Get ready…LOTS of changes in the weather ahead over the next 48 hours or so. Today brings us a taste of late March, with cool and breezy conditions throughout the day. The wind will be strongest around midday, with gusts 15-20 mph:
Temperatures will run about 10-15 degrees below normal throughout the afternoon:
The coolest temperatures will be in eastern Middle Tennessee, where the cloud cover will be thickest, and where you have the best chance of showers through midday:
It will be mostly clear and almost-chilly tonight — lows Friday morning will drop into the 40s, with some 30s outside of Nashville:
Friday morning’s record low in Nashville is 35 degrees, so at least we’ll stay above that. The big turnaround in our temperatures starts to kick in Friday afternoon, when we’ll warm up to the low to mid 70s:
So we’ll go from “within shouting distance” of a record low Friday morning, to within five degrees of record highs Saturday and Sunday (89 and 90 are the records, respectively). What in the world is going on? The explanation lies with the upper-level wind pattern — the jet stream (or “storm track”) has been in a very amplified pattern this week. That means that instead of following a wavy pattern from west-to-east across the country, part of the jet stream has been pushed way up into Canada, while part of it has dipped way down into the southeastern United States:
That pattern is called an Omega Block (because it resembles the Greek letter omega: Ω), and it’s why temperatures in Canada have been 30 degrees above average — more on that in the nerd-links below. Omega blocks are stubborn, but they don’t last forever, and this one will start breaking down tomorrow. That will allow the warm air that’s been trapped to our west to start leaking towards us on Friday, and rushing into the Midstate this weekend:
The warmth will continue into next week, although temperatures will retreat slightly as our rain chances increase. The unsettled weather pattern kicks in late Monday, and it looks like it will stick around most of next week, as little ripples in the upper levels of the atmosphere kick off intermittent showers and thunderstorms:
There isn’t a particular signal toward a high probability of severe weather on any given day, but it’s early May, so we’ll keep a close eye on the severe possibilities.
Lots of weather stuff today, along with some other geekiness…
- Researchers have created the first high-resolution cloud maps for the entire globe.
- More about Omega blocks, and the Fort McMurray fire in Alberta.
- This is the most-detailed update I’ve seen about what’s been lost in the fire, and what’s still to come.
- The specific weather pattern (the aforementioned Omega block) is largely responsible for the Alberta wildfire, but climate change has a lot to do with the frequency of that weather pattern and the overall situation.
- Smoke from the Canadian fire is blowing southward into the United States.
- Decreasing levels of Arctic sea ice may result in more blizzards in the eastern United States.
- Skies over our neck of the woods should be clear enough for you to catch a glimpse of the Eta Aquarid meteor shower late tonight.
- Pluto’s interaction with the solar wind is unique.
- Way waaaaaay out there in space, there’s a star that looks like our own Sun, but has completely different internal dynamics.
- I thought that “direwolves” were completely fictional creatures within the world of Game Of Thrones, but it turns out they once were real animals.
- The science behind Hitler’s atomic bomb program — and how it was stopped.