fetch data is updated but array and state is not updated - reactjs

Question

i am woking on weather api and storing perticular data in an array arr but value is not available in arr. also state arrdata is null too.
i tried to not use state but still not getting data in arr . it show reading undefined value.
export default function App() {
const [cityName, setCityName] = useState("delhi");
const [arrData, setArrData] = useState(null);
const getWeatherInfo = async () => {
const url = "https://api.openweathermap.org/data/2.5/forecast";
const api = "4beffc863037e89f0f181d893d1cf79b";
fetch(`${url}?q=${cityName}&units=metric&appid=${api}`)
.then((res) => res.json())
.then((getData) => {
if(getData.list[4].main !== null){
const arr = [];
for (let i = 0; i <= 40; i++) {
if (i % 8 === 0) {
arr.push({
temprature: getData.list[i].main.temp,
Min_temp: getData.list[i].main.temp_min,
Max_temp: getData.list[i].main.temp_max,
date: getData.list[i].dt_txt,
mood: getData.list[i].weather[0].main,
weathermoodIcon: getData.list[i].weather[0].icon,
Humidity: getData.list[i].main.humidity,
});
}}
setArrData(arr);
}});
};
useEffect(() => {
getWeatherInfo()
}, []);
console.log(arrData)
const onInputChange = (e) => {
setCityName(e.target.value);
};
const onSubmitCity = () => {
getWeatherInfo();
};
return (
<>
<Input onChangeValue={onInputChange} onSubmit={onSubmitCity} />
</>
);
}

Answer 1

This seems to be working. Please do not forget to use optional chaining
import {useState, useEffect } from 'react';
export default function App() {
const [cityName, setCityName] = useState("delhi");
const [arrData, setArrData] = useState(null);
const getWeatherInfo = async () => {
const url = "https://api.openweathermap.org/data/2.5/forecast";
const api = "4beffc863037e89f0f181d893d1cf79b";
fetch(`${url}?q=${cityName}&units=metric&appid=${api}`)
.then((res) => res.json())
.then((getData) => {
if(getData.list[40]?.main !== null){
const arr = [];
console.log(getData.list)
for (let i = 0; i <= 4; i++) {
if (i % 8 === 0) {
arr.push({
temprature: getData.list[i]?.main.temp,
Min_temp: getData.list[i]?.main.temp_min,
Max_temp: getData.list[i]?.main.temp_max,
date: getData.list[i]?.dt_txt,
mood: getData.list[i]?.weather[0].main,
weathermoodIcon: getData.list[i]?.weather[0].icon,
Humidity: getData.list[i]?.main.humidity,
});
}}
setArrData(arr);
}});
};
useEffect(() => {
getWeatherInfo();
}, []);
console.log(arrData)
const onInputChange = (e) => {
setCityName(e.target.value);
};
const onSubmitCity = () => {
getWeatherInfo();
};
return (
<>
<input onChange={onInputChange} onSubmit={onSubmitCity} />
<h1> {JSON.stringify(arrData)} </h1>
<button onClick = {onSubmitCity}> Submit </button>
</>
);
}