March 2019 C.E.T. and E.W.P. forecast contests

[snowray]

Looks like a finish above 8c is very likely now, although some frosty nights next week could peg things back for a while.

[The PIT]

Sunny Sheffield up to 7.1C, +1.4C above normal. Rainfall 109.8mm 172.4% of the monthly average.

[Roger J Smith]

That running CET of 7.9 ranks 11th highest of the series for 1st to 22nd. Earlier in the thread I posted a list of the top sixteen (six were tied for 11th place) and showed how this year compared to them. We are in roughly the same place now. One year that is ahead of 2019 at 22nd then finished outside the top sixteen (1992). Most of the years that were tied at 7.9 end of month for 11th place (1779, 1780, 1945, 1981, 1991, 1998) were slightly lower than 2019 at this stage (1991 was ahead). All of the others that finished in the top ten (eight with running daily CET) were ahead at this point. We have to keep in mind that this provisional value could be adjusted down later, so we may not be quite as high in the rankings as it appears, since the other years are already adjusted. 

[summer blizzard]

Much like March 2017 we are seeing a high CET anomoly in a month which has felt largely unspectacular.

[BornFromTheVoid]

Below is the estimate of the CET over the next 10 days based on the 12z GFS

The first graph is the forecast with daily max, min, mean and the rolling CET, as well as the 81-10 rolling mean. The second graph is the daily mean in relation the the daily high and low record values.

  

A couple of average days before a mild finish. Minima keeping things respectable, despite some very mild maxima. Anyone guessing in the high 7s or 8.0 looking best after corrections.

[Roger J Smith]

For the 31-day "month" of 20 Feb to 22 Mar (taking 21 Feb to 22 Mar in leap years) this would be tied second warmest with 1997 (8.3) after 1990 (8.7).

 

[The PIT]

No change in sunny Sheffield up to 7.1C, +1.4C above normal. Rainfall 109.8mm 172.4% of the monthly average.

[Summer Sun]

7.9 to the 23rd

2.5c above the 61 to 90 average
1.6c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[damianslaw]

Another appreciably above average month on the cards, but not most likely on the same league as February. Not sure what the mins have been, but I suspect it is these which has held the CET up, maxima haven't been especially high. A marked north-south divide as well this month, the CET zone just outside any colder conditions, so not very representative of how things have been further north.

The next few days could see some lower min values though, cancelled out by mild maxima.

 

[summer blizzard]

30 minutes ago, damianslaw said:

Another appreciably above average month on the cards, but not most likely on the same league as February. Not sure what the mins have been, but I suspect it is these which has held the CET up, maxima haven't been especially high. A marked north-south divide as well this month, the CET zone just outside any colder conditions, so not very representative of how things have been further north.

The next few days could see some lower min values though, cancelled out by mild maxima.

 

February was like 2C above average, this will only come out 1C above average.

[Earthshine]

1 hour ago, summer blizzard said:

February was like 2C above average, this will only come out 1C above average.

February was 3.0°C above average and March is currently running at 2.5°C above average.

https://www.metoffice.gov.uk/hadobs/hadcet/cet_info_mean.html

[summer blizzard]

6 hours ago, Evening Star said:

February was 3.0°C above average and March is currently running at 2.5°C above average.

https://www.metoffice.gov.uk/hadobs/hadcet/cet_info_mean.html

That's using the outdated mean that they only use for consistency (if we are going to do that, let's use the 1700-2018 mean). 

Against the 1981-2010 mean we are looking at +2.3C and 1.xC.

[Earthshine]

12 hours ago, summer blizzard said:

That's using the outdated mean that they only use for consistency (if we are going to do that, let's use the 1700-2018 mean). 

Against the 1981-2010 mean we are looking at +2.3C and 1.xC.

It's not outdated.  It's the standard period of reference recommended by the WMO.  The more recent climate period has been substantially raised as a consequence of AGW (probably the reason it isn't currently being used as the standard as of now).

[Summer Sun]

7.9 to the 24th

2.4c above the 61 to 90 average
1.5c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[The PIT]

Sunny Sheffield at 7.1C still +1.3C above normal. Rainfall 109.9mm 172.5% of the monthly average.

[Summer Sun]

7.9 to the 25th

2.4c above the 61 to 90 average
1.5c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[The PIT]

Sunny Sheffield at 7.2C +1.4C above normal. Rainfall unchanged.

[Roger J Smith]

Guidance is looking quite cold for April, so here are some stats about Aprils that were colder than March and February (or equal in CET).

I have listed all the cases in the 360 year CET record in clumps of 30 years to arrive at the 1991-2018 period.

As 1659 and 1660 had Aprils warmer than Feb or Mar, we can start at 1661 to 1690. 

This is colour coded to show the rare April colder than February cases. When it was April colder than both Feb and Mar, the type changes to blue. This includes one case (1702) where March was colder than February and equal to March in CET. 

