Let's start things off on a postive note. :) Monday looks GREAT. It may be a long time before we have another day this nice....so I advise that you make plans to get outside. Expect partly to mostly sunny skies with highs shooting into the 60s, along with breezy southerly winds. This warm-up will be in response to a storm system developing over the Plains which will deliver a ton of snow to the upper Midwest. So while we will be soaking up the warmth tomorrow, folks across upper Midwest will be breaking out the snow shovels for the first time this season. Check out the winter storm warnings (pink) and winter weather advisories (purple) that stretch from Montana to the upper peninsula of Michigan. Some areas in the pink are forecast to receive over a foot of snow!
This storm system arrives Tuesday bringing a band of showers through the state. The rain does not look heavy and thunderstorms appear unlikely.
Behind this storm system, arctic air will come pouring in, with the core of it arriving Thursday and Friday. It is going to get really cold folks. Highs on Thursday and Friday will struggle to even reach the middle 30s, with parts of northern Indiana not even getting above freezing!! Again, we are talking about HIGHS here!!! Actual night-time lows will get down into the lower 20s, with upper teens possible on any night that sees clear skies. Here are the 7am 850 mb temp snapshots from the European model for Wednesday, Thursday and Friday.
Once the cold arrives, don't expect it to go anywhere too quickly. Let's take a look at a couple teleconnections. First, I will show you the NAO forecast. The NAO tells us the amount of blocking present. If you have a negative NAO, expect a more amplified jet stream pattern across the country. If it is in positive territory, this means a more zonal, progressive pattern. As you can see below, the NAO is going negative during this period.
Now let's look at the PNA. This basically indicates the jet stream configuration. The PNA is going positive. This means we can expect a trough in the east and a ridge in the west.
Based on these teleconections and the overall pattern, things could get interesting next weekend as the models are indicating some sort of storm system potentially passing through the Ohio Valley. Instead of looking at the models, let's look at the big picture. The pattern supports an arctic blast moving in this week. The pattern supports some sort of storm system developing to our southwest. As this storm pushes to the east next weekend, the blocking pattern should allow it to curve north as it heads toward the east coast instead of simply heading out to sea. However, there are still many smaller details that are in question. For example how deep will the cold air be over the Ohio Valley when this storm moves through?? The bottom line that there is potential for some measurable snow in sections of the Ohio Valley later next weekend...however this is far from being etched in stone!
Old Man Winter is getting an early start this year!! Thanks for reading and take care.
