What is the weather like?
- During Pennsic, days can be very hot and humid – temperatures of over 100°F (37°C) are not uncommon. Meanwhile, temperatures can drop drastically at night, even into the 40's (4°C). There is usually at least one big rainstorm during the two-week period, sometimes with high winds.
Because you'll be outdoors many more hours of the day than usual, be sure to wear sunscreen, even on overcast days. A hat or veil on your head will not only keep the sun off your skin and out of your eyes, but will also help to keep the sun from cooking your brain. While sunglasses are not period, many Pennsic-goers do choose to wear them. Be sure you drink enough water and keep your electrolytes balanced, and remember that alcohol and caffeinated beverages will dehydrate you. Heat can also diminish your appetite, so be sure you eat enough for your activity level. Don't count on having trees in your camp – if you want to have shade, bring a shade fly to create your own.
For those times that it gets cold or wet, a good cloak is a treasure. But if you don't have one, don't hesitate to wrap a blanket around yourself, wear a raincoat, or even use an umbrella. Staying warm and healthy is far more important than looking historically accurate. As a precaution against serious storms, many people keep a dry set of modern clothing in a waterproof container or in their car.
Bring enough bedding to keep you warm at night. A dry cloak makes a great extra top blanket when the temperature drops. Also, a snug cap will keep your head, and you, warm. Remember that air mattresses act as convection cells, and will suck the heat out of your body and pump it into the ground. Try to get it off the ground, or put something (carpet, blanket, etc.) between it and the ground to insulate it. Also, if you make your bed before the sun sets, it will keep the evening dew from settling on your bed and leaving you with clammy sheets.
There are more details about Pennsic weather patterns in Bart the Bewildered's Pennsic guide.