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Posted: Fri, Feb 19, 1993 3:27 PM EST Msg: NGJD-5564-4096
Subj: new asos commissioning schedule
I sent the following message on AFOS, etc. under these WMO headers:
NOUS41 KWBC
ADMN81 KWBC
NOFS11 KWBC
------------------------------------------------------------------------
WSHPNSNMC
NOUS41 KWBC 191927
NATIONAL WEATHER SERVICE HEADQUARTERS
PUBLIC INFORMATION STATEMENT
200 PM EST FRI FEB 19 1993
ATTENTION: ALL NWS OFFICES, FAMILY OF SERVICES SUBSCRIBERS,
NOAA WEATHER WIRE SERVICE SUBSCRIBERS,
OTHER NATIONAL WEATHER SERVICE PRODUCT USERS
***** NOTICE *****
The Automated Surface Observing System (ASOS) will be
commissioned by the National Weather Service at Astoria, Oregon
(call letters AST) on March 1, 1993. Commissioning of the ASOS
at this site means that ASOS has replaced the manual surface
aviation observation currently being taken at this location with
an automated surface aviation observation. However, a human
observer is still overseeing the ASOS and performing backup as
required. In addition, the Weather Service Forecast Office in
Portland, Oregon and the National Meteorological Center in
Washington, D.C. are overseeing the quality of the data.
NOTE: Because ASOS observational formats are different from
manual observational formats, automated decoder programs may
require software modifications. Persons wishing more information
concerning ASOS should contact their local National Weather
Service office or call (301) 713-1781, FAX (301) 713-0003.
END
Posted: Wed, Feb 24, 1993 4:17 PM EST Msg: AGJD-5570-4351
K.MIELKE(REC),
G.HUFFORD(REC), E.YOUNG.NWS(REC), G.TRAPP(REC)
CC: L.MILLER.UCAR(REC)
Subj: IMPLEMENTATION OF NEW REGIONAL FOG MODEL
I sent the following message on AFOS, NWWS, and the following users (via
NWSTG):
Domestic Data Service International Data Service Honolulu x.25
WMSC/FAA Canadian AES Alaksa (via WMSC)
ISPAN
-------------------------------------------------------------------------
WSHPNSNMC
NOUS41 KWBC 241937
NATIONAL TECHNICAL INFORMATION MESSAGE 93-04
NATIONAL WEATHER SERVICE HEADQUARTERS
230 PM EST WED FEB 24 1993
TO: ALL NWS OFFICES, NUMERICAL PRODUCTS SERVICE USERS,
DIRECT CONNECT SERVICE USERS
FROM: MARY M. GLACKIN
CHIEF, SERVICES DEVELOPMENT BRANCH
SUBJECT: IMPLEMENTATION OF NEW REGIONAL FOG MODEL
(THE FOLLOWING INFORMATION WAS PROVIDED BY LARRY BURROUGHS,
MARINE PREDICTION BRANCH OF THE DEVELOPMENT DIVISION OF THE
NATIONAL METEOROLOGICAL CENTER [NMC].)
Effective with the 1200 UTC cycle on Tuesday, March 2, 1993, a
Regional Fog model will be implemented. The first region to be
implemented is along the Northeast coast of the United States.
The guidance from the fog model will be available in graphical
form on AFOS (and, EVENTUALLY, in GRIdded Binary (or GRIB)
files). In the future, fog guidance for regions along the West
Coast (including the Gulf of Alaska) and the Gulf of Mexico Coast
will also be available.
To simulate the formation of fog and stratus, time dependent
changes of temperature, water vapor and liquid water content are
predicted by the fog model. It consists of a variable
horizontal region size and seven vertical layers between the
earth's surface and two kilometers. Computations are based on
standard finite difference techniques. Physical processes
included in the fog model are eddy diffusion, horizontal
advection, and fog droplet fallout. Horizontal velocity fields
in space and time for the forecast period are obtained from NMC's
Aviation Model (AVN) on both the 0000 and 1200 UTC cycles. The
AVN velocities are used to advect heat, moisture, and liquid
water. The fog model level 2 (25 meters) is the level used to
determine visual ranges and fog conditions.
Liquid water content from the fog model is converted to
visibility by an empirical formula which relates liquid water
content to visibility. Visibility at sea ranges from 0 to 13
km (7 n mi - the maximum range to the horizon from the bridge of
most ships). Fog is reported if the visibility is 1 km
(0.5 n mi) or less. Fog production is damped in regions where it
is known to be climatologically rare and when the liquid water
content is great enough to produce larger droplet sizes with a
consequent rise in visibility.
The fog guidance will be available on AFOS at 12-hour intervals
from 12 through 48 hours from both the 0000 and 1200 UTC cycles.
