Mesoscale Modeling Project at NWS Melbourne, Florida
BACKGROUND
Applied
Meteorology Unit (AMU) entities, comprised of personnel from the Melbourne,
FL National Weather Service (NWS) Weather Forecast Office (WFO
MLB) AMU, the NWS Spaceflight
Meteorology Group (SMG) in Houston, TX, and ENSCO, Inc.), implemented
a Local Data Integration
System (LDIS) at WFO Melbourne and
SMG
Houston between late 2000 and early 2001. This effort was undertaken
to integrate the various data sets in proximity to the Kennedy Space Center
(KSC) and east-central Florida, and to generate products that may enhance
short-range (less than 6-hr) forecasts. LDIS analyses allow forecasters to
quickly examine many disparate data sets within a single framework, to
assist in assessing local weather changes in a high temporal and
geographic resolution.
Efforts during 2003 and 2004 built upon the earlier LDIS work to
configure a mesoscale prognostic model, using LDIS analyses to improve
the model initialization. WFO MLB forecasters now routinely
examine real time LDIS analyses and mesoscale prognostics upon the
Advanced Weather Interactive Processing System (AWIPS),
the primary NWS meteorological data integration system. With the porting of output to AWIPS,
direct comparisons
can now be made between the externally generated analyses and forecasts (ADAS
and ARPS) and the AWIPS platform
packages (Local
Analysis and Prediction System; LAPS, and the Rapid Update Cycle; RUC).
In addition, the analysis and forecast fields are also available
for populating initial forecast fields within the AWIPS
Graphical Forecast Editor (GFE). LDIS analyses and forecast output can be viewed outside of AWIPS via a series of
images uploaded to the World Wide Web (WWW).
LDIS CONFIGURATION AT WFO MELBOURNE
The current configuration at WFO MLB runs on an HP 785/C3000
and uses the Advanced Regional Prediction System (ARPS) Data Analysis System
(ADAS) to generate analyses. The ADAS code was obtained from the Center
for Analysis and Prediction of Storms (CAPS) in Norman, Oklahoma. ADAS
produces analyses on a single grid with 4-km horizontal
spacing. The domain for the 4-km grid is shown in Fig. 1.
The analysis cycle is run every 15 minutes, with the start of the cycle
occurring 14 minutes after the valid time to allow retrieval of the various
data sets from remote servers, and to account for inherent latencies of
data. On average, output is available beginning 22 minutes after the actual valid
time.
REAL TIME DATA INGEST
Certain data sets available to the Melbourne forecasters are unique
when compared to what is available at other NWS offices due to the relatively
dense network of instrumentation supporting the U.S. space program in the
vicinity of Cape Canaveral. Data from the KSC meso-network (Fig.
2) include: 44 wind towers, five 915-MHz boundary-layer Doppler radar wind
profilers, and a 50-MHz radar wind profiler. Additionally, surface observations
are obtained from a network of rural agricultural sites via the University
of Florida Automated Weather Network, as well as supplemental surface
data from Automatic Position Reporting System Citizen Weather sites
which are collected and redistributed by the NOAA Forecast Systems Laboratory
(FSL). Real time Aircraft Communications Addressing and Reporting System
data is ingested to improve analyses aloft, also courtesy of FSL. These
later three data sets will be discussed in more detail below. Additional
data which are available for ingest into the LDIS include GOES-8 1-km visible
and 4-km infrared satellite imagery, METAR surface reports,
and Melbourne WSR-88D Level-II reflectivity and radial velocity fields.
The local data sets which are currently ingested into ADAS are summarized
below in Table 1.
ADAS uses 40-km Rapid Update Cycle (RUC) model forecasts
for background fields to the 4-km analyses. The RUC 1-3 hr forecasts are
linearly interpolated in time every 15 minutes to provide a background
field for the analyses.
Surface observations, KSC meso-network tower winds, profiler data, as
well as visible and infrared satellite imagery are collected for assimilation
into the ADAS every 15 minutes. These
data files originate from the NASA/NWS Spaceflight Meteorology Group (SMG)
Meteorological Interactive Data Display System (MIDDS) at the Johnson Space
Center in Houston, Texas. At present, the data are routed to the Melbourne
WFO via a server at the NWS Southern Region Headquarters in Ft. Worth, Texas,
using multiple-scheduled FTP sessions. This indirect communication process is
mandated by NASA security concerns.
