Jump to content
Snow?
Local
Radar
Cold?
IGNORED

April 2021 C.E.T. and EWP forecast contests


Recommended Posts

Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

I remember falling snow and hard frosts during the first week of April 2013 (I was in Norfolk at the time). I think some forget just how chilly it was because the week that preceded it was firmly in the exceptional category. CET values for the 1st-7th April:

1st: 1.9°C

2nd: 2.7°C

3rd: 2.7°C

4th: 2.8°C

5th: 4.0°C

6th: 3.8°C

7th: 3.4°C

That's a mean of 3.0°C for the opening week. The cold from the previous month really did linger.

Edited by Relativistic
  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

Yes there were back to back cold starts to April in 2012 and 2013. 2013 gets forgotten given the depth of exceptional cold in March 2013. What a spell if cold!

April 2012 similar to what is happening this month, a major turnaround after the warmth of late March. The 4th brought widespread snow central parts with a bit of height. Again forgotten about . The rest of the month was preety miserable wet windy dull little warmth, and marked the start of a generally very wet colder than normal period through until Autumn. 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: chellaston, derby
  • Weather Preferences: The Actual Weather ..... not fantasy.
  • Location: chellaston, derby
11 hours ago, summer blizzard said:

I don't recall the first half of 2013 being that cold, at least compared to 2012.

 

As a gardener, i do.... i lost just over a weeks work in early April 2013, i lost 1 day in 2012.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

7.8c to the 2nd

1.1c above the 61 to 90 average
0.4c below the 81 to 10 average

___________________________

Current high this month 8.8c on the 1st
Current low this month 7.8c on the 2nd

  • Like 1
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary

Latest projections

AprilProj3.thumb.png.b3918f9d07b785cd3380eefd284a216e.png AprilProb3.thumb.png.2e8285793dda0c088de3f1cd9583b72f.png

The chances of finishing:
Close to average (8.5C to 9.5C) is to 19.4% (2 days ago 22.2%)
Above average (>9.5C) is to 1.6% (2 days ago 6.0%)
Below average (<8.5C) is to 79% (2 days ago 71.8%)

The period of the 3rd to the 8th is forecast to average 4.5C, 3.5C below the 91-20 average.

  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
3 minutes ago, BornFromTheVoid said:

Latest projections

AprilProj3.thumb.png.b3918f9d07b785cd3380eefd284a216e.png AprilProb3.thumb.png.2e8285793dda0c088de3f1cd9583b72f.png

The chances of finishing:
Close to average (8.5C to 9.5C) is to 19.4% (2 days ago 22.2%)
Above average (>9.5C) is to 1.6% (2 days ago 6.0%)
Below average (<8.5C) is to 79% (2 days ago 71.8%)

The period of the 3rd to the 8th is forecast to average 4.5C, 3.5C below the 91-20 average.

Again - only a less than 15% chance of finishing 9c or above on that graph but mark my words, that is where we will end up, due to too much emphasis on very low finishes which in reality are not low chances, they are non existent chances.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

The EWP tracker is probably showing zero, but hasn't actually turned off the March page yet. The next sixteen days on the GFS show very little precip for the grid, probably less than 10 mm, but with some heavier rain approaching on the 19th. 

The CET would probably drop to around 5.5 at some point next week and stay there for a while, then recover steadily after about the 12th to reach a value around 7 C by the 19th. That leaves most forecasts in play since the last ten days could go in either direction, the pattern reached by the 19th looks a bit like a cool spell might reload briefly, but if there were to be a week of very warm weather like we've seen in other months, that could average 13-14 C and from 7 that would shift the CET to around 9 rather quickly. So I would say the colder forecasts need more than a brief reload of cool weather after the 20th if the scenario shown on the GFS is roughly accurate.

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

7.5c to the 3rd

1.0c above the 61 to 90 average
0.4c below the 81 to 10 average

___________________________

Current high this month 8.8c on the 1st
Current low this month 7.5c on the 3rd

  • Like 1
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

The 00z GFS run is colder and basically has nothing but cold weather and brief spells a bit closer to normal from today on, if it were right, the CET by about the 20th would be no higher than 6 C. Note the key phrase, "if it were right." Also with the same caveat, EWP would remain rather low with just small amounts in northerly flow and troughs, not likely to exceed 25 mm by then. Cold-dry seems to be a fairly unusual combination for April, I will look into that some time.

  • Like 1
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

Please could someone post date low maxima records for 5th and 6th April. Good chance we might beat it tomorrow in Scotland at least, possibly today..

Link to comment
Share on other sites

Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary

Low maxima records for the 5th to 15th

image.thumb.png.9e743908effed235a8016597c266bbad.png

 

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary

Latest projections

AprilProj5.thumb.png.54ed612bb00c591d83e6c8c91b9b7aeb.png AprilProb5.thumb.png.f98f5a2f4a48f806503472d5bfcdfc4c.png

The chances of finishing:
Close to average (8.5C to 9.5C) is to 11.7% (2 days ago 19.4%)
Above average (>9.5C) is to 0.4% (2 days ago 1.6%)
Below average (<8.5C) is to 87.9% (2 days ago 79%)

The period of the 5th to the 10th is forecast to average 3.2C, which is 5.2C below the 91-20 average.

  • Like 2
  • Thanks 3
Link to comment
Share on other sites

Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary

The single day drop in the CET maxima from yesterday to today could exceed 8C. In the record for April this has only been achieved 15 times.
Just 2 days have dropped by more than 10C, they are the 12th to 13th last year, -10.6C,  and the 4th to the 5th in 1946, -10.7C.
The graph below compares those 2 big drops with the potential drop for today. Highlights how impressive this drop is given we started at such a lower point.

