Momijiba wa yowa no shigure ni araji kashi kinō yamabe o mitaramashikaba - Izumi Shikibu Nikki(English Translation & Meaning)

紅葉はゝ夜はの時雨にあらしかし
昨日山へをみたらましかは

Roma-ji: Momijiba wa yowa no shigure ni araji kashi kinō yamabe o mitaramashikaba
English Translation: The crimson leaves, surely,
are gone in the showers of the night;
not one remains, I think—
if only yesterday we'd gone
to see the mountainside
Meaning: Surely not a single crimson leaf is left after the night's showers. If only we had gone to see the mountainside yesterday.
Commentary: 32 The Promise to View Autumn Leaves

On the evening of their exchange on the frosty morning, the prince came and invited her: "How lovely the autumn leaves on the mountains must be now. Come, let us go and see them," and Izumi Shikibu replied, "That would be delightful." But when the day came, the prince sent word: "Today I must stay shut in for a day of abstinence, which is a great pity. Once it is over, without fail." That night the winter showers fell harder than usual, with a sound as though every leaf on the trees would be stripped away. Waking, Izumi Shikibu murmured to herself, "before the wind," and spent the rest of the night regretting that the leaves must all have fallen and wishing they had gone to see them the day before.
The woman is Izumi Shikibu, daughter of Ōe no Masamune and, as the wife of Tachibana no Michisada, Governor of Izumi, mother of Koshikibu no Naishi. The Prince of the Dazaifu is Prince Atsumichi, fourth son of Emperor Reizei, so called because he served as Governor-General of the Dazaifu. A day of abstinence was a period of staying shut indoors and keeping oneself pure in order to avoid misfortune, according to the art of yin and yang.
Following her reply to the prince, "Shigure ka mo nani ni nuretaru tamoto zo to sadamekanete zo ware mo nagamuru," Izumi Shikibu added this poem with the words "And by the way," lamenting that the leaves must all have been stripped by the showers she had listened to all night.
Reading it, the prince replied with "Soyo ya soyo nado te yamabe o mizariken kesa wa kuyuredo nan no kai nashi," and in the margin added "Arashi to wa omou mono kara momijiba no chiri ya nokoreru isa tazune min."

The first three lines mean "surely the leaves will not have survived the midnight showers," with a negative conjecture and a particle of emphasis.
The lower verses mean "if only we had seen the mountainside yesterday," a counterfactual construction after which "it would have been better" is left unspoken. Rather than reproach the prince for postponing their promise because of his abstinence, she laments that they did not go yesterday, conveying her disappointment at the broken promise.
Author: Izumi Shikibu
Source: Izumi Shikibu Nikki
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