The graphics based on the 0000 UTC cycle will be transmitted at
approximately 1000 UTC; those based on the 1200 UTC cycle will
be available around 2100 UTC. The AFOS identifiers are:
NMCGPH02W 12 HR REGIONAL COASTAL FOG FORECAST
NMCGPH04W 24 HR REGIONAL COASTAL FOG FORECAST
NMCGPH06W 36 HR REGIONAL COASTAL FOG FORECAST
NMCGPH08W 48 HR REGIONAL COASTAL FOG FORECAST
These graphics will show visibilities of 0.5 n mi (fog) and
3.0 n mi. They include the boundaries of the model and a barrier
that distinguishes where fog frequently occurs from areas where
fog rarely occurs (east of the barrier).
In addition to the four AFOS graphics, the fog model output will
eventually be available in GRIB files to Alaska over a dedicated
line and to the Numerical Products Service and the Direct Connect
Service of the Family of Services. The WMO headers for these
files WILL BE:
FXUS42 KWBC 12 HR Regional Coastal Fog GRIB file
FXUS44 KWBC 24 HR Regional Coastal Fog GRIB file
FXUS46 KWBC 36 HR Regional Coastal Fog GRIB file
FXUS48 KWBC 48 HR Regional Coastal Fog GRIB file
A separate National Technical Information Message (NTIM) will
be issued to notify you of the implementation date for the GRIB
files.
The fog model is designed to predict advection fogs and,
therefore, will give the best results during the months of April
through September when advection fogs are most prevalent. The
model is run year round, and adjustments to the post-processor
have been made to account for the over-production of liquid water
during the months of October through March.
A Technical Procedures Bulletin (TPB) describing the fog model
(TPB 398) has been drafted, and should be published in the next
several weeks. If you are on the TPB mailing list, this TPB will
be mailed to you automatically as soon as it is published. If
you are not on the TPB mailing list and would like to receive a
copy of this TPB (or would like to be added to the mailing list),
call (301)-713-0462, or write to:
NOAA/National Weather Service
Office of Meteorology
Services Development Branch, W/OM23
1325 East West Highway, #13466
Silver Spring, MD 20910
If you need more information on the fog model, call Larry
Burroughs of the Marine Prediction Branch at (301)-763-8133.
END
Posted: Thu, Feb 25, 1993 3:12 PM EST Msg: CGJD-5571-8061
k.mielke(rec),
g.hufford(rec), e.young.nws(rec), g.trapp(rec)
CC: l.miller.ucar(rec)
Subj: 2 more NTIMs
I sent 2 more Nat'l Technical Info. Messages today...AFOS PIL WSHPNSNMC/
WMO Header NOUS41 KWBC. The first one discusses changes to statistical storm
surge and beach erosion guidance for the East Coast, effective March 3rd.
The second one discusses future changes to max/min temperature reporting from
ASOS sites AT SOME POINT THIS SUMMER (no exact date has been set).
A follow-up NTIM will be sent once the date has been established.
---------------------------------------------------------------------------
WSHPNSNMC
NOUS41 KWBC 251855
NATIONAL TECHNICAL INFORMATION MESSAGE 93-05
NATIONAL WEATHER SERVICE HEADQUARTERS
200 PM EST THU FEB 25 1993
TO: ALL NWS OFFICES, DOMESTIC DATA SERVICE SUBSCRIBERS,
CARSWELL AFB, CANADIAN AES
FROM: MARY M. GLACKIN
CHIEF, SERVICES DEVELOPMENT BRANCH
SUBJECT: STATISTICAL STORM SURGE AND BEACH EROSION GUIDANCE TO
BE CHANGED FROM LFM-BASED TO NGM-BASED
(THE FOLLOWING INFORMATION WAS PROVIDED BY DR. WILSON SHAFFER OF
THE TECHNIQUES DEVELOPMENT LABORATORY.)
Effective with the 1200 UTC cycle on Wednesday, March 3, 1993,
the statistical storm surge and beach erosion guidance (AFOS PIL
cccMRPECS; WMO header FZUS3 KWBC) for the East Coast will be run
from the Nested Grid Model (NGM). Before this change, this
coastal guidance was generated by using sea level pressures from
the LFM. (Forecast winds never entered the equations.) Since
the equations used for this guidance were based on a "perfect
prog" statistical technique, any improvement in the model
pressure field should result in an improvement to the surge and
erosion forecasts. No rederivation of the "perfect prog"
equations was done. Users are referred to Technical Procedures
Bulletin Nos. 226 and 280 for a description of these products; a
new Technical Procedures Bulletin is being written to cover the
changes in this guidance.
The MRPECS product is transmitted as the FZUS3 KWBC bulletin and
is also available on the NWS's Family of Services Domestic Data
Service circuit, the U.S. Air Force's Automated Weather Network,
and to the Canadian Weather service (AES).
As a result of the change in models, the transmission times of
the storm surge and beach erosion guidance will change. The
product will be available at approximately 0400 and 1600 UTC.
