Written by Sig Silber
La Nina is coming. There is disagreement on the strength and duration of the La Nina or even if it will be strong enough to qualify as a La Nina rather than ENSO Neutral for this coming winter. What is clear to me is that McCabe Condition A appears to be in place for the next couple of decades so one can take a look at the graphic further down in this article to see what that means for CONUS winters. The paper I discussed last week provides somewhat similar information for the rest of the World.
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.
Updated Seasonal Outlook
NOAA issued their updated Seasonal Outlook on the third Thursday of the month i.e. April 21, 2016 as is their normal schedule. Let’s take a look.
Prior Temperature Outlook for MJJ 2016
New Temperature Outlook for MJJ 2016
Prior Precipitation Outlook for MJJ 2016
New Precipitation Outlook for MJJ 2016
Now let us focus on the long-term situation.
Prior 14 Month Temperature Outlook: May 2016 – Jun 2017
New 14 Month Temperature Outlook: Jun 2016 – Jul 2017
To compare maps from one release to another one needs to remember that the new release drops one three-month period and adds a later one. So to make the comparisons one has to shift the new maps to the right one position and that makes the map on the right drop down to become the left-most map in the next level. I do not have a computer software tool for doing that for you so you have to do it mentally. When I do the comparison I print them out and put them side by side and number the same three-month maps 1, 2, 3,…..,11 in both sets of maps to make it easier for me to easily compare the same three-month period in the new with the previous forecast. One uses the same procedure to compare the precipitation maps. Based on this procedure, I conclude that:
Prior 14 Month Precipitation Outlook: May 2016 – Jun 2017
New 14 Month Precipitation Outlook: May 2016 – Jun 2017
If you want larger versions of each map (temperature and precipitation) you can find them here. And each of those maps can be clicked on to further enlarge them.
Excerpts (somewhat reorganized) from the Discussion Released by NOAA on April 21, 2016
CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS
EQUATORIAL PACIFIC SSTS REMAIN ABOVE CLIMATOLOGICAL MEANS WITH THE LAST FOUR WEEK AVERAGE DEPICTING DEPARTURES FROM NORMAL OF +1.0C OVER THE ENTIRE EQUATORIAL PACIFIC BASIN WITH A FEW AREAS NEAR +1.5C. THE NINO3.4 REGION THREE-MONTH MEAN SST ANOMALY PEAKED AT +2.3C DURING NDJ 2015-2016, BUT HAS DECREASED TO +2.0C FOR THE MOST RECENT THREE MONTH SEASON OF JFM 2016. THE LATEST WEEKLY NINO3.4 REGION ANOMALY IS NOW +1.3C. [Editor’s Note: The new weekly estimate by NOAA is 1.1 and my estimate calculated today is 1.2].
IMPORTANT AND RAPID CHANGES CONTINUE TO BE INDICATED IN SUBSURFACE OCEAN TEMPERATURES. ALTHOUGH OCEAN SURFACE TEMPERATURES REMAIN ABOVE AVERAGE ACROSS THE EQUATORIAL PACIFIC AS NOTED ABOVE, THIS LAYER IS SHALLOW AND ONLY EXTENDS DOWNWARD A FEW TENS OF METERS IN DEPTH, ESPECIALLY ACROSS THE EASTERN PORTION OF THE BASIN. BELOW AVERAGE OCEAN TEMPERATURES (MAGNITUDE OF GREATER THAN 2 DEGREES C) ENCOMPASS A LARGE VOLUME OF WATER FROM 130E TO 90W WITH A THICKNESS RANGING FROM 150 METERS IN THE WESTERN PACIFIC TO 50 METERS IN THE EAST-CENTRAL PACIFIC. ANOMALOUS INTEGRATED (0-300 METERS DEPTH) EQUATORIAL PACIFIC OCEAN HEAT CONTENT BECAME NEGATIVE IN MARCH AND CONTINUES TO DECREASE THROUGH APRIL.
THIS EXPANSE OF NEGATIVE HEAT CONTENT ANOMALIES AT DEPTH MAY BE AN INDICATOR OF A POTENTIAL RAPID TRANSITION TO LA NINA CONDITIONS DURING 2016.
WITH RESPECT TO THE TROPICAL PACIFIC ATMOSPHERE, ENHANCED CONVECTION CONTINUED ACROSS THE CENTRAL PACIFIC BUT WEAKENED EAST OF THE DATE LINE, AND LOW-LEVEL WIND ANOMALIES WERE CLOSE TO AVERAGE OVER THE PAST MONTH. ALTHOUGH THE UPPER-LEVEL ANOMALOUS CIRCULATION REMAINS CONSISTENT WITH EL NINO IT ALSO HAS WEAKENED AS COMPARED TO FEBRUARY AND MARCH 2016.
