NWS CLI archive · settlement source
CLIIAD · 워싱턴 D.C. · America/New_York · ← 2026-09-14 · 2026-09-16 → · All dates for KIAD · JSON · METAR-derived record
Final issued 2026-09-16 02:25:00 EDT · Product id iem:CDUS41-KLWX-160625:IAD:2026-09-15:final · IEM archive
Product id iem:CDUS41-KLWX-160625:IAD:2026-09-15:final · iem-afos · IEM archive
SHA-256 e4e4fa046d7ad10a26d59b0eea3239734a02fed23ebe3ad0116c948890c3649b
Product text
CDUS41 KLWX 160625
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
225 AM EDT WED SEP 16 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 15 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 77 2:53 PM 95 1993 80 -3 84
1998
MINIMUM 52 6:04 AM 38 1985 58 -6 59
AVERAGE 65 69 -4 72
PRECIPITATION (IN)
YESTERDAY 0.00 1.06 1981 0.14 -0.14 0.00
MONTH TO DATE 1.42 1.89 -0.47 0.18
SINCE SEP 1 1.42 1.89 -0.47 0.18
SINCE JAN 1 30.82 31.11 -0.29 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 6 -6 6
SINCE SEP 1 0 6 -6 6
SINCE JUL 1 0 7 -7 8
COOLING
YESTERDAY 0 5 -5 7
MONTH TO DATE 162 102 60 69
SINCE SEP 1 162 102 60 69
SINCE JAN 1 1442 1158 284 1217
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 10 HIGHEST WIND DIRECTION SE (130)
HIGHEST GUST SPEED 15 HIGHEST GUST DIRECTION S (190)
AVERAGE WIND SPEED 2.9
SKY COVER
AVERAGE SKY COVER 0.1
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
NO SIGNIFICANT WEATHER WAS OBSERVED.
RELATIVE HUMIDITY (PERCENT)
HIGHEST 89 6:00 AM
LOWEST 43 12:00 PM
AVERAGE 66
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 79 97 1991
MINIMUM TEMPERATURE (F) 58 37 1984
SUNRISE AND SUNSET
SEPTEMBER 16 2026.....SUNRISE 6:52 AM EDT SUNSET 7:16 PM EDT
SEPTEMBER 17 2026.....SUNRISE 6:53 AM EDT SUNSET 7:15 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-152129:IAD:2026-09-15:interim · iem-afos · IEM archive
SHA-256 bac90c206cd72cda589084f3ee6ddb29bd8f26df6e5a943873446f325f780374
Product text
CDUS41 KLWX 152129
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
529 PM EDT TUE SEP 15 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 15 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 77 2:53 PM 95 1993 80 -3 84
1998
MINIMUM 52 6:04 AM 38 1985 58 -6 59
AVERAGE 65 69 -4 72
PRECIPITATION (IN)
TODAY 0.00 1.06 1981 0.14 -0.14 0.00
MONTH TO DATE 1.42 1.89 -0.47 0.18
SINCE SEP 1 1.42 1.89 -0.47 0.18
SINCE JAN 1 30.82 31.11 -0.29 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 6 -6 6
SINCE SEP 1 0 6 -6 6
SINCE JUL 1 0 7 -7 8
COOLING
TODAY 0 5 -5 7
MONTH TO DATE 162 102 60 69
SINCE SEP 1 162 102 60 69
SINCE JAN 1 1442 1158 284 1217
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 10 HIGHEST WIND DIRECTION SE (130)
HIGHEST GUST SPEED 15 HIGHEST GUST DIRECTION S (190)
AVERAGE WIND SPEED 2.2
SKY COVER
AVERAGE SKY COVER 0.1
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED TODAY.
NO SIGNIFICANT WEATHER WAS OBSERVED.
RELATIVE HUMIDITY (PERCENT)
HIGHEST 89 6:00 AM
LOWEST 43 12:00 PM
AVERAGE 66
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TOMORROW
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 79 97 1991
MINIMUM TEMPERATURE (F) 58 37 1984
SUNRISE AND SUNSET
SEPTEMBER 15 2026.....SUNRISE 6:51 AM EDT SUNSET 7:18 PM EDT
SEPTEMBER 16 2026.....SUNRISE 6:52 AM EDT SUNSET 7:16 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/2026-09-15 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.