اليوم الاحد, و حاليا الطقس منيح.جيد

مشمسيا و غيوم جزايا.ئي

انا بقعد عطاولة برة اجلس على طاولة خارج المقهوة مع رفيقي.

اليوم الاأحد, و حاليا الطقس منيحجيّد.

منيح isn't used in traditional arabic to mean "Good" or "Nice".
And الأحد with a أ after the laam, not a ا.
also حاليا is correct, but the one more associated with trad arabic is حالا.

درجة الحرارة شوب شوي بس لما في تُشَوِّبُ قليلا لكن لما تأتي الرياح هيتصبح معتدلة.

use تُشَوِّبُ instead of شوَّبَ, as the latter means "felt hot" and the former means "makes one feel hot". Or you can use "مُرْتَفِعة" which means high, and it'll just mean "the temperature is high".
شوي isn't Trad Arabic. It's more Levantine.
قليلا = a little.
you can play with that last section in multiple ways and all of them will be valid. So, you can say: لكن حِينَ تأتي الريح تصبح معتدلة or
ولكن عندما يكون هناك ريح تكون مُعتدلة and such. The composition you made isn't really colloquial. and بس isn't Trad arabic.

شمسيا و غيومالجو مُشمِسُُ ولكنه غائمُُ جزائيا.

the adjective form is مُشْمِس.
It would seem weird to say وغائمُُ جُزْئيا so it'd be better if one said "but it's..."
it's جُزئيا not جزايا. the ء is part of the original 3 lettered root.

الدرجة بفي السبعينات و في كتير عصفوهناك عصافير و أُناس برةكثيرة في الخارج بسبب الطقس قويسالجيد.

you said in english "the temperature", what prevented you from putting the ال in arabic?
في sounds more natural, though the form في السبعينات seems kinda weird.
عصفور is singular, plural is عصافير. and the adjective comes after the noun so عصافير كثيرة and عصافير is also feminine.
and use ناس كُثُر or أُناس كثيرة. And since you described the birds and the people with one state, it's only sound to put that state after both of them are added together with the و. Or, more like, it's more colloquial this way. Though the other way around is weird.
you most prolly wanted to write كويس not قويس, but not MSA.

انسإن شاء االله رح يضل هالطقس العظيم.