Crude futures shot up on Friday on forecasts for falling U.S. temperatures, a weaker dollar and concerns the Ukraine ceasefire could crumble. A weaker greenback makes oil a more attractive commodity on dollar-denominated exchanges, especially in the eyes of investors holding other currencies. In the New York Mercantile Exchange, West Texas Intermediate crude oil futures for delivery in December traded up 1.05% at $78.73 a barrel during U.S. trading, up from a session low of $77.47 a barrel and off a high of $79.40 a barrel. The December contract settled down 0.98% at $77.91 a barrel on Thursday. Support for the commodity was seen at $75.84 a barrel, Tuesday’s low, and resistance at $80.98 a barrel, Monday’s high. Milder weather patterns across the central and eastern U.S. will soon give way to more winter-like weather in the coming days, which should drive demand for heating oil, a crude derivative. Elsewhere, a lackluster October jobs report weakened the dollar and gave crude futures even more room to rise. The Department of Labor reported earlier that the U.S. economy added 214,000 jobs in October, missing expectations for an increase of 231,000. The number of jobs added in September was revised to 256,000 from a previously estimated 248,000. The report also revealed that the U.S. unemployment rate ticked down to 5.8% in October from 5.9% in September. Analysts had expected the unemployment rate to remain unchanged last month. While not overwhelmingly disappointing, the less-than-stellar report gave investors room to sell the greenback for profits and take time to rethink when the Federal Reserve will hike interest rates next year. Geopolitical concerns pressured oil prices higher was well. The Ukrainian military accused Russia of moving 32 tanks and trucks carrying troops across its border, which spooked investors on concerns a ceasefire between the two countries could end. Fighting could potentially disrupt the flow of oil from energy-rich Russia. Separately, on the ICE Futures Exchange in London, Brent oil futures for December delivery were up 0.63% at US$83.39 a barrel, while the spread between Brent and U.S. crude contracts stood at $4.66.