Supplement of Geosci. Model Dev., 13, 2631–2644, 2020https://doi.org/10.5194/gmd-13-2631-2020-supplement© Author(s) 2020. This work is distributed underthe Creative Commons Attribution 4.0 License.

Supplement of

RainNet v1.0: a convolutional neural network for radar-based precipita-tion nowcastingGeorgy Ayzel et al.

Correspondence to: Georgy Ayzel (ayzel@uni-potsdam.de)

The copyright of individual parts of the supplement might differ from the CC BY 4.0 License.

S1 Results of verification experiments on individual events

For the analysis, we have selected 11 events during the summer periods of 2016 and 2017. These events are selected forcovering a range of event characteristics with different rainfall intensity, spatial coverage, and duration. Table S1 shows theanalyzed events as provided in Ayzel et al. (2019).

Table S1. Characteristics of the selected events

Event # Start End Duration, hours Maximum extent, km2 Extent >1 mm h−1, %

Event 1 2016-05-23 2:00 2016-05-23 8:00 6 159318 42Event 2 2016-05-23 13:00 2016-05-24 2:30 13.5 135272 56Event 3 2016-05-29 12:05 2016-05-29 23:55 12 160095 72Event 4 2016-06-12 7:00 2016-06-12 19:00 12 150416 53Event 5 2016-07-13 17:30 2016-07-14 1:00 7.5 145501 62Event 6 2016-08-04 18:00 2016-08-05 7:00 13 168407 74Event 7 2017-06-29 3:00 2017-06-29 5:05 2 140021 70Event 8 2017-06-29 17:00 2017-06-29 21:00 4 182561 60Event 9 2017-06-29 22:00 2017-06-30 21:00 23 160822 75Event 10 2017-07-21 19:00 2017-07-21 23:00 4 63698 77Event 11 2017-07-24 8:00 2017-07-25 23:55 16 253666 63

We use three metrics for model verification: mean absolute error (MAE), critical success index (CSI), and fractions skill5score (FSS). We have applied threshold rain rates of 0.125, 1, 5, 10 and 15 mm h−1 for calculating CSI and FSS. Additionally,for calculating FSS we use neighborhood (window) sizes of 1, 5, 10, and 20 km. Table S2 shows the numbers of correspondingfigures which represent verification results averaged for the particular event and metric.

Table S2. Reference to the figure numbers for analysed events and verification metrics

Event # MAE and CSI FSS

Event 1 S1 S12Event 2 S2 S13Event 3 S3 S14Event 4 S4 S15Event 5 S5 S16Event 6 S6 S17Event 7 S7 S18Event 8 S8 S19Event 9 S9 S20Event 10 S10 S21Event 11 S11 S22

1

10 20 30 40 50 60Lead time, min

0.10

0.15

0.20

0.25

0.30

0.35

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

0.5

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S1. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 1 (2016-05-23 2:00 – 2016-05-23 8:00)

2

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.5

0.6

0.7

0.8

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.3

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.0

0.1

0.2

0.3

0.4

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S2. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 2 (2016-05-23 13:00 – 2016-05-24 2:30)

3

10 20 30 40 50 60Lead time, min

0.3

0.4

0.5

0.6

0.7

0.8

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.5

0.6

0.7

0.8

0.9

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.050.100.150.200.250.300.350.400.45

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.0

0.1

0.2

0.3

0.4

0.5

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S3. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 3 (2016-05-29 12:05 – 2016-05-29 23:55)

4

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.3

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

0.5

0.6

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.05

0.10

0.15

0.20

0.25

0.30

0.35

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

0.30

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S4. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 4 (2016-06-12 7:00 – 2016-06-12 19:00)

5

10 20 30 40 50 60Lead time, min

0.15

0.20

0.25

0.30

0.35

0.40

0.45

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.500.550.600.650.700.750.800.850.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

0.5

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S5. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 5 (2016-07-13 17:30 – 2016-07-14 1:00)

6

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.50

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.0500.0750.1000.1250.1500.1750.2000.2250.250

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

0.30

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S6. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 6 (2016-08-04 18:00 – 2016-08-05 7:00)

7

10 20 30 40 50 60Lead time, min

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50M

AE, m

mh

1MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.60

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.05

0.10

0.15

0.20

0.25

0.30

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S7. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 7 (2017-06-29 3:00 – 2017-06-29 5:05)

