Major weather pattern change is expected across the Pacific Northwest and Western United States starting Friday, October 21, until the weekend, bringing inclement weather conditions and below-average temperatures. The shift from warm to cold weather is due to a strong cold front that will move from the Northwest to the West over the weekend, causing heavy mountain snowfall and gusty winds regionwide.

Major cities like Los Angeles, California; Seattle, Washington; and Portland, Oregon could experience a sudden or gradual drop in temperatures. As the end of the fall season and start of the winter approaches, meteorologists anticipate the change in weather pattern. Long-term temperatures beyond this coming weekend are still uncertain. However, rain showers and snowfall are possible during this period.

Major Weather Pattern Change

weather forecast
(Photo : Photo by RICHARD BOUHET/AFP via Getty Images)

The National Weather Service (NWS) - Weather Prediction Center (WPC) issued a new short-range forecast at 3:50 p.m. EDT (local time) on Thursday, October 20, stating that that increased precipitation chances and decreased temperatures in the Western US is possible this weekend. In addition, other parts of the North American nation will experience different weather conditions.

For instance, the NWS - WPC said there will be above-normal warmth in the Central US and critical fire weather conditions in Montana and Wyoming. This means that the cooling of the West America will also warm up the Central US and the East Coast. This comes after a large portion of the Eastern Seaboard were placed under freeze warnings or frost advisories in recent days.

Also Read: Parts of Northeast Experiences Snow Amid Active Weather Pattern

Low Pressure System

The major weather pattern change nationwide is being caused by a low-pressure system which pushes a cold front southeast, resulting elevated rainfall chances and cooling temperatures this weekend across the West Coast.

The NWS also predicted the cold weather will eventually expand across the Northwest and northern Rockies on Saturday, further pushing towards the Intermountain West and Plains on Sunday, October 23. The increased precipitation could also serve as a relief to existing wildfires and decrease fire danger in some areas.

Early Week Cold Snap

The US weather agency acknowledged the cold snap in the Central and Eastern US earlier this week, which Nature World News also covered. Over 75 Americans were placed under frost or freeze alerts when the cold weather moved further into the Southern US, according to ABC News on Thursday, October 20.

The same cold weather forecast was issued in the preceding days when over 100 million Americans were placed under freeze warnings, freeze watches, and frost advisories for most parts of the Eastern US, according to CNN.

Yet, temperatures are getting warmer again across the region this weekend, where high temperatures could reach as high as 20 to 25 degrees above normal into the upper 70s and lower 80s in some areas of the Midwest.

The Eastern US will feel the warming trend with temperatures returning to slightly above normal by Sunday.

The US is currently in its autumn or fall season, which started in late September and expected to last before late December, wherein its winter season will kick in.

Related Article: As Spring Marches in, Noticeable Changes in Weather Patterns May Follow in the US