# UM\_READDUMP error on second LAM forecast

**URL:** <https://cms-helpdesk.ncas.ac.uk/t/um-readdump-error-on-second-lam-forecast/916>\
**Category:** Unified Model\
**Tags:** ARCHER2\
**Created:** [15 February 2023 10:22 UTC](https://cms-helpdesk.ncas.ac.uk/t/um-readdump-error-on-second-lam-forecast/916 "2023-02-15T10:22:12Z")\
**Posts on this page:** 1\
**Showing post:** 8

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**Author:** ![shakka](https://dub1.discourse-cdn.com/flex013/user_avatar/cms-helpdesk.ncas.ac.uk/shakka/32/111_2.png) [@shakka](https://cms-helpdesk.ncas.ac.uk/u/shakka)\
**Post date:** [16 February 2023 16:16 UTC](https://cms-helpdesk.ncas.ac.uk/t/um-readdump-error-on-second-lam-forecast/916/8 "2023-02-16T16:16:24Z")

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Sorry to drag you back in @grenville , but the plot thickens…

I’ve taken all the STASH out and sequentially added them back in (painstakingly), and it seems that I’m getting errors when any outputs related to the large-scale cloud scheme are used.

So far the following have all been causing crashes:

TOTAL PRECIPITATION RATE 05216  
LARGE SCALE SNOWFALL RATE 04204  
LARGE SCALE RAINFALL RATE 04203  
TOTAL COLUMN QCF RHO GRID 30405  
TOTAL COLUMN QCL RHO GRID 30406  
TOTAL COLUMN Q (WATER VAPOUR PATH) 30461

The specific error is

> Error from routine: EXPPXI  
> [0] ? Error message: Invalid item number 0

Immediately before this in the pe outfile it has this message:

> LOOKUP TABLE  
> [0] 216000 64-bit words long  
> [0] WARNING: User defined field found - STASH code : 0  
> [0] Setting internal model number to atmosphere.  
> [0] WARNING: User defined field found - STASH code : 0  
> [0] Setting internal model number to atmosphere.  
> [0] READFLDS: reading 3375 fields with all-to-all algorithm  
> [0] readflds[0] : reading fields 1 to 211 on this PE.

which sounds like the UM is potentially mis-reading these stash entries?

Have you got any ideas where this is coming from? I can’t see anything untoward in e.g. app/um/rose-app.conf

Classically, the one thing I want to focus on for this simulation is the impact of cloud composition on precipitation events, so these are quite crucial diagnostics!

Cheers  
Ella

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