Written by Sig Silber
As relative humidity increases, the heat content of the lower atmosphere expresses itself as warmer nights and not quite as hot days. So 600dm may not be as big a threat to life but may be more uncomfortable. We most likely will approach and may reach 600dm this week. The dew point and the position of the Monsoonal Ridge has probably not yet reached the level to declare the Monsoon to have begun. But we are within a week or two of that happening and it may well happen this week for Arizona.
I am beginning to think it will be a wet Summer for the Southwest and perhaps dry for the Plains States but it is not yet clear that this is how it will develop because the prior El Nino was not well behaved and the La Nina that is developing also appears to be a bit westerly displaced. I continue to discuss the Southwest Monsoon siince it is very important to Summer Weather and a topic where science has not yet figured it out. It is very important to the future of many states.
This is the Regular Edition of my weekly Weather and Climate Update Report. Additional information can be found here on Page II of the Global Economic Intersection Weather and Climate Report.
Other than Tropical Storms, the major feature impacting CONUS in the Summer is the Southwest Monsoon or North American Monsoon if you prefer.
Here is a very good paper that explain the U.S. Monsoon.
A METHOD FOR DEFINING MONSOON ONSET AND DEMISE IN THE SOUTHWESTERN USA ANDREW W. ELLIS, ERINANNE M. SAFFELL and TIMOTHY W. HAWKINS Office of Climatology, Department of Geography, Arizona State University, Tempe, AZ 85287-0104, USA
The method employed by the Phoenix NWSFO [Editors’ Note. See below i.e. this method is no longer officially used] in determining the onset and demise of the annual monsoon season locally is the only full attempt at such a declaration. The NWSFO in Tucson only declares the onset, using a similar method to that used at Phoenix, whereas other NWSFOs make no such declarations regarding the monsoon season. The beginning of the monsoon season at Phoenix or at Tucson is defined as the first day of the first occurrence of three successive days during the summer months characterized by mean daily dew-point temperatures of 55°F (12.8°C) and 54°F (12.2°C) or greater respectively. Any subsequent day exhibiting a mean dew-point temperature equal to or greater than the threshold is classified as a ‘monsoon day’ up through to the ending date of the monsoon season. The end date at Phoenix is determined in retrospect by a forecaster upon the review of daily moisture conditions and atmospheric circulation patterns nearing the fall season. Using this method, the monsoon season at Phoenix traditionally begins on 7 July (Table I), but it has begun as early as 19 June and as late as 25 July. Similarly, the season typically begins at Tucson on 3 July (Table I), but it has begun as early 17 June and as late as 25 July. The season at Phoenix typically stretches across a 70 day period through to 14 September (earliest end date: 19 August; latest end date: 10 October), but it has been as short as 34 days and has persisted for as long as 104 days (Table I). Between the beginning and end of the monsoon, the mean number of monsoon days is 55, with a minimum of 27 days and a maximum of 99 days.
An oddity about the recording of Monsoons is discussed in part in this paper. The follow are my comment on their analysis.
Here is a good recent paper on the evolution of the NAM. Mechanisms for the Onset and Evolution of North American Monsoon Ehsan Erfani and David L. Mitchell Desert Research Institute, Reno, Nevada University of Nevada, Reno, Nevada
It focuses on Sea Surface Temperatures (SST’s) and is not a surprise. The reason for the study is interesting. NOAA was having difficulties forecasting precipitation during a Monsoon. It does raise questions about the logic of concluding that Global Warming will reduce the strength of Monsoons. The paper concludes that 29C in the Northern Gulf of California is necessary to have this Monsoon. 27.5C is the general estimate of what causes Convection but apparently the Marine Boundary Level requires 29C for what is called CIN (temperature inversion) to be surmounted. But there are other factors. One has to be creative to figure out how more convection leads to a drier Planet.
Current Situation
The Monsoon Moisture Boundary has already been observed in Southern Arizona. But so far it has only penetrate the lower atmosphere and may not be consistent. Given there are not accepted criteria for defining when a Monsoon has arrived, I conclude that Arizona is still in the pre-Monsoon Phase.
