How wet is too wet to survey
Electricity in the air is normally connected to our storms that fire up in the high plains in the summer. We are lucky that we have big sky's and can keep a look out for them. It's rare that we get rain without thunder. Rain fine, thunder, start looking to get out.
I've gotten a light shock before when picking up the base radio antenna, you know it was passed time when that happens.
I work in South Alabama, gets more rain than Seattle, so working in the rain is just SOP. I use a pop up tent, over the instrument, with the legs nailed down. The Mesa has it's own umbrella, notched to fit through the prism rod, found out the hard way no, in spite of the marketing, they are not waterproof. Ponchos and rubber boots, and rock on.
The no go in rain is the GPS unit, while I use an RPN connection to the CORS network, is too expensive to risk getting wet.
In 1959 when I worked for a firm in Casper, Wyoming after moving there, we were working out in the Gas Hills surveying an open pit uranium mine. One day it clouded up and the sky got dark, but no rain, thunder or lightning. We were running grid lines tying into the walls and berms of an adjacent pit that would be cut out by the mine operations of the pit we were surveying. The transit was set up near the edge of the slope and I was giving the rodman line to set nails at the toe of slope and the edge of the berm at the next level. below. When giving him hand signals for his line, my fingernails would buzz, with a kind of zip-zip sound. I called the party chief over and had him listen to the sound, so he said we'd better get out of there. We tossed a rope down to the rodman and pulled him back up the slope, put everything in the pickup and headed for the trailer we stayed in. The party chief said he'd never heard anything like the zip-zip coming off the end of my fingers.