All up trains from platfom 4?

Hot weather working, northbound amershams via platform 1 at Harrow. Southbound from amersham going fast down the local from moor park. This gives the Chiltern diesels a red carpet ride down the fast.

Simply put, the "Hot Weather Plan" is introduced when rail temperatures exceed a pre-determined level. This is mainly connected to the following...

Certain sets of points in the Harrow area - in particular Harrow North Junction - are "unwilling" to operate at their best in hot weather, and prefer to lay, where they are, in the same position, basking in the summer sun.

So, to combat this potential problem, we divert all services to prevent the need to use any of these sets of points. So apart from Chiltern services, all southbound fast services are run via the local lines from Watford South Junction to Harrow. Most (but not all) northbound Amersham services are run through Harrow platform 1 but some will run via platform 3 and then via the northbound local lines.

There is also another set of "lazy / sun-seeking" points south of Harrow station which has meant that trains cannot be crossed over south of the station. So a train from the northbound fast line has to be routed to platform 3 at Harrow (Watford semis in the peak) and a train from the northbound local has to be routed to platform 4. Trains could then, if required, be crossed over north of the station.

We don't cancel any trains, and the delay to fast services is generally 1-3 minutes which is recovered by Finchley Road.

So in answer to the original question "Is it likely to be the same tomorrow" then, if it's quite hot and sunny, then it's likely - but we will run just as many trains, just most of them on the southbound local. If it snows, then trains might be where they should be (perhaps that's not the best example.)

Ah I'll put my thermometer to the rails in the evening now to check whether my journey will involve a cross platform or a via the subway interchange at Moor Park. I wouldn't have to aim to be by the stairs there if I was going cross platform.

(Don't worry, I won't actually do this, I don't have a thermometer )

Aside from a short section on the Picc, do other lines have the luxury of four tracks?

The answer to your question is therefore the same as it is to mine!

(that's a no if you are not in the know! ;D ;D)

All other lines can do is introduce emergency temporary speed restrictions and hope the equipment doesn't melt or buckle. It all boils down to maintenance and correct installation of the correct stuff in the first place.........much the same as with the issues that winter brings with it.