• Category Archives Forecast Models
  • Heavy Snow Up North To Close The Work Week; Wintry Weekend…

    Areas of light snow and flurries will impact north-central Indiana Thursday morning, especially north of Indianapolis.  This won’t amount to much and most of our Thursday will be free of snow, along with continued unseasonably cold temperatures.  Speaking of the cold, Indianapolis is running 7° below average, month-to-date.

    Looking ahead, a rather prolonged and significant snow event is setting up shop across northern Indiana.  We forecast snow to begin falling Thursday night before becoming heavy at times Friday.  A tight thermal gradient will aid in the combination of ingredients to produce hefty snowfall across far northern IN and also provide a brief break from the cold, locally, Friday afternoon (forecasting highs into the 40s here).  With that said, if your travels take you north, prepare for significant travel disruptions with the heavy snow.

    A cold front will drop south into central Indiana overnight Friday into Saturday.  At the same time, a couple of disturbances will ride northeast along the front.  This will result in periods of light wintry precipitation across central Indiana over the upcoming weekend.  Initially, this should be rather insignificant with a mix of light rain and perhaps some light sleet or light freezing rain Saturday.

    However, as our airmass becomes progressively colder Saturday night into Sunday things will become more interesting.  At the same time, a final wave of energy will lift northeast, spreading moisture into the colder air mass.  We forecast more widespread wintry precipitation to engulf central Indiana Saturday night into Sunday.  A wintry mix of sleet and snow is possible early on before transitioning to all snow Sunday morning.  A period of accumulating snow is expected Sunday and we’ll fine tune numbers as we move closer.

    Looking further ahead, an active time of things will continue as the battle remains between cold centering itself across the northern Plains into the Lakes and Ohio Valley and resistance from the southeast ridge.  This will continue to lead to a busy period of weather across the region, including storm systems that will come along every couple of days.

    We continue to think things are aligning in a fashion that should result in a significant period of cold developing during the second half of February into March this year.  We note the teleconnections continue to trend in cold directions and the MJO is also rolling along into the colder phases.  We have a long, long ways to go this winter and think some headline events remain on the table as we close the month and open March.  Time will tell.

  • Cold Close To The Week; Snowy Pattern Ahead…

    Arctic air is pressing into the state this evening.  As we type this (just after 6p), wind chill values are already plummeting into the single digits across central Indiana.  Those values will turn even more frigid overnight- dropping to below zero towards midnight.  This is “number-busting” cold as many central Indiana communities will wake up Friday to the single digits (it was only this morning when the majority of model data suggested lower teens).  Obviously, wind chill values will be flat-out bitter, as shown below:

    Arctic high pressure will result in a cold, but dry (and sunny) close to the work week.

    As we move into the weekend, our weather will begin to turn more active.  This will be the first of a series of snow systems over the upcoming 7-10 days.  While this initial event won’t be significant, it’ll get the ball rolling on (at least what we believe will be) another extended stretch of wintry conditions.  We forecast a couple periods of light snow (“light” being the key word) this weekend: Saturday evening and again Sunday evening.  It appears as if the energy will remain very disorganized over the weekend and the result will be light snow accumulations during the Saturday through Sunday period.

    Again, this is only the beginning of a very active pattern; one that will shoot snow systems at us in an “every other day” fashion over the upcoming 7-10 days.  We’ll keep close tabs on last minute adjustments that may be needed with such a pattern. Often times modeling will struggle with the fast-paced northwest flow and models will have to “correct” last minute towards a more significant event.

    Our next snow maker approaches Monday evening into Tuesday.  This would seem to be a more important event and one capable of depositing heavier snow across the general region.  We’ll monitor things this weekend, but the pattern is such that this looks to be more of a central or northern Ohio Valley hit.  Solutions painted of suppression look suspect to us from this distance given the look.

    Additional opportunities for accumulating snow lie ahead, including:

    • Thursday night – Friday
    • Next Saturday – Sunday

    This is all part of the equation we’ve had in thinking that the big story, at least initially, is a very active pattern (snowier version of what we dealt with late December through mid January) before the truly severe cold can get involved mid-and-late February.  On that note, the pattern, as a whole, looks much colder than normal from late February into March this year, as well.

    As for snow, the majority of these events will produce light to moderate amounts, but the active nature of the flow will likely allow things to stack up.  We have no changes to our thinking that the period Feb. 1st through March 6th yields between 15″ and 20″ of snow at IND.  Let’s just remain on guard for the potential of one or two of these systems to potentially lead to heavier totals along the way.

