Friday, January 23, 2009

Correction On Fog & Precipitation

I talked with Nolan today and I stand corrected on the freezing fog comment in my last blog.

Freezing fog -- or any moisture deposition from fog -- DOES COUNT as precipitation since it is deposition from cloud water.

It just happens to be a cloud at or near ground level instead of thousands of feet in the air.

Frost and Dew, however, formed on clear nights, does NOT count as precipitation.

See -- all your comments and blog interaction has taught me something new today!!


  1. Excellent! After reading the past entries comments, it makes sense. Fog is a cloud. Thanks for the clarification guys! Now if I could only experience some freezing fog here in Oshkosh, WI. I'll take any kind of Winter precip at this point.

  2. And as the sun rises... speak of the devil. Freezing Fog has accumulated on the trees, decks, tables. Only a Trace amount, but none the less. I will be reporting a Trace today. :)

  3. Thanks for the clarification!

    Can I again put in a plug for an update to the training slides, and also for a "quick reference guide" with useful information in questionable situations such as this?

  4. Oh good - then we are reporting it correctly! Thanks for the clarification.

  5. Thanks for the clarification Chris. I was not counting that as precip, but Nolan's explanation makes sense.

    I'm with OSNW3...I'm going through winter weather withdrawal, too. I'm tempted to measure the dead grass in my yard just to measure something!

  6. Glad to have been involved in this discussion. I would not wish freezing fog on anyone if it is anything like what we have had in this region - we still have power outages in Lincoln County, WA.

    If anyone is interested I have some images of what "frozen fog" did on my property.

  7. I see ice/freezing fog on my way to work every day. I am fortunate that the fog is not in my area, but the Grand Coulee area has been hit hard. The town of Wilbur has had power outages for about 10 days now due to the fog. Electric Power crews cannot keep up with all the power lines that are falling due to the weight of the precipitation on the wires. One teacher at the school counted 74 power trucks on her way to Spokane, an 80 mile drive. Osh Kosh, you do not want freezing fog, believe me.

  8. WxWatcher, I am in need of some snowfall, indeed!

    Bob, I'd love to see some of your photos.

    BettyAnne, it is obvious I do not want Freezing Fog to the extreme you all are witnessing/enduring. We did, however, have some Freezing Fog overnight. I took a few photos, and you will notice how light it was. (photos HERE)

  9. I got so inspired by some of you folks I created a blog – WX Ranger NW. I have one image of frozen fog on the blog now and will post a few more later.

    It sounds like BettyAnne may drive by my place as she mentions several places nearby.


  10. Please correct your comments about frost in the item after our observation to show that frost caused by fog is reportable.