Meteorology · activity vs. conditions

Does the weather actually move the needle?

Daily detection totals from Birdramon, lined up against day-resolution historical weather for the station's location — via Open-Meteo's free, no-key historical archive (ERA5 reanalysis). No account, no subscription tier.

Correlation, last 30 days

30 days with both a detection count and matching weather
essentially no negative correlation (r = -0.09) Daily high temp ↔ detections
a weak negative correlation (r = -0.28) Precipitation ↔ detections
essentially no negative correlation (r = -0.02) Peak wind ↔ detections

A rough read, not a study: Pearson's r across whichever days in this window have both a detection count and weather on file. Small windows (30 days) can swing around on a couple of unusual days — the longer windows are the more trustworthy read on the actual pattern.

Activity vs. conditions

tap a variable to change the overlay

Busiest days

most detections, with the weather that day

2026-08-06

Dense drizzle · 31.0°C / 21.2°C · 1.6mm
479 det · 15 sp

2026-08-07

Light rain · 30.1°C / 21.7°C · 6.8mm
417 det · 13 sp

2026-08-05

Light drizzle · 30.0°C / 19.9°C · 0.8mm
402 det · 15 sp

2026-08-26

Overcast · 28.5°C / 16.2°C
386 det · 16 sp

2026-08-24

Overcast · 26.8°C / 15.1°C
363 det · 12 sp

Quietest days

fewest detections, with the weather that day

2026-08-28

Light drizzle · 28.8°C / 19.2°C · 0.2mm
83 det · 11 sp

2026-08-17

Rain · 28.8°C / 22.2°C · 16.4mm
94 det · 12 sp

2026-08-16

Dense drizzle · 34.1°C / 24.6°C · 4.5mm
103 det · 11 sp

2026-08-12

Rain · 26.8°C / 19.2°C · 17.9mm
127 det · 10 sp

2026-08-15

Light rain · 33.1°C / 22.9°C · 4.2mm
192 det · 17 sp

Heads up: Open-Meteo's historical archive lags a handful of days behind "now" (it's reanalysis data, not live observations), so the most recent few days in this window may not have a weather row yet — that's expected, not a bug.