After hearing some bad luck stories, i thought it might be a good topic to write about my experiences with weather in the gramps / araps. It seems that lots of international climbers are coming to the gramps and leaving bitter about the bad weather. Anyhow these are my thoughts of 14 years of climbing there.
January & February - Often too hot for maximum sending. You will be sweating and slipping on the frictiony grips. Climbing is possible in shade. Best chances of good weather are first two weeks Jan. Early starts and late evening are good. Avoid routes requiring friction (taipan & spurt wall). Camping is tough with lots of flies. Expect average temps of 30 degrees plus.
March - First two weeks are often much like Jan Feb ( Hot ). 2nd two weeks the temperature generally plummets to low 20's. My favourite time to start climbing.
April - The best time to be there. Stable weather in the low 20's. One or two rainy days here and there.
May - The temperature can drop (Low teens) , but so can the rain. Expect whiteout / misty conditions at times. The worst conditions in the gramps are often when the mist is hanging in the air. This generally lasts a few days. Unfortunately this is rarely shown on the forecast.
June - I have only ever had dry winters in the middle of the drought. We are currently NOT in a drought. Expect rain, grey skies and the dreaded hanging mist. Avoid water streaks, or seepy crags. Its often hard to predict the good days, as the forecasts are often incorrect. Sometimes the rain lasts weeks. Its technically not cold, but the constant grey skies can be very depressing.
July - Much the same as June, with perhaps one more sunnier day.
August - I generally go to Nowra.... However, this is when the weather suddenly changed this year. Was a great month for sunny crags.
September - Yes the sun starts to come out and the crags are dry. Some showery days but generally not bad. Best conditions are generally last two weeks.
October - Apparently Chris Sharma is counting down how many October's he has to climb at his peak. This is because October is generally a stellar month everywhere. The gramps is no different. Probably the second best month to climb here.
November - A good month to climb as its dry and warm. Think high 20's to low 30's at worst.
December - Can be a mixed bag. Lately we have had very mild Decembers with temperatures struggling to get above 30. Often there will be one week with consecutive days in the mid 30's.
I hope some travellers find this useful. I hope others can add useful comments.