NWS CLI archive · settlement source
CLIIAD · 워싱턴 D.C. · America/New_York · ← 2026-09-18 · 2026-09-20 → · All dates for KIAD · JSON · METAR-derived record
Final issued 2026-09-20 02:30:00 EDT · Product id iem:CDUS41-KLWX-200630:IAD:2026-09-19:final · IEM archive
Product id iem:CDUS41-KLWX-200630:IAD:2026-09-19:final · iem-afos · IEM archive
SHA-256 995348a9d2d131768dff51890bd9603ad1d26a9f1031d9dad67f529ef21910e5
Product text
CDUS41 KLWX 200630
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
230 AM EDT SUN SEP 20 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 19 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 2:07 PM 93 1977 78 1 89
1978
MINIMUM 65 7:22 AM 36 1984 57 8 56
AVERAGE 72 68 4 73
PRECIPITATION (IN)
YESTERDAY 0.00 1.26 2000 0.14 -0.14 0.00
MONTH TO DATE 1.56 2.47 -0.91 1.05
SINCE SEP 1 1.56 2.47 -0.91 1.05
SINCE JAN 1 30.96 31.69 -0.73 25.69
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 2 -2 0
MONTH TO DATE 0 12 -12 7
SINCE SEP 1 0 12 -12 7
SINCE JUL 1 0 13 -13 9
COOLING
YESTERDAY 7 4 3 8
MONTH TO DATE 176 120 56 88
SINCE SEP 1 176 120 56 88
SINCE JAN 1 1456 1176 280 1236
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 13 HIGHEST WIND DIRECTION NE (30)
HIGHEST GUST SPEED 17 HIGHEST GUST DIRECTION NE (30)
AVERAGE WIND SPEED 6.5
SKY COVER
AVERAGE SKY COVER 0.7
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
NO SIGNIFICANT WEATHER WAS OBSERVED.
RELATIVE HUMIDITY (PERCENT)
HIGHEST 76 7:00 AM
LOWEST 60 4:00 PM
AVERAGE 68
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 78 91 1965
MINIMUM TEMPERATURE (F) 56 40 1979
SUNRISE AND SUNSET
SEPTEMBER 20 2026.....SUNRISE 6:56 AM EDT SUNSET 7:10 PM EDT
SEPTEMBER 21 2026.....SUNRISE 6:57 AM EDT SUNSET 7:08 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-192137:IAD:2026-09-19:interim · iem-afos · IEM archive
SHA-256 80ffc5d04983e3be1046e716f512fccb287be1deab61601d7911f4e26d08d5eb
Product text
CDUS41 KLWX 192137
CLIIAD
CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
537 PM EDT SAT SEP 19 2026
...................................
...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR SEPTEMBER 19 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 2:07 PM 93 1977 78 1 89
1978
MINIMUM 65 7:22 AM 36 1984 57 8 56
AVERAGE 72 68 4 73
PRECIPITATION (IN)
TODAY 0.00 1.26 2000 0.14 -0.14 0.00
MONTH TO DATE 1.56 2.47 -0.91 1.05
SINCE SEP 1 1.56 2.47 -0.91 1.05
SINCE JAN 1 30.96 31.69 -0.73 25.69
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 2 -2 0
MONTH TO DATE 0 12 -12 7
SINCE SEP 1 0 12 -12 7
SINCE JUL 1 0 13 -13 9
COOLING
TODAY 7 4 3 8
MONTH TO DATE 176 120 56 88
SINCE SEP 1 176 120 56 88
SINCE JAN 1 1456 1176 280 1236
...................................................................
WIND (MPH)
HIGHEST WIND SPEED 13 HIGHEST WIND DIRECTION NE (30)
HIGHEST GUST SPEED 17 HIGHEST GUST DIRECTION NE (30)
AVERAGE WIND SPEED 6.2
SKY COVER
AVERAGE SKY COVER 0.7
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED TODAY.
NO SIGNIFICANT WEATHER WAS OBSERVED.
RELATIVE HUMIDITY (PERCENT)
HIGHEST 76 7:00 AM
LOWEST 60 4:00 PM
AVERAGE 68
..........................................................
THE WASHINGTON DULLES DC CLIMATE NORMALS FOR TOMORROW
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 78 91 1965
MINIMUM TEMPERATURE (F) 56 40 1979
SUNRISE AND SUNSET
SEPTEMBER 19 2026.....SUNRISE 6:55 AM EDT SUNSET 7:12 PM EDT
SEPTEMBER 20 2026.....SUNRISE 6:56 AM EDT SUNSET 7:10 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/2026-09-19 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.