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MLO Visitor's Telescope at sunset Looking out the 24-inch telescope dome at twilight The ULTRA telescope building with lupines
photo of sunset taken at MLO showing distorted shape of the sun

Sunset through the cloud inversion layer as seen from MLO. This inversion layer helps block light pollution from San Diego.

SDSU Mount Laguna Observatory Weather


Click for Mount Laguna, California Forecast. HPWREN Mount Laguna 360 degree Web Cams (Other HPWREN Web Cams)



  • Current Fire Danger Levels in the Cleveland National Forest.
    If the conditions are in the "black critical zone", MLO will be closed. Outdoor use of power tools is prohibited unless conditions are at "low" or "moderate" levels.
  • San Diego County Road Closures (due to snow, fires).
    Reminder: Sunrise Highway is also known as "S1".

    • The current Universal Time: UTC clock
      (clock runs for 15 s then this page needs to be reloaded to maintain accuracy)
    • A snapshot of the "official US time" (in UT) from the US Naval Observatory & the NIST. Another single instantaneous reading from the US Naval Observatory Master Clock Time.
    • A JD-to-calendar date converter from the USNO.
    • To see the current MJD, press this button: .


    MLO Clear Sky Clock tool The "Clear Sky Clock" for Mount Laguna Observatory generated by Attilla Danko. Click on the image for more information.