THE EXTRA-TROPICAL PACIFIC OCEAN REMAINS CONSISTENT WITH THE POSITIVE PHASE OF THE PACIFIC DECADAL OSCILLATION WITH ABOVE AVERAGE SSTS SOUTH OF ALASKA AND ALONG THE WEST COAST. POSITIVE SST ANOMALIES IN THE WESTERN ATLANTIC NEAR THE EAST COAST CONTINUE TO PERSIST AS WELL ESPECIALLY OFF THE NEW ENGLAND COAST.
PROGNOSTIC DISCUSSION OF SST FORECASTS
AS THE CURRENT EL NINO EVENT WEAKENS, SOME CHALLENGES MOVING FORWARD INCLUDE HOW QUICKLY ANY RELATED EL NINO IMPACTS DISSIPATE AS WE MOVE TOWARD ENSO-NEUTRAL CONDITIONS AND WHEN A POTENTIAL TRANSITION TO A LA NINA EVENT MAY OCCUR.
THE CPC SST CONSOLIDATION CONTINUES TO FORECAST A RETURN TO ENSO-NEUTRAL CONDITIONS BY MJJ AND WEAK LA NINA CONDITIONS BY OND, ALTHOUGH THIS IS INFLUENCED STRONGLY BY ONE STATISTICAL FORECAST WHICH MAINTAINS ENSO-NEUTRAL CONDITIONS THROUGHOUT THIS PERIOD INTO THE WINTER MONTHS. IT SHOULD BE NOTED THAT THE CFS AND CA PREDICTIONS INDICATE A TRANSITION TO LA NINA BY ASO 2016. PREDICTIONS FROM THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) MEMBERS ARE IN BETTER AGREEMENT THIS MONTH AS COMPARED TO LAST MONTH AND EXHIBIT GENERALLY TIGHT CLUSTERING WITH THE ENSEMBLE MEAN ENTERING LA NINA TERRITORY (NINO3.4 ANOMALY AT OR LESS THAN -0.5) BY JULY 2016 AND ALL INDIVIDUAL MODELS BY AUGUST.
THE CPC/IRI CONSENSUS FORECAST INDICATES THAT THE TRANSITION TO ENSO-NEUTRAL IS MOST LIKELY BY EARLY SUMMER, AND THE PROBABILITY OF LA NINA DEVELOPING FIRST EXCEEDS 50% IN JAS 2016, TWO OVERLAPPING SEASONS EARLIER THAN FORECAST IN THE OFFICIAL OUTLOOK LAST MONTH.
30-DAY OUTLOOK DISCUSSION FOR MAY 2016
THERE IS LITTLE IN THE WAY OF COHERENT MJO ACTIVITY TO INFLUENCE THE OUTLOOK; THE MJO’S INFLUENCE IS DIMINISHED IN THE WARM SEASON, AND PLAYS NO ROLE HERE IN INFORMING THE MONTHLY FORECAST. SOIL MOISTURE, HOWEVER, IS TAKEN INTO ACCOUNT, AS INCREASING INCIDENT SOLAR RADIATION ALLOWS IT TO EXERT MORE INFLUENCE ON LOCAL TEMPERATURES.
THE CALIBRATED NMME TEMPERATURE PROBABILITIES INDICATE A FAIRLY WEAK TILT TOWARD WARMER-THAN-NORMAL TEMPERATURES ACROSS THE NORTHERN TIER OF THE CONUS, ALASKA, AND PARTS OF THE EASTERN CONUS. A NOTABLE WEAKNESS IS FORECAST OVER THE SOUTH-CENTRAL AND SOUTHWESTERN U.S. THIS IS GENERALLY CONSISTENT WITH LAGGED ENSO REGRESSIONS (USING LATE WINTER NINO 3.4 VALUES), OBJECTIVE COMPOSITE ANALOGS BASED ON THE RECENTLY OBSERVED SSTS IN THE TROPICAL AND NORTHERN PACIFIC AND ATLANTIC BASINS, AS WELL AS STATISTICALLY DERIVED LOCAL SOIL MOISTURE IMPACTS. THE SECULAR TREND EXPLAINS LESS VARIANCE ON MONTHLY TIMESCALES THAN ON SEASONAL TIMESCALES, BUT GENERALLY SUPPORTS THE SPATIAL STRUCTURE OF FORECAST TEMPERATURE PROBABILITIES.
