TAMDAR Project April Boulder Meeting

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TAMDAR Project April Boulder Meeting
Ed Szoke NOAA Forecast Systems Laboratory

Joint collaboration with the Cooperative
Institute for Research in the Atmosphere,
Colorado State University, Fort Collins, CO
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Overview

• Assessing TAMDAR data quality
• Method
• Compare TAMDAR soundings with each other
• Compare to nearby ACARS soundings (for T)
• Compare to a verifying raob sounding
• Concentrated on DTW and MSP
• Also looked at MEM when CLASS soundings were
  present

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Example 1 7 March 05/1200 UTC

• A look at some TAMDAR soundings
• A large variation in quality of this sounding
  sample
• Some from MSP, some compared to CIMMS soundings
  in MEM

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Weather on 7 March NW flow, scattered snow
showersat 1100 UTC at MSP

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TAMDAR soundings with raob comparison at
MSP-sharp inversion
While there is quite a bit of variability
(possibly the time differences could account for
some of this), the sharp inversion is well
captured.
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TAMDAR soundings with raob comparison at MSP
Raob is in green again. This set of soundings is
not very good.
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Weather on 7 March at MEM SW low-level flow,
scattered showers and thunderstorms at 1400 UTC
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TAMDAR soundings with CLASS soundings at Memphis
One bad sounding but overall pretty good
agreement especially with moisture.
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TAMDAR soundings with CLASS soundings at Memphis
One bad sounding again, but also more variability
in this group. But in terms of RH, the general
character of the moisture seems to be captured.
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Example 2 9 March 05/1200 UTC

• A look at some ACARS soundings
• Does a sample of ACARS soundings show good
  agreement or is it more variable like some of the
  TAMDARs?

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Weather on 9 March 05/1200 UTC Area of rain near
Memphis
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ACARS soundings out of Memphis
Very good agreement for this set close in time
and space.
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Another set of ACARS soundings out of Memphis
Good overall agreement for this set close in time
and space.
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ACARS compared to 2 TAMDAR soundings out of
Memphis
Decent agreement except for the point around 820
mb for the 1346z sounding.
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Example 3 1 April 05/1200 UTC

• Good agreement at MSP and DTW where the weather
  was dry
• More variability though at MEM where there was
  some rain in the area.

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Weather on 1 April 05/1200 UTC Wet near Memphis,
dry MSP and DTW area
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ACARS and TAMDAR soundings out of MSP
The general structure of the RH below 800 mb is
captured in the TAMDAR soundings. Temperature
agreement though is not that great.
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ACARS and TAMDAR soundings out of MSP
Overall pretty good agreement.
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TAMDAR soundings vs RAOB from DTW
All the TAMDARs do a very good job of showing the
dry layer near 800 mb.
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TAMDAR soundings vs RAOB from DTW
This set also resolves the dry layer.
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TAMDAR and ACARS soundings soundings at Memphis
Rain in the area could be the cause of more
disagreement among the soundings, but agreement
is good aob 900 mb.
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Example 4 2 April case more weather than the
last example
Radar for DTW at 1200 UTC. Detroit at the nw
edge of a major storm system to the east.

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TAMDAR soundings vs RAOB from DTW
Something goes bad with the 1223z sounding,
getting way too warm at 700 mb.
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ACARS soundings vs RAOB from DTW
Some temperature problems appear to also be found
in this set of ACARS soundings.
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TAMDAR and ACARS soundings vs RAOB from DTW
Quite a bit of spread shown in this set.
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Example 5 4 April 05/1200 UTC

• End on a good note with good agreement
• Fair weather at MSP and DTW

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Weather on 1 April 05/1200 UTC Wet near Memphis,
dry MSP and DTW area
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TAMDAR soundings vs RAOB from MSP
Excellent temperature agreement for the 1205z
sounding with a distinct low level inversion.
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TAMDAR soundings vs RAOB from MSP
Overall good agreement with both temperature and
dew point.
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TAMDAR soundings vs RAOB from MSP
Same with this set.
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TAMDAR soundings vs RAOB from DTW
Good agreement with the DTW raob key feature
here is the dry layer beginning near 800 mb.
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TAMDAR soundings vs RAOB from DTW
Good agreement, again the dry layer is well
captured.
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TAMDAR soundings vs RAOB from DTW
Same with this set.
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Summary of TAMDAR comparisons

• From comparisons since late February
• The number of questionable TAMDAR soundings
  appears to be less than in the early days of the
  project, likely a result of bad sensors being
  flagged.
• Examples demonstrated that the TAMDAR soundings
  are able to capture distinct dry and moist layers
  and sharp inversions.
• Overall, the quality appears in general to be
  good enough to be an important source of moisture
  data in the lower part of the atmosphere. Such
  information is very hard to get with any current
  sensors.