Let’s Now Focus on the Current (Right Now to 5 Days Out) Weather Situation.
A more complete version of this report with daily forecasts is available In Part II. This is a summary of that more extensive report. Worldwide Weather: Current and Three-Month Outlooks: 15 Month Outlooks will take you directly to that set of information but it may take a few seconds for your browser to go through the two-step process of getting to Page II and then moving to the Section within Page II that is specified by this link.
Many graphics in this report are auto-updated by the source of the graphic. It is always my choice as the writer to allow these graphics to auto-update or “freeze them” to what they looked like when I write the article. Generally speaking graphics in research themes which appear above this point do not auto-update as they come from published scientific papers. When I make the decision to allow certain graphics to auto-update, it creates two issues: A. As the graphic updates, my commentary becomes out of sync with the new version of the graphic. This can be very extreme if for example you take a look at my report from months ago. B. On rare occasions, source sites for graphics go down and the graphic does not appear in the article and you probably see white space. If you experience such an event and that graphic is important to your understanding of the report, please return later to view my weather and climate column. Sometimes the “outage” is only for several minutes, but often the duration can be a number of hours or even one or more days. We feel that this inconvenience is preferable to looking at “frozen” weather map images that do not update since I write the article on Monday evenings and you probably do not read it until Tuesday and perhaps later in the week. So I want you to have the advantage of seeing the most up-to-date graphics. If the source is down, the white space is the price paid for most of the time being able to see the latest available graphics. |
First, here is a national animation of weather fronts and precipitation forecasts with four 6-hour projections of the conditions that will apply covering the next 24 hours and a second day of two 12-hour projections the second of which is the forecast for 48 hours out and to the extent it applies for 12 hours, this animation is intended to provide coverage out to 60 hours. Beyond 60 hours, additional maps are available at the link provided above.
The explanation for the coding used in these maps, i.e. the full legend, can be found here although it includes some symbols that are no longer shown in the graphic because they are implemented by color coding.
The map below is the mid-atmosphere 7-Day chart rather than the surface highs and lows and weather features. In some cases it provides a clearer less confusing picture as it shows only the major pressure gradients.This graphic auto-updates so when you look at it you will see NOAA’s latest thinking. The speed at which these troughs and ridges travel across the nation will determine the timing of weather impacts. This graphic auto-updates I think every six hours and it changes a lot. Because “Thickness Lines” are shown by those green lines on this graphic, it is a good place to define “Thickness” and its uses. The 540 Level general signifies equal chances for snow at sea level locations. I am leaving this explanation in the report but it may not be very significant until next October or so.
The MJO has had significant impacts this winter but the impact on June and soon July is not likely to be very noticeable
This graphic updates automatically so it most likely will look different by the time you look at it as the weather patterns are moving from west to east.
Below is an analysis of projected tropical hazards and benefits over an approximately two-week period. This graphic is scheduled to update on Tuesday and I am reading the June 21, 2016 Version and looking at Week 2 of that forecast.
Below is a graphic which highlights the forecasted surface Highs and the Lows re air pressure on Day 6 (the Day 3 forecast is available on Page II of this Report). This graphic also auto-updates.
Looking at the current activity of the Jet Stream which continues to be quite far north.
And here is the forecast out five days with a continuation of the overall northern tendency in the pattern.
To see how the pattern is projected to evolve, please click here. In addition to the shaded areas which show an interpretation of the Jet Stream, one can also see the wind vectors (arrows) at the 300 Mb level.
This longer animation shows how the jet stream is crossing the Pacific and when it reaches the U.S. West Coast is going every which way.
Click here to gain access to a very flexible computer graphic. You can adjust what is being displayed by clicking on “earth” adjusting the parameters and then clicking again on “earth” to remove the menu. Right now it is set up to show the 500 hPa wind patterns which is the main way of looking at synoptic weather patterns.
And when we look at Sea Surface anomalies below, we see a lot of them not just along the Equator related to ENSO.
Below I show the changes over the last month in the Sea Surface Temperature (SST) anomalies.
