Category: Forecast Models

A Word On The Longer Range; Steady As She Goes…

We wanted to touch briefly on the longer range weather pattern as we’ve been answering questions this weekend out there concerning what lies ahead. Ultimately, the good Lord above is the only one who knows tomorrow and this idea we have very well may be the wrong one. However; we still see a lot of winter in this weather pattern. The combination of below average snowfall to date, combined with milder air the past 24 hours has led some winter lovers into a panic. Despite the past 24 hours, let’s remember where we are for the month of January through the first half:

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Now let’s compare this to the infamous January 2014:

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So far, this January the cold is more widespread across the nation. Additionally, through the first half of January, IND is actually running colder than last January. Many remember the brutal cold following the major winter storm early last January. Let’s also remember that a few days after that snow and cold we were dealing with much milder air and rain- a bonafide January thaw.

That brings us back to the present and our current January thaw. Looking back through the record books indicate even the coldest Januarys on record have “thaws.” What’s perhaps more impressive is that the end of this year’s thaw appears to be seen really before it even begins.

There are so many different drivers trying to take the wheel this winter it, admittedly, makes for an incredibly challenging time of things forecasting. That said, should we see the “stars align” (negative AO, negative NAO, positive PNA) in the coming weeks, this is the type scenario that could carry winter deep into spring.

In the shorter term, as of now we see no reason to abandon the idea the cold reloads to close January and open February. It’s possible that some weather outlets lean heavily on particular model runs and base their mid to long range forecast accordingly. While we agree you have to supplement some of that data into your mid and long range forecast, this is the type pattern than can make for risky business putting all the eggs in one basket.  (We also suggest any outlets leaning solely on operational and ensemble output are in need for a serious dose of dramamine). Instead, we prefer a blend of the above with the foundation being a combination of a nearly ideal SST profile for wintry times continuing and big-hitter analogs. It must also be noted that we have to keep the current AO/ PNA state in the back of our mind.

Speaking of those teleconnections… The current AO and PNA leave a lot to be desired for winter lovers in the longer range:

image image

That said, it should be noted the first two weeks of January cold was in the face of teleconnections that screamed of a warm pattern and a MJO phase that was also mild.

Perhaps the bigger driver here is the surface temperature profile in the PAC and ATL. Also note the modoki El Niño.

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That warmer water sitting across the northeast Pacific Ocean promotes ridging into the PAC NW and AK.  In return the upper level winds tap available arctic air and send it southeast (see the first two weeks of January).

In the mid range, ensemble data is bullish on this aforementioned pattern returning after the very brief January thaw.

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The sensible weather that should result the upcoming 10-12 days?  An active pattern and one that’s very challenging with that northwest flow (we’ll be on clipper watch), biased colder than average.  In fact, the GFS ensembles aren’t too shy about eastern cold week 2.

gefs_t2m_mean_noram_d8_16

Let’s watch things unfold in the coming couple of weeks.  Make it a great day and GO COLTS!

Permanent link to this article: https://indywx.com/2015/01/18/a-word-on-the-longer-range-steady-as-she-goes/

Friday Morning Thoughts…

I’m blessed to have family in town this weekend so posts will be a bit off schedule the next few days, but keep it tuned here as they will come!

What a remarkable January this is as temperatures are averaging more than 9 degrees (fahrenheit) below average AND COLDER than last January.  While I know snow lovers are wanting more snow (yours truly included), one has to sit back and really appreciate the pattern for what it is from a cold standpoint.  I would go as far as to argue this pattern is actually more impressive than last January as the cold has come in the face of what’s been a much less impressive snow pack (for the most part).

ncep_cfsr_noram_t2m_anom

Despite a brief “relaxation” now, models suggest the cold comes on like gangbusters yet again to wrap up the month.  Given where we’ve been and what appears to lie ahead, it would seem as if this January will be even colder than last January- not only through the first half, but at month’s end.  It’ll be fascinating to watch unfold.

