Culture · Science · The weather record
The Weather of 2015
Observations at Vellmar, with the level of the Ostra, fog on the river and the state of Lake Tarn at Tarnmund, as recorded by The Tarnmund Observatory, observing since 1869. Temperatures in degrees, rainfall in millimetres.
The months
| Month | Mean | Warmest day | Coldest night | Rain | Fog days | Frost days | Remarks |
|---|---|---|---|---|---|---|---|
| January | -0.9° | 11° | -11° | 45 mm | 8 | 23 | |
| February | 0.4° | 11° | -8° | 45 mm | 7 | 16 | Fog persistent on the lower Ostra; the ferries stopped. |
| March | 4.7° | 14° | -6° | 55 mm | 6 | 0 | Dry; dust on the Marschau road. |
| April | 10.0° | 23° | 0° | 67 mm | 5 | 0 | Dry; dust on the Marschau road. |
| May | 15.3° | 27° | 7° | 94 mm | 0 | 0 | Late frost in the Sudmark vineyards. |
| June | 18.6° | 29° | 7° | 41 mm | 0 | 0 | Thunder over the Kesselhöh on several evenings. |
| July | 20.9° | 30° | 11° | 53 mm | 0 | 0 | The Ostra fell to its summer mark. |
| August | 20.8° | 34° | 12° | 53 mm | 2 | 0 | Mosquitoes troublesome on the Reed Line. |
| September | 11.0° | 22° | -1° | 48 mm | 5 | 0 | Fog on the marsh most mornings. |
| October | 6.3° | 16° | -4° | 54 mm | 10 | 0 | Dry; dust on the Marschau road. |
| November | 1.6° | 11° | -7° | 59 mm | 14 | 8 | Hard frost on the causeway; the planks were sanded. |
| December | -1.6° | 11° | -14° | 60 mm | 8 | 28 | Snow lay in the capital for several days. |
Lake Tarn
The lake froze at Tarnmund on 14 February 2015, as the towns reported and bore the weight of a man by the end of the month; the ferry to the eastern shore was replaced by a marked path. The thaw is recorded on 11 March 2015.
The Ostra
The river rose to 1.1 metres above its mark at Vellmar bridge at the highest. 65 days of fog were recorded on the lower river, the ferries stopping when the far bank could not be seen.
The Observatory's note
The Tarnmund Observatory certifies the foregoing as the record of 2015, compiled from the Vellmar station, the lakeside station at Tarnmund and the garrison readings at Marschau. Readings on the Osmoor beyond the Reed Line are not taken. The Observatory notes that the front-line report received each evening from the War Ministry makes no mention of the weather at the front, and that none is expected.
Warmest month, 20.9°; coldest, -1.6°. Means are of the month; the warmest day and coldest night are the extremes recorded.
Weather in the public record
- 17 January 2015, Sudholt. The Ostra rises 60 centimetres above its mark at Sudholt. Cellars in Ferry Gate are flooded. Report.
- 7 February 2015, Weinau. The Ostra rises 40 centimetres above its mark at Weinau. Cellars in High Street are flooded. Report.
- 14 February 2015, Salzhafen. The coldest night in 30 years is recorded at Salzhafen. Lake Tarn freezes to the middle. Report.
- 19 March 2015, Tarnmoor. A storm strips roofs in Tarnmoor and fells the old lime in Lime Lane. Report.
- 27 March 2015, Norrbruck. The coldest night in 30 years is recorded at Norrbruck. Lake Tarn freezes to the middle. Report.
- 4 April 2015, Sanding. A storm strips roofs in Sanding and fells the old lime in Bridge Street. Report.
- 8 April 2015, Dammsee. A storm strips roofs in Dammsee and fells the old lime in New Gate Lane. Report.
- 14 April 2015, Dammsee. The Ostra rises 80 centimetres above its mark at Dammsee. Cellars in School Gate are flooded. Report.
- 26 April 2015, Tarnmoor. A storm strips roofs in Tarnmoor and fells the old lime in Lime Lane. Report.
- 3 May 2015, Norrhafen. The Ostra rises 30 centimetres above its mark at Norrhafen. Cellars in Orchard Square are flooded. Report.
- 26 June 2015, Hollhausen. A storm strips roofs in Hollhausen and fells the old lime in Ferry Street. Report.
- 16 July 2015, Norrbruck. The Ostra rises 70 centimetres above its mark at Norrbruck. Cellars in Weaver Gate are flooded. Report.
- 28 July 2015, Norrhafen. The Ostra rises 30 centimetres above its mark at Norrhafen. Cellars in Vine Walk are flooded. Report.
- 11 August 2015, Eisenheim. The coldest night in 80 years is recorded at Eisenheim. Lake Tarn freezes to the middle. Report.
- 30 August 2015, Hollhausen. A storm strips roofs in Hollhausen and fells the old lime in Ferry Square. Report.
- 22 September 2015, Salzhafen. A storm strips roofs in Salzhafen and fells the old lime in Chapel Quay. Report.
- 24 September 2015, Grauholt. The coldest night in 70 years is recorded at Grauholt. Lake Tarn freezes to the middle. Report.
- 17 November 2015, Wasserdorf. A storm strips roofs in Wasserdorf and fells the old lime in Ferry Lane. Report.
- 27 November 2015, Vellmar. A storm strips roofs in Vellmar and fells the old lime in Garrison Street. Report.
- 15 December 2015, Lindenmar. A storm strips roofs in Lindenmar and fells the old lime in Mill Gate. Report.
- 19 December 2015, Dammberg. The coldest night in 50 years is recorded at Dammberg. Lake Tarn freezes to the middle. Report.