Luggage and bags:
Travel light with t-shirts as Surabaya is hot all year round.
Clothing/Shoes/Weather Gear: Your jacket and two layers of t-shirt should survive the early morning cold breeze at Gunung Penanjakan. Once the sun is up a t-shirt will do.
Photo Equipment: Bring along plenty of films or memory cards when you visit Mt Bromo.
Clothing/Shoes/Weather Gear: I would say where light clothes as its hot in Surabaya but I would say take warm clothes with if you plan on going to Mt Bromo as its really cool up there especially if you plan to go and see the sunrise.
Clothing/Shoes/Weather Gear: Surabaya is hot. So just bring thin clothes. I usually wear jacket (why? not because I feel cold, but for protecting me from sunlight, as it will make my skin burnt..... J
since Surabaya is hot, just take simple thin clothes with you. There's no need to bring a jacket. But it may be useful if you wish to visit, for instance, Mount Bromo, Tretes, or Batu (for visitors from europe or america, I'll tell you that it is not so cold for you. The temperature never falls below 10oC, except at peak of Bromo.
Miscellaneous: if you go to surabaya in december until march, i recommend you to bring your umbrella, because of rainy season (it usually rains in the evening).
sleveless or casual tshirt is fine... plus, a rain coat, not d thick heavy one coz it's still warm even though it's raining... no jacket necessary unless u wanna perspire like crazy (plus, it makes u look stupid)
Toiletries and Medical Supplies: bring some own medical supply from ur own country.... d dose of indonesian drugs r really high (that's why Dutch medicine hadn't done me any good)
Luggage and bags:
Bring medium-sized luggage, since most cars in the city is relatively medium in size (unless you intend to take bus/private airport transfer service/hotel's MPV to travel to and from the airport). If you get around by taxi, traveling light would save you headache and the hassles.
Clothing/Shoes/Weather Gear: Short sleeves, shorts, sandals, running shoes or sneakers are sufficient. In months when the rain is quite heavy (generally between the end of the year -around September to April/May), raincoat and umbrella would be needed. You can buy or carry foldable umbrella inside your bag for easy use whenever you go outside. Foldable umbrellas generally cost $2 or IDR 20.000 in big stores like Carrefour and Giant.
Toiletries and Medical Supplies: Bring a travel pack of tissues and/or wet tissues. Some public toilets in malls often run out of tissues. Since the weather tend to be hot and humid, mosquito repellent is important. You can bring along handy aromatic gels and antibacterial solution, especially if you intend to try the public transportation. Plaster for unexpected accidents, ointment oil for sprains and other common first-aid kit items. Bring medication for stomachache/upset stomach, as your stomach might not be able to handle the spicy foods, petis (shrimp paste), and other local spices generally used to make flavorful dishes.
Photo Equipment: bring waterproof camera case to dodge rain water and durable, rugged camera case/bag with handle to avoid thief/street's snatch-and-go.
Camping/Beach/Outdoor Gear: tent, waterproof rug/carpet, sleeping bag, anti-mosquito net
Miscellaneous: sunscreen lotion, brimmed hat/baseball cap