GHCN Daily Notifications

GHCN Daily Data Change Notification 42

matthew.menne@noaa.gov — Thu, 20 Sep 2012 00:00:00 EDT

Effective September 24, 2012
A new version of GHCN-Daily (v3.00) will be deployed that includes two new station networks for the U.S.:

The SNOwpack TELemtry (SNOTEL) Network (668 stations)
The Remote Automatic Weather Station (RAWS) Network (1453 "permanent" stations)

Data for both networks are obtained from the U.S. Western Regional Climate Center. GHCN-Daily IDs for SNOTEL stations are based on the Natural Resources Conservation Service (NRCS) alfanumeric identifiers and are denoted by the network code "S". The data source flag for SNOTEL data values is 'T'. Elements for SNOTEL stations include TMAX,TMIN,TOBS,PRCP,WESD. RAWS station identifiers are denoted by the network code "R". The data source flag for RAWS data values is 'U'. Elements for RAWS stations are limited to TMAX and TMIN. Since these temperatures represent the highest and lowest hourly values for the day, they are accompanied by the measurement flag 'H'.

GHCN Daily Data Change Notification 41

matthew.menne@noaa.gov — Wed, 20 Jun 2012 00:00:00 EDT

Effective June 25, 2012
A new version of GHCN-Daily (v2.93) is expected to be deployed on Monday, June 25, 2012 that includes updates for many Russian stations as well as for a few stations in some surrounding countries. At the same time, 116 stations that are new to GHCN-Daily will be added for the same region. A new data source code (lower case "r") will be introduced to indicate that these updates and additions are provided by the All-Russian Research Institute of Hydrometeorological Information-World Data Center (ARRIHI-WDC). This new data source will lead to an increase of between 10 and 20 million daily values in the dataset and to a comparable number of replacement values since the ARRIHI-WDC source will supersede values from other sources for existing stations that are being updated by the new ARRIHI-WDC data. In most of these cases, only the source flag will change. In addition, the network identification code for most Russian stations will change from "0" (unspecified) to "M" (based on the World Meteorological Organization identification number). In general, only the third character of the GHCN-Daily ID will change (e.g., RS000027612 becomes RSM00027612).

GHCN Daily Data Change Notification 40

matthew.menne@noaa.gov — Wed, 1 Feb 2012 00:00:00 EDT

Effective January 30, 2012
GHCN-Daily version 2.91 will be available with the following changes:

Data source flag (SFLAG) "Z" will be added to denote official data additions and replacements associated with the Datzilla data error tracking system. Version 2.91 includes Datzilla values for ASOS stations including temperature, precipitation and snowfall, and snowdepths edits for 2011 and approximately 200000 snowfall and snowdepth values submitted by Weather Forecast Offices for years prior to 2011.
The number of station will increase by 268 with the addition of newly available CoCoRaHS stations. The total number of stations is now 80615.

GHCN Daily Data Change Notification 39

matthew.menne@noaa.gov — Wed, 16 Nov 2011 00:00:00 EDT

Effective November 21, 2011
On Monday, November 21, 2011 the following changes for GHCN-Daily are planned:

About 1270 new stations will be added from the European Climate Assessment (ECA) data set At the same time, approximately 450 stations already in GHCN Daily will receive updates and/or edits from the ECA source (data source flag [SFLAG] = "E"). The additions and updates will increase the number of values in GHCN-Daily by approximately 50 million (50000000), and the source flag for a number of existing values will change to "E" to reflect the addition of the new ECA source.
ECA data are described in Klein Tank, A.M.G. and Coauthors (2002): Daily dataset of 20th-century surface air temperature and precipitation series for the European Climate Assessment. Int. J. of Climatol., 22, 1441-1453. Data and metadata available at http://eca.knmi.nl).
The station identifier "SI000000192" (LJUBLJANA BEZIGRAD) will change to "SIM00014015".

