The met Office forecast for the Peak District issued at 0410 this
morning is a bit odd. For 0600 the weather was forecast to be sunny
despite the fact that sunrise wasn't until 0705. The forecast
temperature for 300m a.s.l. was 11°. In Tideswell, at 300m, the actual
temperature at 0600 was -0.4°.

The forecast temperature at 300m for 0900 is also 11°. This also seems
unlikely as the current temp(at 0725) is -0.9°.

Very curious.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr

On Monday, 25 February 2019 07:27:54 UTC, Norman Lynagh wrote:
The met Office forecast for the Peak District issued at 0410 this
morning is a bit odd. For 0600 the weather was forecast to be sunny
despite the fact that sunrise wasn't until 0705. The forecast
temperature for 300m a.s.l. was 11°. In Tideswell, at 300m, the actual
temperature at 0600 was -0.4°.

The forecast temperature at 300m for 0900 is also 11°. This also seems
unlikely as the current temp(at 0725) is -0.9°.

I can't explain the "sunny before sunrise" bit, but the temperature forecast is probably one for the "free air" (or maybe hilltop) temperature taken from the model forecast, as there is a very low inversion this morning. I'm guessing you are in a valley of sorts? At Leek, not so far from you, the temperature was 8.3 at 0700z, with a dew point of -3.

--
Freddie
Ystrad
Rhondda
148m AMSL
http://www.hosiene.co.uk/weather/
https://twitter.com/YstradRhonddaWx for hourly reports (very few tweets getting through currently)
Stats for the month so far: https://www.hosiene.co.uk/weather/st...201902FEB.xlsx

Freddie wrote:

On Monday, 25 February 2019 07:27:54 UTC, Norman Lynagh wrote:
The met Office forecast for the Peak District issued at 0410 this
morning is a bit odd. For 0600 the weather was forecast to be sunny
despite the fact that sunrise wasn't until 0705. The forecast
temperature for 300m a.s.l. was 11°. In Tideswell, at 300m, the
actual temperature at 0600 was -0.4°.

The forecast temperature at 300m for 0900 is also 11°. This also
seems unlikely as the current temp(at 0725) is -0.9°.

I can't explain the "sunny before sunrise" bit, but the temperature
forecast is probably one for the "free air" (or maybe hilltop)
temperature taken from the model forecast, as there is a very low
inversion this morning. I'm guessing you are in a valley of sorts?
At Leek, not so far from you, the temperature was 8.3 at 0700z, with
a dew point of -3.

I think the answer is probably a bit too much model-watching and not
enough keeping a watch on what is actually happening.

Tideswell village sits in Tideswell Dale and is about 50 metres or so
below the surrounding countryside. Our house is above the village just
where the land starts to level out. Tideswell is actually near the
middle of a limestone plateau that has an extent of something over 100
square miles. Much of it is at 300-350m a.s.l., some parts a bit higher
and some, mainly in the valleys, a bit lower. The temperatures that I
record are typically very similar to those at other locations across
the plateau. That was the case this morning so it wasn't the we had an
anomalous low 'blip'. There certainly was a low level inversion. At
Flash (about 490m), for example, which is about 9 miles SW of here, the
temperature 'flat-lined' at about 10°throughout the night. In
Tideswell and Buxton the temperature fell below 3° around midnight and
continued to fall slowly thereafter. At the time the offending forecast
was issued (0410) the temperature in Tideswell was +0.7° and at Buxton
it was +1.0°. These were typical of temperatures across the plateau at
the time. With sunrise not due until 0705 the prediction of 11° for
0600 was fanciful.

As I say, probably a bit too much model-watching and not checking what
was actually happening. Or, as happens all too often, perhaps just
regurgitating the previous afternoon's issue of the forecast with the
only change being the stated time of issue. It shouldn't happen but it
often does. Unfortunately, in this case I don't have yesterday
afternoon's issue to check.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr

Freddie wrote:

On Monday, 25 February 2019 07:27:54 UTC, Norman Lynagh wrote:
The met Office forecast for the Peak District issued at 0410 this
morning is a bit odd. For 0600 the weather was forecast to be sunny
despite the fact that sunrise wasn't until 0705. The forecast
temperature for 300m a.s.l. was 11°. In Tideswell, at 300m, the
actual temperature at 0600 was -0.4°.