Four- Week Outlook
I am going to show the three-month JAS Outlook, the recently updated Outlook for the single month of July, the 6 – 10 Day and 8 – 14 Day Maps and the Week 3 – 4 Experimental Outlook
First – Temperature
Here is the Three-Month JAS Temperature Outlook issued on June 16, 2016:
Here is the Early July Temperature Outlook Issued on June 16 (I am not showing the earlier Full Month June Temperature Outlook since by the time you read this article, most of June will not even be represented in the 6 – 10 Day Outlook)
6 – 10 Day Temperature Outlook
8 – 14 Day Temperature Outlook
Looking further out.
Now – Precipitation
Here is the three-month JAS Precipitation Outlook issued on June 16, 2016:
And here is the Early Precipitation Outlook for July Issued on June 16, 2016 (Again, I am not showing the full month June Precipitation Outlook for the same reason I did not show the Temperature version of that Graphic – It is available in last week’s Report).
6 – 10 Day Precipitation Outlook
8 – 14 Day Precipitation Outlook
As I view these maps on June 27 (they update each day), it looks like precipitation leading up to July 22 is tending towards a pattern of a dry northwest, a moderate Monsoon in the Southwest providing moisture for states to the East but ultimately narrowing to just Arizona and New Mexico with the the East Coast having a likelihood of less than climatology precipitation. Again, it is not clear that things can work out as drawn up. There is an indication that towards the end of this period the situation impacting the extreme Northwest may start to change.
Here are excerpts from the NOAA discussion released today June 27, 2016.
6-10 DAY OUTLOOK FOR JUL 03 – 07 2016
TODAY’S MODEL SOLUTIONS ARE IN FAIR AGREEMENT ON THE PREDICTED 500-HPA CIRCULATION PATTERN ACROSS MOST OF THE FORECAST DOMAIN. A TROUGH IS FORECAST OVER THE NORTHEAST WHILE RIDGING IS PREDICTED OVER THE SOUTHWEST CONUS. THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE LOW TO MODERATE SPREAD ACROSS THE MAJORITY OF THE FORECAST DOMAIN. TODAY’S 500-HPA BLEND CHART DEPICTS BELOW NORMAL HEIGHTS OVER THE NORTHEASTERN CONUS, WHILE ABOVE NORMAL HEIGHTS ARE INDICATED OVER THE REST OF THE U.S. TODAY’S MANUAL 500-HPA HEIGHT BLEND IS COMPOSED PRIMARILY OF THE ENSEMBLE MEAN SOLUTIONS, BASED LARGELY ON CONSIDERATIONS OF RECENT SKILL AND ON ANALOG CORRELATIONS, WHICH MEASURE HOW CLOSELY THE MODEL SOLUTIONS RESEMBLE CASES THAT HAVE OCCURRED IN THE PAST.
NEAR TO BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE MIDDLE MISSISSIPPI VALLEY, EASTWARD TO THE OHIO VALLEY, MID-ATLANTIC AND NORTHEAST, ASSOCIATED WITH PERSISTENT TROUGHING. ELSEWHERE IN THE U.S., ABOVE NORMAL TEMPERATURES ARE FAVORED WHERE HEIGHTS ARE ABOVE NORMAL. ABOVE NORMAL TEMPERATURES ARE MOST FAVORED FOR THE GULF COAST STATES, WHERE TEMPERATURE TOOLS ARE IN THE BEST AGREEMENT.
ABOVE NORMAL HEIGHTS INCREASE THE LIKELIHOOD OF BELOW MEDIAN PRECIPITATION FOR THE PACIFIC NORTHWEST, SOUTHEAST TEXAS, AND LOUISIANA. NEAR TO ABOVE MEDIAN PRECIPITATION IS FAVORED FOR THE SOUTHEAST, THE TENNESSEE VALLEY, AND PARTS OF THE OHIO VALLEY IN ASSOCIATION WITH THE TROUGH PREDICTED OVER THE EASTERN CONUS. BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE NORTHEAST, WHILE ABOVE MEDIAN PRECIPITATION PROBABILITIES ARE INDICATED FOR ALASKA, PARTS OF THE CENTRAL PLAINS, AND THE MIDDLE MISSISSIPPI VALLEY, CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLE MEMBERS.
