Area Forecast Discussion
Issued by NWS Medford, OR
Issued by NWS Medford, OR
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
253 FXUS66 KMFR 021550 AFDMFR Area Forecast Discussion National Weather Service Medford OR 850 AM PDT Thu May 2 2024 .UPDATE...The main belt of precipitation within the area today lies just south of the ORegon/California state line, with scattered showers across the rest of the area. This precipitation will continue to move to the southeast and dissipate through the rest of the morning, with the area becoming almost entirely dry by afternoon. Some updates were made to the forecast to bring it in line with these current obs and the latest high resolution models, with the main effect of ending precipitation a bit earlier than previously thought. Otherwise, there were no significant changes. The previous discussion below contains more information on the rest of the forecast. -BPN && .AVIATION...02/12Z TAFs...Wind speeds along the coast have turned westerly with the front moving inland now. This will lead to rain showers diminishing through the morning hours with relief expected later today for ceilings. In fact, VFR could become common across the region with skies generally clearing through the afternoon and evening. North Bend may be the exception here with MVFR sticking around. Timing of MVFR and rainfall will be tricky this morning, but generally looking at the "roughest" conditions this morning with noticeable improvements later today. && .MARINE...Updated 230 AM Thursday, May 2, 2024...A weak front will continue to move through the waters this morning with a modest increase in short period west-northwest swell. A break later today will bring calmer conditions this afternoon and evening; however, the active pattern resumes Friday morning with rain over the waters likely (90% - 100%) and small craft advisory conditions in place through Saturday morning. Weak winds and a slight increase in short period west-northwest swell dominated seas are expected during the weekend with rainfall (no thunder) chances (60%-90%). The next in a series of fronts is likely to arrive on Monday with conditions hazardous to small craft possible Tuesday. -Guerrero && PREV DISCUSSION... /Issued 326 AM PDT Thu May 2 2024/ DISCUSSION...The pattern continues to be progressive into the next week, with several fronts bringing wet and cool weather with brief dry breaks in between. The first system moves through overnight today with light showers lingering into the evening, followed by a stronger front Friday into Saturday. Showery weather continues into next week, with another weak front moving through Monday. A broad precipitation shield associated with a frontal system is moving quickly ESE through southwest OR. Radar returns are indicating some pretty good areas of precipitation, with areas of 40-50 dbZ embedded in the main band. This front will pass through the region early this morning, followed by light, scattered showers which will bring on-and-off again precipitation for the remainder of the day, mostly over the higher terrain. With seasonably mild temperatures, snow levels will remain at or above 5,000 feet and snow restricted to the higher mountains. After a brief break in the weather, the next front arrives Friday and slowly pushes inland into Saturday. Similar to the frontal system today, this front will move in from the west, resulting in much less downsloping for western valleys than in other patterns. Precipitable water associated with this front, however, will be greater with a stronger inflow of moisture, resulting in greater precipitation amounts. Rain amounts of a half inch or more are almost guaranteed for almost all areas in southern Oregon and far northern California, with up to 2 or even 3 inches of rain possible along the coast. Snow levels will initially be quite high at the beginning of the event, rising to above 7,000 feet, before decreasing overnight Friday into Saturday to 3,000 to 4,000 feet as the cold front passes and precipitation becomes more intermittent/showery. This will result in snow lowering down to area passes, including those over the Cascades on Hwys 140 and 138 (where we`re expecting 3-6 inches early Saturday through early Sunday) and Siskiyou Summit on I-5 (likely less than an inch). As road surfaces are still quite warm, a lot of this will melt on paved surfaces, but lower visibilities could still make travel over the mountains difficult. Showery, on-and-off again precipitation continues late Saturday into Sunday as low pressure lingers aloft. Shower coverage will shrink and taper off through the day Sunday as the low moves SE and another transient ridge moves into the area. Another front moves in Monday, this one much weaker with the majority of light to moderate precip falling over northwest portions of the region. Snow levels will generally be 4,000 to 5,000 feet. Onshore flow and lingering moisture will lead to light, scattered showers continuing into Tuesday. About a third of models included in the National Blend indicate periods of precipitation are possible into the mid-week, but the outlook for the late week/following week is for warmer, drier conditions per the Climate Prediction Center. -CSP && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory from 8 AM Friday to 11 AM PDT Saturday for PZZ350-356-370-376. && $$