JEFS Status Report
Department of Atmospheric Sciences
University of Washington
Cliff Mass, Jeff Baars, David Carey
JEFS Workshop, August 28-29
Who is working on JEFS at the
UW?

Atmospheric Sciences





Cliff Mass-main faculty lead
Jeff Baars-research scientist
David Carey-research scientist
Some assistance from other staff
Statistics




Tilmann Gneiting-main faculty lead.
McClean Sloughter-grad student working on precip and
wind bma
Chris Fraley-staff, software support
Some assistance from Adrian Raftery-Prof--Mr. BMA
The Two Basic Requirements for
Post Processing of JEFS
Forecasts are:
Quality controlled observational data
for the region of interest of all
necessary parameters
 Reliable JME grids for several
months at least.

Acquiring and QCing JEFS Obs
Data
 Not
in the Statement of Work
(SOW), but a critical requirement
for JEFS.
 Developed a robust QC system at
the UW that has been tested over
the last year and recently
transferred to AFWA.
UW Observation Quality Control
System




Range Check
 A simple gross error check to make sure the observation is
within a reasonable range.
Step Check
 Looks for "spikes" in an station's time series for a given
variable.
Persistence Check
 Looks for variables that are not changing over extended
periods, indicative a failed or frozen sensor.
Spatial Check
 Compares each observation to those of surrounding
stations. Specifically, designed to handle areas of complex
terrain-like Korea and the NW U.S.
Quality Control Display and
Warning System
This system is now working on the UW
Northwest test bed for a heterogeneous
collection of roughly 70 different networks.
 View it in real time at:

http://www.atmos.washington.edu/~qcreport/
JEFS Observations
Recently began receiving observations for
3-, 6-, and 12-hr precipitation.
 …in addition to temperature, dew point,
altimeter, sea level pressure, wind speed
and direction.
 Now receiving Korean Mesonet Data.
 Format of obs still being adjusted…

Forecast Verification
Another major issue is to have forecast
verification code running operationally,
since that is essential infrastructure for postprocessing.
 UW has developed code called “verobs”
which is being transferred to AFWA

UW-to-AFWA Code Transfers for
QC and forecast verification


Observations Quality Control Fortran code
transferred to Scott Rentschler at AFWA, March
2007.
 AFWA needs to use this software to flag and
remove observations from the collection we are
receiving.
Forecast verification Fortran code, “verobs,”
transferred to Scott Rentschler at AFWA, August
2007.
Next Item: Bias Correction
Software Development and
Transfer to AFWA

As noted many times in the past, bias
correction substantially improves
probabilistic prediction since
systematic bias does not represent true
uncertainty.
Bias Correction of T2 and TD2

Have bias correction running in real-time for 2-m
temperature and 2-m dew point temperature for
the UW Mesoscale Ensemble System (UWME).
 Uses optimized settings.
 Have gotten this running on the JME/WRF
output as well, using “older generation” JME
model data.
 Results shown at JEFS technical meeting, Sep2006.
 Ready to transfer code to AFWA.
Bias Correction of PCP12

Have developed bias correction settings for 12-hr
precipitation for the UWME.
 As with T2 and TD2, settings were determined
through an optimization process.
 Removed land use in gridpoint – to – obs
matching; using bins for precipitation amount
 Included in Weather and Forecasting paper,
along with T2 and TD2.
 Results look good…
Results: Bias Corrected PCP12,
forecast hour 48, 2004-July to 2005June, using UWME system
Metric
Uncorrected Bias
Corrected
Mean
Absolute
Error
(inches)
0.060
0.046
Mean Error
(inches)
0.018
-0.013
Help
Fraction
N/A
0.133
Hurt
Fraction
N/A
0.047
Daily Domain
Averaged ME
for PCP12, f48,
December 2004
Daily Domain
Averaged MAE
for PCP12, f48,
December 2004
Daily Domain
Averaged ME
for PCP12, f48,
October 2004
Daily Domain
Averaged MAE
for PCP12, f48,
October 2004
Local Bias Correction of DIR10
and SPD10

Currently working on 10-m winds.
 As with T2 and TD2, a statistically significant
correlation between model error and land use
appears to exist, especially for wind speed.
Next Issue: Transferring BMA to
AFWA




Local BMA for temperature is now working
operationally over the Northwest and is ready to be
transferred to AFWA. FORTRAN Code.
Same approach can be used for dew point temperature.
Global BMA is working for precipitation. Currently
written in “r” and must be converted to FORTRAN
before it can be transferred to AFWA (Jeff Baars is doing
this now).
Local BMA for precipitation and BMA for wind has
been an area of active work between atmos sci and
statistic and prototypes are working, but still being
improved and evaluated. The next talk will describe this
more.
We have continued to maintain
and improve PROBCAST
Probcast is our attempt to package
uncertainty data in a form accessible to
laymen and less experienced forecasters.
 A version of probcast will be adapted for
DOD use when the underlying JEFS system
is in place.
 Are now extending the verification of
Probcast over the NW.

Before Probcast: The BMA Site
PROBCAST
Verification of Probcast temperatures web tool
Next: McClean Sloughter, UW
Statistics