GHCN Daily Data Change Notification 38

matthew.menne@noaa.gov — Wed, 16 Nov 2011 00:00:00 EDT

The GHCN-Daily website has been updated to reflect recent additions and changes to the data set. In particular, additional information is now provided to U.S. data users regarding the distinction between real-time data updates and time-delayed, archive-quality data sources.

GHCN Daily Data Change Notification 37

matthew.menne@noaa.gov — Wed, 14 Sep 2011 14:16:00 EDT

Effective September 15, 2011

NCDC DSI 3207 data (WxCoder3) are added for July 2011 (SFLAG="7")
U.S. Cooperative Summary of the Day data digitized from paper observer forms between September 7 and September 14, 2011 are added (SFLAG="K")

GHCN Daily Data Change Notification 36

matthew.menne@noaa.gov — 12 Sep 2011

Effective September 12, 2011

DSI 3200 is given priority over DSI 3206
The measurement flag "P" is added for values identified as "missing presumed zero" in DSI 3200 and 3206. This flag was set in DSI 3200 and 3206 when no value was indicated by the observer. Affected are more than 100 million PRCP, SNOW, or SNWD values. Particularly for data before 1982, it appears that the absence of the "missing presumed zero flag" does not necessary imply that the value was originally recorded as zero.

GHCN Daily Data Change Notification 35

matthew.menne@noaa.gov — 13 Jun 2011

Effective June 13, 2011

Data source "K" (U.S. Cooperative Observer Summary of the Day) data digitized from paper forms will be added. Weather types, soil temperatures, water equivalent of snow depth from source "K" are forthcoming. Beginning in 2011, U.S. Cooperative Observer data is comprised of sources "7" and "K" and "H". The last year for DSI-3200 is 2010, with sources "7" and "K" being a direct continuation of DSI 3200. Source "H" provides real time updates.
Elements PRCP, SNOW and SNWD from source "M" will be removed. Daily precipitation totals from this source were too small.

GHCN Daily Data Change Notification 34

matthew.menne@noaa.gov — 23 May 2011

Effective May 23, 2011
Data source "2" (preliminary keyed data for U.S. Cooperative Observer stations) has been removed. Note that data source 2 at some stations was attributed to the wrong calendar month.

GHCN Daily Data Change Notification 33

matthew.menne@noaa.gov — 16 May 2011

Effective May 16, 2011
GHCN-Daily version 2.70 will be replace by version 2.80. This includes the following changes:

The records for approximately 800 U.S. stations are now indexed using network code "W" instead of network code "C". For example, data for ASHEVILLE AP are stored under GHCN-Daily USW00003812 instread of USC00310300.
Reidentified the data sources for all U.S. stations to reflect changes in the indexing of stations in the source datasets
Data from source "1" has been replace by source "7" (DSI-3207-WxCoder3).
The file "ghcnd-us-states.txt" has been replaced with "ghcnd-states.txt" and now also includes codes for Canadian provinces

GHCN Daily Data Change Notification 32

matthew.menne@noaa.gov — 14 Feb 2011

Effective February 14, 2011

31 new elements will be added from DSI 3210. See the readme.txt file for element definitions.
The element for water equivalent of snow on the ground has changed from "WTEQ" to "WESD" to be consistent with the element "WESF".
A fix will be implemented to take into account an undocumented way in which multiday totals are reported in DSI 3200. The fix corrects the number of days in multiday sums after the year 2004 at U.S. stations
The number of stations will increase by 12 from 76671 to 76683 with the addition of new U.S. Cooperative Observer Stations.

GHCN Daily Data Change Notification 31

matthew.menne@noaa.gov — 21 Jan 2011

Effective January 24, 2011
The number of GHCN-Daily stations will increase by 325 to a total 76671 with the addition of new U.S. Cooperative Observer and CoCoRaHS stations.