ENHANCED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE INDICATED FOR MUCH OF THE WESTERN, NORTHERN, AND EASTERN CONUS, BASED ON THE ABOVE FACTORS. THE LOWEST PROBABILITIES ARE FORECAST OVER NORTHERN NEW ENGLAND AND THE NORTHERN PLAINS. THE FORMER IS DUE TO HIGHER-FREQUENCY PATTERNS THAT FAVOR ANOMALOUS NORTHERLY FLOW INTO EARLY MAY FOR THAT REGION, WHILE THE LATTER IS DUE TO TRENDS AND SOIL MOISTURE TOOLS. THE LATEST CFS FORECASTS, WEEK 3/4 GUIDANCE FROM BOTH THE CFS AND ECMWF, SOIL MOISTURE CONSIDERATIONS, AND LAGGED ENSO REGRESSIONS FAVOR ENHANCED PROBABILITIES OF BELOW-NORMAL TEMPERATURES ACROSS A PORTION OF THE SOUTHWESTERN AND SOUTH-CENTRAL CONUS.
ALL OF THE AFOREMENTIONED OBJECTIVE GUIDANCE IS IN FAIRLY GOOD AGREEMENT ON THE FORECAST PRECIPITATION OUTLOOK AS WELL. MODEST PROBABILITIES FAVORING ABOVE-MEDIAN PRECIPITATION ARE DEPICTED FOR MUCH OF THE CENTRAL AND SOUTHERN CONUS, EXTENDING WESTWARD TO PARTS OF CALIFORNIA AND THE GREAT BASIN.
MAY – JUNE – JULY
THE MAY-JUNE-JULY (MJJ) 2016 TEMPERATURE OUTLOOK INDICATES INCREASED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ACROSS MUCH OF THE CONTINENTAL U.S. AND ALL OF ALASKA, WITH THE ONLY EXCEPTION BEING AN AREA ACROSS THE CENTRAL AND SOUTHERN PLAINS. THE CHANCES OF ABOVE-NORMAL TEMPERATURES ARE HIGHEST FOR SOUTHERN ALASKA, THE FAR WEST AND THE NORTHEAST WHERE ODDS EXCEED 50 PERCENT.
THE MJJ 2016 PRECIPITATION OUTLOOK FAVORS ABOVE-MEDIAN PRECIPITATION FOR PARTS OF WESTERN AND NORTHERN ALASKA AND A REGION IN THE CONTIGUOUS U.S. THAT STRETCHES FROM NORTHERN CALIFORNIA ACROSS THE INTERIOR WEST SOUTHWARD AND THEN EASTWARD TO INCLUDE THE SOUTHERN PLAINS, GULF COAST AND PARTS OF THE SOUTHEAST. THE GREATEST ODDS FOR ABOVE-MEDIAN SEASONAL PRECIPITATION AMOUNTS ARE FOR NORTHERN ALASKA AND PARTS OF THE CENTRAL ROCKIES, ALTHOUGH ELEVATED CHANCES ARE VERY MODEST. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE UPPER GREAT LAKES REGION.
MJJ 2016 TO MJJ 2017
THE SUITE OF TEMPERATURE OUTLOOKS THIS MONTH ARE SIMILAR TO THOSE RELEASED LAST MONTH AS THE GENERAL THINKING OVER THE OUTLOOK PERIOD REMAINS GENERALLY UNCHANGED, ALTHOUGH POTENTIAL LA NINA IMPACTS WERE CONSIDERED EARLIER THAN IN PREVIOUS SETS OF OUTLOOKS.
OVERALL FOR TEMPERATURE, CHANGES WERE PRIMARILY MINOR ADJUSTMENTS FOR THE FIRST SEVERAL LEADS WHERE PROBABILITIES ARE MODIFIED SOMEWHAT IN SOME AREAS BASED ON THE LATEST CALIBRATED DYNAMICAL MODEL GUIDANCE AND CURRENT SOIL MOISTURE CONDITIONS. FOR MJJ 2016, CALIBRATED MODEL GUIDANCE AND IN SOME AREAS POSITIVE DEPARTURES IN SOIL MOISTURE SUPPORT A SLIGHTLY ADJUSTED REGION OF EQUAL CHANCES (EC) AND A SLIGHT DECREASE IN PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR SOME LOCATIONS IN THE NORTHERN PLAINS, UPPER MISSISSIPPI VALLEY AND GREAT LAKES. PROBABILITIES FOR ABOVE NORMAL TEMPERATURES WERE INCREASED FOR PARTS OF THE FAR WEST AND SOUTHWEST CONUS BASED ON DYNAMICAL MODEL GUIDANCE, LONG TERM TRENDS AND BELOW AVERAGE WINTER AND EARLY SPRING PRECIPITATION.