8

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

0.30

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S8. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 8 (2017-06-29 17:00 – 2017-06-29 21:00)

9

10 20 30 40 50 60Lead time, min

0.10

0.15

0.20

0.25

0.30

0.35

0.40

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.45

0.50

0.55

0.60

0.65

0.70

0.75

0.80

0.85

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

0.5

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S9. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 9 (2017-06-29 22:00 – 2017-06-30 21:00)

10

10 20 30 40 50 60Lead time, min

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

0.9

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.3

0.4

0.5

0.6

0.7

0.8

0.9

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

0.7

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.0

0.1

0.2

0.3

0.4

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S10. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 10 (2017-07-21 19:00 – 2017-07-21 23:00)

11

10 20 30 40 50 60Lead time, min

0.2

0.3

0.4

0.5

0.6

MAE

, mm

h1

MAE

RainNetRainymotionPersistence

10 20 30 40 50 60Lead time, min

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

CSI

CSI threshold: 0.125 mm h 1

10 20 30 40 50 60Lead time, min

0.4

0.5

0.6

0.7

0.8

CSI

CSI threshold: 1 mm h 1

10 20 30 40 50 60Lead time, min

0.1

0.2

0.3

0.4

0.5

CSI

CSI threshold: 5 mm h 1

10 20 30 40 50 60Lead time, min

0.05

0.10

0.15

0.20

0.25

CSI

CSI threshold: 10 mm h 1

10 20 30 40 50 60Lead time, min

0.00

0.05

0.10

0.15

0.20

CSI

CSI threshold: 15 mm h 1

RainNetRainymotionPersistence

Figure S11. Mean Absolute Error (MAE) and Critical Success Index (CSI) for five different intensity thresholds (0.125 mm h−1, 1 mm h−1,5 mm h−1, 10 mm h−1, 15 mm h−1). The metrics are shown as a function of lead time. All values represent the average of the correspondingmetric over Event 11 (2017-07-24 8:00 – 2017-07-25 23:55)

12

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.38 0.37

0.98 0.92 0.79 0.67

0.99 0.96 0.85 0.73

0.97 0.88 0.77

0.91 0.84 0.68

0.97

0.99

0.99 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.09 0.03

0.52 0.26 0.09

0.61 0.36 0.15

0.7 0.46 0.24

0.78 0.62 0.33

0.86 0.78

0.9 0.84

0.93 0.89

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.03

0.76 0.3 0.08

0.8 0.38 0.13 0.02

0.85 0.47 0.21 0.06

0.68 0.49 0.18 0

0.61 0

0.68

0.75

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.92 0.87 0.69 0.36 0.36

0.97 0.97 0.91 0.66 0.55

0.98 0.99 0.94 0.69 0.57

0.99 0.99 0.96 0.7 0.58

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.8 0.68 0.35

0.87 0.79

0.85

0.9

0.05 0

0.5 0.13 0

0.9 0.57 0.16 0

0.93 0.65 0.2 0.01

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.54 0.19

0.63

0.68 0.02 0

0.73 0.26 0.05 0

0.76 0.68 0.3 0.06 0

0.81 0.75 0.36 0.08 0

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S12. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 1 (2016-05-23 2:00 – 2016-05-23 8:00)

13

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.9 0.88

0.98 0.95 0.94

0.99 0.97 0.96

0.92 0.89 0.78 0.57 0.59

0.98 0.98 0.95

0.99 0.99

0.99 1

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.29 0.22

0.69 0.52 0.41

0.77 0.63 0.53

0.85 0.75 0.66

0.8 0.72 0.52

0.89 0.84

0.92 0.89

0.95 0.93

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.09

0.8 0.71 0.3 0.17

0.84 0.77 0.59 0.38 0.24

0.88 0.83 0.68 0.5 0.37

0.71 0.6 0.39 0.16

0.51

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.93 0.91 0.81 0.59 0.62

0.98 0.98 0.95 0.86 0.86

0.99 0.99 0.97 0.9 0.91

0.99 1 0.98 0.92 0.93

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.83 0.75 0.55

0.85

0.27 0.05

0.89 0.68 0.41 0.09

0.92 0.89 0.74 0.48 0.11

0.95 0.93 0.81 0.56 0.13

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.42 0.180.71 0.6 0.06

0.77 0.68 0.51 0.25 0.08

0.81 0.73 0.56 0.28 0.1

0.85 0.79 0.63 0.33 0.12

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S13. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 2 (2016-05-23 13:00 – 2016-05-24 2:30)

