Every heat event the pipeline tracked between 2017-05-01 and 2017-09-30, with how each one grew, peaked and moved. Anomalies are against the 1991–2020 baseline.
Season at a glance
Events tracked
21
Total heat burden
78.76 Mkm²·days
Longest
21days (#4)
Hottest
+15.1°C (#4)
With a heat dome
9of 21 events
A heat dome is the stricter object: a tracked heat event with a closed 500 hPa anticyclone whose influence cap overlies it, after Loikith et al. (2026). Most heatwaves are not domes, so the label is a finding and not a synonym.
ERA5 daily maximum 2 m temperature over land, against the 1991–2020 climatology (p90 in a centred 15-day window). A heatwave cell is Tx above p90 on at least 3 consecutive days.
When the events ran
Overlapping bars are concurrent events in different places, not one event counted twice: each is a separately labelled cluster of contiguous heatwave cells.
How each event evolved
Event #12 — 2017-07-27 → 2017-08-15 20 daysheat dome · 12/20 d · Z500 +164 m
peak 1.96 M km² on 2017-08-04 · max +12.2 °C · mean +6.5 °C · burden 17.82 M km²·d · drift 494 km (39.8 N 41.0 E → 43.1 N 37.1 E)
Event #20 — 2017-09-08 → 2017-09-24 17 daysheat dome · 9/17 d · Z500 +191 m
peak 1.74 M km² on 2017-09-18 · max +14.0 °C · mean +7.3 °C · burden 16.97 M km²·d · drift 1448 km (42.7 N 26.1 E → 40.3 N 43.2 E)
Event #4 — 2017-06-07 → 2017-06-27 21 daysheat dome · 13/21 d · Z500 +225 m
peak 1.19 M km² on 2017-06-21 · max +15.1 °C · mean +8.1 °C · burden 10.94 M km²·d · drift 1388 km (39.6 N -3.1 E → 42.8 N 13.0 E)
Event #6 — 2017-06-23 → 2017-07-08 16 daysheat dome · 10/16 d · Z500 +155 m
peak 1.32 M km² on 2017-07-02 · max +12.6 °C · mean +6.2 °C · burden 8.61 M km²·d · drift 2096 km (40.6 N 21.0 E → 35.4 N 44.1 E)
Event #2 — 2017-05-20 → 2017-06-03 15 daysheat dome · 10/15 d · Z500 +234 m
peak 1.01 M km² on 2017-05-28 · max +13.8 °C · mean +7.8 °C · burden 5.49 M km²·d · drift 1442 km (37.4 N -3.6 E → 45.1 N 10.3 E)
Event #15 — 2017-08-16 → 2017-08-25 10 dayshigh on 5/10 d only
peak 1.30 M km² on 2017-08-20 · max +11.6 °C · mean +7.8 °C · burden 5.48 M km²·d · drift 1995 km (50.2 N 28.1 E → 66.1 N 44.3 E)
Event #7 — 2017-07-04 → 2017-07-15 12 daysno overlying high
peak 643k km² on 2017-07-07 · max +10.6 °C · mean +6.4 °C · burden 3.48 M km²·d · drift 1893 km (47.4 N -1.6 E → 39.3 N 19.1 E)
Event #9 — 2017-07-10 → 2017-07-19 10 dayshigh on 2/10 d only
peak 286k km² on 2017-07-13 · max +10.3 °C · mean +6.2 °C · burden 1.45 M km²·d · drift 381 km (38.7 N -1.9 E → 42.2 N -2.1 E)
Event #18 — 2017-08-25 → 2017-08-30 6 daysheat dome · 4/6 d · Z500 +128 m
peak 263k km² on 2017-08-28 · max +12.4 °C · mean +8.1 °C · burden 938k km²·d · drift 138 km (46.7 N 4.9 E → 46.9 N 6.7 E)
Event #19 — 2017-08-28 → 2017-09-07 11 daysno overlying high
peak 165k km² on 2017-09-05 · max +10.9 °C · mean +5.9 °C · burden 819k km²·d · drift 276 km (40.4 N 42.3 E → 38.8 N 44.8 E)
Event #11 — 2017-07-19 → 2017-07-24 6 dayshigh on 1/6 d only
peak 226k km² on 2017-07-22 · max +10.6 °C · mean +6.6 °C · burden 811k km²·d · drift 257 km (45.4 N 18.4 E → 43.6 N 20.5 E)
Event #14 — 2017-08-15 → 2017-08-26 12 dayshigh on 2/12 d only
peak 131k km² on 2017-08-21 · max +11.1 °C · mean +5.2 °C · burden 766k km²·d · drift 208 km (38.6 N -2.9 E → 40.0 N -1.4 E)
Event #3 — 2017-05-22 → 2017-05-28 7 daysheat dome · 5/7 d · Z500 +234 m
peak 206k km² on 2017-05-26 · max +11.9 °C · mean +7.5 °C · burden 723k km²·d · drift 114 km (53.3 N -0.8 E → 54.4 N -1.1 E)
Event #5 — 2017-06-16 → 2017-06-24 9 daysheat dome · 7/9 d · Z500 +225 m
peak 168k km² on 2017-06-18 · max +11.7 °C · mean +8.2 °C · burden 711k km²·d · drift 615 km (57.3 N -2.3 E → 52.1 N 1.4 E)
Event #10 — 2017-07-15 → 2017-07-23 9 daysno overlying high
peak 131k km² on 2017-07-19 · max +9.2 °C · mean +4.7 °C · burden 683k km²·d · drift 386 km (40.0 N 40.0 E → 38.1 N 43.8 E)
Event #13 — 2017-08-02 → 2017-08-08 7 dayshigh on 2/7 d only
peak 200k km² on 2017-08-05 · max +7.7 °C · mean +5.1 °C · burden 678k km²·d · drift 740 km (42.2 N 2.3 E → 37.2 N -3.4 E)
Event #8 — 2017-07-07 → 2017-07-15 9 daysno overlying high
peak 172k km² on 2017-07-12 · max +11.0 °C · mean +6.0 °C · burden 666k km²·d · drift 522 km (36.8 N 10.8 E → 35.3 N 5.3 E)
Event #21 — 2017-09-22 → 2017-09-30 9 daysheat dome · 5/9 d · Z500 +403 m
peak 118k km² on 2017-09-26 · max +10.3 °C · mean +5.4 °C · burden 616k km²·d · drift 70 km (66.8 N 14.4 E → 67.2 N 15.6 E)
Event #1 — 2017-05-14 → 2017-05-17 4 dayshigh on 2/4 d only
peak 143k km² on 2017-05-15 · max +10.6 °C · mean +7.3 °C · burden 430k km²·d · drift 265 km (43.1 N 2.9 E → 44.5 N 0.1 E)
Event #16 — 2017-08-20 → 2017-08-25 6 daysno overlying high
peak 101k km² on 2017-08-22 · max +8.2 °C · mean +4.7 °C · burden 362k km²·d · drift 274 km (40.2 N 41.2 E → 38.4 N 43.3 E)
Event #17 — 2017-08-25 → 2017-08-28 4 dayshigh on 1/4 d only
peak 107k km² on 2017-08-26 · max +11.2 °C · mean +7.4 °C · burden 326k km²·d · drift 236 km (44.8 N 17.5 E → 42.8 N 18.4 E)
Filled area is the event footprint in km² (left axis); the solid line is the peak anomaly inside it and the dashed line the mean (right axis). The small panel is the centroid path, circles sized by area and the ring marking day one. Drift is the straight-line start-to-end distance, so a dome that wandered and returned reports a small number.