{"station":{"icao":"KIAD","cliId":"IAD","pil":"CLIIAD","city":{"slug":"washington","name":"워싱턴 D.C.","country":"United States"},"timezone":"America/New_York","feed":"https://api.weather.gov/products/types/CLI/locations/IAD","html":"https://weathermarket.io/nws-cli/KIAD","json":"https://weathermarket.io/api/nws-cli/KIAD"},"stationToday":"2026-11-14","day":{"date":"2026-08-31","status":"issued","note":"Final CLI issued - values.nwsOfficial carries the official daily values (metric here; official.issued.asReported keeps the °F / inch / mph exactly as printed).","settlement":{"tmaxF":86,"tminF":69,"precipIn":0,"precipTrace":true,"tmax":30,"tmin":20.56,"precip":0,"issuedAt":"2026-09-01T06:28:00.000Z","productId":"iem:CDUS41-KLWX-010628:IAD:2026-08-31:final","corrected":false,"reissues":0,"nwsProductUrl":null,"iemArchiveUrl":"https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=CLIIAD&e=202609010628"},"issues":[{"kind":"final","asOfLocal":null,"issuedAt":"2026-09-01T06:28:00.000Z","issuedLocal":"228 AM EDT TUE SEP 01 2026","office":"KLWX","wmoHeader":"CDUS41 KLWX 010628","productId":"iem:CDUS41-KLWX-010628:IAD:2026-08-31:final","source":"iem-afos","corrected":false,"tmaxF":86,"tmaxTimeLocal":"1:04 PM","tminF":69,"tminTimeLocal":"4:41 AM","precipIn":0,"precipTrace":true,"snowIn":0,"snowTrace":false,"nwsProductUrl":null,"iemArchiveUrl":"https://mesonet.agron.iastate.edu/wx/afos/p.php?pil=CLIIAD&e=202609010628","parseProblems":[],"rawTextSha256":"1de69fe10e338a225c11d5193bc5253c2c094d142a0d679e23225e4a19f0a8ce","rawText":"CDUS41 KLWX 010628\nCLIIAD\n\nCLIMATE REPORT \nNATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC \n228 AM EDT TUE SEP 01 2026\n\n...................................\n\n...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR AUGUST 31 2026...\n\nCLIMATE NORMAL PERIOD: 1991 TO 2020\nCLIMATE RECORD PERIOD: 1960 TO 2026\n\n\nWEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST \n VALUE (LST) VALUE VALUE FROM YEAR \n NORMAL \n...................................................................\nTEMPERATURE (F) \n YESTERDAY \n MAXIMUM 86 1:04 PM 98 1991 84 2 79 \n MINIMUM 69 4:41 AM 43 1976 63 6 48 \n AVERAGE 78 74 4 64 \n\nPRECIPITATION (IN) \n YESTERDAY T 3.21 1975 0.11 -0.11 0.00 \n MONTH TO DATE 4.85 3.53 1.32 0.85 \n SINCE JUN 1 14.48 11.98 2.50 10.72 \n SINCE JAN 1 29.40 29.22 0.18 24.64 \n\nSNOWFALL (IN) \n YESTERDAY 0.0 MM MM 0.0 0.0 0.0 \n MONTH TO DATE 0.0 0.0 0.0 0.0 \n SINCE JUN 1 0.0 0.0 0.0 0.0 \n SINCE JUL 1 0.0 0.0 0.0 0.0 \n SNOW DEPTH 0 \n\nDEGREE DAYS \n HEATING \n YESTERDAY 0 0 0 1 \n MONTH TO DATE 0 0 0 2 \n SINCE JUN 1 1 13 -12 17 \n SINCE JUL 1 0 0 0 2 \n\n COOLING \n YESTERDAY 13 9 4 0 \n MONTH TO DATE 394 334 60 232 \n SINCE JUN 1 1107 950 157 1030 \n SINCE JAN 1 1280 1056 224 1148 \n...................................................................\n\n\nWIND (MPH) \n HIGHEST WIND SPEED 10 HIGHEST WIND DIRECTION N (10) \n HIGHEST GUST SPEED 13 HIGHEST GUST DIRECTION N (360) \n AVERAGE WIND SPEED 2.7 \n\n\nSKY COVER \n AVERAGE SKY COVER 0.8 \n\n\nWEATHER CONDITIONS \nTHE FOLLOWING WEATHER WAS RECORDED YESTERDAY. \n LIGHT RAIN \n\n\nRELATIVE HUMIDITY (PERCENT)\n HIGHEST 100 1:00 AM \n LOWEST 61 5:00 PM \n AVERAGE 81 \n\n..........................................................\n\n\nTHE WASHINGTON DULLES DC CLIMATE NORMALS FOR TODAY\n NORMAL RECORD YEAR \n MAXIMUM TEMPERATURE (F) 84 98 1962 \n 1980 \n MINIMUM TEMPERATURE (F) 63 49 1970 \n 1976 \n\n\nSUNRISE AND SUNSET \nSEPTEMBER 1 2026.....SUNRISE 6:39 AM EDT SUNSET 7:40 PM EDT \nSEPTEMBER 2 2026.....SUNRISE 6:40 AM EDT SUNSET 7:39 PM EDT \n\n\n- INDICATES NEGATIVE NUMBERS.\nR INDICATES RECORD WAS SET OR TIED.\nMM INDICATES DATA IS MISSING.\nT INDICATES TRACE AMOUNT.\n\n\n\n\n$$"}],"html":"https://weathermarket.io/nws-cli/KIAD/2026-08-31","json":"https://weathermarket.io/api/nws-cli/KIAD/2026-08-31"},"about":{"product":"NWS Climatological Report (CLI): the daily climate summary issued by the local NWS forecast office from the station's 1-minute ASOS record, normally 1-3 hours after local midnight (final, 'YESTERDAY') and once during the day (interim, 'TODAY AS OF'). Corrections are re-issued under the same PIL with CORRECTED in the text.","settlementRule":"The settlement value for a date is the latest final CLI issued for that date; a corrected re-issue supersedes earlier issues. Interim same-day products never settle. This is the same rule that fills values.nwsOfficial in /api/station/{icao}/daily.","archive":"Every issue is stored verbatim as received - nothing is edited or re-derived. Products are held from 2026-09-01 (backfilled from the IEM AFOS archive) and ingested live from api.weather.gov since 2026-11-10, polled every 30 minutes. A date with no final CLI 14 hours after local midnight is reported as not_issued rather than filled in.","verify":["Each issue carries the NWS product id (api.weather.gov keeps products for a limited time) and a link to the IEM AFOS permanent archive of the same product.","rawTextSha256 is the SHA-256 of the stored product text; compare it with the text at either link to confirm nothing was altered.","Permalink pattern for market rules: https://weathermarket.io/nws-cli/KIAD/YYYY-MM-DD (HTML) and https://weathermarket.io/api/nws-cli/KIAD/YYYY-MM-DD (JSON)."],"citation":"Settlement source: the final NWS Climatological Report (CLI) for station KIAD for the contract date, as archived verbatim at https://weathermarket.io/nws-cli/KIAD/YYYY-MM-DD with links to the NWS product and the IEM archive. A CORRECTED re-issue published before the settlement time supersedes earlier issues."}}