Speaking of snow, I still believe this is the type pattern that can “flip on a dime” in the snow department.  The sea surface temperature profile and analogs at least suggest we’re on the playing field for a stormy ride through the month of February and even into March this year.  Does it mean it has to be a snowy pattern?  No, but at this distance it’s at least nice knowing we’re on the field with a chance to win the game.

In the shorter term, a windy “mild up” will occur Saturday as highs reach the middle to upper 40s with a gusty southwest wind in play.  Winds will top 30-40 MPH so you’ll definitely want to “batten down the hatches” Saturday.

gfs_ptype_slp_conus2_7

Permanent link to this article: https://indywx.com/2015/01/16/friday-morning-thoughts/

Relatively Quiet Now, But It Won’t Last Long…

Enjoy our relatively quiet and briefly milder weather pattern as mid and long range guidance suggests we reload the cold with authority and associated wintry precipitation threats…

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Permanent link to this article: https://indywx.com/2015/01/14/relatively-quiet-now-but-it-wont-last-long/

Looking Ahead…

January is off to a colder than average start across a large portion of the country, including the Hoosier state:

ncep_cfsr_noram_t2m_anomThe snow and ice pack has expanded over the past couple of weeks in rather significant fashion:

nsm_depth_2015011205_National

Two storm systems have offered up busy times over the Ohio Valley the past week. Note liquid equivalent numbers the past (7) days- most significant over central Indiana.  Most of this has been in the form of wintry precipitation (snow and ice).

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A weak weather system may offer up light snow chances mid week.  The high resolution NAM and European print off light snow while other models “see” us mainly dry mid week.

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The other big story in the short term will be more bitterly cold arctic air (single digits tonight and close to zero Wednesday morning).

While we’ll certainly “warm” compared to the freezer we’ve been in the first two weeks of January, sneaky arctic highs remain on the field and will put a dent in the air masses from reaching unseasonably mild levels for any length of time this weekend and Week 2.  See Friday’s GFS output and the sneaky arctic high north:

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The next significant storm system brews around the 20th (give or take a day, or two) and could offer up rain or a more wintry option.  Keep a close eye on the period 01.20 – 01.23.

Thereafter, the arctic hounds likely come calling again as the period quickly returns to “lock and load” cold late January into February.  The European and GFS ensembles both show a rebuilding blocking AK ridge and suggest arctic air floods the country yet again as cross-polar flow gets involved:

GFSensembleslateJan

It’s all part of a package that should be the beginning of a colder than average and stormy mid and late winter stretch.  Sea surface temperature anomalies are a textbook setup for a very wintry time of things for our neck of the woods.  Note the Modoki El Nino and warm waters sitting off the PAC NW- both cold/ stormy indicators here:

SSTLateWinterSetUp

Permanent link to this article: https://indywx.com/2015/01/12/looking-ahead/

Ice Storm For Some Sunday Evening; Late Night Thoughts…

Just a quick update to give you some fresh thoughts on the next winter storm that will impact central Indiana.

We bracket the hours of 1p-3p for the onset of sleet and freezing rain across central Indiana.

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Coverage and intensity of freezing rain will increase as we progress through the evening hours.  We suggest hunkering down at home (or at a loved ones home) for the Colts game, as roadways will likely become hazardous during the game.

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Early data hot off the press this evening is suggesting Ice Storm Warning criteria (freezing rain amounts of 0.25″, or greater) is met through the heart of central Indiana.

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A fresh push of cold, arctic, air will ooze back into central Indiana during the day Monday. We think overnight lows head back into the single digits Tuesday morning and below zero Wednesday morning.  Needless to say, should power outages take place, a nasty situation will develop with the new push of cold air.

Please stay tuned to your favorite media or means of obtaining weather information, as this will be an impactful event for central Indiana tomorrow afternoon into Monday.

