Learn Hardcore Turkish: Herhalde bugün yağmur yağacak; şemsiyeyi hazır tutalım. - I suppose it will rain today; let’s keep the umbrella ready.

It primarily means "probably / I suppose," expressing a guess based on signs or common sense.
Tone matters: it can sound mildly hedging or tentative.
In some contexts it can be ironic ("surely, I guess you…"), but here it’s a neutral hedge.
Near-synonyms: galiba (colloquial), muhtemelen (more formal), sanırım (more personal: "I think").

Is it Herhalde or her halde? Are both correct?

Herhalde (one word) = "probably." That’s what you want here.
Her halde (two words) literally "in every condition/state" and is rare/specialized. Don’t use it for "probably."

Why do we say Yağmur yağacak? Isn’t that redundant?

Can I drop yağmur and just say Bugün yağacak?

It’s grammatical and often understood from context (especially in weather talk), but it’s vaguer: it could mean rain, snow, etc.
To be explicit, keep yağmur, or say alternatives like Bugün yağmur bekleniyor / Bugün yağmur var.

Why is it yağacak and not yecek/ecek? How does the future suffix work?

The future is -(y)ecek / -(y)acak with 2-way vowel harmony:
- After front vowels (e, i, ö, ü): -ecek (e.g., gelecek).
- After back vowels (a, ı, o, u): -acak (e.g., yapacak, yağacak).
Yağ- has a back vowel (a), so you get yağacak.

What’s the difference between yağmur yağacak and yağmur yağar?

Yağmur yağacak: a concrete prediction about the (near) future; sounds more definite in conversation.
Yağmur yağar (aorist): habitual/generic truth ("it rains [there]") or a neutral forecast style sometimes used in weather reports.
Both can refer to the future, but -acak feels more like "it’s going to."

How do I pronounce ğ in yağacak and yağmur?

Ğ isn’t a hard "g." It lengthens/smooths the preceding vowel.
In yağacak, the "a" is lengthened; the ğ itself is barely audible.
In yağmur, the first vowel is lengthened; you may hear a slight glide, but not a hard consonant.

Why is şemsiyeyi in the accusative? Could I just say şemsiye?

Şemsiyeyi (accusative) marks a specific/definite object: "the umbrella (we have in mind)."
Without accusative, it sounds indefinite/general. The natural indefinite version is Bir şemsiye hazır tutalım ("let’s keep an umbrella ready").
Bare Şemsiye hazır tutalım is unusual; add bir or use the accusative for clarity.

What is the extra y in şemsiyeyi?

It’s a buffer consonant inserted when a vowel-final word takes a vowel-initial suffix.
Structure: şemsiye + (y)i → şemsiyeyi.
This prevents a vowel clash and is very common (e.g., araba + (y)ı → arabayı).

What does hazır tutalım mean grammatically?

Hazır ("ready") is used adverbially with tutmak ("to keep/hold") to form "keep [something] ready."
Tutalım is the 1st person plural optative/imperative: -alım/-elim = "let’s [do]."
So hazır tutalım = "let’s keep [it] ready."

Could I say şemsiyeyi hazırda tutalım or şemsiyeyi hazır bulunduralım?

Yes:
- Hazırda tutmak: "keep at the ready."
- Hazır bulundurmak: "keep available/on hand" (a bit more formal).
Another natural option: Şemsiyeyi yanımızda bulunduralım ("let’s carry the umbrella with us").

Why is the word order şemsiyeyi hazır tutalım and not hazır şemsiyeyi tutalım?

Turkish prefers SOV order; the object (şemsiyeyi) typically precedes the verb.
Hazır modifies the verb phrase ("keep ready"), not the noun ("ready umbrella"), so hazır şemsiye would be odd here.
You can move the object for emphasis: Hazır tutalım şemsiyeyi, but the given order is neutral.

Is the semicolon necessary? Could I use a comma or a period?

All three are possible:
- Semicolon (as written) ties two closely related independent clauses.
- Comma is also common in Turkish for linked clauses.
- A period makes two separate sentences: … yağacak. Şemsiyeyi …
Meaning doesn’t change; it’s about pacing and emphasis.

Where can I place herhalde and bugün?

Both Herhalde bugün yağmur yağacak and Bugün herhalde yağmur yağacak are natural.
Fronted items gain slight emphasis: starting with Bugün highlights the time; starting with Herhalde highlights the tentativeness.

How do I turn the suggestion into a question like "Shall we keep it ready?"