In our years of working with screen inks, paints and clears...... it has always been a combination of conditions. When the frost is on the pumpkin, you must mix your liquids for a particular kind of inkie dunkin', but when the weather's hot and sticky.... that's the time for regular inkie dunkin'.
You have to be aware of your surroundings and realize that there is no exact science for most any of this stuff, unless you have a year-round temperature controlled facility. You're always going to be mixing a little heavy or light, thinning or retarding your inks and paints.
Usually, the spiderwebbing comes from the ink being too thick and drying before the air can do it naturally. It's probably drying in the screen for you, also. Thin it down by 10% and if that doesn't do it..... box it out and go in 5% increments until you have your desired consistency. Mark all of your finding and either write it all down or store it away in your
computer under screen printing tips. These things will eventually be ingrained into your brain and you won't have to second guess yourself anymore.
What you're building up is experience and when something isn't used very often, we many times forget and get caught wasting time and money. Lucky for many of us here, we have :signs101: to come to for our help.