Weather: If you are feeling unusually colder these days it’s because the temperature across the country has gone slightly below normal due to the westerly cold dry air blowing over the last few weeks.
The normal temperature is the average minimum temperature calculated from 1996 to 2014 by the Meteorology division in Thimphu.
However, as per the forecast from the meteorology division, starting this weekend, one can expect to feel slightly warmer because the temperature is going to rise from 2 to 3 °C across the country. This means there will be no snow in Thimphu for a while.
Senior Meteorologist with meteorology division, Tayba Buddha Tamang, said there is no forecast of precipitation or snow for next four to five days. “It will be dry and cold during mornings, but temperature is expected to rise from this weekend.”
The snowfall in Gedu last week was a localised convective precipitation, added Tayba Buddha Tamang. “During that time, the temperature was lower than freezing point and there was precipitation. Similar low temperatures were observed in the past years in 1998, 2006, 2010 and this year.”
This phenomenon cannot be concluded directly to climate change, but it happens mostly due to the inter-annual climate variability such as the El Nino Southern Oscillation (ENSO) event, which is also active during certain period.
ENSO is caused by variations in sea surface temperatures over the tropical eastern Pacific Ocean that affects much of the tropics and subtropics.
Thimphu received considerable amount of snowfall last year, particularly in Dochula, Kuenselphodrang, Motithang and Dechenphodrang.
For snow to fall, precipitation has to occur and the air temperature should be below 2 °C. Snow is formed when temperature is low and there is moisture in the form of tiny ice crystals in the atmosphere.
“When these tiny ice crystals collide they stick together in the clouds to become snowflakes. If enough ice crystals stick together, they’ll become heavy enough to fall to the ground,” Tayba Buddha Tamang said.
Bhutan being a small and mountainous country, it is very challenging to provide weather and climate forecast due to the micro weather and climate variation within mountain areas.
The lowest temperature recorded in the country was -6 °C on December 19 this year. The lowest temperature ever recorded was –6.4 °C on December 21 and December 23 in 1998.
According to the Simtokha Meteorology Station, the lowest temperature recorded so far was at -8.5 °C on the morning of January 13 in 2005.