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Website for frost warning look up

imaguitargod

imaguitargod

Ok, I've searched and searched but can't find it. I need a site that I can look at that will show the dew point for the following week. I checked weather.com and all I could find there was the prediction for the next two days (via their hour-by-hour look up).
 
MiLK_MaN said:
Whats the trigger point you look for when deciding whether to take action or not?
Click to expand...
When the dew point reaches freezing (34 degrees fairenheit). That's when you want to cover the plants.
 
Iggy,

You sure about the Dew Point being a measure of a killing frost? This past week, the weather guys were talking about Dew Points in the 30s but our temps were in the mid 50s.

As for finding out the forecast for a killing frost - I watch the 11:00 news!

Mike
 
What you need to worry about is when the real temperature get a few degrees below 32F. Only a hard frost should kill your plants.

Heres what I do, every day I check out my 5 day forecast at wunderground.com

just put in your zipcode, assuming you live in the US. It refreshes perioticly, just monitor the lows... and when they get within a few degrees of freezing, keep an eye out that day or night, if you have any plants you need to rescue.
 
From "AskAScientist" --> http://www.newton.dep.anl.gov/askasci/wea00/wea00039.htm

Question - I would like to know how to determine whether or not frost
will appear on the ground. I assume you need dew to get frost, and dew is
dependent on the dew point, which is easy to find information about (e.g.
http://paroscientific.com/dewpoint.htm). Basically then, my question is
how can you estimate ground temperature given air temperature or possibly
air temperature history? Does heat transfer between the ground and air
play a significant role?
------------------------------------------------
Let me answer just a part of your question. Your assumption is incorrect.
Frost is not made by freezing dew. It is formed by sublimation - water vapor
moving directly to a solid... ice. Frost is formed when the dew point is near
or below freezing and the temperature of the air falls to within a few degrees
of the DP.

Your thought about ground temperature is interesting. Generally the air is
warmed or cooled by the surface. The air is largely transparent to radiant
energy so heat released by the surface at night is radiated off into space.
But as the surface cools, the heat from the lowest layer of air is
conducted to
the ground. Cooling the air from below tends to make the air more stable and
keep the cooler air low.

Hope that helps.

Larry Krengel
Click to expand...

Also, keep in mind the Heat Island effect, for example I live near downtown, and the temps here are alwayse at least 2 F higher than the temps outside the city.
 
Maybe I should add one thing... The only thing due point has to do with "frost" is, in effect it's when the water in the atmospehere turns into a vapor or tinly dropplets of water that you can see as fog and this stuff (when the temps are low enough) is the actuall frost that coats things outside.

What kills a plant is not necessarily the frost, it's when the air temperatures reach freezing and the water inside the plant cells turns into ice, breaks open the cell walls and kills them.

Now, it could be freezing and there could be no water in the atmosphere at all, and no frost will develop but that doesnt mean that your plants are safe.

If it's cold enough to make water turn into ice, then your plants are in danger.
 
Hopefully I had to move the plants into the garage for the last time this growing season, got to about 5.6C overnight here in my area of Melbourne.
 
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