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
391 FXUS66 KMFR 092132 CCA AFDMFR Area Forecast Discussion...CORRECTED National Weather Service Medford OR 232 PM PDT Tue Jul 9 2024 .DISCUSSION...Satellite image shows clear skies over most of the forecast area. The exception is for marine stratus along the coast from Cape Blanco south and some cumulus build ups along the Cascades and higher terrain east of the Cascades. Smoke from the Shelly and Salt Creek fires are mainly concentrated in the vicinity of these fires and will be the case for the next hour, then once the typical northwest flow kicks in, the smoke from the Salt Creek fire will get transported southeast towards Klamath Falls, but not should not be in Klamath Falls proper. Also the smoke from the Shelly Fire will also get pushed southeast late this afternoon and evening. In the meantime, dry and hot weather will continue through the end of the week. Afternoon temperatures will be at their highest today for most inland locations, with a slow downward trend tomorrow through Friday, although they will still be near or at triple digits for most interior west side valley locations and low to mid 90s east of the Cascades. The one notable improvement will be cooler overnight lows the latter part of the week. However. overnight lows tonight and Wednesday night will be similar to this morning (maybe a degree or two lower). The weather situation this weekend will need to be watched carefully. This will especially be the case along and east of the Cascades and northern California. The upper ridge that`s been over the area for the past week is expected to shift to the four corners this weekend. At the same time an upper low will develop off the California coast Saturday. This will result in a southerly flow pushing into our area and could tap into a bit of monsoonal moisture. The amount of moisture is limited, but the pattern that`s setting up is a bit concerning in that it typically results in an elevated risk for isolated thunderstorms east of the Cascades and northern California. For Saturday, the biggest risk for isolated storms should be mainly confined to Lake and southeast Modoc County in the afternoon and evening hours. This is by no means a slam dunk, but at the same time it cannot be discounted. Sunday, the situation should be more favorable for isolated storms. Some evidence supports most of the action could end up northeast of our forecast area. However, there` still sufficient evidence to suggest the threat at risk for isolated storms Sunday afternoon and Sunday evening will be in Lake, eastern Klamath and eastern Modoc County. Once we get by this weekend, a dry and stable southwest flow will return with any threat for storms ending, but afternoon temperatures will still remain above normal for the interior. -Petrucelli && .AVIATION...09/18Z TAFS...Along the coast and just offshore, LIFR and IFR in fog and low clouds will linger today south of Cape Blanco, including at Brookings (KBOK). Then IFR and LIFR will expand to a larger area along the coast this evening through Wednesday morning, including at North Bend (KOTH). VFR conditions will continue inland through the TAF period. However, areas of wildfire smoke in the vicinity of the Salt Creek, Shelly and Bogus fires could cause MVFR visibility. Even local IFR/LIFR is possible (but isolated and in very close proximity to the fires themselves). Local wind gusts of 20-25 kt can be expected at most terminals later this afternoon and early this evening. -Spilde/CC && .MARINE...Updated 200 PM Tuesday, July 9th, 2024...A thermal trough will strengthen late today through Thursday resulting in increasing north winds and elevated seas. Small Craft Advisory conditions are expected to develop this evening through Thursday morning for areas south of Cape Blanco, with moderate north winds and steep wind driven seas. Winds and seas increase Wednesday afternoon into Thursday with gales and very steep seas expected from Gold Beach south beginning Wednesday evening then for areas south of Cape Blanco Thursday afternoon and night. North of Cape Blanco, winds will be weaker today but increase Wednesday evening and Thursday with gusty, north winds and steep seas likely. Moderate to strong north winds and steep to very steep seas may linger on Friday. Then winds and seas are expected to gradually lower Saturday and Sunday. -CC && .FIRE WEATHER... ...Elevated to critical fire weather conditions possible all week... Our trend of hot, breezy, low humidities, and occasional unstable afternoon conditions will persist through this weekend, and this will lead to elevated to critical fire weather conditions. Additionally, we have a chance for thunderstorms this weekend across the eastside of the forecast area. Wind speeds are not too crazy this week, but they certainly will be on the breezy side around 10-20 mph. Single digit RH values are also forecast this week during the afternoon hours across the eastside and some isolated westside valleys like Northern California. These factors, on top of this prolonged drying stretch will result in elevated to critical fire weather conditions nearly every day this week. There may be a couple hours here and there when critical thresholds are met, but this afternoon and tomorrow afternoon may fall just short of actually reaching those critical thresholds. While no official warnings are out now, it will be very borderline today and tomorrow afternoon for fire weather conditions, so the threat is there even if we aren`t hitting "criteria". Conditions worsen as the week progresses, and we will likely see Red Flag Warnings coming to fruition as early as Thursday (if conditions do not change sooner). There is some relief from this heat by Wed/Thurs with a slight cool down, but the reality is that temperatures are still going to be on the warm side. Much of the area hasn`t received much rainfall either, so fuels are only going to worsen as this prolong dry stretch continues with above normal temperatures. The heat is obviously of importance for those outside fighting the fires as well. For the thunderstorm potential, it should be noted that the trend has increased over the last 48 hours for both Saturday and Sunday. A lot will depend on how a ridge of high pressure sets up over the Four Corners region because this will directly impact our moisture source. There is about a 10-20 percent chance for isolated thunderstorms both Saturday and Sunday. Of these days, Sunday currently looks like the best shot for thunderstorms, and this will be primarily over the eastside of the forecast area. -Guerrero && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Excessive Heat Warning until 9 PM PDT Wednesday for ORZ023>026. Heat Advisory until 9 PM PDT Wednesday for ORZ029>031. CA...Excessive Heat Warning until 9 PM PDT Wednesday for CAZ080>082. Heat Advisory until 9 PM PDT Wednesday for CAZ083>085. PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Thursday for PZZ356-376. Gale Watch from late Wednesday night through late Thursday night for PZZ356-376. && $$