Friday to kick off a very stormy weekend

Weather Blog

PORTLAND, Ore. (KOIN) – In the next 24 hours, we’ll make a quick transition from summer to fall.

Morning temperatures on Friday will start in the low 50s with daytime highs reaching the mid-70s. But it’s not so much the temperatures that will feel all that different — it’s the rain, gusty wind and possible thunderstorms.

You can relax for the first part of the day. Expect mostly cloudy skies and a southerly flow. Rain is not expected to arrive in Portland until the evening hours. It may be light rain initially around 5 or 6 p.m. with the arrival of a warm front. That rain intensity increases by late tonight.

Once a cold front passes, our chance of thunderstorms increases across the Willamette Valley and coast midday Saturday. Forecast rain totals could measure up to 1.5 to 2 inches by the end of the weekend.

The atmospheric river

NCEP Integrated Water Vapor Transport (IVT) and Integrated Water Vapor (IWV) Analyses and Forecasts
From left to right: Analysis to a 24 hour forecast of an atmospheric river.

Interesting to note, we already began to feel the change from summer to fall on Thursday morning. Hillsboro Airport dropped to a record low of 37 degrees. While that’s only 1 degree below the 1987 record of 38, it’s still more than 10 below normal.

Portland International Airport PDX did not break any records but did drop to 45. The last time our low temp was that cold was back in the middle of May (May 21: 46º). The normal low this time of year is 54.

Gale warning

GALE WARNING NOW IN EFFECT FROM 8 AM FRIDAY TO 2 AM PDT SATURDAY…

* WHAT…South winds 20 to 30 kt with gusts up to 35 kt and seas 7 to 11 ft at 10 seconds expected.

* WHERE…Waters from Cape Shoalwater WA to Cascade Head OR from 10 to 60 NM and Coastal waters from Cape Shoalwater WA to Cascade Head OR out 10 NM.

* WHEN…From 8 AM Friday to 2 AM PDT Saturday.

* IMPACTS…Strong winds will cause hazardous seas which could capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS… Mariners should alter plans to avoid these hazardous conditions. Remain in port, seek safe harbor, alter course, and/or secure the vessel for severe conditions.

https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=pqr&wwa=gale%20warning

Wind advisory

WIND ADVISORY IN EFFECT FROM NOON TO 11 PM PDT SATURDAY…

* WHAT…Southwest winds 25 to 40 mph with gusts up to 50 mph expected.

* WHERE…In California, Modoc County, including highways 299, 395, the cities of Alturas, Canby and Willow Creek. In Oregon, Northern and Eastern Klamath County and Western Lake County and Central and Eastern Lake County. This includes the cities of Lakeview, Valley Falls, and portions of highways 140 east of Bly, 395 and highway 31 between Summer Lake and Lakeview.

* WHEN…From noon to 11 PM PDT Saturday.

* IMPACTS…Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result.

* ADDITIONAL DETAILS…Gusty winds could also lead to enhanced fire behavior on existing fires.

* View the hazard area in detail at https://www.wrh.noaa.gov/map/?wfo=mfr

PRECAUTIONARY/PREPAREDNESS ACTIONS… Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects.

https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=pqr&wwa=wind%20advisory

It’s a sharp turn from fire weather danger to wet and windy conditions.

RED FLAG WARNING IN EFFECT FROM 1 PM MDT /NOON PDT/ TO 9 PM MDT /8 PM PDT/ SATURDAY FOR GUSTY WINDS AND LOW RELATIVE HUMIDITIES FOR OWYHEE MOUNTAINS…WESTERN TWIN FALLS BLM… SOUTHERN HIGHLANDS…BURNS BLM AND VALE BLM…WHICH ARE FIRE WEATHER ZONES 423…424…426…636 AND 637…

The National Weather Service in Boise has issued a Red Flag Warning, which is in effect from 1 PM MDT /noon PDT/ to 9 PM MDT /8 PM PDT/ Saturday.

* WINDS…Gusts 30 to 40 mph.

* RELATIVE HUMIDITY…8 to 15 percent. PRECAUTIONARY/PREPAREDNESS ACTIONS… A Red Flag Warning means that critical fire weather conditions are either occurring now, or will occur shortly.

https://forecast.weather.gov/showsigwx.php?warnzone=ORZ061&warncounty=ORC025&firewxzone=ORZ636&local_place1=26%20Miles%20WSW%20Hines%20OR&product1=Red+Flag+Warning&lat=43.4042&lon=-119.5434#.YUREWJ5KhE4

Copyright 2021 Nexstar Media Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Twitter News Widget

Trending Stories