expect_weather: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/expect_weather - from package: expect

You may install the required package with command apt-get install {package}
Error in other languages:
expect_weather: bevel nie gevind nie
expect_weather: comandă negăsită
expect_weather: comando não encontrado
expect_weather: commande introuvable
expect_weather: command not found
expect_weather: käsku ei ole
expect_weather: không tìm thấy lệnh
expect_weather: komanda nerasta
expect_weather: Kommando nicht gefunden.
expect_weather: kommandot finns inte
expect_weather: komut yok
expect_weather: nie znaleziono polecenia
expect_weather: níor aimsíodh an t-ordú
expect_weather: no se encontró la orden
expect_weather: no s'ha trobat l'ordre
expect_weather: opdracht niet gevonden
expect_weather: parancs nem található
expect_weather: perintah tidak ditemukan
expect_weather: príkaz nenájdený
expect_weather: příkaz nenalezen
expect_weather: команда не найдена
expect_weather: командата не е открита
expect_weather: 命令找不到
expect_weather: コマンドが見つかりません