Table 5: Diabatic Processes


See here for an explanation of the significance of the quantities tabulated here.

IOP 900mb 500mb 300mb
Max PV within low (PVU)* Distance from low centre to maximum (km) Downstream Upstream Downstream Upstream
Min PV value within 500km downstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km upstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km downstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km upstream of low centre (PVU)* Distance from low centre to minimum (km)
1 1.4 75 0.1 500 0.1 450 -0.2 400 -1.0 400
2 1.0 - 0.2 450 - - -0.3 500 - -
4 0.5 0 0.3200 0.4 500 0.0 400 - -
5 0.8 0 - - - - - - - -
6 1.0 - 0.2 450 0.2 450 -0.3 300 0 300
7 No maximum No centre 0.2 350 - - 0.3 500 - -
9 2.7 200 0.2 500 0.2 100 -0.4 500 0.7 450
10 0.8 No centre 0 200 0.1 200 0.3 100 - -
11 0.8 No centre 0.4 500 - - -0.1 500 - -
11a 0.7 50 - - - - 0.8 300 - -
12 1.3 ? 0 500 - - -0.1 500 0 -
15 1.6 500 0.2 500 - - -0.3 500 - -
16 0.9 100 0.2 200 - - -0.2 500 0 400
17 1.7 50 0.2 500 -0.3 500 -0.5 450 -0.3 100
18 1.1 100 0.0 400 >0.3 150 0.5 500 4 150
19 1.2 ? - - - - - - - -
IOP 900mb 500mb 300mb
Max PV within low (PVU)* Distance from low centre to maximum (km) Downstream Upstream Downstream Upstream
Min PV value within 500km downstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km upstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km downstream of low centre (PVU)* Distance from low centre to minimum (km) Min PV value within 500km upstream of low centre (PVU)* Distance from low centre to minimum (km)

* Before end of MSA obs. red if within area of MSA aircraft obs.


Humphrey W Lean | | hwlean@meto.gov.uk