FOR JJA AND JAS 2016, SIMILAR ADJUSTMENTS WERE MADE, AND PROBABILITIES WERE SLIGHTLY INCREASED ACROSS THE INTERIOR OF THE CONUS DURING ASO 2016 DUE TO POTENTIAL LA NINA CONSIDERATIONS. IN ADDITION TO CALIBRATED DYNAMICAL MODEL GUIDANCE, STATISTICAL GUIDANCE FROM THE SST BASED CONSTRUCTED ANALOGUE TOOL FURTHER SUPPORTS FAVORED ABOVE NORMAL TEMPERATURES FOR MOST OF THE FORECAST DOMAIN FROM JJA 2016 THROUGH SON 2016.
INCREASED CHANCES FOR ABOVE-NORMAL TEMPERATURES FORECAST ACROSS PARTS OF THE SOUTHERN CONTIGUOUS U.S. AND A SLIGHT INCREASE IN THE PROBABILITY FOR BELOW-NORMAL TEMPERATURES ACROSS THE NORTHERN U.S. FROM NDJ 2016-17 THROUGH AMJ 2017 ARE BASED LARGELY ON THE IMPACTS FROM POTENTIAL LA NINA CONDITIONS.
AN INCREASED PROBABILITY OF ABOVE-NORMAL TEMPERATURES FOR THE NORTH SLOPE OF ALASKA DURING THE AUTUMN AND AGAIN IN THE SPRING IS DUE TO THE LIKELIHOOD OF ANOMALOUSLY OPEN SEA ICE AND THE FEEDBACK BETWEEN SEA ICE COVERAGE AND CHANGES IN THE CLIMATE STATE.
THE MJJ 2016 PRECIPITATION OUTLOOK FAVORS ABOVE-MEDIAN PRECIPITATION FOR A REGION STRETCHING FROM NORTHERN CALIFORNIA EASTWARD TO INCLUDE MUCH OF THE INTERIOR WEST, PARTS OF THE SOUTHWEST, SOUTHERN PLAINS AND SOUTHEAST. RESIDUAL EL NINO IMPACTS SUPPORT THE HIGHLIGHTED AREA ACROSS MUCH OF THE WEST AND SOUTHERN PLAINS WHILE DYNAMICAL AND STATISTICAL MODEL GUIDANCE FAVOR AREAS IN THE SOUTHEAST. IT IS IMPORTANT TO NOTE THAT THESE PROBABILITIES ARE QUITE MODEST AND REPRESENT ONLY A SLIGHT TILT TO THE ABOVE-MEDIAN CATEGORY, ESPECIALLY ACROSS THE SOUTHEAST CONUS. BELOW-MEDIAN PRECIPITATION IS MOST LIKELY FOR NORTHERN REGIONS OF THE PACIFIC NORTHWEST AND THE WESTERN GREAT LAKES CONSISTENT WITH ANY REMAINING EL NINO INFLUENCE AND DYNAMICAL MODEL GUIDANCE. AN INCREASED CHANCE OF ABOVE-MEDIAN PRECIPITATION IS ALSO FORECAST FOR WESTERN AND NORTHERN ALASKA THROUGH JJA 2016 BY DYNAMICAL MODELS, RESULTING FROM ANOMALOUSLY OPEN SEA ICE AND WARM OPEN OCEAN TEMPERATURES.
POTENTIAL LA NINA INFLUENCE AND STATISTICAL FORECAST GUIDANCE SUPPORT A SLIGHT TILT IN THE ODDS TO ABOVE-MEDIAN SEASONAL TOTAL PRECIPITATION AMOUNTS FOR COASTAL AREAS OF THE SOUTHEAST DURING JAS AND ASO 2016. POTENTIAL LA NINA CONDITIONS ALSO SUPPORT FAVORED BELOW MEDIAN PRECIPITATION ACROSS PORTIONS OF CENTRAL PLAINS WESTWARD TO THE CENTRAL ROCKIES DURING ASO 2016.
DURING AUTUMN OF 2016 AND WINTER OF 2016-17, THE POTENTIAL FOR ONGOING LA NINA CONDITIONS IS THE PRIMARY FACTOR FOR INCREASED PROBABILITIES OF BELOW-MEDIAN PRECIPITATION ACROSS THE SOUTHERN TIER OF THE CONTIGUOUS U.S. AND THE SOUTHERN COAST OF ALASKA, AND INCREASED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION FOR THE PACIFIC NORTHWEST AND OHIO VALLEY AND CENTRAL GREAT LAKES.
Sometimes it is useful to compare the present month outlook to the three-month outlook
One can mentally subtract the May Outlook from the three-month Outlook and create the Outlook for the last two months in the three-month period namely June and July 2016. When I do that, I deduce that:
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 front 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.