Table 1: data sets currently ingested into
ADAS.
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Surface observations are also obtained from 30 rural sites via the University
of Florida Automated Weather Network (FAWN; see Fig. 3) every 15-minutes.
These sites can provide significant improvements to the background analysis
fields by adding temperature, moisture, and wind measurements from areas
removed from the traditional network of airport METAR sites. Another source of surface observations which are ingested into
the analyses include Automatic Position Reporting System (APRS; see Fig.
4) sites. These data are obtained from individuals who operate neighborhood
weather stations and distribute their observations via Amateur (ham) packet
radio and the internet. Once the APRS site configures their station for
transmission of the data to the internet and "registers" with FSL, a data
file is updated every 15 minutes for redistribution over the internet for
external use, such as ingest into the MLB ADAS.
![FAWN mesonetwork](https://webharvest.gov/peth04/20041119182536im_/http://www.srh.noaa.gov/mlb/fawn30.PNG) ![APRS mesonetwork](https://webharvest.gov/peth04/20041119182536im_/http://www.srh.noaa.gov/mlb/aprs_map_021804.PNG)
While a significant volume of the data ingest to ADAS originates near
the surface, observations from aloft are obtained as well. With the expansion
and improved distribution of the Aircraft
Communications Addressing and Reporting System (ACARS) over recent
years, this data set has become increasingly useful. ACARS data files (winds
and temperatures) are currently retrieved every 15-minutes from FSL through
the UCAResearch Unidata Local Data Manager (LDM), which is run on
a local workstation. The quantity and altitude of observations vary significantly
throughout the day. Typically, a multitude of observations are available
from around sunrise to late in the evening, with several hundred data points
ingested each analysis cycle. Conversely, a relative minima of data availability
occurs during the early morning hours. Fig. 5 provides an example of a
one hour period of wind observations encompassing the area of the ADAS domain.
![Example of acars data within the outer grid domain for 1-hour (14 February 2003)](https://webharvest.gov/peth04/20041119182536im_/http://www.srh.noaa.gov/mlb/acars_ex_021403.gif)
By combining all available surface data sets from across the Florida
peninsula, an impressive data array is obtained for model initialization.
Fig. 6 (below) depicts the current availability
of combined data sites within 4-km grid domain.
Of particular interest is the especially dense NASA tower/profiler network
and the highly beneficial FAWN observations from rural interior peninsula
locations. Observations from all the data
sets shown below are obtained with a frequency of 15-minutes or less, with
the exception of the METARs. ADAS currently ingests only routine (for top
of the hour analyses) and 'special' (when certain criteria are met) METARs.
Efforts continue to acquire an avenue for the ingest of METAR data on a 15-minute interval as well.
![Composite of surface data routinely ingested into ARPS/ADAS at NWS MLB - (4-km grid)](https://webharvest.gov/peth04/20041119182536im_/http://www.srh.noaa.gov/mlb/alldatasets021804.PNG)
An
illustration of the data flow paths to and from the WFO MLB LDIS is provided
in Fig. 7. High resolution Level-II Melbourne WSR-88D data are incorporated
into the ADAS analyses via two independent workstations. One workstation
collects the Level-II base data from the Radar Data Acquisition unit and
re-distributes it through a local Base Data Distribution Server (BDDS), designed by the National Severe Storms Laboratory. A second
workstation retrieves data from the BDDS through the LDM, using software developed
under the Collaborative Radar Acquisition Field Test (CRAFT). CRAFT allows
for the real-time compression and transmission of WSR-88D base data across
the Internet. The file system containing the Level-II data ingested by
LDM is mounted so that the workstation running ADAS can access and re-map
the radar data to each analysis grid. Satellite files and NASA mesonet data are retrieved from SMG via a server at SRH. ACARS
and APRS data files are obtained from FSL through the SRH frame relay. FAWN
data files are obtained from a UF server via FTP and the RUC 1-3 hour forecasts
for background initialization are obtained from the NWS Telecommunications
Gateway server. ADAS analyses are converted to NetCDF format for ingest into
the AWIPS Local Data Acquisition and Dissemination
(LDAD) and displayed upon AWIPS workstations. External distribution to the WWW in Graphics Interchange Format
(GIF) takes place upon another workstation.
