Denver’s forecast calls for a mostly sunny day Thursday with highs in the 90s and some wind with gusts up to 28 mph, according to the National Weather Service in Boulder.

A dramatic shift on Friday is expected to bring colder temps, with highs in the 40s and a 90% chance of rain. Thunderstorms are also possible in the afternoon.

Temps are projected to sink into the high 20s or low 30s on Friday and Saturday nights. Rain and snow showers are expected overnight Friday, with new snow accumulations between 1 and 3 inches.

Wet weather is expected continue through Saturday afternoon, with an 80% chance of precipitation.

NWS Boulder tweeted: “A heavy, wet snow will fall on Friday and Saturday with roughly 3-10” in metro Denver, 8-12”in the Palmer Divide & over 2 feet near the Continental Divide. Considering leaf out has occurred, downed trees-branches and power outages will be a significant threat.”

NWS Boulder is also cautioning travelers in the Rocky Mountain National Park area. “Have plans at @RockyNPA this weekend? If you still plan to travel, it’s time to prepare for as much as 30” of snow. Expect treacherous travel Fri-Sat.”

Here’s the forecast from the National Weather Service.

Thursday: Mostly sunny, with a high near 90. Breezy, with a south wind 9-14 mph becoming west 15-20 mph in the afternoon. Winds could gust as high as 28 mph.

Friday: A chance of showers, then showers and possibly a thunderstorm after noon. High near 49. East wind 9-11 mph becoming north northeast in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 90%.

Friday night: Rain showers before 8 p.m., then rain and snow showers between 8 p.m.- 4 a.m., then snow showers after 4 a.m. The snow could be heavy at times. Some thunder is also possible. Low around 32. North wind 7-10 mph. Chance of precipitation is 100%. New snow accumulation of 1-3 inches possible.

Saturday: Snow showers before noon, then rain and snow showers likely. Some thunder is also possible. High near 41. Northeast wind 7-9 mph, with gusts as high as 16 mph. Chance of precipitation is 80%.

Saturday night: A chance of rain showers before 8 p.m., then a chance of rain and snow showers between 8pm and 4am, then a slight chance of snow showers after 4 a.m. Some thunder is also possible. Mostly cloudy, with a low around 28. Chance of precipitation is 30%.

Sunday: A 30% chance of showers and thunderstorms after noon. Mostly sunny, with a high near 52.