Just 70 minutes play was possible as the County welcomed back crowds to Wantage Road to watch Lancashire advance to 59 without loss from 16.5 overs in the morning session.
Northants captain Adam Rossington had won the toss and opted to give his seamers first use of a pitch in overcast and windy conditions.
Gareth Berg and Ben Sanderson beat the bat regularly and saw a number of edges fly just wide of the slip cordon.
The Lancashire pair though looked to be positive, with Davies striking three fours and bringing up the 50 stand when he clipped Tom Taylor through midwicket.
Jennings then found the boundary by going down one knee to stroke Parnell through the covers before surviving a big shout for leg before wicket against the same bowler on 20.
The rain then forced the players from the field.
A planned resumption after lunch had to be abandoned when the bad weather returned and play was eventually called off shortly after 4pm.