First off the latest ENSO update indicates that we are looking a warm neutral tow a weak El Nino for the coming fall and winter months. Here is a write up on this subject from Steve Dimatino
“ENSO neutral conditions are in place via the sea surface temperature anomalies with well above normal SSTA in NINO 4 and well below normal SSTA in NINO 1+2. Overall, if we just go by the statistical ENSO analysis, we have a neutral ENSO environment. The warm SSTA in and around the Dateline supports the development of convection around the Dateline and thus suggest the enhancement of the negative EPO weather pattern.
The atmosphere right now, is behaving more like an El Nino state than neutral. The Subtropical jet stream is becoming enhanced again and the 500 MB alignment is atypical for west based El Nino influences. Given the lack of a MJO influence, the warm pool around 160°E to 160°W is the primary influence from the Tropics on the weather pattern
The latest model guidance, which was just issued yesterday, strongly supports ENSO warm neutral conditions to continue in NINO 3.4 and NINO 4 through the winter. Basically, what you are seeing now is likely what we’ll see through the Fall and Winter. There is a concern that a weak El Nino could reemerge. There is only one model at this time that would suggest La Nina conditions developing.”
If one was to base a winter guess only on the state of the ENSO one would think of a winter similar to last winter
So far this hurricane season has been very quiet but there have been major storms that have hit the United States in August in the past here is a list of some of the storms
1. Hurricane Diane 1955 August 7 to the 23 a category 2 storm
2. Hurricane Camille 1969 August 14 to the 22 a category 5 storm
3. Hurricane Andrew 1992 August 16 to the 28 a category 5 storm
4. Hurricane Charley 2004 August 9 to the 15 a category 4 storm
5. Hurricane Katrina 2005 August 23 to the 31 a category 5 storm
6. Hurricane Irena 2011 August 21 to the 28 a category 3 storm.
With the end of meteorological summer just a week away one has to wonder were did this summer go? Some have stated that this summer has been a hot one will while that may be the case it was not much warmer then last winter was colder then average here is a list of the departures for each month of 2019 so far.
January -2.6°
February -1.2°
March -3.4°
April -0.3°
May -1.7°
June -1.6°
July +2.9°
August so far +1.4°
So while this summer has been warmer than average it has not been that much warmer than average then last winter was colder then average.
Heating and Cooling Degree Days
Here is some information from the NWS on Heating and Cooling Degree Days
Degree days are based on the assumption that when the outside temperature is 65°F, we don’t need heating or cooling to be comfortable. Degree days are the difference between the daily temperature mean, (high temperature plus low temperature divided by two) and 65°F. If the temperature mean is above 65°F, we subtract 65 from the mean and the result is Cooling Degree Days. If the temperature mean is below 65°F, we subtract the mean from 65 and the result is Heating Degree Days.
Example 1: The high temperature for a particular day was 90°F and the low temperature was 66°F. The temperature mean for that day was:
( 90°F + 66°F ) / 2 = 78°F
Because the result is above 65°F:
78°F – 65°F = 13 Cooling Degree Days
Example 2: The high temperature for a particular day was 33°F and the low temperature was 25°F. The temperature mean for that day was:
( 33°F + 25°F ) / 2 = 29°F
Because the result is below 65°F:
65°F – 29°F = 36 Heating Degree Days.
The calculations shown in the two examples above are performed for each day of the year and the daily degree days are accumulated so that we can compare months and seasons.
HOW TO USE DEGREE DAYS:The most common use of degree days is for tracking energy use. Without degree days, comparing the energy used over two periods would be analogous to calculating the miles per gallon rating for your car without knowing how far you had driven. If you wanted to know if the attic insulation you added over the summer was saving energy, you would use your energy bills to determine how much “fuel” was used before and after the retrofit. Then, using the degree days, you could determine “how far you went” during those periods. Instead of calculating miles per gallon, you would determine kWh’s per degree day or therms of natural gas per degree day.
OTHER FACTORS : When comparing energy use, you should also consider other energy uses that are not impacted by weather such as lights, appliances, etc. You can estimate the energy used for these purposes by examining the energy used during temperate months such as May and October when little heating or cooling energy is used. The energy used during these periods reflect your base monthly consumption. Subtracting the base use from the total consumption during a winter month will yield an estimate of the energy used just for heating. It is also important to consider the usage period reflected in your energy bill. Your meter is probably not read on the first day of each month and therefore will not be for the same time period as the degree day totals. You can allow for this by comparing over a longer period, such as an entire heating season or several months.
Here in Michigan we have many more heating degree days than cooling degree days. At Grand Rapids the 30 year average of Heating Degree Days i 6356 with the all time average of 6705 the range has been from 7712 in 1912 to 5253 in 2012. Last winter there were 6722 HDD’s on the cooling side the all time average is 693 with a range of 1200 in 1921 to just 316 in 1992 last summer Grand Rapids had 1003 so far this summer GR is at 626 (that means this year should be warmer than average) By comparisons to a warm location Tampa has a average of 560 Heating Degree Days with a range of 1102 in 1969 to just 141 in 1949 and on the cooling degree days side their average in 3448 with a range of 4490 in 2015 to 2850 in 1901.
Slim
I am sure that Barry has been running his ac all weekend! What a joke!
Upstairs in our bedrooms, yes. No air movement up there and no one would be able to sleep in a hot, stuffy bedroom. Get a life.
Absolutely incredible! Low temps in the Lower 50’s and wasting energy! Wow!
Doesn’t matter what the temps are when half of the inhabitants have bad to severe allergies this time of year. You call it wasting energy, I call it making life more tolerable for our handicapped child and the rest of us.
What a gorgeous day. Spent most of the day outside. Warm sun, cool breeze, and no humidity. Oh, and college football season is starting!
Thanks for the explanation on degree days Slim! Easy to understand it the way you put it. I had forgotten about the 65 being used as the starting point. I think in our house a better number to use would be 60 as we keep our house cooler than most others.
The low here at my house was 50° The current temperature here is 52° with clear skies.
Slim
A cool 48 in Otsego this morning – looking forwards to a good day to work on my deck project….
Nice to see all of these below normal temps! Rock n roll will never die!