Permanent link to this article: https://indywx.com/2015/01/10/ice-storm-for-some-sunday-evening-late-night-thoughts/

Dangerous Cold; More Snow Ahead Thursday And Eyeing Sunday-Monday…

Tonight’s video update focuses on the dangerous cold, more accumulating snow Thursday afternoon, and looks ahead to another winter event looming Sunday night and Monday.

Your latest snowfall forecast brought to you by the fine folks at indysportsreport.com:

1815Snow

Permanent link to this article: https://indywx.com/2015/01/07/dangerous-cold-more-snow-ahead-thursday-and-eyeing-sunday-monday/

Dangerous Cold Coming Along With Significant Blowing And Drifting…

The snow storm that moved through northern and central Indiana deposited half a foot, or more, of “champaign powder” for the northern Indianapolis suburbs overnight into this morning with amounts tapering dramatically further south.

Left behind will be a day that will provide “decent” conditions for digging out.  We’ll introduce sunshine and temperatures will be downright “balmy” when compared to what blows into town tonight.  Though well below average, today’s high in the lower 20s will feel like a heat wave when we look ahead to the upcoming couple days.

Things begin to change in a big way tonight as arctic air invades.  Additionally, winds will increase and lead to all sorts of blowing and drifting concerns.  This dry/ powdery snow will be blown about quite easily and lead to reduced visibilities tonight and Wednesday along with significant drifting.  Some additional light snow will accompany the initial arctic push tonight.

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Note the temperature crash that’s coming:

Temperatures fall into the single digits by 10pm.

Temperatures fall into the single digits by 10pm.

Wednesday morning lows.

Wednesday morning lows.

Modeled forecast lows Thursday morning.

Modeled forecast lows Thursday morning.

Officially we forecast the following:

  • Wednesday morning low: -2
  • Wednesday high: 2
  • Thursday morning low: -13

* Wind chill values will fall to 25 to 30 degrees below zero Wednesday into Thursday morning.

Permanent link to this article: https://indywx.com/2015/01/06/dangerous-cold-coming-along-with-significant-blowing-and-drifting/

Monday Evening Snowstorm Video Update:

Our going snowfall forecast stands, brought to you by the fine folks at the Indiana Sports Report (indysportsreport.com):

15141614SnowfallForecast2

IndyWx.com was featured on WIBC today with Ray Steele.  You can listen here:

http://www.wibc.com/news/local-news/here-comes-snow-followed-bitter-cold

Permanent link to this article: https://indywx.com/2015/01/05/monday-evening-snowstorm-video-update/

Brrrrr…. Cold Pattern Continues

Many across the Lower 48 are running MUCH colder than average this morning. Take a look a temperature departures from normal this morning: Mind you this is in the face…

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Permanent link to this article: https://indywx.com/2014/12/31/brrrrr-cold-pattern-continues/

Tuesday Evening: Cold Pattern…

Quick couple updates this evening:

Virtually all of today’s model data has jumped on a stronger storm system for the weekend as opposed to a flatter wave.  This leads to a more northwest track and would imply more “wet than white” for local precipitation types for the weekend.  One important difference between this upcoming event and those of recent past is that arctic air is now on the playing field and this can create all sorts of “havoc” in mid range modeling.  We’ll keep a close eye on things.

The other HUGE item of business we want to get across is the prolonged and rather impressive cold pattern.  A series of arctic highs will come down the Plains and spread southeast the upcoming 7-10 days.  Despite a potential brief spike in temperatures Saturday, it’s a MUCH colder than normal pattern.  Eventually, we’ll have to closely monitor the potential of a couple of snow-producing clipper systems.  Sometimes these can be overachievers, depending on track and intensity and one of two clippers next week may be just that…

More later!  Have a great evening!

Jet Stream Forecast: New Year's Day 2015

Jet Stream Forecast: New Year’s Day 2015

 

Permanent link to this article: https://indywx.com/2014/12/30/tuesday-evening-cold-pattern/

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