What weather condition can lower your mpg at least 10%?

[Waynetc]

Today - good ice storm while the car was parked at work. I have no idea how much added weight this was, but the coating was quite thick and the mpg dropped over 10% on the trip home. Hey Mike how about a body panel heating device?

[Rick Reece]

A very heavy rain (Severe thunderstorm/huricane) can drive the mpg way down in highway driving. Depending on the standing water I have had times when I couldn't maintain speed in 4th having already downshifted from 5th. Have fun, Rick

[tubesguy]

What weather condition can lower your MPG at least 10%? Wisconsin weather.

[Fred]

Just plain cold weather will do it!

Went to Willow Grove the other day, from the Poconos that was a two hundred some mile round trip down the PA Turnpike and never got more than 67.5 MPG!

Several times last year in the Summer, made the same run and got used to 84 or so MPG for the exact same trip.

Just plain cold weather will do it.

Fred / Proud Owner of "The Silver Bullet"

[griller]

Rain, Rain, and more rain.

a couple weeks ago I drove from San Francisco to Los Angeles, the first 300 miles in rain, often so heavy it was difficult to see 100 yards. 1/4 inch of water on the road in places.
I struggled to keep my mileage up in the low, low sixties. Finally caught a break in the early evening for the last 125 miles when I got clear weather.

all in all it turned a 450 mile trip where I expected to get low 70's into a struggle to even keep my average.

oh yeah and I had headwinds going up to SF. Arrrrrrrgh.

edit: OH YEAH another thing that lowers your mileage 10% is when the *****fool parking varlets leave your engine running to WARM THE CAR UP!!!! this happened to me at the Hyatt on Embarcadero in SF. Shot the previous days hard earned mileage, I could have strangled them.

[Fred]

Just plain cold weather will do it!

Went to Willow Grove the other day, from the Poconos that was a two hundred some mile round trip down the PA Turnpike and never got more than 67.5 MPG!

Several times last year in the Summer, made the same run and got used to 84 or so MPG for the exact same trip.

Just plain cold weather will do it.

Fred / Proud Owner of "The Silver Bullet"

Made that same run again just the other day and the temperature was in the mid-forties. At the same destination I ended up with just under 75 MPG! As one indiviual noted, rain (high humidity) may lower your MPG abilities with these little cars but cold weather will definately do it.

Hope this helps some.

Fred / Proud Owner of "The Silver Bullet"