The MJO is not likely to have much of an impact for the month of May as a whole as this MJO cycle appears to be weak and the forecasts of phase changes are contradictory. The MJO has had significant impacts this winter but the impact on May is not likely to be very noticeable. However in the past week some of the models are suggesting a greater but still modest impact than was believed to be the case when NOAA prepared their analysis.
Notice the Northern Pacific is like a giant anticyclone with clockwise motion so that which gets sent west due to El Nino is to some extent returned to North America but at higher latitudes. I am trying to see if I can discern a change in pattern towards lower latitudes for storms arriving from the Western Pacific but so far I do not see that in this animation.
As I am looking at the below graphic Monday evening April 25, I still see a northerly displaced pattern. 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 April 19. 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
And here is the forecast out five days.
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 El Nino.
Below I show the changes over the last month in the Sea Surface Temperature (SST) anomalies.
6 – 10 Day Outlook
Now let us focus on the 6 – 14 Day Forecast for which I generally only show the 8 – 14 Day Maps. The 6 – 10 Day maps are always available in Part II of this report but in the Winter and Spring I often show both maps as the forecasted weather patterns change during that nine day period.
To put the forecasts which NOAA tends to call Outlooks into perspective, I am going to show the three-month AMJ Outlook and the recently updated Outlook for the single month of April and then discuss the 8 – 14 day Maps and the 6 – 14 Day NOAA Discussion within that framework.
First – Temperature
Here is the Three-Month MJJ Temperature Outlook issued on April 21, 2016:
Here is the “Early” Outlook for May Temperatures issued on April 21, 2016.
Below are the current 6 – 10 Day and 8 – 14 Day Temperature Outlook Maps which will auto-update daily and thus be current when you view them. It covers the nine days following the tail end of the current week. I have included both today and probably will continue to do that as long as the patterns are moving from west to east fairly rapidly. I have also included the experimental Week 3 and 4 Outlook. The Week 3-4 Experimental Outlook updates weekly on Friday. Notice the Week 3-4 Experimental Outlook has fewer levels of probability starting with 50%.
6 – 10 Day Temperature Outlook
8 – 14 Day Temperature Outlook
Looking further out.
Now – Precipitation
Here is the three-month MJJ Precipitation Outlook issued on April 21, 2016:
“Early” Precipitation Outlook for May Issued on April 21, 2016
Below are the current 6 – 10 Day and 8 – 14 Day Precipitation Outlook Maps which will auto-update and thus be current when you view them. It covers the nine days following the tail end of the current week. I have included both today and probably will continue to do that as long as the patterns are moving from west to east fairly rapidly. I have also included the experimental Week 3 and 4 Outlook. The Week 3-4 Experimental Outlook updates weekly on Fridays. Notice the Week 3-4 Experimental Outlook has fewer levels of probability starting with 50%.
6 – 10 Day Precipitation Outlook
8 – 14 Day Precipitation Outlook
Here are excerpts from the NOAA discussion released today April 25, 2016.
6-10 DAY OUTLOOK FOR MAY 01 – 05 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 ALEUTIANS EXTENDING TO THE NORTH PACIFIC OCEAN WHILE RIDGING IS PREDICTED DOWNSTREAM OVER THE NORTHWEST CONUS EXTENDING TO WESTERN CANADA. ANOTHER TROUGH IS ANTICIPATED DOWNSTREAM OVER THE NORTHEAST CONUS. THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE TO HIGH SPREAD ACROSS THE MAJORITY OF THE FORECAST DOMAIN. TODAY’S 500-HPA BLEND CHART DEPICTS BELOW NORMAL HEIGHTS OVER MOST OF THE SOUTHEAST CONUS, WHILE ABOVE NORMAL HEIGHTS ARE INDICATED OVER MUCH OF THE NORTHWEST CONUS. 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.
ABOVE NORMAL HEIGHTS AND FORECAST RIDGING OVER THE NORTHWEST CONUS ENHANCE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR MUCH OF THE WESTERN CONUS, AND PARTS OF THE NORTHERN PLAINS AND THE UPPER MISSISSIPPI VALLEY. NEAR TO BELOW NORMAL HEIGHTS AND TROUGHING PREDICTED OVER THE NORTHEAST CONUS FAVOR BELOW NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL AND THE NORTHEASTERN CONUS. ABOVE NORMAL TEMPERATURES ARE FAVORED FARTHER TO THE SOUTH FOR MUCH OF THE SOUTHEASTERN CONUS. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FOR ALASKA AHEAD OF A TROUGH PREDICTED NEAR THE ALEUTIANS.
ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE EASTERN CONUS IN ASSOCIATION WITH THE TROUGH PREDICTED OVER THE NORTHEAST CONUS. CONVERSELY, THERE ARE ENHANCED PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR THE WEST COAST EASTWARD ALONG THE NORTHERN TIER TO THE UPPER GREAT LAKES IN ASSOCIATION WITH FORECAST RIDGING. PRECIPITATION ESTIMATES FROM THE GFS FAVOR ABOVE MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHERN PLAINS, THE CENTRAL PLAINS, AND THE CENTRAL ROCKIES. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MOST OF SOUTHEASTERN ALASKA AHEAD OF A TROUGH PREDICTED NEAR THE ALEUTIANS, WHILE NEAR TO BELOW MEDIAN PRECIPITATION IS FORECAST FOR NORTHWESTERN ALASKA.
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO FAIR AGREEMENT AMONG THE MODELS.
8-14 DAY OUTLOOK FOR MAY 03 – 09 2016
TODAY’S ENSEMBLE MEAN DYNAMICAL MODEL FORECASTS ARE IN FAIR AGREEMENT ON THE PREDICTED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA FOR THE WEEK-2 PERIOD. THE 500-HPA PATTERN DURING THE WEEK TWO PERIOD IS FORECAST TO BE SIMILAR TO THAT IN THE 6-10 DAY PERIOD. TROUGHS ARE FORECAST OVER THE ALEUTIANS AND NORTHEASTERN CONUS, WHILE A RIDGE IS INDICATED OVER THE NORTHWEST EXTENDING TO WESTERN AND CENTRAL CANADA. THE 500-HPA BLEND CHART DEPICTS ABOVE NORMAL HEIGHTS OVER THE NORTHWEST, WHILE BELOW NORMAL HEIGHTS ARE ANTICIPATED OVER MOST OF THE SOUTHERN AND EASTERN CONUS. THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE TO HIGH SPREAD ACROSS THE MAJORITY OF THE FORECAST DOMAIN.
THE FORECAST TEMPERATURE PROBABILITIES FOR THE WEEK-2 PERIOD ARE SIMILAR TO THOSE IN THE 6-10 DAY PERIOD. ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ARE ANTICIPATED FOR THE NORTHWESTERN CONUS AS WELL ALASKA, WHILE NEAR- TO BELOW-NORMAL TEMPERATURES ARE PREDICTED FOR MUCH OF THE EASTERN AND SOUTHERN CONUS EXCEPT FOR MAINE AND SOUTHERN FLORIDA WHERE ABOVE-NORMAL TEMPERATURES ARE FAVORED.
ENHANCED PROBABILITIES FOR ABOVE-MEDIAN PRECIPITATION ARE INDICATED FOR THE EAST COAST AND SOUTHEAST IN ASSOCIATION WITH THE TROUGH OVER THE SOUTHEASTERN CONUS. BELOW MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE PACIFIC NORTHWEST, THE NORTHERN PLAINS, THE UPPER AND THE MIDDLE MISSISSIPPI VALLEY, THE GREAT LAKES, AND THE OHIO VALLEY IN ASSOCIATION WITH FORECAST RIDGING.
PRECIPITATION ESTIMATES FROM THE GFS FAVOR ABOVE MEDIAN PRECIPITATION FOR MOST OF THE SOUTHERN AND SOUTHWESTERN CONUS. EXCEPT FOR THE FAR NORTHWEST, ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MOST OF ALASKA AHEAD OF A TROUGH PREDICTED NEAR THE ALEUTIANS.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO FAIR AGREEMENT AMONG THE MODELS.
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON MAY19
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 Current Conditions
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 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.
|Apr 15, 1992||El Nino||+||–||Modoki Type I or II|
|Apr 4, 1994||La Nina||+||–||Between El Nino’s|
|Apr 23, 1994||La Nina||+||–||Between El Nino’s|
|May 8, 1995||Neutral||+||–||Between an El Nino and a La Nina|
|May 9, 1995||Neutral||+||–||Between an El Nino and a La Nina|
|Apr 13, 1996||La Nina||+||N|
|May 8, 2005||El Nino||+||+||Modoki Type II|
|May 9, 2005||El Nino||+||+||Modoki Type II|
|May 1, 2009||Neutral||–||N||Before El Nino Modoki Type II|
One thing that jumped out at me right away was the spread among the analogs from Apr 4 to May 9 which is five weeks. It suggests that the prior week conditions are highly correlated with weather patterns which in the past occurred over a fairly wide range of dates as shown. There are this time three El Nino Analogs, three ENSO Neutral Analogs and three La Nina Analogs suggesting that it is the PDO rather than El Nino which is in control over our weather for the next 6 – 14 Days or perhaps more accurately the forecast best correlates with periods of time when ENSO was Neutral or the El Nino Modoki state.This makes sense because of the pattern of the warm anomaly along the Equator is consistent with a Modoki even if it did not originate as a Modoki but that can be argued if one looks at the past two winters and not just this winter.
