Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
790 FXUS65 KBOI 160241 AFDBOI Area Forecast Discussion National Weather Service Boise ID 841 PM MDT Sat Jun 15 2024 .DISCUSSION...Breezy, cool weather under an upper level trough will become even colder Sunday night and Monday as a deep upper low within the trough passes over our CWA. The low will bring showers mainly to northern and central areas, with snow as low as 4500 feet MSL late Sunday night and Monday morning. As the low tracks eastward Monday, moisture wrapping around it may bring rain showers as far south as the Treasure Valley. Tuesday will begin a warming and drying trend that will continue the rest of the week, with high temperatures possibly reaching 100 degrees in the lower southern valleys next weekend. Current forecast is on track and is well-supported by latest models. && .AVIATION...Significant trough of low pressure to impact the region beginning late Sunday. Precipitation to impact most terminals after 20Z Sunday, with the best chances 20-60% after 00Z Monday. Snow levels 5000 to 6000 feet by late Sunday, with terrain obscuration likely across northeast Oregon and central Idaho. Surface winds: W-NW 15-25 kt with gusts to 35 kt, diminishing to 5-15 kt with gusts to 25 kt by 06Z. Winds aloft at 10kft MSL: W 15-30 kt. KBOI...VFR. Surface winds: NW 10-15 kt with gusts to 25 kt diminishing to less than 10 kt by Sun/04Z. && .PREV DISCUSSION... SHORT TERM...Tonight through Monday night...A spring-like pattern will continue through the short term. Upper level troughing will persist to our north on Sunday, keeping temperatures around 10 degrees below normal with dry conditions. An unseasonably cold and deep upper low (near record cold and deep for mid June) will move from the Washington coast into our area Sunday night and Monday. The low will push another cold front across the area Sunday night, bringing even cooler temperatures and lowering snow levels. Precipitation will increase across southeast Oregon and southwest Idaho Sunday night with the bulk of the rain and snow late Sunday night and Monday. The low center is currently favored to move east near McCall, keeping the highest (60-80%) chance of showers across the central Idaho mountains. This will result in only a 15-30% chance of rain in the Treasure Valley with less than a 10% chance in the Magic Valley. Snow levels will fall to 4500-6000 feet by Monday morning, with 2-6 inches of snow possible at elevations above 6000 feet. Rain may mix with snow in McCall Monday morning although little to no snow accumulation is expected. A 10-20% chance of thunderstorms will develop Monday afternoon across the mountains. Showers will taper off by Monday evening as the low center moves east. High temperatures on Monday will be around 15-20 degrees below normal. Winds will be gusty behind the cold front, with peak gusts 25-40 mph, except up to 50 mph east of Mountain Home into the Camas Prairie and Magic Valley. Winds will subside Monday evening. Low temperatures Monday night will be quite cool, generally in the lower 40s in the Treasure Valley, but potentially dipping into the mid to upper 30s from near Mountain Home east through the Magic Valley. LONG TERM...Tuesday through Saturday...An upper level trough will remain overhead on Tuesday, but will be much weaker than Monday`s system. Temperatures should rebound around 10 degrees from Monday, but will still be 5-10 degrees below normal. Lingering moisture will result in a 15-25% chance of showers and thunderstorms across the central Idaho mountains Tuesday afternoon with dry conditions elsewhere. The upper level trough will continue to weaken through the end of the week with southwest flow aloft returning. This will allow temperatures to warm several degrees each day, reaching around 10 degrees above normal by Friday and Saturday. Conditions will remain dry with generally light winds. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...LC AVIATION.....MC SHORT TERM...ST LONG TERM....ST