GHCN Daily Data Change Notification 30

matthew.menne@noaa.gov — 17 Dec 2010

Effective December 20, 2010
The number of GHCN Daily stations will increase by 36 to a total 76346 with the addition of new U.S. Cooperative Observer stations. In addition, the following station ids were changed to reflect the correct FIPS country codes:

USC00668814 changed to RQC00668814
USC00670820 changed to VQC00670820
USC00671316 changed to VQC00671316
USC00671348 changed to VQC00671348
USC00671790 changed to VQC00671790
USC00671980 changed to VQC00671980
USC00672551 changed to VQC00672551
USC00674820 changed to VQC00674820
USC00679222 changed to VQC00679222

GHCN Daily Data Change Notification 29

matthew.menne@noaa.gov — 10 Dec 2010

Effective December 13, 2010
GHCN Daily version 2.60 will be released with the following changes:

The addition of elements 'DAEV', 'DASF' and 'DAWM' (Number of days in multiday evaporation, snowfall, and wind movement).
The element 'DAPR', previously only available for Australia, will also be provided for U.S. stations. These elements will be flagged with QFLAG='L' when the length of a multiday period is less than 2 days or greater than 31 days, or when a single day observation is present during the interval covered by a corresponding multiday element.

GHCN Daily Data Change Notification 28

matthew.menne@noaa.gov — 15 Oct 2010

Effective October 25, 2010
The number of stations in GHCN Daily will increase by 903 to a total of 76142 with the addition of newly available CoCoRaHS stations and updates for Ukraine (SFLAG='u'), Uzbekistan (SFLAG='z'), and Belarus (SFLAG='b').

GHCN Daily Data Change Notification 27

matthew.menne@noaa.gov — 17 Sep 2010

Effective September 17, 2010

Data from approximately 17000 Australian stations will be added on 20 September 2010. These data, supplied by the Australian Bureau of Meteorology, replace any previous data for Australian stations and will be updated monthly. The new total number of stations in GHCN Daily is 75239.
A set of new elements have been created to represent values pertaining to multiday observational periods (e.g., MDPR = precipitation accumulated over more than one day). Multiday values previously identified with an "A" QFLAG are now identified using the new multiday element codes instead. See the element list in the readme.txt file for definitions of the new element codes.

GHCN Daily Data Change Notification 26

matthew.menne@noaa.gov — 13 Aug 2010

Effective August 16, 2010

The locations, names, and WMO numbers of active U.S. stations in the GHCN-Daily station list (ghcnd-stations.txt) have been updated to agree with the latest information available in NCDC's Master Station History Record.
Data for 37 newly opened U.S. Cooperative Network stations will be part of GHCN-Daily, bringing the total number of stations to 58221.

GHCN Daily Data Change Notification 25

matthew.menne@noaa.gov — 9 Jul 2010

Effective July 12, 2010
Data from the Community Collaborative Rain, Hail, and Snow (CoCoRaHS) Network will be added to GHCN Daily. This additional source will increase the number of stations from 44010 to 58184. This new source also provides a element new to GHCN Daily: Water Equivalent of SnowFall (WEFS). The source flag (SFLAG) for CoCoRaHS is "N".

GHCN Daily Data Change Notification 24

matthew.menne@noaa.gov — 16 Jun 2010

Effective June 21, 2010
As of June 21, 2010 daily precipiation from source "G" have been removed until uncertainty about the units is resolved. Note that many of the values were an order of magnitude too small. Some of the removed totals from the 'G' source are replaced by sources 'I' and 'S'.

GHCN Daily Data Change Notification 23

matthew.menne@noaa.gov — 4 Jun 2010

Effective June 7, 2010
The number of stations in GHCN Daily has increased by 89 with the addition of newly assigned U.S. Cooperative Observer Network stations. The total number of stations is now 44 010. Data files for these new stations will be available June 07, 2010.
The longitudes for the following stations were corrected by adding a negative sign:

USC00023096
USC00053010
USC00189674
USC00300958
USC00413270

The id for RQC00670260 was changed to VQC00670260.

