Category: CFSv2

Winter Ideas…

We continue to finalize our winter forecast, which will be posted, as always, here later this month.

As little as only a few months ago, data suggested a major La Nina for the upcoming winter season.  That data has since backed off significantly.  In fact, some runs suggest we’re back into a weak-ish El Nino state by spring.  At the very least, we are confident on avoiding a strong La Nina this winter and lean more in the direction of a weak Nina, at best, to neutral signal.  The CFSv2 is interesting, as always, with the spread in region 3.4.

nino34monadj

sstanimIn addition to the central PAC anomalies, we also are keying in on some other items of interest in the overall SST configuration:

I. Warmth in the GOA (Gulf of Alaska)

Argues for central cold this winter, spreading east with time.

II. Warmth off the eastern seaboard

Will likely serve to limit the ability for the cold to spread east early on in the season

92916sstThe SST CA model is quickly becoming one of our more trusted seasonal forecast models.  We note how it becomes increasingly bullish on a central and eastern trough as winter wears on (by the way, this is likely to go deep into spring this year, too).

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screen-shot-2016-10-02-at-10-53-04-amCold overwhelms the pattern and when you combine it with the active storm track (noted by the green hues, suggesting above normal precipitation through our neck of the woods), confidence is continuing to grow for an above normal snow season.

screen-shot-2016-10-02-at-10-58-16-am

screen-shot-2016-10-02-at-10-58-05-amThe SST configuration on the JAMSTEC would suggest a cold, stormy set-up, locally.  That said, while it sees the above average precipitation, it’s awfully warm at the surface.

ssta-glob-djf2017-1sep2016

tprep-glob-djf2017-1sep2016

temp2-glob-djf2017-1sep2016The NMME (to no surprise…) would suggest a very warm, wet winter.

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screen-shot-2016-10-02-at-11-09-00-am

screen-shot-2016-10-02-at-11-08-47-amAs a reminder, our complete and final annual winter outlook will be posted here during the second half of October.  That will include additional model data, along with several other points behind our reasoning for our winter forecast.  As we always do, we’ll put “pen to paper” when it comes to our winter forecast, including our expected temperature and snowfall anomalies.  Given the data above, including the warm JAMSTEC and NMME, it’s going to be very, very hard to see a warm winter here.  In fact, our idea is for the exact opposite, given the SST configuration, and lines up more closely with the SST CA idea at this point.  We’re also in the camp of a very, very active storm track through the Ohio Valley.  “Big-hitter” potential is present from a winter storm perspective, especially given that we are likely to see resistance from the SE ridge.

Much more later this month…

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Indy 500 And Memorial Day Weekend Video Update…

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Looking Ahead To Christmas Week And The Rest Of December…

Finally, it’s a cold start to the day, and feels like a mid December morning should!  Temperatures are running significantly behind where we were across the east this time yesterday.

t0Highs today will only climb to around freezing across central Indiana.  Add in a stiff NW breeze and wind chills will be colder.  Grab the coat before heading out to finalize that Christmas shopping.

SaturdayHighsThis cold is coming in the face of what’s been a very warm month.  Meteorological winter, as expected, has opened warmer than normal.

DecToDateBy the way, we think changes towards colder loom mid and late January on.  That likely carries us into spring this year with winter continuing.

Christmas week is coming into better focus now, and the “blend” of model solutions was, indeed, the best path to take.  The European’s blow torch 70 degree idea was laughable.  Still warmer than normal, Christmas morning should start in the middle 30s with highs in the upper 40s.

The lead up to Christmas will be an unsettled one after a dry weekend.  Moisture returns Monday.

MondayAnother surge of moisture comes in advance of a cold front and associated area of low pressure Christmas Eve before colder air oozes in.

ChristmasEveChristmas morning opens chilly, but dry, as high pressure is overhead.