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO FAIR AGREEMENT AMONG THE MODELS AND THE TOOLS.
8-14 DAY OUTLOOK FOR JUL 05 – 11 2016
THE 500-HPA PATTERN FORECAST FOR THE WEEK-2 PERIOD IS SIMILAR TO THE 6-10 DAY PERIOD, BUT MOST OF THE CONUS HAS VERY LOW MAGNITUDE HEIGHT ANOMALIES. NEAR NORMAL HEIGHTS ENHANCE PROBABILITIES FOR NEAR TO ABOVE NORMAL TEMPERATURES FOR MUCH OF THE CONUS. ABOVE NORMAL TEMPERATURES ARE MOST FAVORED FOR THE GULF COAST STATES, WHERE TEMPERATURE TOOLS ARE IN THE BEST AGREEMENT. ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE ALSO ANTICIPATED FOR ALASKA DUE TO PREDICTED ABOVE NORMAL HEIGHTS. FORECAST ABOVE NORMAL HEIGHTS INCREASE THE LIKELIHOOD OF BELOW MEDIAN PRECIPITATION FOR THE PACIFIC NORTHWEST, EASTWARD TO THE NORTHERN ROCKIES. BELOW MEDIAN PRECIPITATION IS FAVORED FOR SOUTHEAST TEXAS AND LOUISIANA, WHILE ABOVE MEDIAN PRECIPITATION IS FORECAST FOR EASTERN ALASKA, THE GREAT LAKES, THE OHIO AND TENNESSEE VALLEY, THE UPPER AND MIDDLE MISSISSIPPI VALLEY, AND PARTS OF THE CENTRAL PLAINS AND SOUTHERN ROCKIES, CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS ENSEMBLE MEMBERS.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE TO FAIR AGREEMENT AMONG THE MODELS AND THE TOOLS.
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON JULY 21
Some might find this analysis interesting as the organization which prepares it looks at things from a very detailed perspective and their analysis provides a lot of information on the history and evolution of this El Nino.
Analogs to the Outlook.
Now let us take a detailed look at the “Analogs” which NOAA provides related to the 5 day period centered on 3 days ago and the 7 day period centered on 4 days ago. “Analog” means that the weather pattern then resembles the recent weather pattern and was used in some way to predict the 6 – 14 day Outlook.
Here are today’s analogs in chronological order although this information is also available with the analog dates listed by the level of correlation. I find the chronological order easier for me to work with. There is a second set of analogs associated with the Outlook but I have not been regularly analyzing this second set of information. The first set which is what I am using today applies to the 5 and 7 day observed pattern prior to today. The second set, which I am not using, relates to the correlation of the forecasted outlook 6 – 10 days out with similar patterns that have occurred in the past during the dates covered by the 6 – 10 Day Outlook. The second set of analogs may also be useful information but they put the first set of analogs in the discussion with the second set available by a link so I am assuming that the first set of analogs is the most meaningful and I find it so.
ENSO Phase | PDO | AMO | Other Comments | |
| June 20, 1953 | Neutral | + | + | |
| June 21, 1953 | Neutral | + | + | |
| June 15, 1961 | Neutral | – | + | |
| June 11, 1979 | Neutral | + | – | Followed by a mild El Nino Modoki Type II |
| June 21, 1979 | Neutral | + | – | Followed by a mild El Nino Modoki Type II |
| June 23, 1979 | Neutral | + | – | Followed by a mild El Nino Modoki Type II |
| June 6, 1996 | Neutral | – | – | After a La Nina |
| July 7, 2003 | Neutral | – | + | |
| June 25, 2006 | Neutral | + | + | Followed by an El Nino |
| June 17, 2007 | Neutral | + | + | Followed by a strong La Nina |
One thing that jumped out at me right away was the spread among the analogs from June 6 to July 7 which is four and a half weeks. I have not examined the centroid of this distribution carefully but if you take out the June 6 and July 7 analogs you end up with about June 15 and these analogs are centered on 3 days and 4 days ago (June 22 or 23). I am kind of concluding that current conditions (as represented in the historical analogs) are generally about a week earlier than for this time of the year. For subjective (difficult to make an analytic case) reasons, that gives me less confidence in the 6 – 14 Day Outlook. It also makes me suspicious of the call of an early start for the Southwest Monsoon.
