Monday could be the warmest day so far in 2018, and certainly the warmest day for the rest of the week.

Ahead of a cold front, widespread afternoon readings will jump to the 60s and 70s in Southern Montana and Northern Wyoming. Expect the 40s in Eastern Montana and North Dakota.

It is possible that Sheridan, Wyoming could hit the upper 70s to low 80s. The April 16 reccord high at the Sheridan airport is 82.

As a cold front approaches, clouds and wind will increase this afternoon, followed by rain and possible thunderstorms this evening. Wind gusts could hit 40 to 45 mph.

Rain and snow showers develop tonight, with some light accumulations possible in Big Horn County, Montana (Hardin) and Sheridan County, Wyoming (Sheridan) by Tuesday morning.

Cooler temperatures will follow, with highs mainly mid-to-lower 50s the rest of the work week, and lows in the upper 20s to mid 30s.

Billings forecast:

Monday….Mostly sunny with a high near 73. Winds increase in the afternoon.

Monday night…Mostly cloudy with rain showers likely by late evening. Northerly winds increase with gusts to 45 mph. Low of about 37.

Tuesday…A chance of rain or rain/snow showers early. Mostly cloudy with a high around 52. A chance of morning rain or snow showers with a westerly wind 15 to 25 mph.