Global Precipitation & Temperature Outlook for January 2017

Global Precipitation & Temperature Outlook for January 2017

3 January 2017

Overview
The January 2017 Outlook indicates a forecast of considerably wetter conditions in northern South America, southern Africa, and Southeast Asia. Much warmer than normal conditions are forecast for China, Indonesia, South Asia, West Africa, Mexico, eastern Brazil, and Greenland.

Precipitation Outlook
The large yellow/orange/red area in eastern Brazil on the precipitation map below indicates a forecast of moderate to extreme dry anomalies. On the other side of the world, dry anomalies of comparable intensity but lesser extent light up eastern Tibet.

Primarily moderate dry anomalies are forecast for: northern Canada; western Texas; Sinaloa, Mexico; western Ecuador into Peru; northern Finland; western Saudi Arabia; western and northeast China; the Ganges Basin and Assam, India; northern Myanmar; and southern Japan.

Precipitation outlook. Reds indicate below normal monthly total precipitation. Blues indicate above normal monthly total precipitation. The darker the color, the more extreme the anomaly relative to a 1950-2009 climatic baseline. Colors are based on the expected return period of the anomalies.

Blues and greens draw our attention to regions where wetter than normal conditions are expected. Exceptional wet anomalies - greater than 40 years expected frequency - (shown in dark blue) are forecast in southern Venezuela; eastern Amazonas, Brazil; eastern Myanmar; and southern Yunnan, China. 

Wet anomalies ranging from moderate to exceptional are forecast across northern South America, including: northeastern Peru; eastern Ecuador; western and eastern Colombia; Venezuela's eastern two-thirds; Guyana; Suriname; French Guiana; and northwestern Brazil. Moderate to severe wet anomalies are forecast for Rio Grande do Sul in southern Brazil, and Uruguay into Argentina.

A block of moderate to severe wet anomalies is noticeable in southern Africa, and includes southeast Angola, western Zambia, Namibia, Botswana, Zimbabwe, western South Africa, and western Mozambique.

Wet anomalies ranging from moderate to exceptional are forecast from Yunnan, China through eastern Myanmar, Thailand, Laos, Cambodia, and Vietnam, with greatest intensity - as previously mentioned - in Yunnan and Myanmar.

Wet anomalies of varying intensity are also forecast in: the US Deep South; Southern California, Nevada, Utah, and Colorado; northern Alaska; western Greenland; far eastern Russia; and northern Australia.

Temperature Outlook
Though normal temperature conditions are forecast for parts of the world - as shown in white on the map below - vast expanses of bright orange and red indicate much warmer than normal temperatures are expected during January for many highly populated regions.

Temperature outlook. Reds indicate above normal monthly average temperature. Blues indicate below normal monthly average temperature. The darker the color, the more extreme the anomaly relative to a 1950-2009 climatic baseline. Colors are based on the expected return period of the anomalies.

Most noticeable is the expanse of severe to exceptional heat anomalies across China. Anomalies of comparable intensity are also forecast for Myanmar, northern Laos, western Thailand, and Indonesia. Moderate to severe heat anomalies are forecast across southern Australia.

Exceptionally warmer temperatures are expected in southern and northeastern India; with anomalies ranging from moderate to extreme for the remainder of the country as well as in Pakistan, Afghanistan, and Iran.

In Africa, severe to exceptional anomalies trace a broad path from West Africa around the Gulf of Guinea. Anomalies of slightly lesser intensity are forecast for South Africa and the Horn of Africa. In contrast, cooler than normal temperatures are forecast for Botswana and neighboring areas of Zambia, Angola, and Namibia. Southeastern Ethiopia is also expected to be cooler.

In South America, severe to exceptionally warmer conditions are forecast for a vast area of eastern Brazil, while central Venezuela is forecast to be cooler than normal.

Exceptional heat anomalies are forecast for southern Mexico, particularly the Yucatan; warm anomalies ranging from severe to exceptional are expected in much of the remainder of the country and into Belize and Guatemala. Cuba and Jamaica are also forecast to be much warmer than normal.

Primarily moderate heat anomalies are forecast for the southern and southwestern US, but anomalies of greater intensity are forecast for Florida.

Temperatures across Greenland are expected to be abnormally high. 

About This Blog Post
Each week, ISciences processes an ensemble of 28 seasonal temperature and precipitation forecasts issued by the National Oceanic and Atmospheric Administration's Climate Forecast System Version 2 (CFSv2). We present our results in a proprietary weekly report titled Global Water Monitor and Forecast: Precipitation and Temperature Outlook. This blog post summarizes our Outlook released January 3, 2017 which includes forecasts for January 2017 through September 2017 based on NOAA CFSv2 forecasts issued December 25 through December 31, 2016.

Technical details:

  • Each CFSv2 forecast is bias corrected by:
    • Constructing probability density functions from CFSv2 hindcasts.
    • Fitting the hindcast probability distribution functions to a generalized extreme value distribution.
    • Using an inverse lookup to an extreme value distribution fitted to the observed temperature and precipitation record (Fan & van den Dool 2008, Chen et al. 2002).
  • The map colors depict the return period of the median forecast anomaly.
  • Regions where the interquartile range of the ensemble spans both above normal and below normal conditions are hashed as having uncertain direction.
  • Regions where the interquartile range of the ensemble divided by the median forecast is large (>0.4) are hashed as having uncertain magnitude.
  • Results are reported in terms of return period using a 1950-2009 baseline.