March 2023 Global Soil Moisture Observations and Outlook

Highlight: Expecting drought erosion in the Central U.S. and France for meteorological spring. East of Black Sea dryness strengthens. Brazil turns wetter and Australia drier. Dryness Northeast India to China.

Fig. 1: February 2023 global soil moisture anomalies and 3-month trend.

Observation discussion: A wet 3-month period shifted soil moisture much wetter from California to the Upper Midwest U.S. (Fig. 1). Wisconsin observed their wettest winter on record while most states from California to the Upper Midwest U.S. were at least top 10 wettest and may top 5 wettest. The Mid-south and New England region were also wetter during the past 3 months. The catalyst to the wetter winter soil moisture changes was an active Pacific storm track. In South America, presence of marine heat waves east of Argentina and evolving off the Chile Coast inspired strong subtropical high-pressure ridging which accelerated the Argentina and Chile drought areas. To compensate for the high-pressure ridge, an upper low formed over Paraguay to soak that region. A drier trend emerged over the winter season to cause France to slip back into drought. The drier trend extends southwestward into Interior Northwest Africa. South Arica drought was fading during the past 3 months while dryness for East Africa strengthened. Turkey was generally somewhat drier during the past 3 months while either side of the Caspian Sea was also trending drier. Western to Central Russia observed a wetter trend. Northeast India northeastward to Southwest China was notably drier as drought concerns increase in this zone. Western Indonesia turned drier. South Korea and southern Japan soil moisture conditions turned somewhat drier heading into March. Finally, Southwest and the Central Coast of Australia observed a drier soil moisture regime.

Fig. 2: February 2023 global soil moisture anomalies and 3-month forecast.

Forecast discussion: During MAR/APR/MAY 2023 a drier regime re-emerges across the Southwest U.S. and Northern Mexico as high pressure becomes established in this region (Fig. 2). However, northeastward of the high pressure zone, a springtime upper trough brings above normal rainfall to erode Central U.S. drought and maintain an East-central U.S. wetter trend. Brazil is likely wetter during the next 3 months while the Argentina Drought may extend to Southeast Brazil. South-central Europe dryness strengthens during meteorological spring while the drought pattern in France is expected to ease. West tropical and Interior South Africa are wetter. The drought in Turkey may ease while dry soil conditions east of Black Sea accelerate. Dryness is likely to strengthen in Northeast India and East China the next 3 months while Vietnam and Northern Indonesia are wetter. Western Indonesia and much of Southern Australia trend drier.