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NAM Upgrade Graphics


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For anyone here interested, the NAM "parallel" run is available for use. There are graphics for both the operational NAM, the new NAM coming in July, and a comparison of the two. Just loooking at the latest runs today, the new NAM (parallel) seems closer to global guidance (CMC, GFS, ECMWF) near the end of the period than the operational NAM, especially with the strong PV anomaly rotating the base of the mean western trough into Alberta after 60 hrs. Notice how much deeper the parallel run is w.r.t. the operational NAM--which is a closer fit to the global guidance. Personally I have high hopes for the new upgraded NAM, which from what I have read, almost seems like a brand new numerical model. Hopefully we won't be saying, "It is only the NAM being the NAM" in the future.

http://www.emc.ncep....ll/nampll_nmmb/

post-999-0-42394000-1308186105.gif

Link for those not in the know regarding the NAM upgrade:

http://www.americanw...es-this-summer/

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I think you can also get the parallel NAM run graphics at http://www.nco.ncep.noaa.gov/pmb/nwpara/analysis/

For anyone here interested, the NAM "parallel" run is available for use. There are graphics for both the operational NAM, the new NAM coming in July, and a comparison of the two. Just loooking at the latest runs today, the new NAM (parallel) seems closer to global guidance (CMC, GFS, ECMWF) near the end of the period than the operational NAM, especially with the strong PV anomaly rotating the base of the mean western trough into Alberta after 60 hrs. Notice how much deeper the parallel run is w.r.t. the operational NAM--which is a closer fit to the global guidance. Personally I have high hopes for the new upgraded NAM, which from what I have read, almost seems like a brand new numerical model. Hopefully we won't be saying, "It is only the NAM being the NAM" in the future.

http://www.emc.ncep....ll/nampll_nmmb/

post-999-0-42394000-1308186105.gif

Link for those not in the know regarding the NAM upgrade:

http://www.americanw...es-this-summer/

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The NAM (the most at least) has been doing extremely well down here in West Texas for the past 2-3 months so I'm a little sad to see a change made, selfishly. The GFS has been absolutely horrid and practically unusable with temperature MAEs of near 7 degrees over the past 30+ days. Who knows, maybe the newer NAM will be even better.

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The NAM (the most at least) has been doing extremely well down here in West Texas for the past 2-3 months so I'm a little sad to see a change made, selfishly. The GFS has been absolutely horrid and practically unusable with temperature MAEs of near 7 degrees over the past 30+ days. Who knows, maybe the newer NAM will be even better.

NAM's definitely been picking up on the drought better in TX... often being 5+ degrees warmer than the GFS and verifying that high or warmer. Would be interesting to see what #s the new NAM MOS is putting out for that area... maps look relatively similar.

Here's the maps for 21z 6/16:

post-96-0-25525500-1308201547.gif

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The NAM (the most at least) has been doing extremely well down here in West Texas for the past 2-3 months so I'm a little sad to see a change made, selfishly. The GFS has been absolutely horrid and practically unusable with temperature MAEs of near 7 degrees over the past 30+ days. Who knows, maybe the newer NAM will be even better.

Are you referring to GFS MOS products for 2m T? Some other (more raw) model output? Did you notice similar behavior prior to the May 9 upgrade (which included changes to the thermal roughness length....which had an impact on near surface temperature forecasts)?

Sorry for all the questions, but documenting these kinds of things helps us out moving forward.

As an aside, NAM parallel verification (last 3 weeks) can be found at: http://www.emc.ncep.noaa.gov/mmb/mmbpll/mmbverif.namplls/ [including region specific surface verification].

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For anyone here interested, the NAM "parallel" run is available for use. There are graphics for both the operational NAM, the new NAM coming in July, and a comparison of the two. Just loooking at the latest runs today, the new NAM (parallel) seems closer to global guidance (CMC, GFS, ECMWF) near the end of the period than the operational NAM, especially with the strong PV anomaly rotating the base of the mean western trough into Alberta after 60 hrs. Notice how much deeper the parallel run is w.r.t. the operational NAM--which is a closer fit to the global guidance. Personally I have high hopes for the new upgraded NAM, which from what I have read, almost seems like a brand new numerical model. Hopefully we won't be saying, "It is only the NAM being the NAM" in the future.

http://www.emc.ncep....ll/nampll_nmmb/

post-999-0-42394000-1308186105.gif

Link for those not in the know regarding the NAM upgrade:

http://www.americanw...es-this-summer/

Good. It's about time... I know you were not a fan of the NAM last winter.