The phases of the ocean cycles in the analogs point clearly towards McCabe Condition A which suggests a low probability of drought for most of the southern tier. That is kind of where the 6 – 14 Day Outlook and the 3-4 Week Experimental Outlook is headed. So it all fits together nicely this week. 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.
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||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||–||+|
Progress of the Warm Event
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|
[Waiting for Queensland to update their site. When they do I will complete the below discussion. The Queensland Site was working on Apr 28 and the below discussion was updated at that time.]
The 30-day average, which is the most widely used measure, as of April 25 was reported at -18.04 which is again clearly associated with an El Nino (usually required to be more negative than -8.0 but some consider -6.0 value good enough). It is quite a bit stronger this week due to strong SOI values all week possibly related to a tropical storm in that area. The 90-day average remains in El Nino territory at -13.71 little 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 continues to be indicative of an El Nino Event in progress but it is pretty much passed the time of year where it is very meaningful re El Nino development. I believe we will see a moderating trend in the SOI from here.
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 light Easterly anomalies, the blue area at the bottom of the Hovmoeller graphic. This is part of the process of cleaning up after this El Nino.
And now the Outgoing Longwave Anomalies which tells us where convection has been taking place.
Let us now take a look at the progress of Kelvin Waves which are the key to the situation. From the earliest to the most recent they can be named #1 through #5. Kelvin Wave #1 has now been pushed off the top of this graphic as more recent information is added at the bottom.
One should keep in mind that for a new Kelvin Wave, the period of time from initiation to the termination of impacts is about six months. So when you have four or five this winter six in a row, the pattern of impacts on different indices and geographic areas becomes quite complex. It is further complicated as you can see above because the Kelvin Waves do not necessarily originate at the same location i.e. longitude.
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. This El Nino appears to be fading slowly from west to east. The real decline will be from east to west.
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 a now equally useful in terms of tracking the progress of this Warm Event as it converts to ENSO Neutral and then La Nina.
Here are the above graphics as a time sequence animation. You may have to click on them to get the animation going.
Let us compare the situation as reported on October 4 to the most recent graphic. Remember each graphic has two parts the top part is the average values, the bottom part is those values expressed as an anomaly compared to the expected values for that date. Generally I am mainly discussing the bottom of the pairs of graphics namely the anomalies
First the October 4 version which I am providing for purposes of comparison. I “flash froze” the daily value that day so that it would not auto-update.
And then the December 14 version which I also “flash froze” to stop it from updating.
And then the current version of the TAO/TRITON Graphic.
The overall pattern is quite a bit less intense than on December 14. We now see a cool anomaly jutting out from Ecuador and sub 0.5C anomalies now extend to 130W. The 3.5C anomaly is no longer visible. Neither is the 3.0C anomaly or the 2.5C anomaly. The 2C anomaly no longer exists in the Nino 3.4 Measurement Area except in a small area south of the Equator where it has recently appeared. So the maximum anomalies (which do not appear everywhere) have declined by a full two degrees Centigrade almost everywhere. This means that if one is attempting to mentally estimate the daily ONI, an approach would be to make an initial estimate of the midpoint of the 1.5C to 2.0C or 1.75C and subtract the reductions from there where the anomaly is less and add back in the small area south of the Equator. Soon we will be subtracting from 1.25C. What I have just described is not exactly the approach I use in my calculation below but it does provide a quick way to get a feel for the current strength of this El Nino. There is actually shading in the TAO/TRITON Graphic that might allow one to try to refine estimates a bit more than the contour lines but I rely on the contour lines. The 1.5C anomaly is also now shrinking although it expanded some this past week. And the western part of the 1.5C anomaly is almost all south of the Equator which means that it has less than half the impact of an anomaly that extends from 5 degrees north latitude to 5 degrees south latitude. This El Nino is crashing.
And an earlier but recent reference point close to the peak of this El Nino re the bottom half of the TAO/TRITON Graphic. You can certainly see the difference that three months makes.