The forecast temperature at 300m for 0900 is also 11°. This also
seems unlikely as the current temp(at 0725) is -0.9°.

I can't explain the "sunny before sunrise" bit, but the temperature
forecast is probably one for the "free air" (or maybe hilltop)
temperature taken from the model forecast, as there is a very low
inversion this morning. I'm guessing you are in a valley of sorts?
At Leek, not so far from you, the temperature was 8.3 at 0700z, with
a dew point of -3.

It's happened again this morning. The Peak District forecast issued at
0343 this morning predicted a temperature of 13° at 300m at 0600
today. Actual temperatures at 0600 we

Tideswell (303m): +0.4°
Buxton (335m): +0.6°
Wardlow (299m): +2.8°
Curbar (251m): +2.6°
Burbage (298m): +2.9°

I raised this issue with the Met Office yesterday. They confirmed that
the temperature predictions in these forecasts are straight out of the
model and that the model isn't handling the low-level inversion very
well. Their response included the following

-------------------------------------------------------------
Of course, the problem with automated data is that it does have the
inevitable downside of performing especially badly in some very
specific weather situations, and causing the errors that you have
rightly mentioned.
-------------------------------------------------------------

My view has always been that raw model output is a tool for experienced
meteorologists to use but is not end-user material. The models are just
not good enough for that and this present situation is a perfect
example of that. It does the reputation of the Met Office no good at
all.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr

Norman Lynagh wrote:

Freddie wrote:

On Monday, 25 February 2019 07:27:54 UTC, Norman Lynagh wrote:
The met Office forecast for the Peak District issued at 0410 this
morning is a bit odd. For 0600 the weather was forecast to be
sunny despite the fact that sunrise wasn't until 0705. The
forecast temperature for 300m a.s.l. was 11°. In Tideswell, at
300m, the actual temperature at 0600 was -0.4°.

The forecast temperature at 300m for 0900 is also 11°. This also
seems unlikely as the current temp(at 0725) is -0.9°.

I can't explain the "sunny before sunrise" bit, but the temperature
forecast is probably one for the "free air" (or maybe hilltop)
temperature taken from the model forecast, as there is a very low
inversion this morning. I'm guessing you are in a valley of sorts?
At Leek, not so far from you, the temperature was 8.3 at 0700z, with
a dew point of -3.

It's happened again this morning. The Peak District forecast issued at
0343 this morning predicted a temperature of 13° at 300m at 0600
today. Actual temperatures at 0600 we

Tideswell (303m): +0.4°
Buxton (335m): +0.6°
Wardlow (299m): +2.8°
Curbar (251m): +2.6°
Burbage (298m): +2.9°

I raised this issue with the Met Office yesterday. They confirmed that
the temperature predictions in these forecasts are straight out of the
model and that the model isn't handling the low-level inversion very
well. Their response included the following

-------------------------------------------------------------
Of course, the problem with automated data is that it does have the
inevitable downside of performing especially badly in some very
specific weather situations, and causing the errors that you have
rightly mentioned.
-------------------------------------------------------------

My view has always been that raw model output is a tool for
experienced meteorologists to use but is not end-user material. The
models are just not good enough for that and this present situation
is a perfect example of that. It does the reputation of the Met
Office no good at all.

Sorry to keep banging on about this but I think it's pretty appalling.

The Peak District forecast issued at 1718 this evening predicts a
temperature of 9° at 300m at midnight tonight. In Tideswell it's
currently (1930z) 5.6° and falling quite quickly. At 300-350m across
the Peak District it's mostly in the range 5-8° at present. I don't
see any reason why it shouldn't continue to fall and by midnight it
looks certain to be a long way below the predicted 9°. Whether this is
model output or a human product I am not impressed. Anyone with half a
brain in their head could have deduced that the temp would fall away
quickly tonight with clear skies, no wind and a low dew point. If this
is the best that the model can do then it would be best to stop issuing
the product.

If the temp recovers and ends up at 9° at midnight then I'll have to
eat a large slice of humble pie!

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.
https://peakdistrictweather.org
twitter: @TideswellWeathr

Just as well that it isn't winter or it could be quite dangerous for walkers etc.

Hold on..........it is winter.

How could I have forgotten.

Julian Mayes
Molesey
Surrey