Wednesday, January 23, 2008

When Does The Low Temperature Usually Occur?

Hello -- it is Chris -- back from sunny and very warm south Florida. A cold front did go through on Sunday and man was it windy down there. I have never seen such constant wind. Sustained 20-30 for 2 days.

I can only imagine what a full blown tropical storm or hurricane must be like. Even with just 20-30 mph winds there was some costal flooding and beach erosion, as well as downed trees and debris.

The pool cushions on the chairs around the pool at the resort were all over, one was on the bottom of the pool!

While I was away, a few people left comments talking about the coldest part of the day -- and how they have observed it is often just after sunrise.

Assuming it is just a normal day with normal weather, no cold fronts, extremely windy situations, etc. then the maximum cooling typically takes place at or after sunrise.

Even though the sun may have risen over the horizon, it takes a while for the sun's rays to overcome the radiational cooling that took place all night -- so despite the sunrise, the temperature continues to fall.

Once the sun's rays are strong enough, and overcomes the escape of heat from the Earth back out into space, the temperature reverses and begins to rise.


  1. I knew it would be a simple explanation. It happened again this morning. -5.0F at 6:30am, then -6.3 at 7:30am.


  2. "The pool cushions on the chairs around the pool at the resort were all over"

    WOW - that must have been a nightmare LOL

    -25 Wind Chill here in Wisconsin!

  3. I just stumbled across one of the coolest things from the NWS of Marquette, MI website's Top News Of The Day. "Winter Storm of 1938". The weather map they reference forced me to search for a clearer version. I did so, and it led me to this! I recommend installing the plug-in. Enjoy, I am!

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  5. Something to be said for the new math, evidently the old math didn't add up correctly. lol

    32 Amt of Snow from the storm
    18 Amt on ground before the storm
    49 Amt on ground after storm

    11.5 Amt of Snow from the storm
    37 Amt on ground before the storm
    41 Amt on ground after storm

    17.7 Amt of Snow from the storm
    31 Amt on ground before the storm
    39 Amt on ground after storm

  6. I think this is related...remind me what the Farenhite scale is based on. I seem to remember Celsius scale was based on the freezing and boiling point of water (0º/100º) at sea-level,etc. but what about 0ºF? My Chemistry & Thermodynamics text books are long buried too deep to make this research worth my while. But I'm curious...