bil jabal - للهجة الشامية

I'll add a couple of corrections to those made by Linolenic (mine are in red and bold dark blue):

bil jabal - للهجة الشامية

HayAl el aiam 3m bissir fi ghuyuum aktar w aktar hun. Bzun, esh-shitaa ra7 yiussal

Here, the days are more and more cloudy. I think winter is coming.

Al El 7adi2a alwatiniye [=el-wa6aniyye/-i] (al3am(?)) el2ariibe min hun msakkara 3ashan fi al el jau 3m ibarred w isa [missing portion here about the tourist. Here's my translation: iza shi saa2e7/saaye7 daa3] 7aikun fi kha[t]6ar mish bas 3al[i]eh. bas kamen 3shor[t]6a illi 7ddau[a]er 3ley [=3aleh](1).

the national park nearby has been closed because is getting too cold and, if a tourist loose the way, is not only dangerous for him but also for the police to find him.

al es-sauyya7 saaru a2all w a2all, w jeiin aktar shi min america [pronounced: amreeka/amerka] w min l'balaad al europa [pronounced: orobba] [or, min blaad/bled orobiyyi/eh].

tourists are less and less, and they come mainly from USA and many countries of Europe.

biraiy innu, b's-saiif, by[a]igieun a2al min 500 kil yom. byaussaluna bi l-bas w bi 6-[t]6ayyara. lazim [akeed would fit the context better, in my opinion] 3ndun masari ktir.

I think that, in the summer, they come no less than 500 per day. they come by bus and by plane. they must have a lot of money.

3adatan, biyas7un(?) [not sure what this word is, but I would say bitammu] usbu[h]3een 3la ala2l. fi naas ray[h]7ein 3la l'jabal la l-mashi, w fi naas illi biy[a]u2[u]3du [but for the sake of style, 2aa3diin would be better](2) bi l'mashghara la yerta7o.

they usually stay here at least two weeks. Some they go for trekking in the mountains, some they stay in town to relax.

hunne mu2addibiin, bass ktir min en-naas ma bye7ku lughatna, wa lahayk el7adiis ma3un sa3ab ktir.
lamma bataghadda ma3un , b7es inni mitl l'a[t]6rash fiz- zaffe!

they are polite but many of them they don't speak our language, that is why it is very difficult to talk with them. When I have lunchwith them, I feel lost!

(1) "3aley" (or "3alay") refers to the pronounce "me." "3aleh," on the other hand, refers to the pronoun "him" [the tourist].

(2) Because you wrote "ray7een," it sounds better to use a word like it (of the same grammatical category, "ism faa3el" rather than "fe3l") in the next part of the sentence, "2a3deen."

bil jabal - للهجة الشامية

Al aiam 3m bissir fi ghuyuum aktar w aktar hun. Bzun, es-shitaa ra7 yiussal

Here, the days are more and more cloudy. I think winter is coming.

Al 7adi2a alwatiniye (al3am) el2ariibe min hun msakkara 3ashan fi aljau 3m ibarred w isa 7aikun fi khatar mish bas 3ali. bas kamen 3shorta illi 7ddauar 3ley.

the national park nearby has been closed because is getting too cold and, if a tourist loose the way, is not only dangerous for him but also for the police to find him.

alsayya7 saaru a2all w a2all, w jeiin aktar shi min america w min l'balaad al europa.

tourists are less and less, and they come mainly from USA and many countries of Europe.

biraiy innu, b's-saiif, yagieun a2al min 500 kil yom. yaussaluna bi bas w bi tayyara. lazim 3ndun masari ktir.

I think that, in the summer, they come no less than 500 per day. they come by bus and by plane. they must have a lot of money.

3datan, biyas7un usbuheen 3la ala2l. fi naas rahein 3la l'jabal la mashi, w fi naas illi biya2u3du bi l'mashghara la yerta7o.

they usually stay here at least two weeks. Some they go for trekking in the mountains, some they stay in town to relax.

hunne muaddibiin, bass ktir min naas ma bye7ku lughatna, wa lahayk el7adiis ma3un sa3ab ktir.
lamma bataghadda ma3n , b7es inni mitl l'atrash fiz- zaffe!

they are polite but many of them they don't speak our language, that is why it is very difficult to talk with them. When I have lunchwith them, I feel lost!

It's difficult to understand everything when you write in English letters..

It's better to use real Arabic :)