Another thing I'm hoping from the new NAM is the ability to do well past 48hrs... outside of that time it was basically trash.

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Are you referring to GFS MOS products for 2m T? Some other (more raw) model output? Did you notice similar behavior prior to the May 9 upgrade (which included changes to the thermal roughness length....which had an impact on near surface temperature forecasts)?

Sorry for all the questions, but documenting these kinds of things helps us out moving forward.

As an aside, NAM parallel verification (last 3 weeks) can be found at: http://www.emc.ncep....bverif.namplls/ [including region specific surface verification].

dtk, I wasn't even aware that a change was implemented on May 9 (the communication via national PNS is often less than desireable). It would be difficult to assess anyway as we were not yet in the gruesome pattern that we are currently seeing. That said, I have noticed the GFS MOS temps showing a cold bias since late last summer (when I first arrived at SJT).

At San Angelo we are seeing cold biases on the order of -5 to -8 degrees F averaged over the past 30+ days. The NAM biases are typically -2 or better. I'm sure the drought and lack of soil moisture isn't helping at all but its frustrating to sit down at the grids and have useless guidance. Persistence, NAM and HPC are blowing it out of the water.

I am referring to the MaxT/MinT GFS MOS output (which I assume is based on the 2m temps).

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Good. It's about time... I know you were not a fan of the NAM last winter.

Another thing I'm hoping from the new NAM is the ability to do well past 48hrs... outside of that time it was basically trash.

It has a long way to go, but analyzing the new parallel run for a couple days has me seriously hopeful that many of the crippling aspects of the old NAM have been fixed. I truly believe this will be a big improvement.

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  • 2 weeks later...
  • 4 weeks later...

Got this by e-mail just now.

Hi all,

EMC and NCO have worked together to resolve the issues which led to our stopping the 30-day evaluation of the NAM last month.  Effective with the 12Z run tomorrow, August 3, we are restarting the clock on the 30-day evaluation of the NAM NMM-B upgrade.  The 30-day period will end on Sep. 2.  I will need evaluation slides back as early as possible the week of Sep. 5, if not sooner.  I hope to be briefing Dr. Uccellini later that week so we can implement on Sep. 13.    As usual, please let me know if you have any questions.  Thanks for your patience and understanding re: testing of this important upgrade.

Thanks,

Chris

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Just got another email.

Hi All,

Due to a compile glitch, the code that updates snow cover/depth in the parallel NDAS was aborting in the NCO parallel run. When this happens, the NDAS will just cycle snow continuously based on the model predicted snowfall in the 3-h NDAS forecasts. This problem started approximately in mid/late June.   The affected codes were just recompiled correctly yesterday.

NCO also received user requests to save and alert the fire weather center points and to include additional GEMPAK parameters for HPC.  Because we are making these 3 changes, we decided to restart the 30-day evaluation for the NAM NMM-B in order to give all evaluators the benefit of having the full period to evaluate these changes.  Additional info re: the location of the fire weather points will be made available as soon as possible.    The 30-day evaluation period restarts with the 00Z run on Aug. 11 and will end on Sep. 10.  We expect to implement the NAM NMM-B on Sep. 20.

Please let me know if you have any questions.

Thanks,

Chris

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Just got another email.

Hi All,

Due to a compile glitch, the code that updates snow cover/depth in the parallel NDAS was aborting in the NCO parallel run. When this happens, the NDAS will just cycle snow continuously based on the model predicted snowfall in the 3-h NDAS forecasts. This problem started approximately in mid/late June. The affected codes were just recompiled correctly yesterday.

