The MRF MOS computer model, which many 7 day forecasts are based on, is actually pretty good at detecting trends. For instance, the model is forecasting 76 for a high on Saturday and 72 for a high on Sunday with a slightly below chance of rain. Will it actually be those exact temperatures this weekend? Probably not. But with temperatures now in the low to mid 60's, the trend to warmer weather for the weekend is probable.
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Cedar Point Virtual Midway
Coming May 22
http://www.schmidty.com