March 2015

El Nino conditions continued to develop through March and into April. NOAA declared an ‘official’ El Nino, but the Bureau of Meteorology as of the time of writing (25 April) had not. The sea surface temperatures are indicative of a weak El Nino and the atmospheric part of the ENSO cycle has become more prominent unlike last year’s El Ninito.

Over land, the following areas were unusually warm: western North America, parts of central and southern America, large areas of Africa with the exception of the north west, the Arabian Peninsula, northwest Asia with Northern Europe and eastern Europe, east Asia and north east Australia. Northern Japan saw record March temperatures and South Korea has its 2nd warmest March on record. Unusually low temperatures were recorded in the northeast of North America.

Record temperatures were reported from Cape Town in South Africa where temperatures reached 42C.

A spell of warm weather in Sweden early in the month saw record temperatures for the time of year. A maximum temperature of +8.5C in Mora was the warmest since 1959. The highest temperature recorded was in Oskarshamn where temperatures reached 18.7C, the highest temperature recorded anywhere in Sweden so early in the season. Stockholm had temperatures of 15.8C, the highest for the first half of March since the mid-1700s when records began. Finland was also unusually warm in March.

There were reports of record temperatures on the Antarctic Peninsula, the most northerly part of the Antarctic continent.

Large area of ocean were also unusually warm. The horseshoe pattern of unusually warm SSTs persisted in the north Pacific, with record SSTs for the time of year along the west coast of North America. Large areas of the Atlantic (north and south) were unusually warm, most particularly in the west and far north, as were large areas of the Indian Ocean. The western Tropical Pacific also continued to be very warm (warmth in the region has been implicated in the extreme contrast of temperatures across the US over the past two winters). Unusually cold SSTs were observed west of Drake’s Passage (which separates South America and the ANtarctic Peninsula), to the south of Greenland and Iceland and in the central north Pacific (the cold eye around which, to mix a metaphor, the horseshoe of warmer waters is bent).

Temperatures averaged across the globe show that it was a warm March, maybe the warmest, though we cannot say for sure etc…

Patterns of precipitation (based on the GPCC first guess fields) were, as usual, more varied than patterns of temperature typically are. Areas experiencing above average precipitation totals were Mexico, south east Europe, large areas of India, western Australia, parts of Chile. Parts of eastern Spain saw very high rainfall totals with some stations reporting record totals for the month. Campile on Corsica in the Mediterranean was also very wet (406mm where the normal is 63mm). Dry areas included areas of the US (although there was a strip of wetter than average conditions crossing the country), France, western Russia, eastern Australia, Portugal, northern China.

There was flooding in Chile. Desert areas which typically receive very small amounts of rain, received several years rainfall in a short period of time. Floodlist has details. Around 26 people died in the floods (update). Argentina also saw some heavy rainfalls with a record 24 hour total of 31mm recorded at Chilecito on 25th. Some other stations had record monthly totals for March.

In Malawi, two months of heavy rain to the start of March caused flooding (this is not clear from the GPCC maps which show Malawi as relatively dry in February and March, but it is evident in CPC SPI). There was also flooding in Tanzania in early March. Angola was also affected by flooding.

In Australia, heat waves, which peaked on 19 and 20 March, affected the Northern Territory and Queensland. Daily temperature records for March were broken at a number of stations as were some monthly records. The Bureau of Meteorology published a special statement on the heat waves. Australia was generally dry in the east, but wet in the west. Severe Tropical Cyclone Olwyn contributed to the above average rainfall totals in the west.

It was quite snowy in an Italian village. Although the WMO does not recognise snowfall records, the 24hr snowfalls experienced in the village were very high.

Arctic sea ice confused people everywhere by reaching the record minimum annual maximum in March. In other words there has never been less ice at the time of the year when there’s most ice. And various other formulations which only compound the confusion…

Tropical storms
NW Pacific – Tropical Storm BAVI 11-18 MAR
Super Typhoon-5 MAYSAK 27 MAR-05 APR
SW Pacific – Cyclone-5 PAM 09-15 MAR
Cyclone-2 NATHAN 10-22 MAR
Tropical Storm REUBEN 21-22 MAR
SW Indian – Tropical Storm FIFTEEN 05-07 MAR
Tropical Storm HALIBA 08-10 MAR
Cyclone-2 OLWYN 11-13 MAR (Australian summary)
Cyclone-1 NATHAN 22-24 MAR (Australian summary)

Cyclone Pam, Vanuatu: ReliefWeb report.

Sundries:
USA
New Zealand March summary: warm overall. Some dry, some wet.
Russia.
France http://www.meteofrance.fr/actualites/24094705-un-mois-de-mars-sec-au-nord-plus-humide-au-sud
Norway: http://met.no/Klima/Varet_i_Norge/2015/filestore/2015-033.pdf
Austria: relatively mild and sunny with turbulent end
Met Eireann: http://www.met.ie/climate/MonthlyWeather/clim-2015-Mar.pdf