October, month-to-date, has been nothing short of a blow torch. Officially, IND is running +9° through the 11th.
In coffee shops and my travels around the great state of Indiana, I’ve overheard lots of talk centered on because October has been so warm, another lackluster snow season awaits. Let us remind you that the infamous snow season of ’13-’14 featured a very warm first half of October.
The upcoming 7-10 days will feature more of a transitional period of weather that we’ve come to know and love around these parts. Warmth will spread northeast this weekend ahead of an approaching cold front (around 80° Saturday) before falling temperatures Sunday afternoon behind the frontal passage. The chilliest air so far this season will descend upon the region early next week. That said, the chill won’t hold and another surge of above normal warmth will spread northeast by the latter parts of next week.
A more significant pattern change appears dialed up prior to Halloween and this is one that seems suited to lead to more prolonged and significant cold to wrap up the month and head on into November. Notice the evolution of things from October 21st to the 25th, courtesy of the GEFS off the fantastic tropicaltidbits.com. Other model data is in general agreement, leading to a rather high confidence level for this time period.
It should also be noted that analog data and research also would lean heavily in the cold direction to wrap up October and these findings also favor a chilly November… More on that later! Speaking of later, an updated 7-day will be posted this evening. Make it a great day!
After the past week to ten days, that frigid open to the month seems like forever ago! The past 7-10 days has featured a significant January thaw, and temperatures now, MTD, are warmer than average across the Ohio Valley. Warmest anomalies can be found across the southeast region.
That said, the pattern is shifting back to winter for the last week of the month and while the duration, longer-term, can be argued, the next 2-3 weeks appear to offer an opportunity to play “catch up” in both the snow and cold departments. Note the developing eastern troughiness. This will bring colder air back into the east as we close January and open February. The GFS ensembles, courtesy of Tropicaltidbits.com, also develops an interesting “blocky” look towards the end of the period in Week 2. Should this verify, it would lead to a better chance of the cold, active pattern locking in.
Thinking here at IndyWx.com believes the European is likely rushing the warmer central look. Time will tell…
Speaking of warmth, 2016 has been a very warm year.
(The cold of 2014 seems so long ago…)
Back to present. We’ve targeted the middle part of November to finally beginning “bucking” the recent warm trend. This won’t happen overnight and will be a battle of back and forth, initially. Thus, the “step-down” label. To be clear, November, as a whole, will finish much warmer than average. It’s virtually impossible to counter the incredibly warm start. That said, we do anticipate “jabs” of colder air working in here over the next couple weeks. For instance, this weekend will feature lows in the 20s for most and highs not making it out of the 40s Saturday afternoon. (The average low and high at IND Saturday are 37 and 54).
When we look at the AAM forecast (above), we note the westerlies may begin to slow (indicative of the negative values) in the 8-10 day period. This is crucial and, simply put, has to happen for the pattern to begin shifting into more of a position to allow sustained cold to enter the equation. We want to reiterate that this, in and of itself, doesn’t create the cold, but instead allows the pattern to begin shifting away from the Nino-like (warm) regime into more of a La Nina pattern, as a whole. – Hey, you have to start somewhere.
Additionally, the EPO is forecast negative off the GEFS and EPS. (Images courtesy of Weatherbell.com).
Again, this is a cold signal. (Image courtesy of Madusweather.com).
The ensemble data is also beginning to key-in on higher heights (blocking) developing over the top. Notice the significant changes in the overall look to the pattern between now and days 11-16. (Images courtesy of Weatherbell.com).
In summary, and in the face of *most* seasonal data that is screaming warm, warm, warm, we still don’t have any significant changes to our overall thinking of “step-down” mid-November giving way to more sustained wintry-like conditions in the overall sense from the Thanksgiving-Christmas period. Time will tell and only the Good Lord knows what the future holds, but we’ve done far too much work and research to throw the “game plan” in the trash before the game even begins…
Tuesday will remain rain-free across the region, along with pleasant temperatures and humidity levels (mid 70s after a low in the lower 50s).
Rainfall amounts don’t look particularly impressive; generally 0.10″-0.25″ during the Wednesday night-Thursday morning time frame.
The cool air flowing in behind the front is impressive though. In fact, highs both Thursday and Friday will likely only reach the lower 60s (if that).
Despite the chilly air that will be with us to wrap up the work week, ensemble data is in excellent agreement on a significant warmer than average regime developing under a big eastern ridge in the 6-10 day. This will likely promote highs into the lower 80s next week for a few days. Impressive, no doubt, considering we’ll be rumbling through the second half of October by that point.
