Lyth was out to the first ball of the match having hit 488 runs in the first three games.
Without Lyth the Magnificent to bail them out of trouble, Yorkshire’s top-six was more exposed.
Only Tom Kohler-Cadmore (42) made a score – his highest of the season – as the hosts staggered to 206 all out on a day when 19 overs were lost to rain, bad light and even hail.
Dom Bess – looking too low in the order at No 7 – continued his solid start to the season with the bat, which has been as valuable to Yorkshire as his spin bowling.
Bess top-scored with 56 from 95 balls with 10 fours, helping them to recover from 80-5 after the top-order failed to cope with challenging conditions against a workmanlike attack, the hosts just scraping a batting point.
Whether an unremarkable Northants side fares appreciably better is a separate issue and remains to be seen. They closed on 36-0, and Yorkshire will still hope to be too strong for them as they chase a third successive win despite first innings difficulties now in three of their opening four fixtures.
“It moved around all day,” said Kohler-Cadmore, who looked good after managing only 70 runs himself in six innings prior to this match.
“Credit to their bowlers; they kept hammering away and putting us under a lot of pressure, but I reckon we’re about par with 200. Obviously you always want more runs on the board, but I feel 200 is competitive if we can get it right with the ball. Hopefully early morning it does a little bit and we can get on a roll.”
After Northants won the toss in initially sunny weather, which soon gave way to overcast skies, Lyth was somewhat unfortunate to be dismissed by the former Yorkshire pace bowler Ben Sanderson.
He tried to leave a delivery that would have gone on to miss his off stump but the ball just flicked the top of the left pad and rebounded back into the wicket.
After the shock of that dismissal, which seemed to take everyone by surprise, including the Northants players, Kohler-Cadmore got his eye in by twice driving Tom Taylor to the offside boundary.
Will Fraine, making his first appearance of the season in place of the rested Joe Root, in the only change to the Yorkshire side that beat Sussex, had a few nervy moments early in his innings.
The ball went past the outside edge a few times and Fraine was dropped on two by Rob Keogh at second slip off Sanderson, a regulation opportunity to the fielder’s right, even though the chance was fast at around shoulder height.
Later in the over, Fraine looked perilously close to being lbw, while Kohler-Cadmore, having twice driven Sanderson back down the ground to the Kirkstall Lane end boundary, survived a similarly confident lbw appeal on 27 from the South African pace bowler Wayne Parnell, who produced a mixed bag but still finished with his team’s best figures of 5-64.
There was certainly enough to interest the bowlers (this is still April, after all), but Kohler-Cadmore and Fraine warmed to their task as they raised a fifty partnership in 13 overs.
Their stand had climbed to 66 when Fraine was lbw trying to whip a delivery from Gareth Berg through mid-wicket that perhaps did not get up as much as the batsman expected.
Four balls later, with half-an-hour still to lunch, the weather drove the players from the field, resulting in the loss of eight overs and a 2.06pm restart – 2.05pm was presumably not a funky enough time.
Only three balls were possible and then it rained again, keeping the teams off for another 45 minutes and claiming another 11 overs. When the action resumed, Yorkshire lost three wickets for four runs in 20 deliveries.
Gary Ballance fell to the 11th ball back when he edged Parnell to second slip, where Keogh was again unable to cling on although this time he managed to parry the ball up to first slip Ben Curran, who completed the catch.
Parnell struck again in his next over when Harry Brook was lbw for a second-ball duck trying to drive a full-length delivery, and then Kohler-Cadmore lost his off stump when trying to defend against Berg to end an innings that contained 77 balls and included six fours.
That left Yorkshire 80-5 and in familiar strife, but Bess and Jonny Tattersall added 57 before Tattersall edged Sanderson to third slip. Jordan Thompson was bowled round his legs by Parnell, who then had David Willey caught behind low to his left by Ricardo Vasconcelos, who was deputising as captain and wicketkeeper for Adam Rossington, who was ruled out of the game with a finger injury.
Bess pulled Berg to mid-wicket, and Parnell finished things off when Steve Patterson edged behind an expansive off-drive.
The sun reappeared, which was just as well as play did not finish until 7.05pm, but Yorkshire were unable to match its lustre with a wicket.
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