Snow Talk

Good morning!  Some light snow is possible later this afternoon and tonight, but “light” is the key word and this shouldn’t amount to much, if any, accumulation across the majority of central Indiana. At most, we’re looking at a few communities that may see a dusting to half an inch type accumulation.  The latest high resolution data shows that we’re on the northern periphery of the storm system that will create all sorts of travel problems for our neighbors to our east and south in the days to come leading up to Thanksgiving.

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Additionally, we’ll keep a close eye on the wind trajectory coming off Lake Michigan Wednesday. It’s looking more and more likely that we’ll have to deal with some lake-enhanced snow showers and embedded heavier squalls here Wednesday as fresh arctic air pours south.  While we’re not expecting any sort of widespread, uniform, accumulation with this, the idea is that a few places (primarily from IND and points north) may see a quick coating to 1″ of snow Wednesday as some of these snow showers and locally heavier (but isolated) squalls drift south into north-central Indiana.  The latest GFS and NAM show the lake Michigan connection well and we’ll keep a close eye on the wind trajectory Wednesday.

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Data Suggests Cold Pattern Keeps On Keepin’ On…

As we approach the all-important holiday travel season, I thought it would be nice to review what some of the data suggests in the long range sense.  While nothing is “set in stone” talking about weather 2-3 weeks out, we feel pretty confident in the overall idea of a colder than normal pattern and one that’s also potentially wintry- from a precipitation perspective.  The specifics with each storm will have to be handled as they come.

Let’s look at some of the data.  BTW, I want to give full credit to the awesome model suite that can be found at Weatherbell Analytics for some of these images.  Be sure to check them out at weather bell.com.

First, we’ll take a look at the Canadian ensembles, centered on the 8-16 day period.  Note the tongue of cold coming out of western Canada, extending southeast and encompassing the Ohio Valley region.  Folks, this is significant cold forecast off the Canadian ensembles as temperatures are suggested to average 5-7 degrees (C) below normal.

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The latest GFS ensembles also suggest widespread colder than normal temperatures over the upcoming couple weeks.  Similar to the Canadian (above), the GFS suggests temperatures average 5-7 degrees celsius below normal.

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Latest European ensemble data suggests a cold look as well, but one that also may feature a day or two above normal (over the next couple weeks). The latest ensemble control run highlights the threat of some bitterly cold arctic air plunging south towards the second week of December (posted below).  We’ll continue to monitor this in the days to come.

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Here’s a look at the latest CFSv2. While it’s in stark contrast to only a couple of weeks ago (in its December forecast), the model is now onboard with most other data in forecasting a colder than normal December for our region.

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It has to be pointed out that all of the cold data is forecast during a time where the three “major” teleconnections really aren’t in the most ideal spots for eastern cold.  Typically, cold lovers across the eastern United States want a negative AO and NAO with a positive PNA. The NAO and AO are forecast to be very “sporadic” over the course of the upcoming 7-10 days while the PNA is forecast to go back negative.  That said, the NAO has the biggest influence on our weather from January through March (we’ve covered this in posts in the archives).  The expansive early season snow and ice pack through western Canada is having it’s say with a couple of early season “brutal” cold shots here (it’s very rare to get this kind of cold so early in the season).  We’ll continue to monitor these teleconnections moving forward for any sort of a more defined signal that may begin to come to fruition.

Speaking of snow and ice cover; look at how much more territory across the Lower 48 is covered with snow and ice compared to this date (November 24th) last year.  Impressive, huh?

November 24, 2012 (11.8% covered in snow)

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November 24, 2013 (37.8% covered in snow)

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As we look closer at the near term, there’s a chance of some light snow moving in Monday evening (not a huge deal, but some light accumulations of a dusting to half an inch are possible).  Scattered snow showers will also blow into central Indiana Wednesday as a reinforcing shot of fresh arctic air blows in prior to Thanksgiving.

In the mid range, both the GFS and European ensembles (below) suggest an “intriguing” look for the first 10 days of December for the potential of a more widespread winter weather maker.  It’s far too early for details, but with arctic air being supplied into a pattern that looks to have a southern branch beginning to flex it’s muscle, we’ll have to remain on our toes as we go into December…  Here’s wishing you a very happy and healthy Thanksgiving, complete with safe travels!

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Permanent link to this article: https://indywx.com/data-suggests-cold-pattern-keeps-on-keepin-on/

A Closer Look At Thanksgiving Week

Today’s model data continues the theme of a southern and eastern storm for the days surrounding Thanksgiving.  We’ll continue to monitor for any potential shift northwest, but as of now, the trend remains for a “suppressed” storm track.  Here’s a look at the individual GFS ensemble members, off today’s 12z run.  Taken at face value, 3 out of 10 members show some light snow in the air.

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For now, the big story still appears to be the unseasonably cold air around for Thanksgiving.  The ECMWF, Canadian, and American models (GFS and NAM) continue to hammer home the idea of a frigid Thanksgiving ahead (relative to the time of year, of course).  I’m not convinced we won’t have to deal with some light snow next week at some point, but for now, the bigger story still appears to be  impressive early season cold, and this cold pattern isn’t going away anytime soon.

The latest European forecast data illustrates this well.  Note each and every day is well below normal, aside from tomorrow (cold air pushes in tomorrow PM).  This is a snap shot of the average temperature (in degrees C) over the upcoming 10 day period.  The blues, greens, and purples showcase the cold, relative to average.

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A Closer Look At Thursday

* A video update was posted late last night and talks about the rain, bitterly cold weekend ahead, and  looks at Thanksgiving.  Scroll below for that update.

Today will feature scattered light to moderate rain, but as noted last night, that rain will grow more widespread tonight.  The latest HRRR simulated radar shows that well.

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High temperatures today are forecast to reach the middle 50s, per the latest HRRR.

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We’re still tracking major league early season arctic air due in here this weekend.  Take a look at just how far below normal these temperatures are come Sunday (shown in degrees celsius).  Wow!  Our forecast high of 24 will be the coldest November day in 13 years and a whopping 25 degrees below normal!  Thanks, as always, to Weatherbell Analytics model suite for this data.

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Permanent link to this article: https://indywx.com/a-closer-look-at-thursday/

Wednesday Evening Video Update: Rain Moving In; Arctic Blast This Weekend

http:/ Tonight’s Video Highlights: We talk rain and amounts for Thursday and Friday. The coldest air of the season and coldest November day in some 13 years is ahead! A…

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Permanent link to this article: https://indywx.com/wednesday-evening-video-update-rain-moving-in-arctic-blast-this-weekend/