14

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.91

0.96 0.94

0.97 0.97

0.93 0.91 0.81 0.6 0.62

0.98 0.98 0.96 0.89

0.99 0.99 0.98

1 1 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.33 0.24

0.56 0.42

0.67 0.55

0.87 0.78 0.69

0.82 0.76 0.57

0.9 0.86 0.73

0.93 0.9 0.8

0.95 0.94

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.11

0.35 0.2

0.85 0.43 0.28

0.89 0.73 0.56 0.42

0.74 0.66 0.45 0.2

0.81 0.75 0.57

0.8 0.64

0.85

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.95 0.93 0.84 0.63 0.66

0.99 0.99 0.96 0.88 0.89

0.99 0.99 0.98 0.91 0.92

1 1 0.99 0.93 0.94

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.85 0.8 0.63

0.91 0.88 0.74

0.91

0.96

0.32 0.04

0.45 0.07

0.93 0.8 0.53 0.09

0.94 0.86 0.61 0.11

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.75 0.7 0.52 0.23

0.76 0.61

0.66

0.06

0.81 0.31 0.08

0.84 0.8 0.35 0.09

0.87 0.85 0.72 0.42 0.13

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S14. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 3 (2016-05-29 12:05 – 2016-05-29 23:55)

15

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.49

0.87 0.81

0.98 0.92 0.87

0.99 0.95 0.91

0.88 0.85 0.74 0.52

0.97 0.98 0.95

0.98 0.99

0.99 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.16 0.08

0.64 0.39 0.22

0.77 0.56 0.37

0.86 0.72 0.55

0.71 0.63 0.4

0.85 0.81

0.89 0.88

0.93 0.93

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.27 0.09 0.03

0.72 0.64 0.46 0.23 0.08

0.78 0.73 0.58 0.36 0.16

0.85 0.82 0.71 0.54 0.32

0.59 0.48

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.89 0.87 0.76

1

0.52 0.48

0.97 0.98 0.95 0.82 0.74

0.98 0.99 0.97 0.85 0.77

0.99 0.98 0.86 0.78

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.76 0.67

0.87 0.83

0.91 0.89

0.94

0.4 0.08 0

0.59 0.18 0.01

0.69 0.25 0.01

0.93 0.77 0.32 0.02

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.62 0.49 0.24 0.04 0

0.71 0.62 0.37 0.09 0

0.77 0.69 0.45 0.13 0.01

0.83 0.77 0.54 0.18 0.01

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S15. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 4 (2016-06-12 7:00 – 2016-06-12 19:00)

16

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.36 0.38

0.92 0.78 0.75

0.96 0.86 0.82

0.98 0.89 0.87

0.93 0.88 0.68

0.98 0.97

0.99 0.99

0.99 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.11 0.08

0.57 0.33 0.23

0.66 0.45 0.36

0.76 0.59 0.51

0.82 0.69 0.37

0.89 0.82

0.92 0.86

0.95 0.91

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.06 0.03

0.37 0.17 0.09

0.84 0.45 0.26 0.17

0.88 0.55 0.37 0.31

0.72 0.57 0.23

0.8 0.68

0.73

0.8

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.94 0.9 0.71

0.99 0.98

1 1

0.33 0.36

0.91 0.62 0.62

0.99 0.99 0.94 0.64 0.65

0.96 0.63 0.64

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.85 0.75 0.41

0.91 0.84

0.93 0.88

0.96 0.92

0.05 0

0.55 0.14 0

0.63 0.18 0

0.7 0.23 0

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.75 0.62 0.27

0.7

0.74

0.01 0

0.8 0.36 0.03 -0

0.83 0.41 0.04 -0

0.87 0.8 0.48 0.06 0

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S16. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 5 (2016-07-13 17:30 – 2016-07-14 1:00)

