I am scheduled to hike Mt. Whitney this September 22-23. I reserved a camp site at the portal (day 1) then plan to hike up to Outpost Camp (day 2), and then summit and down (day 3). Does anyone know where I can find the anticipated temperatures (day and night) at each altitude? I have used the website mountain-forecast.com in the past with much reliability, however it is only good for the upcoming 1 week of forecast. Thanks!