Watching Hurricane Erin; Heavy Rainfall Threat for Upper Midwest; Heatrisk for Mississippi Valley

Hurricane Erin continues to track westward with its outer bands bringing heavy rainfall and gusty winds for Puerto Rico and US Virgin Islands. Life-threatening surf and rip currents are occurring and will spread across the Atlantic coasts this week. Meanwhile, heavy rainfall and possible flooding are in the forecast for upper Midwest through Monday. Heatrisk continues for the Mississippi Valley. Read More >

Hazardous Weather Conditions

Special Weather Statement

Current conditions at

Lewistown, Lewistown Municipal Airport (KLWT)

Lat: 47.04917°NLon: 109.46639°WElev: 4167.0ft.

Clear

80°F

27°C

Humidity	39%
Wind Speed	N 0 MPH
Barometer	29.98 in (1015.24 mb)
Dewpoint	53°F (12°C)
Visibility	10.00 mi
Heat Index	80°F (27°C)
Last update	17 Aug 04:54 PM MDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

Lewistown MT

This Afternoon
High: 79 °F
Chance
T-storms
Tonight
Low: 54 °F
Heavy Rain
then Partly
Cloudy
Monday
High: 86 °F
Sunny then
Slight Chance
T-storms
Monday Night
Low: 58 °F
Mostly Clear
Tuesday
High: 92 °F
Sunny
Tuesday Night
Low: 59 °F
Mostly Clear
Wednesday
High: 90 °F
Sunny
Wednesday Night
Low: 56 °F
Slight Chance
T-storms
Thursday
High: 79 °F
Mostly Sunny

Detailed Forecast

This Afternoon

A 50 percent chance of showers and thunderstorms. Partly sunny, with a steady temperature around 79. Northeast wind around 6 mph.

Tonight

Showers and thunderstorms likely, mainly before 9pm. Some of the storms could produce heavy rainfall. Cloudy during the early evening, then gradual clearing, with a low around 54. South southwest wind around 6 mph becoming calm after midnight. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.

Monday

A 20 percent chance of showers and thunderstorms after 3pm. Sunny, with a high near 86. Calm wind becoming east northeast around 6 mph in the afternoon.

Monday Night

Mostly clear, with a low around 58. West northwest wind around 5 mph becoming east southeast in the evening.

Tuesday

Sunny, with a high near 92. Calm wind becoming southwest around 6 mph in the afternoon.

Tuesday Night

Mostly clear, with a low around 59. North northeast wind around 7 mph becoming south after midnight.

Wednesday

Sunny, with a high near 90. South southwest wind 6 to 9 mph becoming northwest in the afternoon. Winds could gust as high as 18 mph.

Wednesday Night

A slight chance of showers and thunderstorms. Partly cloudy, with a low around 56. North wind 5 to 8 mph becoming southwest after midnight.

Thursday

Mostly sunny, with a high near 79.