National Hurricane Center: Atlantic Basin Activity
🌀 An increase in tropical activity across the Atlantic Basin could help ring in a Fall chill across parts of the eastern United States by the middle of October.  
The Atlantic and Pacific Basins are full of life with tropical activity! Numerous storms in both basins will ultimately control the sensible weather over North America as we head into October.

I have been on record stating that around October 12, we will reach the end game of any “summer-like” weather for the Midwest and Ohio Valley as a tropical entity merges with a deep, mid latitude trough on or near the East Coast of the United States. This wave is emerging off of Africa now and can be seen as the far right X in the graphic above. With today being September 27th, add about 15 days from now, we sit at October 12th. I am well aware that this may be completely incorrect as it is tough to pin down shortwave energy this far out, but on the otherhand, this is what makes weather prediction fun! Now judging by the current pattern, and considering what is happening in the Pacific Ocean, I believe I am on the right track.



Typhoon Mindulle is getting entrained into the Polar Westerlies and will likely send down a sizable trough by the beginning of next week. This should lead to a cool shot in the west and downstream amplification for the central and eastern United States. Much like the Atlantic, the Pacific also has a wave cooking behind Typhoon Mindulle. Like its predecessor, this wave will get pulled into the Polar Westerlies and race towards the Gulf of Alaska about 5 days from now, leading to even greater amplification. We should see this particular wave evolve between October 8-10.

Using general knowledge that this injection of energy will bring, it would bring a low into the United States around October 10, and deepen as it heads eastward. At the same time, this presumed Tropical wave near Africa will draw closer to the eastern seaboard of the United States. The two systems could interact with each other, leading to a solid chance of meaningful amplification in the Midwest, Ohio Valley, and Northeast, with a more pronounced and powerful cold shot. Thus my reasoning for and end to “summer like” weather and the potential for first frosts and freezes for some of the areas mentioned above. 

Let’s see how this all comes together!

⭐ Forecast Provided By: Meteorologist Joshua Ketchen

  • 🌡 Winter Snowfall Forecast
    Show and hide layers
    🌡 The 2020/21 SWC Winter Snowfall Forecast illuminates a wintry picture over a large portion of America. A La Nina favored large-scale pattern with upper-level ridging in the west and troughing in the east was considered in developing this forecast. Other influences, from the Arctic to the North Atlantic, could play a major role on how storm systems progress across the country.
  • ❄ The SWC Winter Forecast has been released for the 2020-21 Season. Meteorological Winter starts on December 1, 2020 with the U.S. experiencing warmer than normal weather conditions. Our forecasters break down the details of how Winter will play out in your area.
  • ⚠️ U.S Advisory Layers
    SWC Weather Advisory Layers
    ⚠️ Click on real-time watch, warning, and advisory polygons for critical weather information. Allow the SWC location feature to plot your location on the map. Expand the map and visit all SWC Weather Layers.
  • 🧊 As Winter Weather impacts become more frequent across America, it's important to brush up on the basics. Let's review how you can prepare yourself and your family for the worst of Old Man Winter!
    📦 Pack an Emergency Supply Kit.
    📱 Charge all Communication devices.
    🚗 Winterize all family vehicles.
    📖 Get up-to-date weather reports.
    🙌 Share your travel plans with others.
    🛣 Monitor road conditions.
  • 📡 View the latest Goes-16 Visible Satellite image of the United States. This image will update every 5 minutes.
  • 🔥 As La Nina continues to control the overall pattern across the Western U.S., dry conditions are prevailing across Arizona, Utah, and New Mexico. These conditions are forecasted to continue through Winter 2020/21.