17

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.4

0.83 0.78

0.9 0.86

0.99 0.94 0.9

0.96 0.93 0.77 0.44

0.99 0.98 0.95

0.99 0.99 0.97

1 1

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.12

0.43 0.25

0.52 0.34

0.84 0.63 0.44

0.89 0.82 0.54 0.19

0.93 0.89 0.7

0.95 0.92 0.76

0.97 0.95

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.04

0.22 0.1

0.29 0.14

0.68 0.38 0.2

0.83 0.75 0.41 0.1

0.88 0.82 0.53

0.9 0.85 0.59

0.93 0.89

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.94 0.81

0.99

0.96 0.39 0.44

0.99 0.95 0.7 0.68

0.99 0.99 0.97 0.75 0.72

1 1 0.98 0.78 0.73

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.91 0.86 0.62 0.24

0.94 0.91 0.72

0.93 0.77

0.96

0.01

0.4 0.02

0.95 0.46 0.03

0.97 0.83 0.54 0.05

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.86 0.81 0.5 0.14

0.89 0.86 0.57

0.88 0.6

0.91

0.01

0.21 0.01

0.9 0.23 0.02

0.93 0.65 0.28 0.03

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S17. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 6 (2016-08-04 18:00 – 2016-08-05 7:00)

18

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.84 0.82

0.91 0.89

0.94 0.94

0.96 0.94 0.78 0.43 0.42

0.99 0.99 0.96

0.99 0.99 0.98

1 1 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.08

0.38 0.23

0.83 0.53 0.39

0.9 0.7 0.59

0.89 0.85 0.55 0.14

0.94 0.92 0.75

0.96 0.95

0.98 0.97

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.02

0.2 0.07

0.67 0.32 0.14

0.95 0.93 0.76 0.5 0.31

0.85 0.79 0.42 0.07

0.9 0.86 0.59

0.92 0.89

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.95 0.82 0.46

1

0.96 0.42

0.99 0.99 0.96 0.78 0.75

0.99 0.98 0.83 0.8

1 1 0.99 0.85 0.81

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.91 0.88 0.63

0.95 0.93 0.76

0.14 0.01

0.29 0.02

0.96 0.95 0.82 0.37 0.04

0.98 0.97 0.88 0.5 0.05

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.87 0.82 0.51 0.11

0.87 0.61

0.01

0.9 0.18 0.03

0.92 0.89 0.66 0.21 0.05

0.94 0.92 0.73 0.28 0.08

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S18. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 7 (2017-06-29 3:00 – 2017-06-29 5:05)

19

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.49

0.86 0.83

0.92 0.9

0.99 0.95 0.93

0.94 0.91 0.75 0.49

0.99 0.98 0.94

0.99 0.99 0.97

1 1

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.13 0.08

0.64 0.33 0.23

0.74 0.47 0.37

0.83 0.63 0.53

0.85 0.76 0.44

0.91 0.87

0.94 0.91

0.96 0.95

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.29 0.05 0.02

0.76 0.43 0.13 0.06

0.81 0.52 0.21 0.12

0.87 0.63 0.36 0.24

0.78 0.66

0.84

0.88

0.91

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.95 0.93 0.78 0.5

0.99 0.95

0.48

0.99 0.81 0.77

0.99 0.99 0.97 0.85 0.81

1 1 0.98 0.86 0.82

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.88 0.8 0.46

0.93 0.88

0.95 0.92

0.97

0.06 0

0.61 0.14 0

0.69 0.19 0

0.95 0.78 0.25 0.01

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.81 0.68

0.85

0.26 0.02 0

0.75 0.35 0.04 0

0.88 0.8 0.42 0.06 0

0.91 0.85 0.5 0.09 0

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S19. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 8 (2017-06-29 17:00 – 2017-06-29 21:00)

20

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.4

0.93 0.81 0.74

0.96 0.87 0.81

0.97 0.9 0.85

0.95 0.89 0.7 0.43

0.99 0.98

0.99 0.99

1 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.39 0.11 0.05

0.59 0.31 0.18

0.7 0.43 0.29

0.79 0.56 0.41

0.87 0.75

0.93 0.86

0.95 0.9

0.97 0.94

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.24 0.04 0.01

0.88 0.37 0.11 0.04

0.81 0.46 0.18 0.09

0.94 0.86 0.57 0.3 0.18

0.82 0.66

0.76

0.9

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.96 0.91 0.72 0.43 0.34

0.99 0.98 0.92 0.74 0.59

0.99 0.99 0.94 0.79 0.62

1 0.99 0.96 0.8 0.63

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.89 0.79

0.94 0.87

0.91

0.38 0.07 0.01

0.52 0.15 0.01

0.95 0.6 0.18 0.02

0.97 0.94 0.68 0.22 0.03

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.83 0.69 0.18 0.03 0

0.87 0.76 0.25 0.06 0.01

0.9 0.79 0.3 0.08 0.01

0.92 0.84 0.36 0.11 0.02

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S20. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 9 (2017-06-29 22:00 – 2017-06-30 21:00)

