Area Forecast Discussion
Issued by NWS Missoula, MT
Issued by NWS Missoula, MT
719 FXUS65 KMSO 080831 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 231 AM MDT Wed May 8 2024 .DISCUSSION...Low pressure east of the Continental Divide is sending wraparound moisture over the Divide and into western Montana this morning. Radar returns and satellite imagery point to increasing widespread precipitation across the Northern Rockies. The heaviest precipitation is, and will continue to be, over the Continental Divide as the terrain is providing much of the forcing for ascent of moist air. Snow levels will be about 4000-4500 feet, keeping precipitation in the form of snow over the Divide and in Butte and the Georgetown Lake area. Liquid precipitation by Wednesday evening will likely (80-90 percent chance) exceed 1 inch in the aforementioned areas. In the higher terrain, this would translate to 8 to 12 inches of snow, with locally higher amounts along the Divide. Expect winter travel conditions over the mountain passes traversing the Divide such as Homestake, MacDonald, Rogers, and Marias Passes through this morning. This afternoon, the low moves east and takes the moisture with it. A drying trend will begin this afternoon. Forecast models are very consistent in folding a ridge of high pressure over western Montana and north central Idaho Thursday into the weekend. A rapid warm up is anticipated, with temperatures approaching the upper 70s and low 80s in the valleys by Saturday and Sunday. In fact, current model guidance shows a roughly 60 percent chance of Missoula hitting 80 degrees by Monther`s Day. High pressure will likely remain in place through early next week. However, by Wednesday, about 30 percent of model guidance begins to indicate the potential for another trough of low pressure. && .AVIATION...Rain, and snow at KBTM, will continue at all Northern Rockies terminals through about 08/22Z this afternoon. Precipitation will obscure terrain through this afternoon, primarily along the Continental Divide. Gusty winds will also persist through this afternoon, shifting to the north as the low pressure system east of the Divide moves east. Precipitation will taper off this evening and winds will relax as high pressure begins to build. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Winter Weather Advisory until 11 AM MDT this morning for Bitterroot/Sapphire Mountains...Butte/Blackfoot Region... West Glacier Region. ID...None. && $$