Area Forecast Discussion
Issued by NWS Boise, ID
Issued by NWS Boise, ID
253 FXUS65 KBOI 161532 AFDBOI Area Forecast Discussion National Weather Service Boise ID 932 AM MDT Tue Jul 16 2024 .DISCUSSION...Clouds already spreading northward into Oregon will lead to scattered thunderstorms this afternoon and tonight especially in Harney County. A Red Flag Warning for lightning now in effect for the Burns/OR BLM. Rest of early morning forecast is on track showing a 20 to 40 percent chance of thunderstorms Wednesday and Thursday afternoons in southern Owyhee and Twin Falls Counties, then extreme heat again in our CWA late this week through Monday. Excessive Heat Watch is currently in effect Thursday through Monday but may need to be extended through Tuesday. && .AVIATION...Smoke over most of the area, especially near KMYL/KONO/KBNO. Scattered showers and thunderstorms with gusty outflow winds this afternoon in SE Oregon, Isolated thunderstorms extending as far east as Owyhee County/ID. Oregon storms will move northeast through the evening while Idaho should dissipate by sunset. High density altitude due to hot daytime temperatures. Surface winds: variable 10 kt or less, except gusts to 50 kt near showers/storms. Winds aloft variable 5-15 kt. KBOI...Mostly VFR. Smoke may reduce visibility below 6 miles, but thicker smoke should stay northwest of KBOI. High density altitude due to hot daytime temperatures. Light winds through 18Z, then NW 6-12 kt with gusts to 16 kt. && .PREV DISCUSSION... SHORT TERM...Today through Thursday night...Although an upper level ridge will dominate our weather for quite some time, there is a trough that will bring an increased chance of showers and thunderstorms later today through Wed. This trough was located off the coast of northern CA this morning, and will move northeast through Wed night. It will move by mainly to our northwest, but will be close enough to bring the previously mentioned increasing chance of convection. Apart from that, we will get hotter each day, even though smoke is expected to generally increase. Temps will rise from around 5 degrees above normal today, becoming closer to 10 degrees above normal Thursday. An Excessive Heat Watch remains in effect from Thursday afternoon into the long term period. No changes will be made to the watch at this time. The best chance for showers and storms today through Wed will be in southeast Oregon and in southern and western Owyhee County. Gusts to 60 mph are possible in outflow. Finally, area fires are expected to burn vigorously over the next few days as hot unstable conditions continue. LONG TERM...Friday through Tuesday...An upper level ridge located over the Four Corners region will build northwest into NV over the long term period. The ridge axis will be located over our area, bringing us another extended period of extreme heat. An Excessive Heat Watch was issued yesterday and is valid Thursday through Monday, and this may end up being extended into Tuesday. Temperatures should be 10-15 degrees above normal through the long term, depending on how much smoke we get. We should be mostly dry due to the upper ridge. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Excessive Heat Watch from Thursday afternoon through Monday evening IDZ012-014-016-030-033. OR...Excessive Heat Watch from Thursday afternoon through Monday evening ORZ063-064. Red Flag Warning from 2 PM this afternoon to 11 PM PDT this evening ORZ636. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...LC AVIATION.....LC SHORT TERM...SP LONG TERM....SP