NWS CLI archive · settlement source
CLIIAD · 워싱턴 D.C. · America/New_York · ← 2026-09-10 · 2026-09-12 → · All dates for KIAD · JSON · METAR-derived record
Final issued 2026-09-12 02:26:00 EDT · Product id iem:CDUS41-KLWX-120626:IAD:2026-09-11:final · IEM archive
Product id iem:CDUS41-KLWX-120626:IAD:2026-09-11:final · iem-afos · IEM archive
SHA-256 211c4b9ab7603d837faf10971977a36312a527498934707819a8c5d91b8acf58
Product text
CDUS41 KLWX 120626
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
226 AM EDT SAT SEP 12 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 11 2026...
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1960 TO 2026
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...................................................................
TEMPERATURE (F)
YESTERDAY
MAXIMUM 79 5:24 PM 99 1983 81 -2 84
MINIMUM 66 11:57 PM 40 1976 60 6 58
AVERAGE 73 70 3 71
PRECIPITATION (IN)
YESTERDAY 0.56 1.45 2023 0.13 0.43 T
MONTH TO DATE 1.39 1.35 0.04 0.18
SINCE SEP 1 1.39 1.35 0.04 0.18
SINCE JAN 1 30.79 30.57 0.22 24.82
SNOWFALL (IN)
YESTERDAY 0.0 MM MM 0.0 0.0 0.0
MONTH TO DATE 0.0 0.0 0.0 0.0
SINCE SEP 1 0.0 0.0 0.0 0.0
SINCE JUL 1 0.0 0.0 0.0 0.0
SNOW DEPTH 0
DEGREE DAYS
HEATING
YESTERDAY 0 1 -1 0
MONTH TO DATE 0 2 -2 6
SINCE SEP 1 0 2 -2 6
SINCE JUL 1 0 3 -3 8
COOLING
YESTERDAY 8 6 2 6
MONTH TO DATE 134 80 54 45
SINCE SEP 1 134 80 54 45
SINCE JAN 1 1414 1136 278 1193
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 12 HIGHEST WIND DIRECTION N (360)
HIGHEST GUST SPEED 16 HIGHEST GUST DIRECTION N (340)
AVERAGE WIND SPEED 4.0
SKY COVER
AVERAGE SKY COVER 0.8
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
HEAVY RAIN
RAIN
LIGHT RAIN
FOG
RELATIVE HUMIDITY (PERCENT)
HIGHEST 100 5:00 AM
LOWEST 67 4:00 PM
AVERAGE 84
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 81 95 1998
2019
MINIMUM TEMPERATURE (F) 60 40 1967
SUNRISE AND SUNSET
SEPTEMBER 12 2026.....SUNRISE 6:49 AM EDT SUNSET 7:23 PM EDT
SEPTEMBER 13 2026.....SUNRISE 6:49 AM EDT SUNSET 7:21 PM EDT
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
$$Product id iem:CDUS41-KLWX-112121:IAD:2026-09-11:interim · iem-afos · IEM archive
SHA-256 48ebe499031204715c3696179c591c488b07d37060f8553050d8f5166cf901cc
Product text
CDUS41 KLWX 112121
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
521 PM EDT FRI SEP 11 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 11 2026...
VALID TODAY AS OF 0500 PM LOCAL TIME.
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1960 TO 2026
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...................................................................
TEMPERATURE (F)
TODAY
MAXIMUM 79 3:52 PM 99 1983 81 -2 84
MINIMUM 68 6:03 AM 40 1976 60 8 58
AVERAGE 74 70 4 71
PRECIPITATION (IN)
TODAY 0.56 1.45 2023 0.13 0.43 T
MONTH TO DATE 1.39 1.35 0.04 0.18
SINCE SEP 1 1.39 1.35 0.04 0.18
SINCE JAN 1 30.79 30.57 0.22 24.82
SNOWFALL (IN)
TODAY 0.0 MM MM 0.0 0.0 0.0
MONTH TO DATE 0.0 0.0 0.0 0.0
SINCE SEP 1 0.0 0.0 0.0 0.0
SINCE JUL 1 0.0 0.0 0.0 0.0
SNOW DEPTH 0
DEGREE DAYS
HEATING
TODAY 0 1 -1 0
MONTH TO DATE 0 2 -2 6
SINCE SEP 1 0 2 -2 6
SINCE JUL 1 0 3 -3 8
COOLING
TODAY 9 6 3 6
MONTH TO DATE 135 80 55 45
SINCE SEP 1 135 80 55 45
SINCE JAN 1 1415 1136 279 1193
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 12 HIGHEST WIND DIRECTION N (360)
HIGHEST GUST SPEED 16 HIGHEST GUST DIRECTION N (340)
AVERAGE WIND SPEED 4.9
SKY COVER
AVERAGE SKY COVER 0.9
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED TODAY.
HEAVY RAIN
RAIN
LIGHT RAIN
FOG
RELATIVE HUMIDITY (PERCENT)
HIGHEST 100 5:00 AM
LOWEST 67 4:00 PM
AVERAGE 84
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TOMORROW
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 81 95 1998
2019
MINIMUM TEMPERATURE (F) 60 40 1967
SUNRISE AND SUNSET
SEPTEMBER 11 2026.....SUNRISE 6:48 AM EDT SUNSET 7:24 PM EDT
SEPTEMBER 12 2026.....SUNRISE 6:49 AM EDT SUNSET 7:23 PM EDT
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
$$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/2026-09-11 with links to the NWS product and the IEM archive. A CORRECTED re-issue published before the settlement time supersedes earlier issues.
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.
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.