NWS Forecast Office Assessment of GOES Sounder Atmospheric Instability

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NWS Forecast Office Assessment of GOES Sounder
Atmospheric Instability
Summer 99 Forecaster assessment of usefulness of
changes in hourly LI, CAPE, CINH product for
predicting location/timing of thunderstorms
There were 248 valid weather cases. -
Significant Positive Impact (30) - Slight
Positive Impact (49) - No Discernible Impact
(19) - Slight Negative Impact (2) - Significant
Negative Impact (0)
Figure from the National Weather Service, Office
of Services
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NWS Forecast Office Assessment of GOES Sounder
Total Precipitable Water
Summer 99 Forecaster assessment of usefulness of
changes in hourly TPW product for precipitation
forecast Out of 207 weather cases. - Significant
Positive Impact (21.3) - Slight Positive Impact
(50.2) - No Discernible Impact (27) - Slight
Negative Impact (1) - Significant Negative
Impact (Figure from the National Weather Service, Office
of Services
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3h 20km RUC cloud-top fcst w/ GOES cloud
assimilation
Verification Cloud-top pressure based on NESDIS
product
Effect of GOES (sounder cloud) data on 3-h RUC
cloud forecasts much improved cloud forecasts
1800 UTC Tues 2 Oct 2001
Stan Benjamin NOAA/FSL
3h 40km RUC cloud-top fcst No GOES cloud
assimilation
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40km RUC
20km RUC w/ cloud analysis
3h 20km RUC cloud-top fcst w/ GOES cloud
assimilation
Verification Cloud-top pressure based on NESDIS
product
Stan Benjamin NOAA/FSL
Cloud-top forecast verification - correlation
coefficient between forecast and
NESDIS cloud-top product - much improved cloud
forecasts even at 12h 28 Sept 2 Oct 2001
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Eta Data Assimilation System Satellite Data
Impact Study for 3 Seasons
Positive Impact due to GOES sounder PW
(marine) Positive Impact due to Radiosonde (T and
moisture)
Ratio
A Ratio greater than 1 means the satellite
improved the forecast more than the
radiosondes over the entire domain (land and
marine)
24-hr forecast for Temperature
24-hr forecast for Relative Humidity
In 80 km Eta Data Assimilation System (EDAS),
impact of GOES Sounder marine products versus
conventional RAOB information was tested. In
summer, Sounder has larger positive impact on
temperature and moisture forecasts than
conventional RAOB.
Data Assimilation -- Data Denial
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Data Assimilation -- Satellite Data Improving
Forecasts
Positive forecast impact () of both GOES and
POES data in the EDAS (Eta Data
Assimilation/Forecast System) on standard
meteorological state variables for the seasons
thus far evaluated (fall 2001 and winter
2001/2002).
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Satellite winds on GFDL Forecasts
GOES-8 1km visible
Soden et al.
Former National Hurricane Center director Robert
Sheets once said that if he had only one tool to
do his forecasting job, it would be the
geostationary weather satellite.
http//www.usatoday.com/weather/news/2000/w330s
atann.htm