GHCN Daily Data Change Notification 22

matthew.menne@noaa.gov — 13 Apr 2010

Effective April 13, 2010
The temperature at observation time (element code TOBS) is now included in the real-time updates received from the High Plains Regional Climate Center (source code H) beginning in early April 2010. As a result, TOBS is now being updated in real time at many GHCN-Daily stations where it was not updated previously.

GHCN Daily Data Change Notification 21

matthew.menne@noaa.gov — 6 Apr 2010

Effective April 6, 2010
The following two issues affecting precipitation totals in GHCN-Daily have been brought to our attention:

At stations in the United Kingdom and France, precipitation totals with a data source flag of "G" appear to be in units of millimeters rather than tenths of millimeters. We are investigating this problem and will update this status file when the problem has been rectified.
The mingling of daily and multi-day precipitation totals from multiple sources seems to have created some instances in which the same precipitation event appears on consecutive days in GHCN-Daily. This issue will be addressed sometime in the coming months. In the meantime, users interested in processing multi-day precipitation accumulations identified with a quality-control flag of "A" are advised to set such accumulated totals to missing if they are preceded by a nonmissing value on the preceding day.

GHCN Daily Data Change Notification 20

matthew.menne@noaa.gov — 12 Feb 2010

Effective February 12, 2010
The following changes were made according to research performed by the NCDC metadata team on DSI 3206:

Station data for USC00094203 has now been merged with station USC00094204
Station data for USC00170488 has now been merged with station USC00170480
Station data for USC00245054 has now been merged with station USC00245045

There are now 43921 stations in GHCN Daily.

GHCN Daily Data Change Notification 19

matthew.menne@noaa.gov — 5 Feb 2009

Effective February 5, 2010
Historical data from several African countries will be added on 08 February 2010. A number of newly available U.S.Cooperative Observer stations will also be added at this time bringing the total number of GHCN Daily stations to 43924.

GHCN Daily Data Change Notification 18

matthew.menne@noaa.gov — 18 Dec 2009

Effective December 18, 2009
A file that specifies the current version of GHCN Daily (i.e. time stamp of last processing) is now provided in the ftp directory and all tar.gz files. The name of the version control file is "ghcnd-version.txt".

GHCN Daily Data Change Notification 17

matthew.menne@noaa.gov — 23 Nov 2009

Effective November 23, 2009
Version 2.1 was placed online with the following changes:

The number of stations in ghcn daily increased from 43630 to 43713 with the addition of newly opened U.S. Cooperative Observer stations.
The following elements have been added for U.S. stations: Pan Evaporation, Max and Min Pan Temperature, Max and Min Soil Temperatures at various depths, Water Equivalent of Snow on the Ground, Weather Types, and 24 Wind Movement.

See the "readme.txt" for corresponding element codes and quality flags.

GHCN Daily Data Change Notification 16

matthew.menne@noaa.gov — 5 Jun 2009

Effective June 8, 2009
The number of stations in ghcn daily will increase by 137 to 43630 on June 08, 2009 with the addition of NOAA Climate Reference Network and U.S. Historical Climatology Network-Modernized stations.

GHCN Daily Data Change Notification 15

matthew.menne@noaa.gov — 10 Apr 2009

Effective April 13, 2009
The of number of stations in ghcn-daily will increase by 2 to 43493 on April 13, 2009.

GHCN Daily Data Change Notification 14

matthew.menne@noaa.gov — 3 Apr 2009

Effective April 6, 2009
Begining April 6, the following changes will take place:

QFLAG "F" becomes "N"
QFLAG "T" becomes "X" (for SNWD only)
The number of "K" QFLAGs for TMAX, TMIN, TOBS, and PRCP is reduced due to an increase in the streak check threshold to 20 for all four variables
A new measurement flag (MFLAG="L") is added for temperature to identify months in which temperatues appear to be lagged (out of phase) with the reported observation time.