MESOSCALE PROGNOSTICS
During the first half of 2003, WFO MLB acquired and configured a
10-node, 20-processor Linux cluster to run the numerical weather prediction
model ARPS (Advanced Regional Prediction System). The current hardware provides
for the generation of a 0 to 9 hour forecast with a processing and graphic
generation time of 3.5 h. The 9-hour forecast length was chosen to maximize the
frequency of forecast updates with fresh ADAS observational analyses under the
current hardware constraints. Four ARPS runs are initialized each day at 03, 09,
15 and 21 UTC. The ARPS output is on the same 177 by 177 domain and 4-km
horizontal resolution as ADAS. The model contains 45 vertical levels and current
post-processing strategies produce a temporal resolution of 30 min. Model output
is post processed as forecast increments are finished, providing guidance to the
forecaster as timely as possible.
The MLB ARPS uses the 3-12 hour, 40-km RUC forecast as its background field and
lateral boundary conditions. At the start of each model run, an Intermittent
Data Assimilation (IDA) cycle is completed. The IDA cycle incorporates
observational data into the ARPS model by alternating between ADAS analyses that
initialize very short range ARPS forecasts over a specified time interval (Case
2003). The IDA is typically run over a one hour pre-forecast period, but can be
adjusted to any length of time. An IDA strategy has
been instituted to start the ARPS forecast model with as much mesoscale detail
as possible. At the start of the IDA, the RUC 2-h forecast is used as the first
guess field for the initial ADAS. This first ADAS analysis is then used to
initialize a short 15 min ARPS forecast interval. Following this 15 min forecast
interval, a second ADAS analysis is generated with a complete set of new
observational data and uses the ARPS 15 min forecast as its first guess field.
This process of generating new ADAS analyses and then 15 min ARPS forecasts
continues through the entire IDA cycle. The last ADAS analysis is used to
initialize ARPS as it begins the 9-hour forecast.
Since July 2003, ARPS has been run routinely at WFO Melbourne, in an experimental mode. Selected
forecast fields are created and posted to a WWW page, with a temporal
resolution of 30 min. By early 2004, prognostic output began to be ported
routinely to AWIPS as it become available, with a time resolution of 1-hour. Forecast fields
are
also available for 'first-guess' populating of AWIPS GFE forecast grids.
Below are some of the noteworthy milestones achieved to date:
-
Assessment of hardware & data ingest requirements for ADAS begins -
early 2000
-
ADAS software loaded and configured at NWS Melbourne - Oct. 2000
-
GOES VIS & IR data ingested from NWS Southern Region Headquarters (SRH)
- Oct. 2000
-
RUC 40-km 3-12 hour forecasts ('isobaric coordinate') ingested via SRH - Oct. 2000
-
GOES, METAR, & NASA mesonet data ingested from SMG via SRH server -
Dec. 2000
-
GARP configured to view ADAS output - Dec. 2000
-
KMLB Level II Refl. & Vel. data from RUDDS ingested via LDM/CRAFT -
Mar. 2001
-
RUC switched to 'hybrid coordinate' and ingested via NWS OSO server - May
2001
-
Surface temp. fields improved & full temp. profiles from NASA tower
winds ingested - June 2001
-
FAWN data ingested - July 2001
-
ACARS data received from FSL via LDM and ingested - Aug. 2001
-
Began routine production & uploading of analysis graphics to MLB web-page
- Aug. 2001
-
APRS data received from FSL and ingested - Sept. 2001
-
ADAS output ported to MLB AWIPS - March 2002
-
Added Java Script animation capability to web-page for viewing analyses
- Aug. 2002
-
Changed RUC background fields to 40-km 1-3 hour forecasts - Dec. 2002
-
Expanded analysis domain and changed nested 10km/2km grids to single 4km grid -
Dec. 2002
-
Expanded production of analysis graphics available on the MLB web-page - Dec.
