this study!  I have looped in the DMX SOO who can give the approval to blacklist the problematic stations noted in the slideset.

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

On Mon, Jun 5, 2023 at 3:05 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

Please take a look at the attached slides, which are from the 20230604 12Z RTMA output.

 RTMA Dewpoint Case Study - Central Iowa

Based on my findings, the IADOT station that you identified does not appear to be responsible for the region of low dewpoints in north central Iowa.  For example, in the case examined, there is a large, negative increment in the specific humidity field, yet the observation and background values for RWII4 were 10.91 and 10.89 g/kg, respectively.

Instead, it appears that there are numerous low-biased SYNOPTIC/DAVIS stations in the area highlighted on slide 4.  Selected stations in the red box are shown in the tables on slides 5-7.  Several stations initially failed the gross-error check, but the "partial analysis" values were lowered sufficiently by the nearby stations to allow the observations to be used on subsequent outer loops; these stations are indicated in red text on slides 5-7.

Thus, my recommendation would be to add all of the stations listed in the tables, with the exception of RWII4, to the reject list for moisture.  We ran a quick test case that confirms this should help address the issue.  Then, we can keep an eye on the analysis to see if it improves and if any additional stations need to be rejected.  However, we would need to have this approved by the local forecast office (DMX) before we proceed.

Thanks,

Matt

On Wed, May 24, 2023 at 4:31 PM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

Hi Andy,

We will take a closer look at the dew point analyses in this area and follow-up with you soon.  In the meantime, please see my answers to your other questions below:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
   We don't have a site currently that lists the observations going into RTMA/URMA.  However, we do have KML observation files available here.  These can be viewed in Google Earth.  However, please note that restricted observations are not included in these files, and dewpoint will only be displayed if the station reports a temperature, moisture, and pressure observation.
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
   Yes, stations can still be flagged using the embedded Google form.
3. Are RWIS sites being ingested into RTMA/URMA?
   Some RWIS sites are being ingested, but not all.  In the case of some providers (e.g., IADOT), the observations are processed through the MesoWest feed.  However, we are not currently assimilating South Dakota DOT observations.  We are working with NCO Dataflow and the EMC decoders group to bring in these additional RWIS observations.

Thanks,
Matt

On Wed, May 24, 2023 at 10:02 AM VLab Notifications <VLab.Notifications@noaa.gov> wrote:

RTMA/URMA group,

  There's been a persistent low dewpoint area in north central Iowa, about 25 miles or so south of Clear Lake Iowa.  When trying to figure out the cause, I think I have identified the root cause as being an RWIS site. See the attached image.  URMA in this area had dewpoints in the upper 30s while the general landscape had dewpoints in the mid 40s to near 50.  I have a couple questions:

1. Is there a site that dynamically allows us to see the observations going into RTMA/URMA?
2. Can we still blacklist sites, via https://vlab.noaa.gov/group/715073/observation-qc-requests 
3. Are RWIS sites being ingested into RTMA/URMA?

  This general low dewpoint area has persisted for days and is being captured as part of the NBM bias correction process.

Thanks!

Andrew Just

ForecastBuilder Manager

Techniques Development Meteorologist

NWS Central Region Headquarters STI

816-550-7324

--
Andy Just RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29739415VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29746052VLab.Notifications@noaa.gov

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758

--
Matthew Morris RTMA/URMA Discussion Group Virtual Lab Forum http://vlab.noaa.gov/web/715073/home/-/message_boards/view_message/29976449VLab.Notifications@noaa.gov

--

--
Michael Fowle
Science and Operations Officer

National Weather Service
Des Moines, Iowa
Tel 515.270.4501 ext 766
http://www.weather.gov/desmoines

--

Matthew Morris

SAIC at NOAA/NWS/NCEP/EMC

5830 University Research Ct., Rm. 2038

College Park, MD 20740

301-683-3758