A difference between reference time and update time

[idefix37]

@itblocksg
This is not weird and @Korina explained the difference.
NEMS is a model provided by the Meteoblue company.
But this model is different from the model called here METEOBLUE (more exactly Meteoblue AI) in the point forecast:

Additional information:
https://community.windy.com/topic/10316/metoblue-wildly-inaccurate-in-the-sw-usa/8?_=1637514782709

[Korina]

@itblocksg Hello, it would be nice if you could explain why it is weird.

[Zancle10]

Salve, se i tempi di riferimento ufficiali per il modello ECMWF sono 0.00 e 12.00, i due aggiornamenti in più con premium su cosa si basano? Grazie

[Korina]

@zancle10 Hello, this is an old article. You can find the update times at Model updates times.

[ColtonAxel]

I think Reference time is the time when a model starts a new forecast block. The process consists of the following: Initialisation - data are entered into the model, this creates Initial conditions (initialisation time) and then model starts calculating conditions.

[youtubevanced55]

@ColtonAxel thank you so much..

[imran512]

@Korina said in A difference between reference time and update time:

A difference between reference time and update time
Frequently Asked Questions ARTICLE 13 26 12.9k

Reply

Korina
21 Feb 2020, 18:28

Each model has a different update time and it could be confusing what connection does it have with the update time.

Here is the explanation:

Reference time - is the time when a model starts a new forecast block.
It consists of:

Initialisation - data are entered into the model, this creates Initial conditions (initialisation time) and then model starts calculating conditions.
Assimilation - normalisation on data and assembling data for computation.
Computation - calculating the future atmospheric rates of change in time increments.
Data extraction - extracting data into regular forecast intervals.
Data storage - data are stored and written in accessible format.
Data postprocessing - special postprocessing routines

For example model ECMWF has an update interval 12 hours (or 6 hours interval for Premium users), that means the first reference time will be 00:00:00Z (Zulu time) and second one 12:00:00Z.

Update time is time between the reference time and the actual update.
The whole process of data computation takes approximately from 8 to 9 hours.
So for ECMWF model the update times are 07:15:00Z and 19:15:00Z.
See the exact update times here - When and how often are the weather data updated?.

Where to find info about reference and update time:

Thanks for the clarification! The distinction between reference time and update time makes a lot more sense now. It’s interesting to see how much processing goes into generating accurate forecasts.