〜から〜にかけて details
Examples
from A through B — the two ends of one stretch, with the event occurring somewhere across it rather than filling it
今夜から明日の朝にかけて、強い雨が降るでしょう。
kon'ya kara asu no asa ni kakete, tsuyoi ame ga furu deshou.
Heavy rain is expected from tonight through tomorrow morning. neutral
六月から七月にかけて、この辺はあじさいがきれいだよ。
rokugatsu kara shichigatsu ni kakete, kono hen wa ajisai ga kirei da yo.
From June into July the hydrangeas around here are lovely. casual
関東地方から東北地方にかけての広い範囲で、強い揺れを観測しました。
kantou chihou kara touhoku chihou ni kakete no hiroi han'i de, tsuyoi yure o kansoku shimashita.
Strong shaking was recorded across a wide area from Kanto through Tohoku. formal
Formation
AからBにかけて（春から夏にかけて・関東から東北にかけて）attaches to noun phrase (schematic)
Notes
cannot run backwards — ×五十代から二十代にかけて —
though a cycling one wraps freely (十二月から一月に
かけて). Either end may name a region rather than a point.
Related patterns
Similar
にわたって asserts the extent is covered in full and takes a single span noun, so it needs no second term (三年にわたって続いた); から〜にかけて names both ends and leaves the middle deliberately vague, which is exactly why forecasts and reports prefer it.
Lookalikes
から〜まで claims the whole interval is filled and takes one continuous activity (九時から五時まで働く); から〜にかけて names a rough region and says only that the event happens somewhere across it, by degrees or on and off — which is why ×九時から五時にかけて働く fails where 今夜から明日にかけて雪が降る does not.
Same にかけて, and the は is what changes everything — with から in front it marks a stretch (夏から秋にかけて), with は after it singles out the one field a person is unbeatable in (料理にかけては); neither reading survives the other's frame.