The following might be of interest to you, I posted the following on the forum a while back answering another member’s question:.
“The “Horizontal Falls” are well worth the visit, you can access them by both air and boat. My wife and I have done both and there are for´s and against for each type trip: the big advantage by air is that you get a complete overview from above but the disadvantage is that you only spend approx 10 to 20 mins at the falls themselves, the flight followed the coast and we had some great views of the red cliffs, white sand and unbelievable turquoise blue sea along the way.
With the boat trip you get to spend more time around the falls and are more leisurely, there are a number of different 2 to 3 day trips in the tourist season. There is now I believe a combined flight/boat day trip out of Broome or Derby and you get the “best of both worlds”.
You must remember that that the trips are always subject to tidal conditions so you might have to wait around a couple of days to get the correct tides.
I would advise that you go and visit the “Broome Visitors Centre” they are really helpful and will advise you which are the best trips to book (there is/was a German speaking lady staff member last time I was there November 2010).
I have a completely different opinion to the previous poster (as the saying goes “one mans treasure is another mans poison”!) the Gibb river road in my opinion is one of the “must do trips” and you should have no problem going it alone with your wife, as long as you take the right precautions, regarding the choice of vehicle you must have a 4wd to explore all the many fantastic places along the way, (perhaps another member can advise you on 4wd hire/model as we have our own). If you take into account time spent in Broome, Cape Leveque, Bungle Bungles, Kununurra, Keep River NP (just over the border in NT), exploring the various sections of the Gibb River Road, Tunnel Creek just to mention a few, 5 weeks is just about right. You should try and plan your trip with the following in mind:
Mid December to April should be avoided as it’s the “wet season” and many of the tracks will be closed completely and I would recommend not travelling over this period.
May to June is a “perhaps time” as you find that after a heavy “wet season” the road/tracks could still be impassable and the “ Pentecost River” might be still flowing too fast and too high to cross, check conditions either in Broome, Derby if travelling east or in Kununurra if going west, also there are at both ends of the Gibb River Road warning signs of road conditions and closures.
July to September I would say is the best time to travel; weather is generally good and has the added advantage if you should need help there are plenty of tourists around to help you out.
October to mid December is the start of the “wet season build-up” and day time temperatures can be in excess of 45°C and overnight does not often get below 30°C, if you don’t mind the heat it can be a very rewarding time (its our favourite time of year) as you have almost everything to yourselves as the tourist season has finished but remember you will be virtually on you own and should you need help it could be days before someone comes along! Also be prepared for sudden storms that could leave you stranded.
Facit: If you don’t mind your own company, like to get away from it all, enjoy the Australian “outback” and the unbelievably beautiful and amazing scenery that comes with it, then the “Kimberley” is for you ………as they say “If you never never go you will never never know”
Hope the above might help you in you planing and I am sure if you decide to visit the Kimberley’s you will not be disappointed but I would not say anything else we just love the place!!!”
Personally for me and my wife its one of the best times of the year to do the trip most of the tours and tourists have gone (Gibb river road and the Kimberley´s in particular), weather is never predictable, especially in the “build up” usually you will find that the mornings are mostly sunny and the clouds build up in the afternoon and short heavy storms can occur at any time (we had a few years ago in the Bungle Bungles in October a spectacular storm with heavy rain, thunder and lightening with the track becoming unpassable for a day) as I have already written it can get extremely hot and humid and the temperatures overnight can be uncomfortable.
Taking everything into account our opinion it’s a great time to do your trip Darwin-Perth! Enjoy.
Kind regards, Aussie1