The below table tracks the changes. It only addresses the situation right on the Equator so visually the TAO/TRITON graphic contains more information. But the below table turns visual information into quantitative information so it may be useful. The degrees of coverage shown in the rightmost two columns shows that the extent of the warm water directly on the Equator has been reduced in recent weeks. The way I constructed the table, the 1.0C anomaly as an example includes all water warmer than 1.0C so the 1.5C anomaly is included within it as well as the 2.0C anomaly which you can tell by the way I recorded the westward and eastward coordinates. I could have constructed this table in a different way. Note the 3C anomaly no longer exists. The 2.5C anomaly also no longer exists. As this El Nino decays I am including the less warm anomalies in the table below.
|Subareas of the Warm Anomaly||Westward Extension||Eastward Extension||Degrees of Coverage|
|Today||January 19, 2016||Today||January 19, 2026||Today||January 19, 2016|
* The 2.0 C anomaly is almost all South of the Equator and the 1.5C anomaly which had been South of the Equator again shows up on the Equator. In the above graphic, only the extent to which anomalies exist on the Equator are shown.
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 April 25, in the afternoon working from the April 24 TAO/TRITON report, this is what I calculated.
|Anomaly Segment||Estimated Anomaly|
|Last Week||This Week|
|A. 170W to 160W||1.1||1.6|
|B. 160W to 150W||1.3||1.7|
|C. 150W to 140W||1.5||1.5|
|D. 140W to 130W||1.4||1.1|
|E. 130W to 120W||1.3||0.3|
|Total divided by five subregions i.e. the ONI||(6.6)/5 = 1.3||(6.2)/5 = 1.2|
ONI Recent History
The official reading for Jan/Feb/Mar is now reported as 2.0. I have discussed before the mystery of how the 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.
Is this El Nino a Modoki?
It did not evolve as a Modoki unless you consider it to be a continuation of the Faux El Nino Modoki of 2014/2015 which is a possible interpretation. But the Walker Circulation appears to be much like that of a Modoki. These graphics help explain this.
Although I discussed the Kelvin Waves earlier, now seems to be the best place to show the evolution of the subsurface temperatures.
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 Impacts of Weather Mostly El Nino but possibly Also PDO and AMO Impacts.
Below are snapshots of 30 Day temperature and precipitation departures over the life of this El Nino. The end date of the 30 day period is shown in the graphic. It is a way of seeing how the impacts of this El Nino have unfolded.
Lets take a look at the combined results for the first three months of 2016: January, February and March.
And here is the April weekly (30 day) graphics.
I realize this is a lot of graphics but one needs to look at the history of an event to assess it. As you can see, so far we are not having the expected El Nino Impacts in CONUS.
El Nino in the News
Nothing to report this week
Global Warming in the News
View from Australia
Below is the discussion just released. Notice the discussion re forecasting a La Nina for next winter.
El Niño enters its final weeks
The 2015–16 El Niño is in its last stages. Recent changes in the tropical Pacific Ocean and atmosphere, combined with current climate model outlooks, suggest the likelihood of La Niña forming later in 2016 is around 50%, meaning the Bureau’s ENSO Outlook is at La Niña WATCH.
Eastern tropical Pacific sea surface temperatures have cooled significantly in the past fortnight, and are now approaching neutral levels. As temperatures under the surface are below average, more surface water cooling is expected. However the atmosphere is not responding immediately to these changes, and hence the Southern Oscillation Index (SOI) and cloudiness near the Date Line continue to fluctuate around El Niño thresholds.
Six of eight international climate models suggest the tropical Pacific Ocean will return to neutral levels within the next month. By September, seven of eight models suggest La Niña thresholds are likely. However, individual model outlooks show a large spread between neutral and La Niña scenarios.
La Niña is often, but not always, associated with above-average winter-spring rainfall over northern, central and eastern Australia.
Australia’s climate is also being influenced by record warm temperatures in the Indian Ocean. The warmth in the Indian Ocean may provide extra moisture for rain systems as they cross Australia during the southern autumn.
IOD (Indian Ocean Dipole)
The graphic comes with only a very short discussion and here is that discussion:
Indian Ocean Dipole outlooks
The Indian Ocean Dipole (IOD) is neutral. The weekly Dipole Mode Index value to 24 April was −0.16 °C. The IOD does not typically influence Australian climate during the months December to May, when the monsoon trough is in the southern hemisphere (as positive and negative events are typically unable to form in monsoonal flow).
Currently all international models monitored by the Bureau indicate negative IOD conditions are possible by July. However, model skill is generally lower at this time of year, and outlooks should be used with caution. Negative IOD events are more likely to occur during La Nina.
Sea surface temperatures (SSTs) remain significantly warmer than average across the tropical Indian Ocean.
Information on the impact of a negative IOD on Australia can be found here.
Putting it all Together.
This El Nino has peaked in intensity and is now in rapid decline. We are beginning to speculate on the winter of 2016/2017 which now according to most of the models seems increasingly likely to be a La Nina.
The below is the CPC/IRI forecast issued on April 21, 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 the models 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)
1. Very High Frequency (short-term) Cycles PNA, AO,NAO (but the AO and NAO may also have a low frequency component.)
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