Massive Winter Storm Next Week
The big question is will it produce snow in Kentuckiana! Social media is on fire with people talking about a huge snow storm for us next week. With Twitter, Facebook and blogging, people often post the raw data and this starts a feeding frenzy on snow! Monday and Tuesday morning the raw GFS and Euro data was showing MASSIVE amounts of snow over Kentuckiana. We're talking between 10 to 15 inches! But that is not an accurate picture of reality.
Analyzing the Data
Both the GFS and Euro have been trending warmer and farther north with the storm track (along and north of the Ohio River). I would expect that to be true with it coming out of TX and climo history would support a more northerly track.
Because both the GFS and Euro are similar we will take a look at the GFS.
The first map is the Surface 1000-500mb thickness. Notice the 540 thickness line (snow-line) is well north of us in northern IL and IN. That means rain for us.
The 850mb Height/Temp chart for Tuesday morning also supports rain. Our 850 temp is sitting around 3.6 degrees Celsius (0 Celsius is freezing). I like to see around -3 to -5 to be confident about snow.
By Tuesday evening the 540 thickness line is north of IN and the GFS is showing heavy rain over us. Both the GFS and Euro showing 3 inches or more rain falling Tuesday! If we do see this much rain flooding and flash flooding could be an issue by Tuesday evening.
I do think areas from Indianapolis north have a very real chance of a Major Winter Storm with some huge snow totals.
850mb winds (about a mile above the ground) are extremely strong out of the southwest... 80+mph! That means strong warm air addvection. Our 850 temps climb 7 degrees from 3.6 to 10.6 Celsius (that's 51 Fahrenheight)!
Will We See Snow on the Backside of the Storm...?
I think our best chance of seeing snow will be Wednesday on the backside of the storm as the cold air pushes into Kentuckiana. As always the question is... How much moisture will there be left to produce some wrap-around snow?
Wednesday morning the 540 line is well south of the Metro and the 850 temp is around -6 celsius. This would support snow for us and the GFS is still showing quite a bit of moisture over us, but this system is moving fast and is already in NY/PA. So, I think the amount of wrap-around moisture may be a bit overdone...
At this point in time it is just to soon to be throwing around snow totals as a lot could happen between now and next Wednesday!
850mb Temp Wednesday morning around -6 celsius... Cold enough for snow
By Wednesday evening the Low is off the coast of Maine and any leftover moisture is pushing into eastern Kentucky.
850 Temps are around -9 celsius and the 540 line is sitting in TN.
My Final Thoughts
Let me say again... A lot could happen between now and next Tuesday/Wednesday. If this storm system tracks 200-300 miles farther south that would put us in the bull's-eye for heavy snow!
I think we need to be concerned about the flooding potential on Tuesday and the chance for wrap-around snow on Wednesday.