Ether price volatility could spike in the days ahead, courtesy of an upcoming ethereum upgrade scheduled for Thursday.

The Constantinople hard fork, a planned two-part upgrade to the world's second-largest cryptocurrency, is scheduled to occur once block 7,280,000 on the ethereum blockchain is mined. At the time of writing, ether’s block height is 7,272,826, meaning the fork should occur in the next 24 to 48 hours, given that roughly 4,200 blocks have been mined per day for the past two weeks.

However, the change could draw the interest of more than just developers and users, as historical data shows ether price volatility tends to spike hours before a software upgrade.

For instance, ether price volatility picked up with the Byzantium hard fork release on Oct. 16, 2017, with the resulting uncertainty forcing traders to sell ETH and unwind their long positions leading to a 20 percent price slide.

As shown in the chart above, traders on that date were unwilling to invest amid a change to the underlying ethereum protocol.

The Chaikin Money Flow (CMF), used to gauge momentum as well as buying and selling pressure, demonstrated a break into bullish territory (a move above 0) on Nov. 14, 2017 after a brief visit below when prices went through a 20-day consolidation period.

Overall, it took a total of 34 days for ether’s price to break above the sideways channel after the fork occurred, so if history repeats itself, ether prices may be destined for a multi-week sideways trend after the Constantinople upgrade takes place.

Still, it's also worth noting current trading conditions and the overall bear market for cryptocurrencies at present.

ETH/USD witnessed a considerable sell-off Sunday when its price dropped 17 percent after having clocked a three-month high earlier in the day. The CMF on the daily time frame was still printing a value above zero, so a bearish view is not yet confirmed as per the indicator.

However, if bears continue to drag price lower, the sell-off would likely be short and fast unless the amount of selling volume increases substantially, in which case it would add credence to the fall and put the price at risk of falling below the prior support level $123.

If the Constantinople fork aftermath resembles that of what transpired in ether markets following the Byzantium fork, ether prices should not exceed a drop beyond 20 percent. It's also possible that delays in the scheduled update could impact the market, and traders may want to be prepared accordingly. 

The Constantinople hard fork was delayed in January of this year due to unforeseen mistakes during testing, a move that caused a slight drop in the ether price, as reported by MarketWatch at the time.

Disclosure: The author holds no cryptocurrency at the time of writing.

Ether Fork Image via Shutterstock; Charts by TradingView