2002
-
Acquired linix cluster for running mesoscale prognostics (March 2003)
-
Began routine generation of experimental ARPS mesoscale model output (July 2003)
-
ARPS output ported to MLB AWIPS - March 2004
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FUTURE INITIATIVES
![](https://webharvest.gov/peth04/20041119182536im_/http://www.srh.noaa.gov/mlb/newdatasets.PNG) The configuration of ADAS and the routine generation of real-time analyses
were completed at the Melbourne NWS office during the spring of 2001. A post-configuration AMU task
conducted during 2002 and 2003 involved familiarizing the entire operational
staff with using the integrated data analysis package to support various
forecast programs. During this time, analysis fields continued to be examined in
an operational environment, and optimization of the ADAS configuration
package was performed to improve reliability and operational usefulness. In
addition, GEMPAK and GARP scripts were customized further to offer greater
display functionality. These efforts prepared forecasters for assimilating
current conditions following an organized process, as opposed to viewing
disparate data sets and integrating them manually to form a mental picture
of the atmosphere.
During the next year, integrating WSR-88D Level-II data from surrounding sites, initially
Miami, then Jacksonville and Tampa (and perhaps Tallahassee and Key West) will
be pursued to help provide additional low-level velocity
and reflectivity data within ADAS domain. Additional data sets will be evaluated for potential inclusion
into the ADAS analyses (e.g. intermediate METARs, GPS
IPW, WFO Miami Handar sites, CMANs, USF Comps data, forestry RAWS data, FDOT
RWIS sites, and observations from the new Seminole county mesonet). Increased bandwidth is also sought to allow receipt of improved
resolution background fields (e.g. transition to the 20-km RUC, from the 40-km
RUC). In addition, a new LINUX workstation has been procured, to allow
expansion of the ADAS/ARPS grid domains to cover the entire state of
Florida, currently planned for mid 2004. In addition, a second new
workstation will allow for faster generation of analyses and forecasts
for the WWW, and for an expansion of the graphical product suite (e.g.
current and forecast conditions, meteograms, etc.). Also, the version
of ARPS being run at WFO Melbourne will be transitioned to the most
recent version of the software. One advantage of the latest ARPS
software is more efficient code which should allow forecasts to
complete in less time, and therefore become even more operationally
useful. Finally, both ADAS and ARPS output will be examined closely
and compared to ground-truth, and efforts will be made to modify
adaptable parameters to further improve accuracy.
EARLY EXAMPLES
RELATED WFO MELBOURNE PUBLICATIONS & PRESENTATIONS
Local data integration over East-Central Florida using the ARPS data analysis
system
An
operational Local Data Integration System (LDIS) at NWS Melbourne
Local
data analysis on AWIPS at NWS Melbourne, FL
Using
high-resolution diagnostics to facilitate the short-term threat assessment of
tornadoes during Tropical Storm Gabrielle (2001)
High resolution
diagnostics and short term prognostics in support of fire weather operations at
NWS Melbourne, FL (pdf)
High resolution
diagnostic and short term prognostics in support of weather forecast and warning
operations at NWS Melbourne, FL (pdf)
High-resolution model simulations of tornadic storms over Florida
during Tropical Storm Gabrielle (2001) (pdf)
Local
data integration and generation of mesoscale analyses and prognostics
at WFO MLB
The NWS
Southern Region modeling initiative at WFO Melbourne, FL (pdf)
NWS utilization of the ARPS/LDIS Analysis System for short-term
forecasting in east-central Florida
Radar
characteristics of mesocyclones associated with tropical cyclones (TC)
and a simulation of the mesocyclone characteristics using MM5 (pdf)
A
real-time configuration of the ARPS Data Analysis System to support
operational forecasting in east-central Florida
Utilizing a local data assimilation and prognostic system to aid with
the timing, placement, and impact of short-range tropical weather
hazards (pdf)
For
questions, comments, and feedback concerning the Mesoscale Modeling Project
at NWS Melbourne, please email Scott
Spratt or Pete
Blottman or Dave
Sharp. |