Here is my weekly weather quiz question for the last time. “What is a “Roll Cloud?” Here is the correct answer. A Roll Cloud is a low, horizontal tube-shaped arcus cloud associated with a thunderstorm gust front (or sometimes with a cold front). Roll clouds are relatively rare; they are completely detached from the thunderstorm base or other cloud features, thus differentiating them from the more familiar shelf clouds. Roll clouds usually appear to be “rolling” about a horizontal axis, but should not be confused with funnel clouds.
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An Upper Level High Pressure Ridge (“Arch” shape) starts heating us up. The graphics for days 1-3 show a frontal system offshore headed to the Pacific Northwest today then pushing through by tonight. The graphics for days 3-7 Tuesday through Saturday show a cold front that will be pushing through the Pacific Northwest Tuesday and Tuesday night.
ADVISORIES:
- NONE AT THIS TIME.
HEALTH ADVISORIES:
- A PERMANENT HEALTH ADVISORY REMAINS IN EFFECT FOR THE SOUTH UMPQUA RIVER BAR. POOLS IN THE BEDROCK ALONG THE RIVERS EDGE ARE KNOWN TO DEVELOP BLUE-GREEN ALGAE (CYANOBACTERIAL) BLOOMS THAT CAN BE HARMFUL TO PETS AND PEOPLE IF ACCIDENTAL INGESTION OCCURS. SIGNS HAVE BEEN POSTED ALONG SEVERAL ACCESS AREAS ALONG THE RIVER.
Forecast for the Southern and lower Mid Willamette Valley including Eugene-Springfield and Albany-Corvallis:
- A mix of clouds and sun and a bit cooler today, mostly cloudy tonight,
- Sunny and a bit cooler Sunday, mostly clear at night,
- Sunny and a bit warmer Monday, then clear Monday night.
- high 82-78 warming to 80 Monday lows 53-49.
- Sunny Tuesday, mostly clear Tuesday night,
- Sunny and a bit cooler Wednesday, clear Wednesday night,
- Sunny and a bit warmer Thursday, mostly clear in the evening, partly cloudy Thursday night,
- Then mostly sunny and a bit cooler Friday.
- highs 80-75 warming to 76 Thursday cooling to 72 Friday lows 49-46. (seasonal averages high 72 low 47)
Forecast for the Umpqua Valley including Roseburg:
- Mostly cloudy start, partly cloudy and a bit cooler this afternoon, partly cloudy tonight,
- Sunny and a bit cooler Sunday, mostly clear at night,
- Sunny and a bit warmer Monday, then clear Monday night.
- highs 83-82 warming to 85 Monday lows 56-54 warming back to 56 Monday night.
- Sunny Tuesday, mostly clear Tuesday night,
- Mostly sunny and a bit cooler Wednesday, clear at night,
- Mostly sunny Thursday, mostly clear Thursday night,
- Some AM clouds, then sunny and a bit cooler Friday afternoon.
- highs 85-76 lows 54-52. (seasonal average high 75 low 51)
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Forecast for The South Oregon Coast Including Coos Bay and North Bend:
- Patchy AM coastal fog, mostly cloudy and a bit warmer this afternoon, mostly cloudy this evening, partly cloudy late tonight,
- Some AM clouds, sunny and a bit cooler Sunday afternoon, partly cloudy at night with patchy coastal fog late,
- Mostly sunny and a bit warmer Monday, then mostly clear Monday night.
- highs 68-66 warming to 68 Monday lows near 49.
- Mostly sunny and a bit warmer Tuesday, mostly clear in the evening, partly cloudy with late Tuesday night,
- Mostly sunny and a bit cooler Wednesday afternoon, mostly clear at night,
- Sunny and a bit cooler Thursday, partly cloudy Thursday night,
- Then partly cloudy and a bit cooler Friday.
- highs 68-64 lows near 48. (seasonal average high 63 low 51)
Forecast for the Northern Oregon Cascades including the Cascades in Lane County:
- A mix of clouds and sun and a bit cooler with a slight (20% ) chance of showers this afternoon, mostly cloudy with a (40%) chance of showers tonight,
- Mostly sunny and a bit cooler with a slight (20%) chance of showers Sunday, mostly clear at night,
- Sunny and a bit warmer Monday, then mostly clear Monday night.
- snow level above 8,000 ft. today through Sunday, free air freezing level 13,000 ft. Sunday night, 14,000 ft. Monday, then 15,000 ft. Monday night.
- highs 72-66 warming back to 72 Monday lows 48-43 warming to 46 Monday night.
- Sunny and a bit cooler Tuesday, mostly clear Tuesday night,
- Sunny and a bit cooler Wednesday, clear at night,
- Sunny and a bit warmer Thursday, mostly clear in the evening, partly cloudy late Thursday night,
- Then mostly sunny and cooler Friday.
- free air freezing level 14,000 ft. Tuesday through Thursday night, then 12,000 ft. Friday.
- highs 70-67 warming to 70 Tuesday cooling to 59 Wednesday lows 42-40.