Area Forecast Discussion
Issued by NWS Medford, OR
Issued by NWS Medford, OR
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491 FXUS66 KMFR 240951 AFDMFR Area Forecast Discussion National Weather Service Medford OR 251 AM PDT Fri May 24 2024 .DISCUSSION... An upper level wave is currently pushing into Oregon and we`ll see widespread synoptic lift through the day. We`re anticipating some mid and high level cloud cover with showers forming generally in the northern sections of the forecast area with drier conditions towards the south west. There is also a low (5-15%) chance of cloud to ground lightning within 25 miles of any point east of the Cascades later today. There isn`t a lot of available moisture for potential instability, and cloud cover could inhibit convection as well. Other than storms, it shouldn`t be as windy compared to Wednesday when a wave swung through the forecast region, however there should be some stronger breezes east of the Cascades and in some of the valleys later today. By Friday night, high pressure should begin to build as the wave departs the region. Precipitation chances should generally decrease into the later evening hours. There is some evidence that the air has some instability on Friday night along the coast, so a low chance of rain showers will persist there overnight. Not much will change on Saturday as high pressure continues to build and the flow pattern remains out of the west and northwest. However, the air is cooler behind this wave, so we`ll see temperatures trend a few degrees cooler compared to Friday. High temps will remain 5 degrees cooler than normal for late May. Conditions continue to dry into Sunday with temperatures moving a few degrees higher and high pressure continuing to build. By the start of next week, high pressure will remain in place with highs shooting into the mid 80`s to upper 70`s within valleys west of the Cascades on Monday. High temps will cool slightly into Tuesday as another upper level wave likely pushes into Oregon and much of the Pacific Northwest. Depending on when the wave actually arrives, there is a threat of some thunderstorms on Tuesday evening or perhaps Wednesday evening. Once the upper level wave passes on Wednesday, we`ll probably see high pressure build towards the end of next week. However, the NBM still has some low chances of precipitation along the Cascades and in the northern sections of our forecast areas. There is about a 10 to 15% chance of precipitation on Thursday evening and Friday evening. A cluster analysis shows some ensemble members with an upper level wave over us Thursday evening while some some have high pressure well in control. Therefore, it`s pretty hard to say what will happen towards the end of next week. -Smith && .AVIATION...24/06Z TAFs...VFR conditions are expected to continue through the TAF period for inland areas, with breezier afternoon and evening winds at all terminals. An approaching weak frontal system looks to push the marine layer and its accompanying lower stratus, currently well offshore, inland ahead of it tonight. A brief period of MVFR conditions along the northern Curry and Coos county coasts is likely later tonight. Northwesterly breezes will pick up ahead of the front in the early afternoon and continue into the evening as the front approaches, but winds won`t be as significant as the system that passed through earlier this week. Showery, spotty precipitation will move onshore and inland Friday afternoon and evening. Best chances will be in northern portions of the region (northern Douglas, Coos, Klamath, and Lake counties) as well as along the south OR Cascade crest. Additionally, there is about a 10-15% chance for isolated thunderstorms developing later in the afternoon into the evening in southern and eastern Lake and Modoc counties. -CSP && .MARINE...Updated 200 AM Friday, May 24, 2024...The current Small Craft is due to end at 11 pm pdt with a brief break until Friday afternoon while north winds gradually diminish in the expansion fan. A weak front will move through the waters with moderate northwest winds with gusts up to 25 kts possible this evening through Saturday morning. Steep seas are expected in all waters, with another Small Craft Advisory covering all waters today at 5 PM until Saturday at 5 PM pdt. Past Saturday evening, upper level stability will guide conditions into the middle of next week. Currently calm seas are forecast from Saturday evening through at least next Tuesday. -Petrucelli/Hermansen && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT early this morning for PZZ350-356-370-376. && $$