Part of our Getting On The Air guide.
Winter Field Day gets treated as a footnote to the June ARRL Field Day, and I think that undersells it. It is run by the Winter Field Day Association rather than ARRL, it happens on the last full weekend of January, and cold weather changes enough about the operation that it deserves its own guide rather than a paragraph tacked onto the summer event.
How It Differs From June Field Day
The format is broadly similar: a 24-hour operating period, emergency-power-focused scoring incentives, and a mix of HF, VHF, and digital contacts. But Winter Field Day’s class categories emphasize indoor versus outdoor operation more explicitly, since setting up an outdoor tent station in January in much of the country is a genuinely different proposition than in June. Many groups that run elaborate field setups in summer shift to operating from a heated building, a garage, or even someone’s home shack for Winter Field Day, while still running on emergency power to keep the spirit of the exercise intact.
Arizona flips this whole equation. Summer Field Day in June routinely hits 105 degrees or hotter here, which makes an outdoor tent setup miserable by mid-afternoon and genuinely risky if you are not careful. Winter Field Day in the 70s is, for most of us, the more comfortable event of the two. A lot of Arizona hams run ARRL Field Day from home or up in the higher elevations to dodge the heat, then set up outside for Winter Field Day when the weather actually cooperates.
Cold Weather Power Considerations
Battery performance drops meaningfully in cold weather, and this matters a lot more for a January event than a June one. LiFePO4 batteries in particular lose usable capacity as temperatures drop, and charging LiFePO4 cells below freezing can actually damage them if your charge controller does not have low-temperature protection built in. If you are running battery power outdoors, either keep your battery bank insulated and above freezing, or plan around reduced runtime and budget extra capacity accordingly. Generators handle cold better but need fresh fuel and reliable cold-start capability, which is worth testing before the event weekend rather than discovering a problem in the field.
Station Setup for Cold Weather
- Keep your operating position heated if you are outdoors at all, since operator comfort and dexterity matter more than people expect for a 24-hour event.
- Radios and laptops generally handle cold fine when running, but condensation when bringing cold gear into a warm space (or vice versa) can be a real problem. Let gear acclimate before powering it on if there has been a significant temperature swing.
- Coax and cables get stiffer and more prone to cracking in cold weather. Handle them gently and check connectors more carefully than you would in summer.
- Antenna setup in snow or frozen ground changes your options for radials and stakes. Plan your antenna choice with this in mind rather than assuming your summer setup translates directly.
Scoring and Categories
Winter Field Day uses class categories similar in spirit to June Field Day, distinguishing between indoor, outdoor, and home stations, along with power source bonuses for running on emergency power like batteries, solar, or generators rather than commercial power. Check the current year’s Winter Field Day Association rules before the event, since specific point values and category definitions can shift slightly year to year.
Why It Is Worth Doing
Winter Field Day is honestly a better emergency preparedness exercise than June Field Day in some ways, precisely because cold weather is when a real grid-down event is hardest to manage. If your summer Field Day setup has never been tested in genuinely cold conditions, Winter Field Day is the low-stakes way to find the gaps in your cold-weather gear and habits before you actually need them.