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Basic parameters of the analysed research stations which are arranged in the west-east direction; TN – tropical night_
| Station | Longitude | Latitude | Altitude [m a.s.l.] | TN/10 years growth |
|---|---|---|---|---|
| Szczecin | 14°37'22" | 53°23'43" | 1 | 0.12 |
| Gorzów Wielkopolski | 15°16'38" | 52°44'28" | 71 | 0.50 |
| Zielona Góra | 15°31'28" | 51°55'49" | 192 | 0.51 |
| Poznań | 16°50'09" | 52°25'02" | 88 | 0.46 |
| Wrocław | 16°54'00" | 51°06'12" | 120 | 0.25 |
| Opole | 17°58'08" | 50°37'37" | 163 | 0.30 |
| Gdańsk | 18°29'12" | 54°22'16" | 7 | 0.41 |
| Toruń | 18°35'43" | 53°02'31" | 69 | 0.32 |
| Katowice | 19°01'58" | 50°14'26" | 278 | 0.08 |
| Łódź | 19°23'59" | 51°43'24" | 174 | 0.06 |
| Kraków | 19°48'07" | 50°04'49" | 236 | 0.00 |
| Olsztyn | 20°25'22" | 53°46'16" | 133 | 0.06 |
| Kielce | 20°41'32" | 50°48'37" | 260 | 0.03 |
| Warszawa | 20°57'40" | 52°09'46" | 106 | 0.42 |
| Rzeszów | 22°02'32" | 50°06'39" | 206 | 0.34 |
| Lublin | 22°23'37" | 51°13'01" | 238 | 0.02 |
| Białystok | 23°09'44" | 53°06'26" | 148 | 0.11 |
Tropical nights (TNs) divided by month in individual decades (1951–2020) and years 2021–2024_
| Decade | Month | |||||
|---|---|---|---|---|---|---|
| May | June | July | August | September | Sum | |
| 1951–1960 | 0 | 4 | 18 | 5 | 0 | 27 |
| 1961–1970 | 0 | 4 | 11 | 16 | 0 | 31 |
| 1971–1980 | 0 | 3 | 15 | 10 | 0 | 28 |
| 1981–1990 | 1 | 3 | 33 | 13 | 0 | 50 |
| 1991–2000 | 0 | 9 | 38 | 45 | 0 | 92 |
| 2001–2010 | 1 | 10 | 117 | 25 | 0 | 153 |
| 2011–2020 | 0 | 45 | 86 | 116 | 11 | 258 |
| 2021–2024 | 0 | 35 | 62 | 47 | 4 | 148 |
| Sum | 2 | 113 | 380 | 277 | 15 | 787 |
| Percentage | 0.25 | 14.36 | 48.28 | 35.20 | 1.91 | 100 |
Duration of tropical nights in stations which are arranged in the west-east direction_
| Station | Duration | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 day | 2 days | 3 days | 4 days | 5 days | 6 days | 7 days | 8 days | 9 days | Number of periods | Total days | |
| Szczecin | 44 | 1 | 45 | 47 | |||||||
| Gorzów Wielkopolski | 45 | 10 | 2 | 57 | 71 | ||||||
| Zielona Góra | 77 | 20 | 7 | 1 | 2 | 1 | 108 | 161 | |||
| Poznań | 50 | 10 | 1 | 61 | 73 | ||||||
| Wrocław | 33 | 1 | 34 | 35 | |||||||
| Opole | 37 | 4 | 41 | 45 | |||||||
| Gdańsk | 30 | 10 | 3 | 1 | 1 | 1 | 46 | 75 | |||
| Toruń | 41 | 6 | 2 | 49 | 59 | ||||||
| Katowice | 19 | 19 | 19 | ||||||||
| Łódź | 30 | 3 | 33 | 36 | |||||||
| Kraków | 11 | 1 | 12 | 13 | |||||||
| Olsztyn | 20 | 3 | 23 | 26 | |||||||
| kielce | 9 | 9 | 9 | ||||||||
| Warszawa | 41 | 6 | 3 | 50 | 62 | ||||||
| Rzeszów | 27 | 3 | 30 | 33 | |||||||
| Lublin | 15 | 15 | 15 | ||||||||
| Białystok | 8 | 8 | 8 | ||||||||
| Sum | 537 | 77 | 19 | 2 | 3 | 0 | 1 | 0 | 1 | 640 | 787 |
Tropical nights divided by month at individual synoptic stations_
| Station | Month | |||||
|---|---|---|---|---|---|---|
| May | June | July | August | September | Sum | |
| Szczecin | 0 | 5 | 24 | 16 | 2 | 47 |
| Gorzów Wielkopolski | 0 | 10 | 34 | 25 | 2 | 71 |
| Zielona Góra | 1 | 26 | 73 | 59 | 2 | 161 |
| Poznań | 0 | 13 | 34 | 24 | 2 | 73 |
| Wrocław | 0 | 6 | 13 | 15 | 1 | 35 |
| Opole | 0 | 4 | 23 | 16 | 2 | 45 |
| Gdańsk | 0 | 1 | 38 | 36 | 0 | 75 |
| Toruń | 0 | 14 | 23 | 20 | 2 | 59 |
| Katowice | 0 | 4 | 10 | 5 | 0 | 19 |
| Łódź | 0 | 4 | 20 | 12 | 0 | 36 |
| Kraków | 0 | 2 | 7 | 4 | 0 | 13 |
| Olsztyn | 1 | 5 | 13 | 6 | 1 | 26 |
| Kielce | 0 | 3 | 3 | 3 | 0 | 9 |
| Warszawa | 0 | 10 | 31 | 21 | 0 | 62 |
| Rzeszów | 0 | 3 | 21 | 8 | 1 | 33 |
| Lublin | 0 | 2 | 7 | 6 | 0 | 15 |
| Białystok | 0 | 1 | 6 | 1 | 0 | 8 |
| Sum | 2 | 113 | 380 | 277 | 15 | 787 |
| Percentage | 0.25 | 14.36 | 48.28 | 35.20 | 1.91 | 100.00 |