U.S. DEPARTMENT OF COMMERCE - - ---------- -- -------- NATIONAL OCEANIC AND ATMOSPHERIC -------- ------- --- ----------- ADMINISTRATION -------------- NATIONAL WEATHER SERVICE -------- ------- ------- NATIONAL METEOROLOGICAL CENTER -------- -------------- ------ OFFlCE NOTE 124 ------ ---- --- NMC Format for Surface Reports --- ------ --- ------- ------- Automation Division Staff ---------- -------- ----- JUNE 1976 ---- ---- REVISED APRIL 1982 ------- ----- ---- This is an unreviewed manuscript, primarily intended for Informal exchange of information among NMC staff members . - 2 - This office note describes the format for surface reports in the NMC observa- tional files. The basic format adheres to that described in Office Note #124 (June 1976). The changes made necessary by the January 1, 1982 synoptic code change are explained in detail. Information contained in the NMC observational surface synoptic reports con- sists of combinations from the IBM EBCDIC character set. A negative value is indicated by a minus (-) sign located in the leftmost position. A positive value is unsigned. A report is composed of two main parts: (l) the report identification group of fixed length (50 characters), and (2) the bookkeeping and the observa- tional data of variable length. Each report consists of 70 characters The information contained in the report identification group is given in APPENDIX S.l. The last parameter in this group contains the total number of ten-character words in the report and thus provides the linkage from one report to the next so that several reports may be contained in a block. The report identification group is followed by the category/counter and observa- tional data groups as needed. The format of the category/counter groups is described in APPENDIX S.1. Observational data is formatted according to the categories described in APPENDIX S.2. Where no data of a given category exist, the category/ counter group as well as the data will be absent from the report. The final group in a report contains the ten characters "END REPORT". The number of characters in each category of data is evenly divisi- ble by 10 and the character "X" is used as fill if necessary. Because of this and the length of the groups, the number of characters in a report ( includ- ing the "END REPORT" ) is also evenly divisible by 10. Reports are formatted such that the "END REPORT" signal is found in the same block as the beginning of that report. - 3 - Following are the modifications made necessary by the introduction of FM 12- VII and FM 13-VII January 1, 1982: (1) The code figures for iR, iW, and iX are placed into characters 25, 26 and 27 respectively of the report identification group. (2) The second character of past weather W2 , is located in the 36th char- acter of category 51. (This location was previously assigned to the quality mark of dew point depression.) (3) Category 08 code figures give section and group number information. For example, code figure 136 means the data are from a 6-group in section 3 of FM 12-VII or FM 13-VII. (4) Section 5 of WMO code FM 12-VII is stored in category 09. These data are indicated by a "5" in the first character of the first group only. The hourly (SA) data remarks section is stored in category 09 indicated by a "1" in the first character of each group. (5) Pressure level indicator "1" has changed meaning from 1000 gpm to 1000 mb. (Several of the old indicators are no longer used). (6) tR, the length of time covered by the 6RRRtR group is located in the 12th character of category 52. (This location was previously assigned to Rt, time precipitation began.) (7) Period of swell waves in category 52 has changed from a code figure to seconds. (8) The unit of wave height in category 52 has changed from half-yard to half-meter. (9) The units of 24-hour pressure change have been changed from a code fig- ure to tenths of millibars. If the pressure change is less than zero the value stored is the absolute value (in tenths) plus 500. (10) Certain reports are actually converted hourlies (stored with block sta- tion identification and report type 511). The 37th character of the report identification group indicates whether the report is a converted hourly or a regular synoptic report (l=hourly, 9=regular synoptic). (11) Hourly reports (stored with call letter identification and report type 512) have experienced no changes due to the January 1, 1982 code change. - 4 - LIST OF APPENDICES APPENDIX S.1 Page No. Report Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Category/Counter Group . