Category: El Niño

2019 IndyWx.com Summer Outlook

2019 is absolutely flying by! Before you know it, we’ll be releasing our 2019-2020 Winter Outlook. Kidding- sort of. 😉

Is a blazing hot summer in store for central Indiana, or perhaps wet and cool? Let’s dig in to the details…

As we look at current sea surface temperature anomalies, a few items stand out:

I. We expect a weak El Nino to continue through meteorological summer (June through August), and perhaps even into next winter.

II. MDR (Main Development Region for tropical entities) is running cooler than normal and would suggest an overall “less busy” hurricane season from a long-track perspective

III. SSTs are running much warmer than normal in the Gulf of Mexico and off the East Coast. This is important as while the long-track tropical systems may not be as frequent, we’ll have to remain on guard for the potential of active times closer to home this season. Additionally, these warmer anomalies tend to lead us to believe precipitation will run above normal across coastal areas into the Deep South this summer.

Let’s look at some of the climate computer model data for the summer season:

The latest IRI model (International Research Institute) shows relative warmth along the coastal areas and the west with greatest wet anomalies across the Northwest.

The CFSv2 is leaning towards an anomalously wet summer across a widespread portion of the country (exception being New England).

As we review the CanSIPS, it likes the idea of a cool, wet summer across the Heartland with warmth along the coasts.

The European Seasonal Forecast has a seasonal summer for most of the country with warmth along the coasts, and a reflection of wetter anomalies across the northern Plain into the Northwest.

(The JMA Seasonal hadn’t updated as of this post).

After taking into account the various seasonal model data above (which is in remarkable overall agreement for a LR forecast idea), along with the current SST configuration, and analog data, this is how we see the Summer of 2019 playing out.

Specific to central Indiana, we’re forecasting a rather wet and cooler than average summer. Frequent storm systems should keep things active around these parts for the balance of the summer season, with the temperature scale tipping a touch cooler than normal.

While the number of named storms should be down compared to normal (highlighted by the Euro seasonal precipitation idea), we’ll have to keep close tabs on the Gulf of Mexico and off the Southeast coast for the potential of “last minute” development. Those warmer than normal sea surface temperatures lurking off the coast does warrant concern for at least the threat of another active year from a landfall perspective.

Permanent link to this article: https://indywx.com/2019-indywx-com-summer-outlook/

2019 Spring Outlook…

2019 IndyWx.com Spring Outlook

Forecaster: Team; Date Issued: 02.16.19

Last spring was a tale of two seasons in itself. March (featured a foot of snow) and April were significantly colder than normal and then we shifted things to summer in May (the last month of meteorological spring was close to 10 degrees above normal). As a whole, it was a quiet severe weather season.

Despite the wild swings, at the end of the day, things “balanced out” nicely across the central Ohio Valley, including central Indiana.

As we look ahead to what the 2019 version holds, here are a few headlines that have our attention:

I. Weak Nino is behaving more like a Nina (Tropical Northern Hemisphere pattern can be thanked for this).

II. Neutral NAO is expected

III. Neutral PDO (Pacific Decadal Oscillation)

In addition, we’re paying special attention to the SST configuration in the Gulf of Mexico. A warmer than average GOM can most certainly lead to a more “hyper” severe weather season as spring gets going.

The late winter/ early spring drought monitor can give a hint where early warmth may try and get going. However, this year, we can’t rely on this tool as the Plains and East, including the heart of the #AGbelt, have seen copious amounts of moisture over the winter.

Drought Monitor as of 2/14/19
December 2018 Precipitation Anomalies
January 2019 Precipitation Anomalies

Let’s look at what the model guidance is printing out for meteorological spring:

JMA

March
April
May

CFSv2

JAMSTEC

European Seasonal

Summary

We anticipate a slightly warmer than average spring season across not only central Indiana, but the Mid West and Ohio Valley region, as a whole. A weak El Nino is expected to persist into the upcoming summer and the conditions typically associated with such should eventually show themselves (as opposed to more of a Nina-like flavor now) through the spring. We agree with the consensus of model guidance above that March is likely to feature the coldest temperatures, relative to normal, and that’s primarily due to what should be a colder 1st half of the month before more bonafide spring conditions take hold the 2nd half of the month. Precipitation is anticipated to run near average, if not slightly below average, levels through the spring. As for severe weather, we expect a much busier season than last year, especially with the warm SSTs lurking in the Gulf of Mexico.