There are this time zero El Nino Analogs, zero La Nina Analogs and ten ENSO Neutral Analogs. This may simply be suggesting that we are now beyond the time of the year where the Phase of ENSO is very important but it is true that we are in ENSO Neutral Conditions.
The phases of the ocean cycles in the analogs point to McCabe Conditions A and C which are opposites to some extent but both favor a wet Southern Tier. In the selection process for the analogs, those associated with a Positive PDO seemed to have a higher correlation with recent patterns of Highs and Lows so that is no big surprise. The seminal work on the impact of the PDO and AMO on U.S. climate can be found here. Water Planners might usefully pay attention to the low-frequency cycles such as the AMO and the PDO as the media tends to focus on the current and short-term forecasts to the exclusion of what we can reasonably anticipate over multi-decadal periods of time. One of the major reasons that I write this weather and climate column is to encourage a more long term and World view of weather.
You may have to squint but the drought probabilities are shown on the map and also indicated by the color coding with shades of red indicating higher than 25% of the years are drought years (25% or less of average precipitation for that area) and shades of blue indicating less than 25% of the years are drought years. Thus drought is defined as the condition that occurs 25% of the time and this ties in nicely with each of the four pairs of two phases of the AMO and PDO.
Historical Anomaly Analysis
When I see the same dates showing up often I find it interesting to consult this list.
With respect to relating analog dates to ENSO Events, the following table might be useful. In most cases this table will allow the reader to draw appropriate conclusions from NOAA supplied analogs. If the analogs are not associated with an El Nino or La Nina they probably are not as easily interpreted. Remember, an analog is indicating a similarity to a weather pattern in the past. So if the analogs are not associated with a prior El Nino or prior La Nina the computer models are not likely to generate a forecast that is consistent with an El Nino or a La Nina.
| El Ninos | La Ninas | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Start | Finish | Max ONI | PDO | AMO | Start | Finish | Max ONI | PDO | AMO | |
| DJF 1950 | J FM 1951 | -1.4 | – | N | ||||||
| T | JJA 1951 | DJF 1952 | 0.9 | – | + | |||||
| DJF 1953 | DJF 1954 | 0.8 | – | + | AMJ 1954 | AMJ 1956 | -1.6 | – | + | |
| M | MAM 1957 | JJA 1958 | 1.7 | + | – | |||||
| M | SON 1958 | JFM 1959 | 0.6 | + | – | |||||
| M | JJA 1963 | JFM 1964 | 1.2 | – | – | AMJ 1964 | DJF 1965 | -0.8 | – | – |
| M | MJJ 1965 | MAM 1966 | 1.8 | – | – | NDJ 1967 | MAM 1968 | -0.8 | – | – |
| M | OND 1968 | MJJ 1969 | 1.0 | – | – | |||||
| T | JAS 1969 | DJF 1970 | 0.8 | N | – | JJA 1970 | DJF 1972 | -1.3 | – | – |
| T | AMJ 1972 | FMA 1973 | 2.0 | – | – | MJJ 1973 | JJA 1974 | -1.9 | – | – |
| SON 1974 | FMA 1976 | -1.6 | – | – | ||||||
| T | ASO 1976 | JFM 1977 | 0.8 | + | – | |||||
| M | ASO 1977 | DJF 1978 | 0.8 | N | – | |||||
| M | SON 1979 | JFM 1980 | 0.6 | + | – | |||||
| T | MAM 1982 | MJJ 1983 | 2.1 | + | – | SON 1984 | MJJ 1985 | -1.1 | + | – |
| M | ASO 1986 | JFM 1988 | 1.6 | + | – | AMJ 1988 | AMJ 1989 | -1.8 | – | – |
| M | MJJ 1991 | JJA 1992 | 1.6 | + | – | |||||
| M | SON 1994 | FMA 1995 | 1.0 | – | – | JAS 1995 | FMA 1996 | -1.0 | + | + |
| T | AMJ 1997 | AMJ 1998 | 2.3 | + | + | JJA 1998 | FMA 2001 | -1.6 | – | + |
| M | MJJ 2002 | JFM 2003 | 1.3 | + | N | |||||
| M | JJA 2004 | MAM 2005 | 0.7 | + | + | |||||
| T | ASO 2006 | DJF 2007 | 1.0 | – | + | JAS 2007 | MJJ 2008 | -1.4 | – | + |
| M | JJA 2009 | MAM 2010 | 1.3 | N | + | JJA 2010 | MAM 2011 | -1.4 | + | + |
| JAS 2011 | FMA 2012 | -0.9 | – | + | ||||||
| T | MAM 2015 | NA | 1.0 | + | N | |||||
Progress of the Warm Event (Perhaps the title should change and it probably will next week)
Let us start with the SOI.
