Yes, it'll probably snow this week. But how much will we get?

Sunny skies and mild temperatures will once again give way to cold and snow in Northern Colorado, so will that ruin your outdoor graduation plans for this weekend?

Well ... if nothing else, you'll get winter weather whiplash.

The National Weather Service has issued a winter storm watch for a large area of the state with estimates of 1 to 3 feet of snow in the mountains and northern foothills, including Rocky Mountain National Park. Those areas should see snowfall through Friday, according to NWS. The watch goes from Thursday evening to Friday afternoon.

Fort Collins and the rest of the urban corridor will have to wait a little longer. NWS predicts snow for Fort Collins late Thursday night and early Friday morning. High school graduations in Fort Collins run Thursday through Saturday with all ceremonies inside, but that may force your parties inside, unless you wait until Saturday.

The heavy, wet snow in Fort Collins will be mixed with cold temperatures and plenty of rain, and both NWS and 9News meteorologist Marty Coniglio say the snow probably won't stick to the ground much.

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NWS predicts a modest total of about an inch in Fort Collins, while 9News predicts 2 to 5 inches for Fort Collins and surrounding areas.

Our rainfall should be more impressive. Rain will return to Fort Collins and it should continue through Friday morning at least, according to NWS.

NWS predicts up to 4 inches of rain through Friday in Fort Collins. For reference, that's nearly as much precipitation as Fort Collins has received since early January, all falling in a three-day period. Phew.

Expect the heaviest rain on Thursday, particularly between noon and 6 p.m.

Temperatures will steadily and we'll hit the 40s by mid-afternoon Thursday. 

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The chance of rain shrinks to about 30 percent by Friday night, and by Saturday the sun should return, bringing a high of 56 along with it.

If snow falls on Thursday, May 18, it will be the latest snowfall Fort Collins has seen since 2002, when snow fell May 24. Fort Collins generally bids adieu to snow by early May but occasionally gets a late-May or early-June snow. Our latest-ever snow was June 12, 1947, according to the Colorado Climate Center.

Sprinkler systems should be OK, as Fort Collins' lowest low is 31 degrees Friday night, according to NWS. If we do get heavy snow, make sure to brush it off trees to prevent limb breakage.

NWS snow predictions

Fort Collins: 1 to 2 inches

Windsor: 1 to 2 inches

Estes Park: 18 to 24 inches

Boulder: 1 to 2 inches

Loveland: 1 to 2 inches

Greeley: Less than 1 inch