It’s October first. It’s not news that there are areas of snow above 10,000 feet in the mountains or 90ºF heat across the Southeast but what is news is that those two different air masses are battling for dominance in a way that you can literally see.
On this GOES16 Satellite imagery, you can see the battlegrounds. They extend from New Mexico all the way to Michigan. The airmass over the northwest is a mostly cold one. It has snow, ice, high winds and some pretty dry air in places. The airmass over the southeast is a relatively hot one. It has sunshine, fair-weather clouds, and a decent amount of humidity.
|2M Temperatures just before Lunchtime on 10/1/19|
Talk about a visual. October is a typical battle month in terms of the weather. This isn’t completely abnormal but it is the first of the season and it is doing it in a dramatic way. The southeast has been basking under a ridge of high pressure making temperatures soar and drying out the soil. So this stubborn high pressure is to blame for the lack of cold air further south and that spells bad news for people in the northwest if they don’t like cold or snow. The anomalously strong and cold system that just dumped 4 feet of snow on Montana is surprisingly not strong enough to make the high pressure off to the south and east move. So both systems are sitting there arm wrestling but they’re both not winning. That’s not good news for the residents that are sitting “under the arms.”
|National Alert Map 10/1/19|
Right under the arms of the parent arm wrestlers in our atmosphere, flooding is occurring. Essentially, the air masses are colliding and forcing air together with a result of rain. The atmosphere is getting wrung out right now and people from El Paso, TX to Lansing, MI are feeling that effect. How much rain are they going to see?
|Rainfall totals through Thursday, October 3, 2019|
You can almost pick out the circulation that is the high pressure over the southeast. Imaging the high pressure sitting right over Tennessee. High pressure spins clockwise so the rain that is falling in Texas, New Mexico, Oklahoma and Kansas is very tropical. The high pressure is scooping up moisture from the Atlantic, Gulf of Mexico and the Caribbean and depositing it along the front lines of the battle zone. Pretty clearly seen here.
While this battle won’t last forever, the near term effects are already underway. Eventually, winter will win out but until then, just know that you are experiencing this battle no matter where you are in the country.
~Rain or shine
I’m Andy Stein