The phrase "from December onward" is correct and usable in written English.
It can be used to indicate a time frame starting with the month of December. Example sentence: All orders from December onward will be delivered with priority shipping.
From December onward, salaries are in arrears.
"Unless we take measures, we will not be able to pay the cash subsidies from December onward," Gholam Reza Tajgardoun, a former vice president, warned in the reformist newspaper Shargh Daily.
From December onward, production moved to Zurich, Switzerland, where locations were established at Dolder Grand Hotel and the Zurich Airport.
Available from June onward.
The autumn of 1966 was endlessly wet – from September onward the rains barely stopped.
Andrea Williams, managing director of Ambition, a headhunting firm in Hong Kong, said that things started to turn noticeably from April onward.
In February 2009, oil imports fell to their lowest level in more than three years before rebounding from March onward, as the economy regained momentum.
But in a series of e-mail messages from February onward, and in a public lecture at Harvard last month, Eric Lander, one of the three principal members of the consortium, has derided the shotgun method championed by J. Craig Venter, Celera's president.
If his boss were to make an observation about how Jon tries to keep his hard-working life in balance, that boss might note the number, diversity, and length of conversations about college basketball that occur around Jon's desk from November onward each year.
From September onward, the ITCZ begins to retreat southward, followed by a rainy period from mid-October to December over Kenya.
One noteworthy feature of the boreal monsoon circulation is the East African low-level jet (EALLJ), which develops from May onward in the southeast trade winds over Madagascar.
