It'll be the longest partial lunar eclipse in almost 600 years.

By: KDKA-TV News Staff

PITTSBURGH (KDKA) – The clouds over Pittsburgh are expected to roll out just in time for Friday morning’s partial lunar eclipse.

READ MORE: Partial Lunar Eclipse To Take Place Friday Morning

While there’s been a narrow window for clear skies all week, KDKA Meteorologist Ron Smiley says Pittsburgh should get lucky. The cloud cover should break before the eclipse and return when it’s over.

The eclipse starts at 1 a.m. and goes until 7, peaking around 4. With the peak lasting nearly three and a half hours, it will be the longest partial lunar eclipse in almost 600 years.

Photo Credit: KDKA Weather Center

It’s not a full lunar eclipse, but it’s pretty close. About 97.4% of the reflective portion of the moon will be covered in the earth’s shadow.

READ MORE: Pittsburgh Weather: Consistent Rain Throughout The Morning And Afternoon

“Because the moon will arrive at apogee — the farthest point in its orbit from Earth — on Nov. 20, it will also be moving at its slowest speed in its orbit,” Joe Rao explained on “That’s why it will seem to move at an almost ‘leisurely pace’ through the Earth’s shadow, taking over 100 minutes from the time of first umbral contact to the time of greatest eclipse, and vice versa.”

WATCH: Ron Smiley Explains The Eclipse

The eclipse will be visible from North America where skies are clear.

If the weather in your area is not cooperating, you can watch it online. The Griffith Observatory in Los Angeles, California will stream the partial — “but practically total!” — eclipse on YouTube.

You can also catch coverage on KDKA’s Your Day Pittsburgh.