Global Precipitation & Temperature Outlook for February 2018

5 February 2018

OVERVIEW
Much warmer than normal temperatures are forecast in February for the US West, the Baja Peninsula, the Tibetan Plateau, and far northeastern Russia. Nearly all of India will be warmer than normal. Paraguay is expected to be cooler than normal. Eastern Brazil should see above average rainfall, as will central Mexico and western India.

PRECIPITATION OUTLOOK
We'll begin this month's catalog of precipitation anomalies in South America, where our model indicates more activity than most other parts of the world. Eastern Brazil is forecast to be wetter than normal with moderate to extreme anomalies and some pockets of exceptional severity. Primarily moderate wet anomalies are expected in northern Paraguay, trailing northwest through central Bolivia. The northern border of Chile and Argentina may be much wetter than normal.

Much drier than normal conditions - a return period of 40 or more years - are forecast for northern Peru and into Ecuador. Moderate to exceptional dry anomalies are forecast for Brazil's southern states and along South America's northeastern coast through Guyana, Suriname, and French Guiana. Primarily moderate dry anomalies are expected in southern Colombia, Venezuela, southern Peru, northern Argentina, and Uruguay.

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… — 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.

Moving north, wetter than normal conditions are in the forecast for central Mexico and may reach extreme or even exceptional intensity along the southwestern coast and near Mexico City. Moderate wet anomalies are forecast for eastern Yucatán, southern Guatemala, and El Salvador.

In the US, conditions are expected to be drier than normal in northern California, Oregon, and into Nevada and Idaho, and may be severe. A block of moderate to severe dry anomalies is forecast for New Mexico. A wide path of moderate to severe wet anomalies is forecast from western Montana well into Canada. Northern Ontario is expected to be moderately drier than normal, and Newfoundland will be wetter than normal.

Wetter than normal conditions are forecast across northern Africa from Algeria through northern Egypt. The following regions are also expected to be wetter: Senegal, southern Nigeria, Cameroon, eastern Ethiopia, northern Somalia, Botswana, and northeastern South Africa. Moderate to exceptional dry anomalies are forecast for Tanzania, Uganda, Rwanda, Burundi, and southeastern Democratic Republic of the Congo.

The forecast indicates wetter conditions in Maharashtra and surrounding areas of western India. India's far northeast and eastern Myanmar will see moderately wetter conditions. Primarily moderate dry anomalies are forecast in pockets of southeast Asia, mainland Malaysia, and Sumatra.

TEMPERATURE OUTLOOK
A large, nasty red block blanketing the US West and down the Baja Peninsula immediately draws our attention in February's temperature forecast. Temperatures hotter than what would normally be seen in 40 or more years are projected for this region. Severe warm anomalies are expected in the Pacific Northwest and much farther north in western Alaska. Moderate warm anomalies in Texas will grow more severe as they reach deep into northern Mexico, and temperatures may be exceptionally hotter than normal in a pocket near Puerto Vallarta.

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… — 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.

In South America, deep blues in the center of the continent indicate a forecast of much cooler than normal temperatures in Paraguay reaching into Matto Grosso do Sul and Paraná, Brazil, and also into Argentina and Bolivia. Much of Peru is expected to be warmer than normal with a return period of 20 to 40 years. Warm anomalies will reach well into central Brazil and southern Colombia, and are also expected in Guyana, Suriname, French Guiana, Amapá (Brazil), and along Brazil's easternmost coast. Much warmer than normal temperatures are forecast in Nequen and La Pampa Provinces in central Argentina, dissipating into anomalies of lesser severity throughout much of the southern half of the country. Severe warm anomalies are forecast near Santiago, Chile.

In Africa, conditions are expected to be much cooler than normal in Morocco reaching into northern Algeria. Primarily moderately cooler than normal temperatures are forecast for the southern Iberian Peninsula, Western Sahara, and Mauritania. Warm anomalies with a return period of 10 to 40 years are forecast for Egypt and for Nigeria's northern half, and moderate to severe warm anomalies are expected in eastern Niger, Chad, and Sudan. Warmer than normal conditions are also forecast in pockets around the Gulf of Guinea, in central Africa, the Horn of Africa, and in northern Madagascar. Southern and eastern South Africa will see moderately warmer than normal temperatures.

Romania and Bulgaria will be somewhat warmer than normal, as will the eastern Mediterranean, with more intense conditions in eastern Turkey.

Moderate to severe warm anomalies are forecast for Tajikistan, and into northern Afghanistan and Pakistan. Moderate warm anomalies are expected from eastern Kazakhstan across much of northern China through Inner Mongolia, and in central Russia and western Mongolia. Exceptionally warmer than normal temperatures are forecast for a vast extent of northeastern Russia, including the Kamchatka Peninsula.

Nearly all of India is forecast to be warmer than normal, and conditions may be exceptional in eastern Gujarat, northern Karnataka, and Odisha. The Tibetan Plateau will be exceptionally warmer than normal. Warm anomalies of varying severity are forecast for Bangladesh, western Myanmar, Malaysia, Indonesia, and Papua.

Northeastern Queensland, Australia will be moderately warmer than normal but farther south near Brisbane, warm anomalies may be extreme.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

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 February 2, 2018 which includes forecasts for February 2018 through October 2018 based on NOAA CFSv2 forecasts issued January 25 through January 31, 2018.

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.