An anomalously strong ridge of high pressure will drive temperatures 15 to 25 degrees above normal through next weekend, with record high temperatures expected as early as Tuesday and a 90 to 100% chance of exceeding 80 degrees from the Treasure Valley to the Magic Valley.
Tonight and Monday: Warm Front Starts the Process
The area is currently sitting between an upper-level trough moving east through the Central Great Plains and high pressure building over the California coast, keeping today cool with below-normal temperatures and some breezy winds in the western Magic Valley.
A warm front will kick off the warming process tonight, bringing a dusting of snow to the northernmost mountains late tonight and Monday morning. Monday will feel near-normal with a high near 63 degrees and breezy conditions in the Snake Basin and southwest Idaho highlands, with gusts up to 30 mph in the afternoon. Skies will be mostly clear in southern areas and partly cloudy in the north.
Sizzling Heat Arrives This Week, Check out my Video Forecast.
Tuesday: Records Begin to Fall
The upper-level ridge will push temperatures dramatically higher on Tuesday, with highs jumping 10 to 20 degrees above normal in just one day. Record high temperatures are expected as early as Tuesday in southeast Oregon, with near-record highs in southwest Idaho. The upper-level heights and temperatures are reaching climatological maximums with this intense ridge, highlighting just how unusual this weather pattern is for mid-March.
Wednesday Through Saturday: Exceptional Heat Continues
Both ensemble and operational weather models are in very strong agreement on the ridge dominating the weather into next weekend, giving forecasters high confidence in the extended warmth. Temperatures will remain 15 to 25 degrees above normal area-wide Wednesday into Saturday, with lower valley highs approaching and likely exceeding records. There is a 90 to 100% chance of exceeding 80 degrees from the Treasure Valley to the Magic Valley, with highs reaching 80 degrees Thursday and Friday.
Residents should take this heat seriously, despite it being March. Stay hydrated, limit strenuous outdoor activity during peak afternoon hours, and check on elderly neighbors and family members who may be more vulnerable to the heat.
Pattern Change Possible Late Weekend
There are hints of a system late in the weekend that could bring temperatures closer to normal while introducing precipitation chances for northern areas. Ensemble data is trending toward this solution for Sunday and beyond, though details remain uncertain at this range.
Tonight
Mostly cloudy, with a low around 38. Calm wind.
Monday
Partly sunny & milder, with a high near 63. Light wind.
Monday Night
Partly cloudy, with a low around 41. Light wind.
Tuesday
Mostly sunny & pleasant, with a high near 73. Light and variable wind.
Tuesday Night
Partly cloudy, with a low around 46. Light and variable wind.
Wednesday
Sunny with record heat, with a high near 78.
Wednesday Night
Mostly clear, with a low around 49.
Thursday
Sunny with record heat, with a high near 80.
Thursday Night
Mostly clear, with a low around 52.
Friday
Sunny with record heat continuing, with a high near 80.
Friday Night
Partly cloudy, with a low around 52.
Saturday
Partly cloudy, breezy & not as warm, with a high near 72.
Saturday Night
Partly cloudy, with a low around 43.
Sunday
Partly sunny, breezy & cooler, with a high near 66.
