A jump overcall of 2NT shows at least 5–5 in the lower two unbid suits. (It may show 2=2=4=5 distribution but in that case it should be a king stronger.)
(1♦) - 2NT: hearts and clubs
The strength is either weak or very strong/distributional. (Any subsequent bid by the overcaller shows extra strength or distribution.) With an normal opening hand it is better to bid the higher suit then rebid the lower suit if needed.
Note: Unusual 2NT may be off in the reopening seat (see NT Overcalls above).