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 APPENDIX S.2 Formats for the data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Category 51 - Surface Data . . . . . . . . . . . . . . . . . . . . . . . . . 5 Category 52 - Surface Data . . . . . . . . . . . . . . . . . . . . . . . . . 6 Category 08 - Additional Data . . . . . . . . . . . . . . . . . . . . . . . . 7 Category 09 - Plain Language Data . . . . . . . . . . . . . . . . . . . . . . 7 APPENDIX S.3 Table SM.l - Report Type . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table SM.8 - Additional Data . . . . . . . . . . . . . . . . . . . . . . . . 9 Table SM.9 - Plain Language Data . . . . . . . . . . . . . . . . . . . . . . 10 Table SM.51- Markers for Parameters . . . . . . . . . . . . . . . . . . . . . 10 Sample Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 - 5 - APPENDIX S.1 REPORT IDENTIFICATION (40 Characters) Character Number(s) Parameter Unit Remarks 1-5 Latitude* Hundredth of a degree Negative in S.H. 6-10 West longitude* Hundredth of a degree Values 00000 11-16 Station Alphanumeric Left aligned, blank identification fill 17-20 Observation time* Hundredth of an hour Values 0000 to 2399 9 21-24 Receipt time* Hundredth of an hour Values 0000 to 2399 25-27 Flags iR, iW, iX --------- ---------- 31-35 Station elevation* Meter Negative if < sea level 36 Synoptic format flag ---------- New=1, old=9 land synoptic only 37 Converted hrly flag ---------- Hrly=1, regular=9 38-40 Total length 10-character word ---------- of report * Whenever value is "missing" or not applicable, all characters for the parameter will contain "9". CATEGORY/COUNTER GROUP (10 Characters) Character Number(s) Parameter 41-42 Category code figure from APPENDIX S.2. 43-45 Relative position in report of the next category/counter group.* 46-47 Number of times data format for category is repeated (i.e., the number of entries) 48-50 Total number of characters in current category (fill characters not counted) * The number of 10-character words in the report which precedes the next category/counter group plus 1. - 6 - APPENDIX S.2 Category 51 - Surface Data (60 characters each entry) No. of characters Parameter Unit 5 Sea-level pressure* Tenth of millibar 5 Station pressure Tenth of millibar 3 Wind direction Degree 3 Wind speed Knot 4 Air temperature Tenth of degree C 3 Dewpoint depression " " " " 4 Maximum temperature " " " " 4 Minimum temperature " " " " 1 Quality mark (sea-level pressure) Character from Table SM.51 1 Quality mark( station pressure) " " " " 1 Quality mark (wind) " " " " 1 Quality mark (air temperature) " " " " 1 Past weather(W2) WMO code table 4561 3 Horizontal visibility WMO code table 4300 3 Present weather WMO code table 4677 2 Past weather (W1) WMO code table 4561 2 Fraction of the celestial dome WMO code table 2700 covered by cloud (N) 2 Fraction of the celestial dome WMO code table 2700 covered by all the CL (or CM) clouds present (Nh) 2 Clouds of genera Sc, St, Cu, Cb WMO code table 0513 (CL) 2 Height above ground of the base WMO code table 1600 of the cloud (h) 2 Clouds of genera Ac, As, Ns (CM) WMO code table 0515 2 Clouds of genera Ci, Cc, Cs (CH) WMO code table 0509 1 Characteristic of pressure WMO code table 0200 tendency during the 3 hours preceding the time of observation (a)** 3 Amount (magnitude) of the Tenth of millibar pressure tendency** *See note on following page. **When the characteristic of pressure tendency is 9 and the amount of the pressure tendency is not 999, the tendency is a 24-hour pressure change in tenths of millibars unless less than zero. In this case the stored value is the absolute value (in tenths) of pressure tendency plus 500. - 7 - *Reference Category 51, sea-level pressure (PPPPP), the following infor- mation describes the method for accommodating the possible values encoded in the 4PPPP group of FM 12-VII. Characters Level Unit PPPPP Sea level Tenth of millibar 21PPP 1000mb Geopotential meter 25PPP 500mb Geopotential meter 27PPP 700mb Geopotential meter 