Below is the Southern Oscillation Index (SOI) reported by Queensland, Australia. The first column is the tentative daily reading, the second is the 30 day moving/running average and the third is the 90 day moving/running average.
| Date | Current Reading | 30-Day Average | 90 Day Average |
| June 21 | -0.9 | +2.70 | -6.25 |
| June 22 | -6.6 | +2.19 | -6.12 |
| June 23 | +2.2 | +1.80 | -5.92 |
| June 24 | +13.1 | +2.29 | -5.61 |
| June 25 | +17.1 | +2.77 | -5.18 |
| June 26 | +11.3 | +2.97 | -4.87 |
| June 27 | +8.5. | +3.23 | -4.60 |
Looks like another week where I will have to complete this analysis on Tuesday as Queensland is behind in their website updating. But from the four days they have posted, The 30-day average, which is the most widely used measure, as of June 24 is reported at +2.29 which is now clearly Neutral but unchanged since last week. The 90-day average barely remains in El Nino territory at -5.61 not much changed from last week. Usually but not always the 90 day average changes more slowly than the 30 day average but it depends on what values drop out. The SOI is no longer associated with an El Nino (usually required to be more negative than -8.0 but some consider -6.0 or even -5.0 value good enough). Similarly +5 to +8 would be the values that different meteorological agencies would look for to conclude the 30 Day SOI was signaling La Nina. The 30 Day indicates current conditions which based on the SOI are neutral with a slight cool bias. The 90 day may be useful for assessed the lagged impacts.
The MJO or Madden Julian Oscillation is an important factor in regulating the SOI and Kelvin Waves and other tropical weather characteristics. More information on the MJO can be found here. Here is another good resource.
Low-Level Wind Anomalies
Here are the low-level wind anomalies. We now see westerly anomalies which are retarding the development of the La Nina. This is an El Nino pattern.
And now the Outgoing Longwave Anomalies which tells us where convection has been taking place.
Equatorial Subsurface Analysis
We are now going to change the way we look at a three dimensional view of the Equator and move from the surface view to the view from the surface down.
Current Sub-Surface Conditions. Notice the lag in getting this information posted so the current situation may be a bit different than shown.
And now the pair of graphics that I regularly provide and which as I publish are currently able to be accessed from the NOAA website:
The above pair of graphics showing the current situation has an upper and lower graphic. The bottom graphic shows the absolute values, the upper graphic shows anomalies compared to what one might expect at this time of the year in the various areas both 130E to 90W Longitude and from the surface down to 450 meters.
The bottom half of the graphic (Absolute Values which highlights the Thermocline) perhaps is now more useful as we shift our focus and begin tracking the progress of this new Cool Event.
It shows the thermocline between warm and cool water. The 28C Isotherm is now located at about 170W. This graphic does not show a 27.5C anomaly which might more precisely indicate where convection is likely to occur. The 27C isotherm is now at about 150W. The situation had actually become less La Nina-ish over the past couple of weeks probably due to the MJO. We should see more expansion of the cold water to the west soon and we are beginning to see that.
Here are the above graphics as a time sequence animation. You may have to click on them to get the animation going.