GHCN Daily Data Change Notification 13

matthew.menne@noaa.gov — 18 Feb 2009

Effective February 18, 2009
Added the "Spatial Regression" check, which flags maximum and minimum temperature values that are spatial outliers. This addition increases the number of temperature values flagged as spatial outliers (QFLAG = "S").

GHCN Daily Data Change Notification 12

matthew.menne@noaa.gov — 17 Dec 2008

Effective December 17, 2008
U.S. Forts data have been added as a data source and will appear in station files on December 22, 2008. The number of stations is now 43491. The GSN designations for stations in Canada have also been updated. There are now 886 GSN stations in the /gsn directory.

GHCN Daily Data Change Notification 11

matthew.menne@noaa.gov — 7 Nov 2008

Effective November 7, 2008
Removed four stations from ghcnd-stations.txt for which no data were available.

GHCN Daily Data Change Notification 10

matthew.menne@noaa.gov — 18 Aug 2008

Effective August 18, 2008
Added the temperature at the time of observation denoted as TOBS as a sixth element The previous temperature internal consistency and three-day consistency checks (QFLAG = "I" or "C") have been replaced with an integrated consistency check among elements TMAX, TMIN, and TOBS (QFLAG = "I"). This new check flags a considerably larger number of temperature values. The element TOBS and the new check will be added to data for 2008 beginning August 18 and to other years on August 25, 2008.

GHCN Daily Data Change Notification 9

matthew.menne@noaa.gov — 24 Jun 2008

Effective June 24, 2008
The processing problem affecting "O" quality flags for Canadian snowfall and snow depth observations has been fixed. "O" flags for these observations can now be treated like all other quality flags.

GHCN Daily Data Change Notification 8

matthew.menne@noaa.gov — 16 Jun 2008

Effective June 16, 2008
Because of an error in processing snowfall and snow depth users should ignore any "O" quality flags for elements "SNOW" and "SNWD" at Canadian stations.

GHCN Daily Data Change Notification 7

matthew.menne@noaa.gov — 7 Jun 2008

Effective June 7, 2008
Added Preliminary (Transmitted and Keyed) Cooperative Summary of the Day Data (Data Source Flags equal 1 and 2, respectively), which increases the number of stations by 128 to 43 490

GHCN Daily Data Change Notification 6

matthew.menne@noaa.gov — 30 May 2008

Effective May 30, 2008
A new GHCN-Daily system has now been deployed. Please note the following:

The first 3 characters of the station identification code have changed from the 3 digit country code to a two-character FIPS country code plus a network code.
The format of the station inventory has changed.
The number of stations has increased to more than 43 000
The elements SNOW (snowfall) and SNWD (snow depth) were added.

See the readme.txt for details

GHCN Daily Data Change Notification 5

matthew.menne@noaa.gov — 19 May 2008

Effective May 19, 2008
Please note that a new version of GHCN-Daily will be deployed the week of 19 May 2008. Data files will not be available for a few days prior to deployment.

GHCN Daily Data Change Notification 4

matthew.menne@noaa.gov — 6 May 2008

Effective May 6, 2008
Due to a processing problem, historical data for the U.S. are currently not available. We expect the problem to be fixed within a few days.

GHCN Daily Data Change Notification 3

matthew.menne@noaa.gov — 1 May 2007

Effective May 1, 2007
Changed the threshold for the temperature GAP check from 11.81 to the intended 10.0 Deg C.

GHCN Daily Data Change Notification 2

matthew.menne@noaa.gov — 28 Apr 2007

Effective April 28, 2007
Fixed data source merging process to include updated official GCOS data (i.e., values with data source flag "G").

GHCN Daily Data Change Notification 1

matthew.menne@noaa.gov — 21 Dec 2006

Effective December 21, 2006
Version 2.0 of GHCN Daily was placed online in this FTP directory.