Permanent link to this article: https://indywx.com/2019-spring-outlook/

Trying to Answer Questions When Winter Will Show Up…

Daily, we’re receiving questions around if and when winter will show up. While admittedly later than originally thought here, we’ve never been in the camp of “throwing the towel” in on winter. Our winter outlook that includes below normal cold and near average snowfall remains unchanged.

Before we get into some of our reasons why we think winter will show up (and likely make up for lost time), the upcoming week will remain much warmer than average.

We’re tracking (3) storm systems that will deal the region rain over the upcoming week:

  1. Southern IN this afternoon and evening
  2. All of the state Monday
  3. All of the state next Friday into Saturday

As a whole, rainfall amounts won’t be particularly impressive for most, with 7-day totals between 0.25″ to 0.75″ for central portions of the state. Heavier amounts can be expected across southern areas.

Now, let’s look ahead to some potentially colder times. Before moving forward, it’s important that we recognize models have attempted once already to drive in a wholesale pattern change to colder (originally thought to be underway now). Perhaps it’s a case of “delayed, but not denied.” There’s a lot going on behind the scenes:

  • Sudden stratospheric warming event and potential polar vortex displacement, etc.
  • SOI flipping from a Niña-like state to one we’d expect to see associated with an El Niño
  • Active MJO remains

There are significant changes brewing in the arctic/ higher latitudes that have to raise an eyebrow at the very least.

Today

Mid-January

Note the higher pressures building over the upcoming 10-14 days in the arctic regions.

Not surprisingly, the models begin to tank the AO.

The PNA rises…

Something that also lends credence to a potential pattern shift is the recent SOI drop.

This would tend to suggest that an active storm track may be in place as the more bonafide cold shift is underway.

The moral of the story? Despite the milder period being extended a couple weeks longer than originally thought, there’s still a lot on the table this winter. It’s far too early to think winter’s over before it’s really even begun for most. We expect to see increasingly wintry conditions show up around the middle of January…

Stay tuned.

Permanent link to this article: https://indywx.com/trying-to-answer-questions-when-winter-will-show-up/

Deeper Look Into The Long Range…

You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access.  Already a member of IndyWx.com All-Access?  Log-in here.

Permanent link to this article: https://indywx.com/deeper-look-into-the-long-range/

A Word (Or Two) On Where We Think This Pattern Is Going…

Before we get into the updated thinking on the pattern, lets review what we have out:

  • Step-down process to cooler/ colder weather begins in mid-November.
  • Thanksgiving-Christmas period, as a whole, turns wintry and is snowier than average.
  • Our complete 2016-2017 Winter Outlook can be found here.

The first week of November has featured an incredibly warm start to the month. (Image courtesy of MRCC).

month-tdevSpeaking of warmth, 2016 has been a very warm year.

ncep_cfsr_t2m_anom_ytd(The cold of 2014 seems so long ago…)

ncep_cfsr_t2m_anom_2014Back 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).

Despite being in a weak La Nina, the pattern is taking a while to respond.  Remember, we’re coming off one of the strongest El Ninos on record.  Until we slow the PAC jet, significant, long-lasting, changes won’t occur.  We can lean on the AAM (Atmospheric Angular Momentum) forecast for clues as to when this may occur.  You can read more about the AAM here.  My fellow local weather compadres, Michael Clark, Ed Valley, and Kirk Hinz have also written/ blogged extensively about the AAM and resulting impacts.

gfsgwo_1

gfs1When 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.

If we can finally get the westerlies to slow, other elements are in play that could (and should) lead to a colder pattern as we move forward.  Our (3) big teleconnections are in a position favorable for cold for mid/ late November, into early Dec.

cw5yrrsxaaefhiy-jpg-largeAdditionally, the EPO is forecast negative off the GEFS and EPS. (Images courtesy of Weatherbell.com).

eps_epo_bias

gefs_epo_12Again, this is a cold signal. (Image courtesy of Madusweather.com).

eponew_neg_11novThe 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).

cw5qrw0wgaaphxr-jpg-largeIn 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…

Permanent link to this article: https://indywx.com/a-word-or-two-on-where-we-think-this-pattern-is-going/