TAO/TRITON GRAPHIC
And here is the current version of the TAO/TRITON Graphic.
| ———————————————— | A | B | C | D | E | —————– |
The below table which only looks at the Equator shows the extent of anomalies along the Equator. I had split the table to show warm, neutral, and cool anomalies. The top rows showed El Nino anomalies. When there were no more El Nino anomalies along the Equator, I eliminated those rows but I may not have mentioned that a couple of weeks ago when I did that. The two rows just below that break point contribute to ENSO Neutral and after another break the rows are associated with La Nina conditions. I have changed the reference date to May 23, 1016 and may not have announced that in the week when I did that. May 23, 2016 is about when I began to focus on the cool phase of ENSO rather than the warm phase.
Subareas of the Anomaly | Westward Extension | Eastward Extension | Degrees of Coverage | ||||
Today | May 23, 2016 | Today | May 2016 | Today | In Nino 3.4 | May 23, 2016 | |
| These Rows Show the Extent of ENSO Neutral Impacts on the Equator | |||||||
| 0.5C or cooler Anomaly | 175W | 155E | Land | 155W | 80 | 50 | 50 |
| 0C or cooler Anomaly | 165W | 155W | Land | Land | 70 | 45 | 60 |
| These Rows Show the Extent of the La Nina Impacts on the Equator | |||||||
| -0.5C or cooler Anomaly | 160W | 145W | 110W | Land | 50 | 40 | 55 |
| -1C or cooler Anomaly | 155W | 140W | 125W | 105W | 30 | 30 | 35 |
| -1.5C or cooler Anomaly | 145W | 135W | 135W | 120W | 10 | 10 | 15 |
I calculate the ONI each week using a method that I have devised. To refine my calculation, I have divided the 170W to 120W ONI measuring area into five subregions (which I have designated from west to east as A through E) with a location bar shown under the TAO/TRITON Graphic). I use a rough estimation approach to integrate what I see below and record that in the table I have constructed. Then I take the average of the anomalies I estimated for each of the five subregions. So as of Monday June 27, in the afternoon working from the June 26 TAO/TRITON report, this is what I calculated.
| Anomaly Segment | Estimated Anomaly | |
| Last Week | This Week | |
| A. 170W to 160W | +0.8 | +0.4 |
| B. 160W to 150W | +0.5 | -0.1 |
| C. 150W to 140W | +0.0 | -0.5 |
| D. 140W to 130W | -0.1 | -0.6 |
| E. 130W to 120W | +0.2 | -0.3 |
| Total | +1.4 | -1.1 |
| Total divided by five subregions i.e. the ONI | (1.4)/5 = +0.3 | (-1.1)/5 = -0.2 |
My estimate of the daily Nino 3.4 ONI has declined dramatically to -0.2 NOAA has reported the weekly ONI to be even lower at -0.4 which is almost in La Nina territory but still ENSO Neutral. Nino 4.0 is being reported slightly cooler 0.5 still raising questions about if and how fast the Warm Pool is migrating to the West as it dissipates. Nino 3.0 is being reported much cooler -0.3. Nino 1 + 2 which extends from the Equator south rather than being centered on the Equator is being reported as being much cooler at -0.1 and may be the most significant of the readings. WE REMAIN IN ENSO NEUTRAL. I am only showing the currently issued version of the NINO SST Index Table as the prior values are shown in the small graphics on the right with this graphic. The same data in graphical form but going back a couple of more years can be found here.
ONI Recent History
The official reading for Mar/Apr/May is now reported as 1.1. I have discussed before the mystery of how the Nino 3.4 (ONI) CFSv2 values above get translated into the ERSST.v4 values shown below and if NOAA feels that working with two sets of books is a good way to operate, who am I argue. Many businesses do the same thing. As you can see this El Nino peaked in NDJ and is now declining and depending on what system you use it is either the 2nd or 3rd strongest El Nino since modern records were kept which is considered to be 1950. You could argue for it being #1 based on a week of readings but few are buying that argument. Still #2 or #3 means it is one of the strongest ever based on the way these events are measured. I will be writing more about that soon in a separate article. I believe the measurement system is inadequate re being useful in forecasting Worldwide weather impacts.
The full history of the ONI readings can be found here. The MEI index readings can be found here.
Although I did not discuss the Kelvin Waves earlier, now seems to be the best place to show the evolution of the subsurface temperatures which remains relevant.
