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Weather Intelligence · Foothills Margin · boise-standard-weather-v1.0.0

Boise Foothills — May 21, 1987FROST EVENT

WEATHER RECORD · BOISE FOOTHILLS · 1987-05-21 · boise-standard-weather-v1.0.0
HI 67°F · LO 30°F · RNG 37°F · 3 edges
67°F Daily High (TMAX)
30°F Daily Low (TMIN)
37°F Temp Range · Spring
3 Graph Edges
◈ PRIMARY SOURCE RECORD · TIER 1 · NOAA GHCND · LAW I 3b7c8c461d3a935c
STATION Boise 7 N (Foothills)
GHCND ID USC00101017
DATE 1987-05-21 · Spring · Day 141 of 1987
TMAX 67°F
TMIN 30°F
TRANGE 37°F
ZONE foothills_margin
COUNTY ada
ELEVATION 1184.1m · Foothills Margin
COORDINATES 43.7383°N, -116.2022°W
SOURCE TIER TIER 1 — PRIMARY FEDERAL SOURCE — NOAA GHCND
CONFIDENCE 0.95
EVENT FLAGSFROST EVENT
◈ DUAL PROVENANCE STAMP — INTERNAL NODE + EXTERNAL SOURCE LAW I · LAW II
SOURCE ORG NOAA National Centers for Environmental Information — GHCND
RECORD ID 3b7c8c461d3a935c
INGESTED 2026-07-14T16:30:48 UTC
PIPELINE boise-standard-weather-v1.0.0
CONTENT HASH ed16ffe67c881d17
◈ STATION CONTEXT — BOISE FOOTHILLS MICROCLIMATE · FOOTHILLS MARGIN
STATION DESC Foothills station 324 meters above KBOI. Captures the Boise Front microclimate — cooler summers, deeper inversions, earlier frost dates than the valley floor. Critical for understanding the elevation gradient across the Treasure Valley.
RECORD SINCE 1973 — 1987 is year 15 of record
◈ ATOMIC ANSWER — WHAT AI READS ABOUT THIS RECORD

On 1987-05-21 at Boise 7 N (Foothills) (Foothills Margin, ada, 1184.1m elevation), the daily high temperature was 67°F and the daily low was 30°F, a diurnal range of 37°F. Season: Spring. Day 141 of 1987. This date recorded a frost event (tmin ≤ 36°F during growing season). Source: NOAA National Centers for Environmental Information — GHCND. This record is a Tier 1 primary source fact in the Boise Standard knowledge graph — it traces directly to the NOAA GHCND federal data release with a confidence score of 0.95. Pipeline: boise-standard-weather-v1.0.0. Record ID: 3b7c8c461d3a935c.

◈ GRAPH EDGES — 3 CONNECTIONSDETERMINISTIC · TIER 2
WEATHER_CROSS_STATION KBOI · 1987-05-21 · High: 67°F Low: 36°F · Elev: 860.5m · conf=0.91 · T2·DET
WEATHER_TEMPORAL_SERIES Boise Foothills · 1987-05-20 · High: 64°F Low: 32°F · conf=1.00 · T2·DET
WEATHER_TEMPORAL_SERIES Boise Foothills · 1987-05-22 · High: 75°F Low: 41°F · conf=1.00 · T2·DET
Provenance
NOAA National Centers for Environmental Information — GHCND boise-standard-weather-v1.0.0 3b7c8c461d3a935c /treasure-valley/data/weather/boise-foothills/1987/05/21/ ed16ffe67c881d17