    Make it a great evening!

  • Bet On The Cold…

    During wholesale pattern transitions, operational data will struggle at times, including some wild run-to-run swings.  Earlier this week, the European wanted to put early next week in the lower 50s.  At the same time, the GFS suggested lower single digits.  Precisely, it was a difference of 46° between the two models for a high?!  🙂

    We note the teleconnections (in particular, the EPO) are aligning in a manner conducive for widespread cold.

    The GEFS might be a bit quick on dropping the arctic hammer, but the consistency of the model is impressive.  Meanwhile, the European (even it’s ensemble data) has been much less consistent and has really been struggling the past couple of winters, overall, as a whole.

    While we can argue as to just how cold it’ll get through the early part of February, the overwhelming message is that a prolonged colder than normal pattern will develop during this time period.

    Let’s also keep in mind that the initial cold onslaught is coming in the face of the MJO still rumbling through the warm phases.  We note the European is consistently having to correct towards a more “amped up” MJO- swinging into the cold phases as we approach mid-month.  And it’s mid-February that continues to have us concerned for the potential of truly nasty, severe cold.

    As for snow, it’ll come in this pattern.  Again, don’t get caught up in the operational output, but understand that the pattern over the upcoming 7-10 days favors numerous fast-moving snow systems.  While most of these will be light, we’ll have to keep a close eye on things as the potential exists for one of these waves to spin up a moderate event.

    As we look ahead to Week 2, the potential is there for a more widespread significant phased interior threat prior to the dumping of the bitterly cold air for mid-month.

    As it is, both the GEFS and EPS “mean” paint a bullish signal for piling snow up over the next couple weeks…

  • VIDEO: See Ya’ Later January Thaw…

    Here’s an update on the next couple of weeks. PS: Bo (bottom left in the video towards the beginning ;-)) is our 3rd and youngest Goldendoodle; he was (obviously) trying his best to get in on this evening’s video update…

  • Colder Times Return; Fast-Moving Pattern…

    Upper level energy along with a bit of lake effect enhancement will lead to scattered snow showers late morning through the afternoon and into the early evening. We also note high resolution data picking up on a thin lake effect snow band rotating into the northern ‘burbs after the evening rush.

    Cold high pressure will settle overhead Tuesday and Wednesday and supply a return of dry times, complete with sunshine.  We’ll turn breezy in advance of our next storm system Wednesday.

    That next system will come in the form of a cold front that will settle south across the state Thursday.  Light rain will overspread the region early in the day before mixing with and ending as light snow.  This still doesn’t appear to be a significant event for our region at this time.

    What may be a bigger deal is the event that looms this weekend.  Clouds will increase during the day Saturday and a light mix of rain and snow should develop late Saturday night into Sunday morning before colder air wins out changing all precipitation over to snow.

    We’re getting into a pattern where the northern stream of the jet will dominate over the next 7-10 days (at least). Models will likely struggle handling individual systems and we’ll have to remain on our toes for the potential of last minute shifts with systems in such a pattern.

  • Transition Begins Back To A Prolonged, Sustained Wintry Pattern…

    The January “thaw” has taken hold the past 7-10 days.

    Despite the milder air over the past week, January, as a whole, is still running 4° below average at Indianapolis- a byproduct of just how frigid the first half of the month was.

    While the January thaw has been nice, times are changing and winter sure seems to be reloading for a very active second half.

    Initially, we think it’s the storminess that will be most impressive as a “fight” develops between resistance from southern ridging and a new mean trough pushing southeast.  The end result should be multiple snow and ice makers from the southern Plains into the Ohio Valley and northeast over the upcoming couple of weeks.

    Once we get a snowpack laid down, arctic highs oozing southeast will likely lead to bitterly cold air.  Recall our expectation for this pattern to yield at least (1) night of double-digit below zero lows, but it’s more towards mid-month that we think the severe cold takes hold.

    Teleconnections are lining up and in overall agreement of cold, wintry times returning.

    The Madden-Julian Oscillation (MJO) is forecast to rotate into the colder phase 8 as we rumble from early to mid February.  Given the amplitude of the MJO, it should continue to rumble right through the cold phases of 1,2, and 3.

    All of these moving pieces that lead up to extended periods of cold, wintry conditions are part of a bigger outcome low solar, easterly QBO winters deal up.  What we should experience with this setup is a 6-7 week period of wintry conditions, including times of severe cold.  It appears to be a snowier version of what we went through late-December through mid-January.  Hang in there, spring will come…eventually.