28PPP 850mb Geopotential meter 29PPP Unknown (as reported) Category 52 - Surface Data (40 characters each) No. of Characters Parameter Unit 4 Amount of precipitation past 6 hours* Hundredth of an inch 3 Total depth of snow on ground** Inch 4 Total precipitation past 24 hours* Hundredth of an inch 1 Duration of precipitation observation Number of 6-hour periods 2 Period of waves*** Second 2 Height of waves Half meter 2 Direction from which swell waves WMO code table 0877 are moving 2 Period of swell waves Second 2 Height of swell waves Half meter 4 Sea surface temperature Tenth of degree C 2 Special phenomena, general **** 2 Special phenomena, detailed **** 1 Ship's course WMO code table 0700 2 Ship's average speed WMO code table 4451 7 Water equivalent of snow and/or ice Hundredth of an inch * Trace is output as 9998. ** Trace is output as 998. *** No estimate due to confused sea--output as 98. **** Special phenomena, general, is missing (99) only if special phenomena, detailed, is missing (99). - 8 - Category 08 - Additional Data (10 characters each entry) No. Of characters Parameter Unit 5 Data given by specification in Table SM.8a* Variable 3 Form of data Code figure from Table SM.8a 1 Indicator for specification Character from Table SM.8b 1 Indicator for form Character from Table SM.8c Note--Entries will be ordered as encountered in report. *Value set "missing" (99999) indicates transmitted as missing. Category 09 - Plain Language Data (12 characters each entry) No. of characters Parameters Unit 1 Indicator of content of the Character from plain language Table SM.9 11 Plain language data Alphanumeric text - 9 - APPENDIX S.3 TABLE SM.1 - Report types Code Figure Type of report Land station 511 By international index number 512 By call letters 513 By latitude-longitude Ocean station 521 Fixed (OWS) 522 Moving ship with name 523 Moving ship without name Marine reporting station (MARS) 531 Fixed (Stationary) 532 Moving Quality control data 551 By latitude-longitude Buoy 561 Moored 562 Drifting TABLE SM.8a - Code figures and specifications for Category 08 Code Figure Specification 014 Station international index number 020 Altimeter setting in 10th of mb 080 Sunshine data (see...pg C17-2 FMH#2) - 10 - TABLE SM.8b - Indicator for specification Character Meaning blank Not specified TABLE SM.8c - Indicator for form Character Meaning blank Not specified 4 digits 4 digit transmitted output 0* XXXX XXXX 1* XXX/ XXX9 2* XX/X XX9X 3* XX// XX99 4* X/XX X9XX 5* X/X/ X9X9 6* X//X X99X 7* X/// X999 8* /XXX 9XXX 9* /XX/ 9XX9 A* /X/X 9X9X B* /X// 9X99 C* //XX 99XX D* //X/ 99X9 E* ///X 999X F* //// 9999 *Applies only to code figures 110 through 139. - 11 - TABLE SM.9 - Content of plain language data Character Parameter Meaning Blank Any Not specified H Any Monitor requests retention P Any Monitor requests non use A Wind Ship and buoy reports-wind measurements by anemometer A Sea-level Good agreement between sea-level and pressure station pressure B Sea-level Disagreement between sea-level and pressure station pressure C Sea-level Missing station pressure for which pressure expected D Sea-level Fair agreement between sea-level and pressure station pressure D Station Unreliable sea-level pressure from a pressure ship report - 12 - Sample Reports to Illustrate Formats Typical land station other than blocks 70-74 070930086701001 12001223191511000091901551012010600993699999 350023-08803399999999 20200360308080803101020050801502020 69901116 091137139 0 END REPORT Typical land stations from blocks 70-74 035400976072353 12001223392511003971901551012010601013209672 180010005007201390050A 0749999900999909999930050901602024 51047 058047************XXXXXXEND REPORT 037621223872494 12001225392511000051901651012010601023010224 290007013907802830133A 0819999908020009050730030901501012 5HIXDA******XXXXXXXXEND REPORT Typical hourly ( SA) report 0422007253CEF 12001155999512000759902351012010601009899999 300010022701199999999 0400109903030602101010075201701040 0003999999999999999999999999999999999999080190101074491014 0 9023020241 20003 WET lRWY XXXXXXEND REPORT Typical moving ship (without name) 0264022200SHIP 12001242444523000009901751012010601018099999 060011018504099999999 A 0989999908080506101020205201701040 9999999999990101999999019099990000099999END REPORT