759 FXUS65 KBOI 191609 AFDBOI Area Forecast Discussion National Weather Service Boise ID 1009 AM MDT Sat Jun 19 2021 .DISCUSSION...Warm and dry conditions today under a weak upper level ridge. The ridge does get suppress some by a passing upper level trough and cold front which will keep temperatures a few degrees cooler than yesterday. The frontal passage will bring wind gusts up to 30 MPH with its passage late this afternoon/evening especially across Southwest Idaho. Minor update to winds today otherwise, forecast remains on track. Update will be out shortly. && .AVIATION...VFR. Mostly clear skies. Surface winds: generally west to northwest 10-20 kts with gusts up to 25 kts this afternoon. Winds aloft at 10kft MSL: West 5-20 kts. Hot temperatures today will lead to increased density altitude. Sunday Outlook...VFR. Clear skies. Gusty surface winds of 10 to 20 kts will develop in the afternoon. && .PREV DISCUSSION... SHORT TERM...Today through Monday night...Hot and dry again today. Pacific cold front will arrive too late to bring significant cooling today, but Sunday will be several degrees cooler under northwesterly flow aloft. The front will bring gusty northwest winds up to 30 mph late today and this evening. Post-frontal cooling will last only one day before a short wave upper ridge comes in from the Pacific Monday and connects with the main upper ridge and hot air mass in the Great Basin. On Monday night an upper low off California will develop a slight chance of thunderstorms in central and eastern Oregon. Any thunderstorms will have gusty outflow winds but little rain. LONG TERM...Tuesday through Saturday...An upper low approaching the northern CA coast will inject mid-level moisture into the region as reflected in precipitable water values approaching an inch across portions of the area Tuesday afternoon. Coupled with the heat, this will fuel afternoon showers and thunderstorms over higher terrain. The upper low will linger, keeping the chance for afternoon convection over the area through Thursday. Friday into the weekend will trend drier and hotter as the persistent SW US high builds northward. Temperatures will be above normal through the period. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...JS AVIATION.....MC PREV SHORT TERM...LC PREV LONG TERM....DG