Climatic Conditions in the North East India

Climate:

The North Eastern region has distinct climate variations. The rapid changes in topography result in climate changes within short distance. Generally the daily temperature in the plains of Brahmaputra and the Barak Valley as well as in Tripura and in the western portion of Mizo Hills is about 150 C in January, whereas in other parts of the region, the temperature is between 100C to 150C. From April it rises and in July except the south-eastern portion of Mizo hills and Shillong, the mean temperature ranges from 250C to 27.50C. During October, daily mean temperature in the hilly areas ranges between 200C and 250C, whereas in Brahmaputra and Barak Valley, Tripura and the western portion of the Mizo hills it is above 250C. Further the lowest temperature is experienced below freezing point in the upper Himalayas in Arunachal Pradesh.

Assam:

The sub-tropical climate of Assam is characterised by high rainfall and high humidity and is worked by three dominant seasons, viz. winter (November to February), summer (March to May) and monsoon (June to October). Most of the rainfall in the state is received under the influence of the south-west monsoon between June and October.

The Brahmaputra valley represents three broad climatic regions, viz. eastern, western and middle. The mean annual rainfall (MAR) of eastern, western and middle regions are 245.2 mm, 1982.5 mm and 1527.4 mm respectively. The mean annual temperature (MAT) are 23.50C, 24.50C and 240C with nine months having 200C in eastern, western and middle regions respectively.

The MAR of Barak valley is 4103 mm and MAT 24.90 C which are higher than those of the Brahmaputra valley. In both Brahmaputra and Barak valley, the natural water availability exceeds the water need during the rainy and summer seasons. This renders the soil moist for seven to nine months and therefore, the climate of these regions qualify for udic moisture regime. During this period, the low-lying areas remain saturated and the ground water levels remain high. Such localised wet areas qualify for aguic moisture regimes.

Source : "Inventory of Viable Technologies Based On Resources Of North Eastern Region" prepared by Assam Productivity Council

Arunachal Pradesh:

Owing to rapid change in topographic and altitudinal aspects, the climatic conditions tend to change within short distances. The territory receives wide rainfall from May to early October; June, and July being the wettest month. The average annual rainfall is about 260 mm.

Source : "Inventory of Viable Technologies Based On Resources Of North Eastern Region" prepared by Assam Productivity Council

Manipur:

Manipur enjoys a sub-tropical monsoon climate. It belongs to the temperate rainy climate region with dry winter and hot summer. Average warmest temperature ranges between 250C and 310C. Rainfall is relatively abundant and widespread, varying from a maximum of 258.9 cm at Jiribam to only 97 cms at Wanghal. Period from December to February continues the cold season, March to May is the hot weather, the monsoon starts from May and lasts up to September and the season of retreat of monsoon is from September to November.

Source : "Inventory of Viable Technologies Based On Resources Of North Eastern Region" prepared by Assam Productivity Council

Meghalaya:

The climate of the state as a whole may be described as cold, chilly and frosty in the highest region which is the central plateau, mild and pleasant in the regions, where the central plateau meets the two border areas, but not moist and oppressive towards the border of Bangladesh and Assam. The mean maximum temperature is around 300C while the mean minimum temperature is around 120C at Shillong. The average relative humidity being 76%.

Practically the whole of the state is covered by the south-western monsoon which normally begins from the month of May and lasting up to the month of October. The southern border area of Jaintia Hills district of the state receives the highest amount of rainfall where the two wettest places in the world are situated viz. Cherrapunjee and Mawaynram. On the whole, the rainfall in the state can be described as heavy in comparison with many other states in the country.

Source : "Inventory of Viable Technologies Based On Resources Of North Eastern Region" prepared by Assam Productivity Council

Mizoram:

Mizoram enjoys a pleasant climate which is neither very hot nor very cold. The state has a moderate humidity too. In summer the temperature varies between 200C and 290C, while in winter it varies between 110C and 210C. In autumn (Sep to Oct) except for a few showers, heavy rains cease and the temperature is usually between 25.40C and 18.70C. In winter (Nov to Feb) the temperature is usually between 11.80C and 24.70C. There is little or no rain during winter. The entire territory is under the direct influence of monsoon. In the higher ridges it is fairly cool and pleasant even at the hottest season of the year.

Mizoram gets a substantial amount of rainfall each year. The average rainfall being 254 cm per annum. Owing to the steepness of the hillsides and the narrowness of the valleys, the rivers rise after heavy rain with wonderful rapidity.

Source : "Economic Development of Mizoram" by Lianzala

Nagaland:

Nearly the whole of Nagaland is situated in a hilly terrain. In the North, where Nagaland has a common border with Assam, the hills are lower in altitude and gradually taper down into the Brahmaputra plains. Towards the south and east, the hills are higher in altitude. Because of the altitude, temperature is low. In winter the mercury falls considerably although in the inhabited area, snowfalls are very rare. The climate is bracing and healthy. The summer high temperature ranges between 24.40C and 32.80C.

The annual rainfall occurring mostly between April and October averages between 681 mm and 924.6 mm.

Source : "Industrial Resource Survey of Nagaland" by Industrial Extension Services, Dimapur.

Tripura:

The climate is generally hot and humid with temperature ranging between 10.40C to 350C. The normal average rainfall in the state is 230 cms. Humidity becomes the maximum in June and minimum is recorded in April. Rainy season is from May to October.

Source : "Inventory of Viable Technologies Based On Resources Of North Eastern Region" prepared by Assam Productivity Council

Sikkim:

Cold Winters in the month of November to February with minimum temperatures dipping to 4 centigrade during January - February. It is between the month of March and early May when sunshine is quite abundant. Though summer is officially from May to October, Sikkim is almost always wet due to the heavy monsoons, with rains at times continuing for days on ends. Longest recorded nonstop rain is 11 days. September to October is Autumn. A peculiar feature of Sikkim weather is that though there is a classification of sorts of the various seasons, actually experiences a cold winter from end of November to February and monsoons throughout the year with a little respite during May - June and October - November. Even the winter months can be irritatingly wet and damp with the unpredictable showers.

Source :Sikkiminfo.net

Annual Rainfall:

(in full millimetre)

Source: Statistical Pocket Book India 2008