Difference between Presage and Portend

PRESAGE vs PORTEND: NOUN

A prediction.
Prophetic significance or meaning.
A feeling or intuition of what is going to occur; a presentiment.
An indication or warning of a future occurrence; an omen.
A foreboding about what is about to happen
Foreknowledge; prescience.
Something which foreshows, portends, or gives warning of a future event; a prognostic; an omen.
A foreboding; a presentiment; a feeling that something is to happen; a prophetic impression.
Prophetic significance or import.
Synonyms Sign, Augury, etc. See omen and foretell.
Something which foreshows or portends a future event; a prognostic; an omen; an augury.
Power to look the future, or the exercise of that power; foreknowledge; presentiment.
A warning of a future event; an omen.
An intuition of a future event; a presentiment.
A sign of something about to happen

To serve as an omen or a warning of; presage.
To indicate by prediction; forecast.
To indicate (events, misfortunes, etc.) as in future; to foreshow; to foretoken; to bode; -- now used esp. of unpropitious signs.
To stretch out before.

To have a presentiment of the future; have foreknowledge.
=Syn. 3. Predict, Prophesy, etc. See foretell.
To point out.
To foretell; predict; calculate beforehand.
To have a presentiment or prophetic impression of; forebode.
To foreshow or foretoken; signify beforehand, as by an omen or prognostic; give warning of.
Indicate, as with a sign or an omen

Herald, Auspicate, Prognostic, Forecast, Prognosticate, Predict, Omen, Betoken, Portent, Bode, Augur, Prefigure, Foretell, Foreshadow, Portend

Loom, Signify, Foresee, Auspicate, Forecast, Prognosticate, Betoken, Predict, Omen, Prefigure, Augur, Bode, Foretell, Presage, Foreshadow

Imminent, Precede, Foresee, Foreboding, Herald, Auspicate, Prognostic, Forecast, Prognosticate, Omen, Betoken, Augur, Prefigure, Foreshadow, Portend

Materialize, Bespeak, Precede, Allude, Forestall, Foresee, Auspicate, Forecast, Prognosticate, Betoken, Omen, Prefigure, Augur, Presage, Foreshadow

But the code modifications likely presage more significant design and function improvements to come.
Presage exploits redundant information embedded in natural languages to generate word predictions.
However, these signs of volcanic unrest do not always presage an eruption.
History of giftedness: Perspectives from the past presage modern scholarship.
Is not this a direful presage of farther Wrath?
Then seek this path that I to thee presage.
Full list of synonyms for Presage is here.
US Treasury yields presage a jump in inflation.
It might also presage his defeat in battle.
Its three components are presage, process, and product.