Also, the surface winds and pressures that were appended to the
message will no longer be transmitted. (This change was
coordinated with NWS's Eastern Region Headquarters.) Some
testing of this change has been conducted. WSO Atlantic City was
sent the NGM version of the MRPECS during several recent
extratropical storm surge events. The WSO was very pleased with
the new product.
If you have any questions concerning the MRPECS, please call Will
Shaffer at 301-713-1613 or Paul Dallavalle at 301-763-8151.
END
-----------------------------------------------------------------------
***********************************************************************
WSHPNSNMC
NOUS41 KWBC 251855
NATIONAL TECHNICAL INFORMATION MESSAGE 93-06
NATIONAL WEATHER SERVICE HEADQUARTERS
200 PM EST THU FEB 25 1993
TO: ALL NWS OFFICES, DOMESTIC DATA SERVICE SUBSCRIBERS,
INTERNATIONAL DATA SERVICE SUBSCRIBERS, FAA/WEATHER
MESSAGE SWITCHING CENTER, CANADIAN AES
FROM: MARY M. GLACKIN
CHIEF, SERVICES DEVELOPMENT BRANCH
SUBJECT: ASOS MAXIMUM AND MINIMUM TEMPERATURE CHANGES
(THE FOLLOWING INFORMATION WAS PROVIDED BY DAVE MANNARANO OF THE
ASOS TRANSITION AND IMPLEMENTATION BRANCH OF THE OFFICE OF
SYSTEMS DEVELOPMENT.)
Starting sometime in the Summer of 1993, the meaning of the
maximum/minimum temperature remarks in the ASOS SAO will change
from the current Federal Meteorological Handbook Number 2 -
Surface Synoptic Codes (FMH-2) definition to the draft FMH-1,
Surface Aviation Observations definition. Specifically:
Maximum and Minimum Temperatures Reported at Synoptic Hours
CURRENT CODE FUTURE CODE
TIME (UTC) 1snTxTxTx 2snTnTnTn 1snTxTxTx 2snTnTnTn
0000 12-Hour Max, 18-Hour Min 6-Hour Max, 6-Hour Min
0600 24-Hour Max, 24-Hour Min 6-Hour Max, 6-Hour Min
1200 *PCD Max, 12-Hour Min 6-Hour Max, 6-Hour Min
1800 12-Hour Max, 24-Hour Min 6-Hour Max, 6-Hour Min
* PCD = Previous Calendar Day
Furthermore, in the future the current calendar day's maximum
temperature and minimum temperature will be reported with a
4snTxTxTxsnTnTnTn group in the ASOS hourly SAO at Midnight, Local
Standard Time.
See below for details of the future reporting codes. This is a
preliminary notice. A FOLLOW-UP NOTICE WILL BE ISSUED WHEN A
FIRM IMPLEMENTATION SCHEDULE FOR THIS CHANGE HAS BEEN
ESTABLISHED. In the meantime, please ensure that the attached
notice is given the widest possible dissemination to those who
need to know.
Starting in Summer, 1993, the Maximum Temperature and Minimum
Temperature remarks in the Surface Aviation Observation (SAO)
issued by the Automated Surface Observing System (ASOS) will
change to the following meaning:
1snTxTxTx MAXIMUM TEMPERATURE in degrees Fahrenheit
(F) for the PAST 6 HOURS. This remark is
reported in the 00, 06, 12, & 18 UTC hourly
observations. 1 is the group identifier.
sn is the sign indicator for the max temp.
It is 1 when the max temp is below zero and
0 when the max temp is zero or above.
TxTxTx is max temp in three digits.
EXAMPLE:
10039 = Maximum Temperature is 39 F
11008 = Maximum Temperature is -08 F
2snTnTnTn MINIMUM TEMPERATURE in degrees F for the
PAST 6 HOURS. This remark is reported in
the 00, 06, 12, & 18 UTC hourly
observations. 2 is the group identifier.
sn is the sign indicator for the min temp.
It is 1 when the min temp is below zero and
0 when the min temp is zero or above.
TnTnTn is min temp in three digits.
EXAMPLE:
20029 = Minimum Temperature is 29 F
21015 = Minimum Temperature is -15 F
4s4snTxTxTxsnTnTnTn 24-HOUR MAXIMUM/MINIMUM TEMPERATURE in
whole degrees F. This remark is reported in
the Midnight Local Standard Time hourly
SAO. The maximum and minimum temps reported
in this remark are for the CALENDAR DAY.
4 is the group identifier. sn is the sign
indicator for the following max or min
temp. It is 1 when the following temp is
below zero, and 0 when it is zero or above.
TxTxTx is the CALENDAR DAY max temp; TnTnTn
is the CALENDAR DAY min temp.
EXAMPLE:
400101015 = Max temp is 10 F, and
Min temperature is -15 F.
Please make appropriate adjustments to your systems to handle
these changes.
Once again, a follow-up National Technical Information Message
will be issued once an exact effective date for this change has
been established.
END
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