21

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.87

0.92 0.92

0.95 0.95

0.93 0.92 0.81 0.54 0.52

0.98 0.98 0.95 0.85

0.99 0.99 0.98

1 1 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.21 0.15

0.4 0.32

0.51 0.45

0.86 0.64 0.6

0.82 0.78 0.57

0.89 0.87 0.72

0.92 0.9 0.79

0.95 0.94

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.05

0.19 0.11

0.27 0.17

0.39 0.3

0.72 0.68 0.43 0.1

0.79 0.76 0.55

0.83 0.8 0.62

0.87 0.85 0.69

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.95 0.94 0.85 0.61 0.6

0.99 0.99 0.96 0.85 0.85

0.99 0.99 0.98 0.89 0.89

1 1 0.99 0.91 0.91

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.86 0.83 0.63

0.91 0.89 0.74

0.93 0.92

0.96 0.95

0.19 0

0.3 0

0.79 0.37 0

0.85 0.46 0

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.77 0.73 0.52 0.12

0.82 0.79 0.61

0.85 0.82 0.66

0.89 0.87 0.72

0.01

0.17 0.02

0.21 0.03

0.27 0.05

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S21. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 10 (2017-07-21 19:00 – 2017-07-21 23:00)

22

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.41 0.37

0.93 0.81 0.74

0.96 0.88 0.81

0.97 0.91 0.85

0.94 0.88 0.69

0.98 0.97

0.99 0.99

0.99 0.99

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.11 0.05

0.62 0.34 0.19

0.73 0.49 0.33

0.83 0.64 0.47

0.84 0.71 0.39

0.91 0.84

0.94 0.89

0.96 0.93

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.05 0.02

0.85 0.43 0.16 0.06

0.88 0.79 0.53 0.27 0.13

0.92 0.85 0.64 0.41 0.25

0.78 0.61 0.26

0.73

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.95 0.9 0.72

0.99 0.98

0.39 0.3

0.92 0.7 0.55

0.99 0.99 0.95 0.75 0.58

0.99 0.99 0.96 0.75 0.59

Lead time: 5 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.87 0.76 0.42

0.92 0.85

0.95

0.97

0.07 0

0.6 0.16 0.01

0.89 0.68 0.22 0.01

0.93 0.77 0.28 0.02

Lead time: 30 min

0.125 1.0 5.0 10.0 15.0Intensity threshold, mm h 1

15

1020

Spat

ials

cale

,km

0.79 0.65 0.29 0.04 0.01

0.84 0.73 0.39 0.08 0.01

0.87 0.77 0.46 0.11 0.02

0.9 0.83 0.54 0.16 0.03

Lead time: 60 min

0.0

0.2

0.4

0.6

0.8

1.0

FSS

Rainymotion

RainNet

Figure S22. Fractions Skill Score (FSS) for Rainymotion (top panel) and RainNet (bottom panel), for 5, 30, and 60 minutes lead time, andspatial window sizes of 1, 5, 10 and 20 km, and for intensity thresholds of 0.125, 1, 5, 10 and 15 mm h−1. In addition to the color code of theFSS, we added the numerical FSS values. The FSS value of the model which is significantly superior for a specific combination of windowsize, intensity threshold, and lead time is typed in bold black digits, for the inferior model in regular. All values represent the average of theFSS over Event 11 (2017-07-24 8:00 – 2017-07-25 23:55)

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References

Ayzel, G., Heistermann, M., and Winterrath, T.: Optical flow models as an open benchmark for radar-based precipitation nowcast-10ing (rainymotion v0.1), Geoscientific Model Development, 12, 1387–1402, https://doi.org/10.5194/gmd-12-1387-2019, https://www.geosci-model-dev.net/12/1387/2019/, 2019.

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