The Danube delta moderated a continental climate with pontischen influences. The broad water surfaces are covered, by different plant types and by sand-thin and reed islands are defined. Thus they form an active range particularly in delta and in neighbouring lagoons however totally differently to those, which belong to the Ponti steppes.

This will receive by the influence of the solar radiation, which is intercepted by the general circulation of the atmosphere, and a mosaic of mikroklimas results in. The solar radiation varies from a minimum of 3.5 kcal/cm² in the winter and a maximum of 17 kcal/cm² in July. In agreement with the intensity of the barometric activity, specific weather conditions are agreed upon: mild winter days (if northeast Central European wind influences), icy winter days, with heavy hoists (if the north Atlanticantizyklone occurs), warm and dry summer days (if occur the tropical-Atlantic anticyclone), rainy summer days (if air in the Mediterranean basin on the cool air in the northwest of Europe influences). The daily duration is long, which amounts to average of several years 2250 hours and it can reach 2600 hours in the years with reduced foggyness.

The temperature is not distributed evenly on the range of the Deltas. The averages of several years indicate temperature increases from the west to the east. At the top side of the Deltas (Tulcea), the annual average temperature 10,94 amounts to °C, in the fluvialen delta, with Gorgova amounts to it 10,96 °C, at the coast (Sulina) amounts to it 11, 05 °C, and on the high seas of the black sea (the Gloria platform) it amounts to 11,86 °C. The daily maximum averages show the main differences because of the nature of the active zones: with Gorgova it varies from a maximum of 9 °C (in July) to a minimum of 3.8 °C (in December), with Sulina, of 2.8 °C (in July) and 1,4 °C (in November) and at the Gloria station of 2.3 °C (in July) and 1°C (in December and February).

The annual sum total of the daily actual average temperatures are nearly 1600°C. The air humidity registers the highest values on the Romanian area. The relative air humidity varies in winters of 88 on 84% with Gorgova and of 89 to 85 % with Sulina and Sf. Gheorghe and in the summer, from 69 to 71 % with Gorgova and from 77 to 80 % with Sulina and Sf. Gheorghe. Precipitation is reduced in the quantity and them to reduce itself from the north to the south special of the delta after the black sea. At the front of the Donaudeltas (Tulcea) an average amount of precipitation of several years is registered of 450 millimeters, and with Sulina, the registered quantity amounts to 360 millimeters.

In most areas of the Deltas the precipitation quantity of the 350-400 millimeters amounts to, and on the deltaischen beach and most lagoons, the quantity lies below 350 millimeters. The snow layer is thin and does not last not long time, excluded the period of the severe winter. This happened in 1928-1929, 1953-1954, 1941-1942, 1984-1985, as the sea for 45-60 days to the coast einfrohr. The dominating wind direction comes from the north however alternates with the southern and largest wind accelerations, in the winter and in the transition seasons is registered. Seasons are not distributed evenly into the Danube delta. At the front of the Deltas, in Tulcea, the averages uncover for 90 years, 142 summer days and only 15 winter days, springs are longer (122 days) than Herbste (83 days).