SST Surface Anomaly Hovmoeller
Here is another way of looking at it: Unlike the Upper Ocean Heat Anomaly Hovmoeller (I call it the Kelvin Wave Hovmoeller) which takes an average down to 300 meters, this just measures the surface temperature anomaly. It is the surface that interacts with the atmosphere and causes convection and also the warming and cooling of the atmosphere. A major advantage of the Hovmoeller method of displaying information is that it shows the history so I do not need to show a sequence of snap shots of the conditions at different points in time. Nevertheless this Hovmoeller provides a good way to visually see the evolution of this El Nino and later track its demise.
Recent CONUS Weather
Here is what May looked like:
But looking at a longer time period in this 90 days or approximately three months.
And now we start to track June.
Here is the most recent 30 day period which covers through June 25.
Weather in the News
Global Warming in the News
Putting it all Together.
This El Nino has ended in terms of current satisfying the criteria. It is possible that officially it may not be declared dead until the end of June because the Mar – Apr – May value of the ONI at 1.1 satisfies the 0.5 cutoff and it is possible that the Apr – May – Jun average ONI may still meet the criteria even though the daily and weekly values no longer meet the criteria.
We are now speculating on the winter of 2016/2017 which now according to most of the models seems likely to be a La Nina or Neutral with a La Nina bias.
The below is the CPC/IRI forecast issued on June 16, 2016. It is important to remember that the first report in each month is based on a survey of meteorologists and the second report later in the month is based on the analysis of the forecast models. It is a minor difference but a difference.
We have suggested that it is possible that some of the models and in particular NOAA’s model will be wrong about how fast the Eastern Pacific Warm Pool moves back towards its La Nina location and it may well be that next winter will be more of a Neutral year or even have some characteristics of an El Nino Modoki and thus be wetter than a typical year as the Warm Pool may still be more in the Central Pacific than shifted all the way west to its La Nina position.
Forecasting Beyond Five Years.
So in terms of long-term forecasting, none of this is very difficult to figure out actually if you are looking at say a five-year or longer forecast. The research on Ocean Cycles is fairly conclusive and widely available to those who seek it out. I have provided a lot of information on this in prior weeks and all of that information is preserved in Part II of my report in the Section on Low Frequency Cycles 3. Low Frequency Cycles such as PDO, AMO, IOBD, EATS. It includes decade by decade predictions through 2050. Predicting a particular year is far harder.
TABLE OF CONTENTS FOR PART II OF THIS REPORT The links below may take you directly to the set of information that you have selected but in some Internet Browsers it may first take you to the top of Page II where there is a TABLE OF CONTENTS and take a few extra seconds to get you to the specific section selected. If you do not feel like waiting, you can click a second time within the TABLE OF CONTENTS to get to the specific part of the webpage that interests you.
A. Worldwide Weather: Current and Three-Month Outlooks: 15 Month Outlooks (Usefully bookmarked as it provides automatically updated current weather conditions and forecasts at all times. It does not replace local forecasts but does provide U.S. national and regional forecasts and, with less detail, international forecasts)
B. Factors Impacting the Outlook
1. Very High Frequency (short-term) Cycles PNA, AO,NAO (but the AO and NAO may also have a low frequency component.)
2. Medium Frequency Cycles such as ENSO and IOD
3. Low Frequency Cycles such as PDO, AMO, IOBD, EATS.
C. Computer Models and Methodologies
D. Reserved for a Future Topic (Possibly Predictable Economic Impacts)
TABLE OF CONTENTS FOR PART III OF THIS REPORT – GLOBAL WARMING WHICH SOME CALL CLIMATE CHANGE. The links below may take you directly to the set of information that you have selected but in some Internet Browsers it may first take you to the top of Page III where there is a TABLE OF CONTENTS and take a few extra seconds to get you to the specific section selected. If you do not feel like waiting, you can click a second time within the TABLE OF CONTENTS to get to the specific part of the webpage that interests you.
D2. Climate Impacts of Global Warming
D3. Economic Impacts of Global Warming
D4. Reports from Around the World on Impacts of Global Warming