NCO also received user requests to save and alert the fire weather center points and to include additional GEMPAK parameters for HPC. Because we are making these 3 changes, we decided to restart the 30-day evaluation for the NAM NMM-B in order to give all evaluators the benefit of having the full period to evaluate these changes. Additional info re: the location of the fire weather points will be made available as soon as possible. The 30-day evaluation period restarts with the 00Z run on Aug. 11 and will end on Sep. 10. We expect to implement the NAM NMM-B on Sep. 20.

Please let me know if you have any questions.

Thanks,

Chris

Geez, I wish they would just make the switch now and junk the current NAM. The parallel run has been a vast improvement to the old NAM, and it is about time the old NAM goes the way of the NGM, LFM, etc.

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The NAM and GFS now have the same appearance-- no super squiggly lines with the NAM. What's up with that?

post-1182-0-10082700-1313445161.jpg

Ouch... They seriously hyper-smoothed the NAM maps too? I gotta add the NAM to my site lol... I've placed the real, full-resolution GFS map below (notice especially the lower "blurriness" in the precipitation amounts)

usapcpthkprs1000500mb02.gif

Source: http://instantweathermaps.com/GFS-php/showmap-conusncep.php?run=2011081512&var=PCPTHKPRS_1000-500mb&hour=024

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The NAM and GFS now have the same appearance-- no super squiggly lines with the NAM. What's up with that?

nam_gfs.JPG

Ouch... They seriously hyper-smoothed the NAM maps too? I gotta add the NAM to my site lol... I've placed the real, full-resolution GFS map below (notice especially the lower "blurriness" in the precipitation amounts)

<irrelevant image removed>

Source: http://instantweathe...-500mb&hour=024

Let's just hope they don't hypersmooth the HRW... can someone say FAIL? And by the way, Twister Data also doesn't hypersmooth (though TD does use the low-res data for hours 204-384 of the GFS... your site is the only one I've seen that uses the full 1.0-degree resolution). Yes, you do need to add the NAM... put that fancy new dedicated server to work!

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  • 3 weeks later...

Conference call happening right now... updated NAM has severe under-strength and under-convection issues, also cold bias in CONUS in winter... Eastern region NWS guy saying original NAM is better. 4km CONUS nest doesnt have the under-convection bias. Bias especially shows up in omega values. HPC survey says un-updated better in winter, updated w/nest best in spring, updated w/o nest worst by far in spring. Everyone recommends implementation though due to better handling of synoptic tracks and removal of over-convective feedback. SPC says nest worse than HRW due to extremely low updraft speeds. They recommend focused improvement rather than implementation. New NAM is a chicken with mesoscale/microscale storms. Vertical velocity 700-500mb a severe lower outlier.

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Conference call happening right now... updated NAM has severe under-strength and under-convection issues, also cold bias in CONUS in winter... Eastern region NWS guy saying original NAM is better. 4km CONUS nest doesnt have the under-convection bias. Bias especially shows up in omega values. HPC survey says un-updated better in winter, updated w/nest best in spring, updated w/o nest worst by far in spring. Everyone recommends implementation though due to better handling of synoptic tracks and removal of over-convective feedback. SPC says nest worse than HRW due to extremely low updraft speeds. They recommend focused improvement rather than implementation. New NAM is a chicken with mesoscale/microscale storms. Vertical velocity 700-500mb a severe lower outlier.

Whoops

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Conference call happening right now... updated NAM has severe under-strength and under-convection issues, also cold bias in CONUS in winter... Eastern region NWS guy saying original NAM is better. 4km CONUS nest doesnt have the under-convection bias. Bias especially shows up in omega values. HPC survey says un-updated better in winter, updated w/nest best in spring, updated w/o nest worst by far in spring. Everyone recommends implementation though due to better handling of synoptic tracks and removal of over-convective feedback. SPC says nest worse than HRW due to extremely low updraft speeds. They recommend focused improvement rather than implementation. New NAM is a chicken with mesoscale/microscale storms. Vertical velocity 700-500mb a severe lower outlier.

Ouch...

Hey wait how did you get into a NOAA conference call?

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