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
815 FXUS66 KMFR 052149 AFDMFR Area Forecast Discussion National Weather Service Medford OR 249 PM PDT Sun May 5 2024 .SHORT TERM...Through Wednesday morning...Upper flow aloft around a low pressure system to the east of our area counties to bring showery activity across northern California and southern Oregon. For this afternoon, radar indicates that a wide area of showers remains over Lake, Modoc, and eastern Klamath counties with generally scattered showers elsewhere. This activity will decrease steadily overnight, with 20-40% chances of showers remaining over the Coos County coast and the Cascades through this evening. Cold overnight temperatures remain in the forecast for Monday morning. There is high confidence in the temperatures for the Shasta and Scott valleys returning to at or below freezing tonight. A Freeze Warning has been issued for these areas from 2 AM through 9 AM on Monday morning to communicate this expected hazard. Similar to Sunday morning, the chance for near or at freezing temperatures in the southern Rouge and Illinois valleys remains, but is slight (5- 10%) and is not enough to support additional warnings for those areas. A warm front will bring another round of activity on Monday, with showers arriving on the Oregon coast in the early hours of the morning and moving eastward through the day. Amounts look inconsequential, with a quarter to half an inch of rain over coastal areas and 2 to 6 inches of snow over the Cascades through Monday. This front will also bring gusty winds, especially to areas east of the Cascades. A Wind Advisory will be in effect on Monday from 11 AM to 8 PM for northeast Lake County as gusts exceeding 40 mph are expected in this area. Post-frontal showers will continue over the Oregon coast and the Cascades through the day Tuesday, but conditions look to be stable otherwise. Temperatures will start to warm as the upper trough moves away to the east. Afternoon gusty winds will be present east of the Cascades again, but are not forecast to reach Advisory levels. -TAD .LONG TERM...Wednesday through Sunday night. The boundary between the short term and the long term is very appropriate today, with the the slow-moving trough exiting our region, and broad high pressure centered offshore building in for an extended stay. Lingering low level moisture is expected to produce early morning stratus in Douglas and Josephine counties, including Roseburg, Cave Junction, and Grants Pass. Otherwise, after another chilly morning, a pronounced warming and drying trend will get underway during Wednesday. This warming will be most significant in southern Curry County with a Chetco effect of downslope warming expected to produce highs in the lower 70s for Brookings on Wednesday, lower 80s on Thursday, and lower 70s into Friday morning before the low level flow turns onshore. The peak of this warming trend at the coast is expected on Thursday. Elsewhere, today`s highs at 20 to 25 degrees below normal, in the lower 50s on the west side and lower 40s on the east side, will seem a distant memory with Wednesday highs near normal at other portions of our coast, and several degrees below normal for inland sites. The warming will be kicked up a notch or two for the remainder of the long term, Thursday through Sunday, with lows above normal, and highs around 10 to 20 degrees above normal. The swing in temperatures from this weekend to next weekend will be in excess of 30 degrees, with the peak of this very strong warming trend expected at inland locations on Saturday. A trough is likely to approach the area on Sunday, Day 7, with only slight cooling. The speed and position of this trough will be the main determinants in whether a risk of showers and thunderstorms develops on Sunday or holds off until Monday/Day 8. && .AVIATION...05/18Z TAFs...The worst conditions today will be along and east of the Cascade Crest as MVFR/IFR conditions can be expected due to snow showers reducing visibility and from lower Ceilings. Klamath Falls and other areas east of the Cascades will have some gusty west winds (up to 30 kt at times). West of the Cascades, expect mostly a mix of VFR/MVFR, with MVFR ceilings/visibilities most likely in heavier showers primarily along the coast and in Douglas County. Area wide, higher terrain will experience obscuration at times. A lessening in shower activity is expected from 00z to 06z, before another front moves onshore during the 06z TAF window. Gusty southerly winds and renewed shower activity should be expected when the front moves through. -Miles && .MARINE...Updated 130 AM Sunday, May 5, 2024...Fresh swell dominates the sea state right now. Seas will become more chaotic as another front moves through late tonight into early Monday morning. The resulting southwest winds should build near, but remain under, gale force. Moderate swell-dominated seas follow Monday into Tuesday. A thermal trough will develop Tuesday afternoon with gusty north winds and steep wind-driven seas, strongest south of Cape Blanco. Wind speeds will peak late Wednesday, but strong northerly winds will persist into Thursday night. The thermal trough will weaken Friday into next weekend. -DW/Miles && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Wind Advisory from 11 AM to 8 PM PDT Monday for ORZ031. CA...Freeze Warning from 2 AM to 9 AM PDT Monday for CAZ080-081. PACIFIC COASTAL WATERS...Small Craft Advisory until 8 PM PDT Monday for PZZ350-356-370-376. && $$ TAD/DW/MCB