ChristmasMorningLooking ahead, an active close to 2015 appears to be in the cards.  Model solutions at this distance have ranged from a major winter storm to a flooding rain threat.  We’re not confident on either idea at this point.  Without blocking, it’ll be mighty tough to get anything wintry from this storm, and we also note models have been overdoing rainfall totals in the 5-10 day range as of late.  That said, is this the storm that can begin to set us up for the expected overall pattern change to winter coming in January?

Note the wild differences between the GFS, GEM, and European for the storm leading up to New Years.

29th

cmc_pr6_slp_t850_conus2_36

ecm_mslpa_conus_11When we turn to the ensembles to attempt to gain a clearer picture of what we can expect, we see they are of no help either.

f228Are we confident of a storm coming to wrap up 2015?  Absolutely, but, again, far less confident on the specifics from this distance.  An overall wetter than average pattern is likely, however.

LateDecTo wrap things up this morning we still note a favorable SST profile for wintry conditions mid and late winter.  In other words, hang in there winter fans.  🙂

sst.anomBy the way, a major crash is coming that will send us into a La Nina by the second half of 2016.  The implications this can have are vast, and include an active severe season and big time Atlantic tropical season.

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Sweaters Or Shorts For Christmas?

Before we get into the thinking behind our set-up for Christmas, we want to be very clear in saying the overall warm pattern will continue as we head through the holiday season and into early parts of 2016.  We do see signs of changes brewing that could (and should) lead to a dramatic flip of the coin for the second half of winter.  With a weakening Nino, it’s also likely that the cold and wintry changes last deep into spring this year, but that’s for another discussion down the road.

In the grand scheme of things, mid and long range model data strongly suggests a very warm pattern remains across the eastern half of the nation, while cold dominates the west, through the end of 2015.

CFSv2

NAEFS

GEFSJust to be clear, we’re very confident on the medium range warmth to wrap up the year (and most likely open 2016).  Contrary to how confident we are on the overall warm pattern through the mid range, we’re much less confident with the shorter term pattern that encompasses the all-important Christmas Eve – Christmas Day forecast.  Getting right to the point, the American GFS forecast model suggests we’re dealing with a FROPA (frontal passage) Christmas Eve night that sets up a blustery, colder Christmas with morning snow flurries possible.  The GFS says we make it into the lower to middle 40s for highs Christmas.  On the flip side, the European model (usually, but not always, more accurate than the GFS) says we blow into early summer-like levels with highs around 70 degrees Christmas, including a mostly dry forecast with strong southwest winds.  How does an afternoon BBQ sound Christmas with that sort of idea?!

When we get down to the dirty details, the differences all have to do with the way the models handle the eastern (Bermuda) ridge.  A snap-shot of the 8-10 day ensemble composite (that shows the Euro, GFS, and Canadian) highlights small, but significant, differences with the ridge placement.

Source: Penn State e-wall

Source: Penn State e-wall

The GFS model (and Canadian, as well) suggests we’re dealing with a more progressive pattern Christmas that results in the cold “sloshing” it’s way east much quicker than its’ European counterpart.  Meanwhile, the European model says the eastern ridge flexes it’s muscle going into the Christmas period and results in the warmer, breezy solution as opined above.

When we dig in further, experience tells us we should “raise an eyebrow” to both solutions.  How many times have we seen the biases that both models have impact the mid to long range forecast?  The GFS has an eastern (more progressive) bias while the European has a western (slower)  bias.  Hint: It’ll be important to remember that as we rumble into more active cold and wintry times come mid and late in the season.

To sum things up, while we’re supremely confident in the long term warm pattern to wrap up the year, we remain very cautious with either solution currently being portrayed by either *normally* more-trusted mid range models.  Lets give it a couple more days and see where things go.  I wish we could be more certain with that all-important Christmas forecast, but we simply can’t at this juncture.  Both solutions have been very consistent with their respected idea for the past couple days.  One thing’s for sure and that’s that we’ll be looking at a major model bust sooner rather than later…

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Changes Are Brewing Friends…

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