September 2010 Cet

[summer blizzard]

CET dropped to 14.9C yesterday with the CET likely to stay static until mid week when a rise is likely before a drop until the end of the month.

[Stu_London]

14.9C to the 19th after yesterday came in at 13.9C

A mild night last night (13.6c) may push us back up to 15C tomorrow, although we do need to average 16.3 for the 20th for that to happen so it may stay at 14.9C

Certainly a bit of upward pressure for the middle of the week, however, I don't really see us moving up more that 1/10th or so of a degree (at this stage we need days to average 17C for a 0.1C rise). The final third is still a little bit in the air, but looks like being below average to average, so a gentle fall is likely.

If your guess is in the low to mid 14s, you are probably looking good.

[Weather-history]

14.9C to the 19th after yesterday came in at 13.9C

Compare that to Philip Eden's 14.3C

http://www.climate-uk.com/index.html

[BornFromTheVoid]

Going by the GFS the CET will be at 15.0C by the 21st, 15.1C by the 23rd, 14.7C by the 25th, and 14.4C by the 27th.

Low to mid 14s before corrections looks likely and judging by the discrepency Mr Data pointed between the MO and Philip Eden's figures, a big adjustment can't be ruled out.

[Stu_London]

Going by this mornings output, the CET could take a real battering in the last week.

If we are 15C by the 23rd, we need 10.7C for the last week to get down to 14C.

Can it be done?

GFS 0z says yes with potential for a couple of rarish sub 10C September days by the weekend.

Sub 14C after adjustments still possible, although I'd be most happy if I was sat on a punt of 14C exactly.

[BornFromTheVoid]

Agreed. Looking very cool for the time of year next weekend. The 06z would have Saturday averaging around 8C! Could that be close to a record low mean on that day perhaps?

[Thundery wintry showers]

It would be distinctly unusual to get a September day with a CET of just 8C, which would make it the coldest September day in the CET zone since the 30th September 1988. Since 1950, sub 8C days appear to have occurred only in 1952, 1974, 1979, 1986 and 1988.

[Stu_London]

Agreed. Looking very cool for the time of year next weekend. The 06z would have Saturday averaging around 8C! Could that be close to a record low mean on that day perhaps?

I can't see temps being pegged back to 11C widely across the CET zone as GFS is suggesting.

The only scenerio where that might happen is if fog lingers widespread into the afternoon and it might be a bit early in the season for that.

13C or 14C more likely, which would still likely give us a sub 10C day.

[Stu_London]

14.9C to the 19th after yesterday came in at 13.9C

A mild night last night (13.6c) may push us back up to 15C tomorrow, although we do need to average 16.3 for the 20th for that to happen so it may stay at 14.9C

Yesterday came in at 16.4C and the CET stayed at 14.9C (so much for my mathematics!)

last night was 9.6C, so an average of 20.4C will be needed today to make 15C tomorrow.

Wednesday will definately be a rising day, although not by as much as some might think, Thursday looks neutral, with some quite sharp falls looking likely for the weekend

[summer blizzard]

Yesterday came in at 16.4C and the CET stayed at 14.9C (so much for my mathematics!)

last night was 9.6C, so an average of 20.4C will be needed today to make 15C tomorrow.

Wednesday will definately be a rising day, although not by as much as some might think, Thursday looks neutral, with some quite sharp falls looking likely for the weekend

Beggining to think i was a little too high last week in saying 14.3C was likely, i would now say that 14.1C is more likely before ajustments, and given the 0.5C gap between Manley and Hadley, we cannot rule out a large ajustment downward.

[Lettucing Gutted]

Agreed. Looking very cool for the time of year next weekend. The 06z would have Saturday averaging around 8C! Could that be close to a record low mean on that day perhaps?

The coldest mean daily CET ever recorded in September was 28th September 1824 with a CET of only 4.9C! That is colder than the 1971-2000 CET average for December!

http://hadobs.metoffice.com/hadcet/cetdl1772on.dat

[Weather-history]

The coldest mean daily CET ever recorded in September was 28th September 1824 with a CET of only 4.9C! That is colder than the 1971-2000 CET average for December!

http://hadobs.metoffice.com/hadcet/cetdl1772on.dat

Temperatures in the London area that day

Max: 11.1C

Min: -2.8C

The day before it was a maximum of just 8.9C

[Typhoon John]

Temperatures in the London area that day

Max: 11.1C

Min: -2.8C

The day before it was a maximum of just 8.9C

It would be interesting to know with the exact same setup what the temperature difference would be today due to UHI. I suspect it would be significant.

[Stu_London]

still stuck at 14.9C after yesterday came in at 14.8C

should move up to 15.0C today.

[BornFromTheVoid]

Looks like we're still in for at least 1 sub 10C day this weekend.

The GFS 18z would have the CET at 14.7C by the 25th, 14.4C by the 27th and 14.2C by the 30th. Downward adjustments look likely so I guess anyone guessing in the low 14s is in with a shout, outside chance of high 13s as well perhaps?

[Gavin P]

We rise back up to 15.0;

http://hadobs.metoffice.com/hadcet/cet_info_mean.html

[BornFromTheVoid]

Minimum for today is a balmy 13.8C. Maxes look like being just over 18C, most likely to stay at 15C by tomorrows update.

Tonight the min looks like being just over 11C, but the max doesn't look a whole lot higher, maybe 13C so a drop back to 14.9C likely then.

After that the CET looks like being around 14.5C by the 26th, 14.3C by the 28th and 14.2C by the 30th. After adjustments, I'd say 13.8-14.2C now looking best.

[Snowstorm1]

Minimum for today is a balmy 13.8C. Maxes look like being just over 18C, most likely to stay at 15C by tomorrows update.

Tonight the min looks like being just over 11C, but the max doesn't look a whole lot higher, maybe 13C so a drop back to 14.9C likely then.

After that the CET looks like being around 14.5C by the 26th, 14.3C by the 28th and 14.2C by the 30th. After adjustments, I'd say 13.8-14.2C now looking best.

Ooo my 13.8C in with a shout then :')

[Gavin P]

Its all going to come down to how big of an adjustment we get at the end of the month. Certainly there will be some sort of a correction, IMO, if for nothing else than the cold minimums in the early hours of September 1st.

Edited September 23, 2010 by Gavin P

[Cymro]

Much cooler today, can see the set really taking a plummeting now to be onest, and it seems a tad to high in my opinion anyway.

[DAVID SNOW]

Today, tomorrow and sunday will see the CET fall,after that it looks like it will become stable for the last few days IMHO.

So an end figure of 14.3 maybe.

[damianslaw]

CET about to take a real tumble over the coming days with maxes of 13-14 degrees in the CET zone and mins in the range of 5-8 degrees. Thereafter a rise in temps so we will see a little rise in the CET. Finishing mark somewhere within the 14-14.5 range, can't see it getting below 14 degrees unless we see another sharp cooldown at the months tail end, but don't see this happening.

[Optimus Prime]

South and East will probably end up with a larger negative anomaly then many other parts of England

[Gavin P]

So despite parts of the Midlands having their coldest September day since 1994 the CET only falls 0.1c to 14.9;

http://hadobs.metoffice....adcet/cet_info_mean.html

Do we believe this?

[Weather-history]

So despite parts of the Midlands having their coldest September day since 1994 the CET only falls 0.1c to 14.9;

http://hadobs.metoffice....adcet/cet_info_mean.html

Do we believe this?

Yesterday morning wasn't that cold, Gavin. Minima were in double figures. For big drops, you need both parts, maxima and minima to play ball.