الجولة الإرشادية اليوم.

In Arabic, the verb to be is usually not stated in the present tense.

So:

• الجولة الإرشادية اليوم literally looks like the guided tour today
• but it means The guided tour is today

This is a very normal Arabic pattern called a nominal sentence.

If you wanted past or future, Arabic would usually use a form of كان:

• كانت الجولة الإرشادية أمس = The guided tour was yesterday
• ستكون الجولة الإرشادية غدًا = The guided tour will be tomorrow

Because الإرشادية is an adjective describing الجولة, and in Arabic adjectives usually agree with the noun in definiteness.

Here:

• الجولة = the tour
• الإرشادية = the guided / orientation-related

So together:

• الجولة الإرشادية = the guided tour

If the noun were indefinite, the adjective would also be indefinite:

• جولة إرشادية = a guided tour

This agreement is very important in Arabic.

Because الجولة is a feminine singular noun, and the adjective has to match it.

So:

• جولة is feminine
• therefore the adjective must also be feminine: إرشادية

This is standard Arabic adjective agreement:

• gender
• number
• definiteness
• case

all usually match between the noun and its adjective.

الإرشادية comes from إرشاد, which means guidance, direction, or instruction.

So إرشادي / إرشادية literally means something like:

• guidance-related
• instructional
• orienting

In this sentence, the most natural English meaning is guided or orientation-related, depending on context.

So الجولة الإرشادية is the standard kind of expression Arabic uses for guided tour.

اليوم means today, and here it functions as a time expression.

It tells you when the guided tour is happening.

In grammar terms, it is often treated as a ظرف زمان (an adverbial expression of time), and in a fully vowelled form it is usually:

• اليومَ

So the fully vowelled sentence would commonly be:

• الجولةُ الإرشاديةُ اليومَ

Even though the short vowels are normally not written, that is the underlying grammar.

It can be understood as a full sentence:

• الجولة الإرشادية = the guided tour
• اليوم = today

So the full meaning is:

• The guided tour is today

That said, Arabic also often uses short, compact wording in things like:

• schedules
• signs
• announcements
• headings

So depending on context, it could also feel a bit like a concise notice rather than a fully expanded sentence. But grammatically, it works as a complete sentence.

A common pronunciation in MSA is:

• al-jawla al-irshādiyya al-yawm

A few helpful notes:

• جولة is pronounced roughly jaw-la
• إرشادية is roughly ir-shaa-diy-ya
• اليوم is roughly al-yawm

Also:

• the ة at the end of جولة and إرشادية is usually pronounced like -a / -ah when pausing
• the الـ in اليوم is pronounced normally, because ي is a moon letter, not a sun letter

A standard fully vowelled version would be:

• الجولةُ الإرشاديةُ اليومَ

Why those endings?

• الجولةُ: nominative, because it is the subject/topic of the nominal sentence
• الإرشاديةُ: nominative too, because it is an adjective matching الجولة
• اليومَ: accusative as a time adverb (ظرف زمان)

In normal everyday Arabic writing, those short vowels are usually omitted.

Yes. Arabic word order is fairly flexible, especially with time expressions.

The version you have:

• الجولة الإرشادية اليوم

is natural and neutral.

You could also say:

• اليومَ الجولةُ الإرشاديةُ

This gives more emphasis to today, almost like:

• Today is the guided tour or
• As for today, it’s the guided tour

So changing the order can shift the emphasis, even if the basic meaning stays similar.