AprMaxCETDrop.thumb.png.9f754f28dee14a8be7f23e38e8c0becb.png

  • Like 4
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

7.3c to the 4th

0.9c above the 61 to 90 average
0.4c below the 81 to 10 average

___________________________

Current high this month 8.8c on the 1st
Current low this month 7.3c on the 4th

  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

Euro this morning maintained the cool outlook to at least the 13th, it will be interesting to monitor this.

Link to comment
Share on other sites

Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl
9 hours ago, BornFromTheVoid said:

Low maxima records for the 5th to 15th

image.thumb.png.9e743908effed235a8016597c266bbad.png

 

Thanks, are these CET values, or individual stations values? If the latter do we know which stations. 

Some major differences, nearly a 2 degree difference between 5th and 6th.. 9th is an oddity, then a very low figure for the 14th..

Would be good to know record low maxima for today.

Link to comment
Share on other sites

Posted
  • Location: Rotherhithe, 5.8M ASL
  • Location: Rotherhithe, 5.8M ASL
3 hours ago, summer blizzard said:

Euro this morning maintained the cool outlook to at least the 13th, it will be interesting to monitor this.

With ensemble support increasing chance of this April being well below average. Coolest since 2012?
 

A41B973F-5849-4F1D-A7A1-5832F59E4B14.thumb.png.a073538b327bdc3edc7df46b091bfbb2.png

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

I am guessing Those maxima are low CET data, as that very low max on 14th (2.3) matches 1966, it has a lower CET daily mean than other days in the period. The low value today is from 1911 as is the 4.1 for the 6th. The daily minima for those two days were -1.4 and -2.4 (hence the daily means of 0.4 and 0.8). The minima for 1966 include -1.3 (14th) and -0.5 (15th). 

A later benchmark would be 23-25 April 1908, showing max, min and daily means:

23 ___ 4.3 ___ 2.6 ___ 0.9

24 ___ 4.0 ___ 0.5 ___ -3.0

25 ___ 5.0 ___ 1.8 ___ -1.3

Two points of interest. The max and min CET only go back to 1878. There would probably have been lower minima around the 10th of 1837 which set the low daily mean. Also, I notice that in all cases they round down rather than up to get mean daily CET. 

26 ___ +0.2

  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

Euro this morning extends the sub-zero uppers to the 15th, thus delaying any marked warm up.

Link to comment
Share on other sites

Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

Sunny Sheffield at 6.5C  -0.4C below normal. Rainfall 0.5mm 0.9% of the monthly average.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

6.8c to the 5th

0.4c above the 61 to 90 average
0.8c below the 81 to 10 average

___________________________

Current high this month 8.8c on the 1st
Current low this month 6.8c on the 5th

  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

Cold reload after reload to the 22nd now with just a slight hint of moderation then. I could imagine the running CET drifting down into the 5-6 range by this coming weekend and then staying there to the 20th maybe back into low 6 territory by 22nd. The EWP tracker is not working properly (nothing loads for April 2021) but I don't think it is much over 1-2 mm yet, the next ten days look relatively dry although frequent light mixed wintry precip likely, let's say 15 mm, and it gets a bit more active days 11 to 16, for a potential 30 mm by 22nd. 

So I got to thinking, since March managed to rival 1777 for a very warm three-day interval near the end, what led up to the similar events at the end of April 1775? Turns out that April 1775 was quite a cool month to almost the onset of that spell (28th to 30th setting daily records of 16.9, 19.7 and 17.4). By the 20th there had been only one day above 10.0 (mean daily CET) and by the 23rd the running CET was only at 8.3, before finishing on 9.8 with the late warmth (which included two earlier days in the 14-15 range). There was nothing exceptionally cold with 4.7 on the first being the only day below 6, but it was quite chilly for several days in the middle third. 

If that were to repeat this year it would not be all that surprising given the way previous months have warmed up near the end. 

At the other end of the scale, those record cold days in late April of 1908 apparently had a snowfall of epic proportions in parts of southern England, reading a blog post by Phil Eden that came up in my internet search, he says 42 cm of snow fell at Oxford and the Newmarket races had to be called off due to 25 cm snowfall there. That cold spell was 23rd to 26th and a week after a late Easter that was also quite chilly. Although we don't have daily maxima for the 1775 warm spell one could guess they would be in the high 20s to near 30 C, readings that I believe were also achieved in mid-April of 1949. 

  • Like 7
Link to comment
Share on other sites

Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

Sunny Sheffield down to 5.9C -1.1C below normal. Rainfall up to 0.9mm 1.6% of the monthly average.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

6.2c to the 6th

0.3c below the 61 to 90 average
1.4c below the 81 to 10 average

___________________________

Current high this month 8.8c on the 1st
Current low this month 6.2c on the 6th

  • Like 4
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-29 07:13:16 Valid: 29/03/2024 0600 - 30/03/2024 0600 THUNDERSTORM WATCH - FRI 29 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather

    Difficult travel conditions as the Easter break begins

    Low Nelson is throwing wind and rain at the UK before it impacts mainland Spain at Easter. Wild condtions in the English Channel, and more rain and lightning here on Thursday. Read the full update here

    Netweather forecasts
    Netweather forecasts
    Latest weather updates from Netweather

    UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-28 09:16:06 Valid: 28/03/2024 0800 - 29/03/2024 0600 SEVERE THUNDERSTORM WATCH - THURS 28 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather
×
×
  • Create New...