Deep monsoon moisture continues to stream into the region, bringing widespread showers and thunderstorms tonight and Tuesday with the potential for locally heavy rainfall and gusty outflow winds, before dangerous heat returns with temperatures around 100 degrees or higher through the weekend.
Thunderstorms to hit some areas in Scott Dorval's video forecast
The large-scale pattern remains locked in place with a broad high over the interior West and an upper trough off the Pacific Northwest coast. Southerly flow aloft continues to transport deep monsoon moisture into the region. Cloud cover is limiting heating this afternoon, which will also limit thunderstorm development today. Showers and storms that develop could bring outflow gusts to 40 mph.
A weak upper disturbance will bring another chance of showers and possible thunderstorms starting Tuesday morning, with instability carrying the threat into the evening. As moisture values climb well over an inch, heavy rain will be possible from storms that develop. This threat will be focused across southeast Oregon and along the Idaho-Nevada border where the best heating and instability sets up. Gusty outflow winds to 40 mph will also be in play. Locally heavy rainfall could affect burn scars across southeast Oregon, raising flash flood concerns.
Wednesday will bring clearing skies and hotter conditions as drier air moves in aloft. High temperatures will warm back above normal, reaching the mid to upper 90s at lower elevations.
Hot south-southwesterly flow will persist through early next week, with consistent afternoon shower and thunderstorm chances over high terrain in central and south-central Idaho. For the rest of the area, temperatures will heat back up significantly. The Snake River Plain and adjacent lowlands will see regular afternoon highs around the 100-degree mark, and the forecast has continued to trend warmer. The heat could become hazardous if this trend continues, especially heading into the weekend. By Monday, storm activity would shift from the mountains down to the Nevada border across Oregon and Idaho as the North American Monsoon pattern takes hold.
Residents should take precautions during both the thunderstorm threat and the upcoming heat. Stay weather aware during storms, avoid areas near burn scars during heavy rain, and take steps to stay cool and hydrated during the dangerous heat.
Tonight
Increasing clouds, with a low around 70. Northwest wind 5 to 8 mph becoming calm in the evening.
Tuesday
A slight chance of showers and thunderstorms between noon and 3pm. Mostly cloudy and hot, with a high near 92. Calm wind becoming northwest 5 to 9 mph in the morning. Chance of precipitation is 20%.
Tuesday Night
Mostly cloudy, with a low around 64. Northwest wind around 6 mph becoming calm in the evening.
Wednesday
Sunny and hot, with a high near 97. Calm wind becoming west northwest 5 to 8 mph in the afternoon.
Wednesday Night
Clear, with a low around 64.
Thursday
Sunny and hot, with a high near 101.
Thursday Night
Mostly clear, with a low around 66.
Friday
Sunny and hot, with a high near 101.
Friday Night
Partly cloudy, with a low around 66.
Saturday
Sunny and hot, with a high near 101.
Saturday Night
Partly cloudy, with a low around 68.
Sunday
Mostly sunny and hot, with a high near 101.
Sunday Night
Partly cloudy, with a low around 67.
Monday
A slight chance of showers. Partly sunny and hot, with a high near 100.