When it was April colder than February but not March, the type is green. That includes three cases where April was equal to February (1713, 1743,  and 1837 where tied coldest April on record followed an even colder March but was equal to a somewhat mild February).

Just April colder than March are in regular black type.There was one case (1991) where April was equal to March (and not colder than February as in 1702).

After the year, the monthly CET values are shown, Feb is included only when it's colder than or equal to April. 

1661-1690 _ no cases

1691-1720 _ 1702 (6.7, 5.8, 5.8) ... 1713 (5.5, 4.5, 5.5) ... 

1721-1750 _ 1739 (6.8, 5.8, 6.7) ... 1743 (5.4, 5.3, 5.4) ... 1750 (8.2, 7.7)

1751-1780 _ 1780 (7.9, 6.3)

1781-1810 _ 1790 (6.6, 6.4, 6.1) ... 1809 (5.7, 6.0, 5.2)

1811-1840 _ 1837 (4.7, 2.9, 4.7)

1841-1870 _

1871-1900 _

1901-1930 _ 1903 (7.1, 7.1, 6.4)

1931-1960 _ 1936 (7.1, 6.3) ... 1938 (9.1, 7.6) ... 1957 (9.2, 8.9)

1961-1990 _ 1978 (6.7, 6.5) ... 1981 (7.9, 7.8) ... 1989 (7.5, 6.6) ... 1990 (8.3, 8.0)

1991-2018 _ 1991 (7.9, 7.9) ... 1998 (7.9, 7.7) ... 2012 (8.3, 7.2) ... 

______________________________________________________________

In summary then, there are 16 cases where April is colder than March, and 8 where it is colder than February (including ties). There were 20 years in total where one or the other (Feb and or Mar) was milder than April (or equal). 

The greatest decrease from any March to any April was 1.6 deg in 1780. The greatest decrease from any February to any April was 0.9 deg in 1702. Only 1790 had two CET drops in a row (other cases had some equal values or went up then down between Feb, Mar and April). 

This is a rather strange phenomenon over time.

The main portion of the Maunder minimum never produced a case. Then, there was a long interval (1702 to 1837) when February was on four occasions milder than April (or equal) even though March was not. There were three other cases in that interval where both Feb and Mar were milder than April, and two where it was just March (so a total of 9 out of 136 where April was colder than one or both). 

Then from 1838 to 1902 (the Victorian era, oddly) there were no cases at all. 

Since 1903, when April was colder than both, there have been ten more cases (a total of 11 out of 116) with just March warmer than April. The 1990 and 1998 sets had mild Februaries but April did not turn that much colder. It does appear that the mild March - colder April phenomenon is increasing in recent decades with seven of the twenty cases listed happening from 1978 to 2012. That frequency is 3.5 times the average. The only other period with a cluster to match it would be 3/12 from 1739 to 1750 (expected at random 0.7). 

It can be seen that most of the more recent warm Marches were followed by colder Aprils. The exceptions include 1945, 1961 and 2017.

If this year does produce an April colder than February, it would be the first time since 1903. 

April has never been colder than January in any calendar year. It was equal in 1696 (5.5) and 1782 (both 5.2) and came within 0.1 in 1983 (Jan 6.7, Apr 6.8). 

April was colder than the previous December eight times and equal once. In 2016 the deficit was 2.2 degrees after the record mild December in 2015. 

April was colder than the following December in the same calendar year also on eight occasions with one tied. 

Edited March 26, 2019 by Roger J Smith

[Summer Sun]

7.8 to the 26th

2.4c above the 61 to 90 average
1.4c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[The PIT]

Sunny Sheffield still at 7.2C, +1.3C above normal. Rainfall Unchanged at 109.9mm 172.5% of the monthly average.

[Summer Sun]

7.9 to the 27th

2.4c above the 61 to 90 average
1.5c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[Derecho]

1 hour ago, Summer Sun said:

7.9 to the 27th

2.4c above the 61 to 90 average
1.5c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

Looks like I have gone too low! Saturday is now looking 7-8 degrees warmer here in the model output compared to just 2 days ago and the cooler air doesn't  even make it to the south now.

I reckon the final CET will finish at 8.0C following the end of month adjustments.

[The PIT]

Sunny Sheffield at 7.3C +1.3C above normal. Rainfall unchanged. Probably end up about 7.6C for us. Unlikely to be much more rain on the forecast so that is likely to end up at 109.9mm and 172.5% of average.

[Summer Sun]

7.9 to the 28th

2.3c above the 61 to 90 average
1.4c above the 81 to 10 average

_________________________________________

Current high this month 8.9 to the 3rd

Current low this month 7.1 to the 13th

[The PIT]

Sunny Sheffield at 7.4C +1.4C above normal. Rainfall unchanged at 109.9mm 172.5% of average.